Severe Osteoporosis in a Young Man with Bilateral Cushing’s Syndrome

Abstract

Background

The diagnosis of Cushing’s syndrome is challenging; however, through the clinical picture and the search for secondary causes of osteoporosis, it was possible to reach the diagnosis of the case reported. There was an independent, symptomatic ACTH hypercortisolism manifested by typical phenotypic changes, severe secondary osteoporosis and arterial hypertension in a young patient.

Case presentation

A 20-year-old Brazilian man with low back pain for 8 months. Radiographs showed fragility fractures in the thoracolumbar spine, and bone densitometry showed osteoporosis, especially when evaluating the Z Score (− 5.6 in the lumbar spine). On physical examination, there were wide violaceous streaks on the upper limbs and abdomen, plethora and fat increase in the temporal facial region, hump, ecchymosis on limbs, hypotrophy of arms and thighs, central obesity and kyphoscoliosis. His blood pressure was 150 × 90 mmHg. Cortisol after 1 mg of dexamethasone (24.1 µg/dL) and after Liddle 1 (28 µg/dL) were not suppressed, despite normal cortisoluria. Tomography showed bilateral adrenal nodules with more severe characteristics. Unfortunately, through the catheterization of adrenal veins, it was not possible to differentiate the nodules due to the achievement of cortisol levels that exceeded the upper limit of the dilution method. Among the hypotheses for the differential diagnosis of bilateral adrenal hyperplasia are primary bilateral macronodular adrenal hyperplasia, McCune–Albright syndrome and isolated bilateral primary pigmented nodular hyperplasia or associated with Carney’s complex. In this case, primary pigmented nodular hyperplasia or carcinoma became important etiological hypotheses when comparing the epidemiology in a young man and the clinical-laboratory-imaging findings of the differential diagnoses. After 6 months of drug inhibition of steroidogenesis, blood pressure control and anti-osteoporotic therapy, the levels and deleterious metabolic effects of hypercortisolism, which could also impair adrenalectomy in the short and long term, were reduced. Left adrenalectomy was chosen, given the possibility of malignancy in a young patient and to avoid unnecessary definitive surgical adrenal insufficiency if the adrenalectomy was bilateral. Anatomopathology of the left gland revealed expansion of the zona fasciculate with multiple nonencapsulated nodules.

Conclusion

The early identification of Cushing’s syndrome, with measures based on the assessment of risks and benefits, remains the best way to prevent its progression and reduce the morbidity of the condition. Despite the unavailability of genetic analysis for a precise etiological definition, it is possible to take efficient measures to avoid future damage.

Peer Review reports

Background

Cushing’s syndrome may be exogenous or endogenous and, in this case, can be ACTH-dependent or independent. In the case reported, there was an independent, symptomatic ACTH hypercortisolism manifested by typical phenotypic changes, severe secondary osteoporosis and arterial hypertension in a young patient. Osteoporosis secondary to hypercortisolism occurs due to chronic reduction in bone formation, loss of osteocytes and increased reabsorption caused by intense binding of cortisol to glucocorticoid receptors present in bone cells [1]. In addition, excess cortisol impairs vitamin D metabolism and reduces endogenous parathyroid hormone secretion, intestinal calcium reabsorption, growth hormone release, and lean body mass [2]. Subclinical Cushing disease occurs in up to 11% of individuals diagnosed with early-onset osteoporosis and 0.5–1% of hypertension patients. [3] A cross-sectional study published in 2023 revealed a prevalence of 81.5% bone loss in 19 patients with Cushing’s syndrome [2]. The prevalence of osteopenia ranges from 60 to 80%, and the prevalence of osteoporosis ranges from 30 to 65% in patients with Cushing’s syndrome. Additionally, the incidence of fragility fractures ranges from 30 to 50% in these patients [4] and is considered the main cause of morbidity affecting the quality of life. The diagnosis is challenging, given the presence of confounding factors; however, through the clinical picture and the search for secondary causes of osteoporosis, it was possible to reach a syndromic diagnosis. Early identification of this syndrome, with measures based on the assessment of risks and benefits, remains the best way to prevent progression and reduce morbidity related to this disease [2].

Case presentation

A 20-year-old Brazilian male patient reported low back pain that had evolved for 8 months, with no related trauma. He sought emergency care and performed spinal radiographs on this occasion (03/2019). Due to the several alterations observed in the images, he was referred to the Orthopedics Service of the Hospital of Federal University of Juiz de Fora, which prescribed orthopedic braces, indicated physical therapy and was referred again to the Osteometabolic Diseases outpatient clinic of the Endocrinology and Rheumatology Services of the Hospital of Federal University of Juiz de Fora on 10/2019.

The radiographs showed a marked reduction in the density of bone structures, scoliotic deviation with convexity toward the left and reduction in the height of the lumbar vertebrae, with partial collapses of the vertebral bodies at the level of T12, L1, L2, L3 and L5, with recent collapses in T12 and L1, suggesting bone fragility fractures. The same can be seen in posterior magnetic resonance imaging (Fig. 1).

Fig. 1

figure 1

Radiography and Magnetic Resonance Imaging (MRI) of lumbosacral spine in profile

Bone scintigraphy on 08/2019 did not reveal hyper flow or anomalous hyperemia in the topography of the thoracolumbar spine, and in the later images of the exam, there was a greater relative uptake of the tracer in the lumbar spine (vertebrae T10–T12, L2–L4), of nonspecific aspect, questioning the presence of osteoarticular processes or ankylosing spondylitis.

It was also observed in the bone densitometry requested in October 2019, performed by dual-energy X-ray absorptiometry (DXA), low bone mineral density (BMD) in the lumbar spine, femoral neck and total femur, when comparing the results to evaluating the Z Score (Table 1).

Table 1 Dual-energy X-ray absorptiometry (DXA)

Thus, the diagnosis of osteoporosis was established, and treatment with vitamin D 7000 IU per week was started due to vitamin D3 insufficiency associated with the bisphosphonate alendronate 70 mg, also weekly. The patient had a past pathological history of fully treated syphilis (2018) and perianal condyloma with a surgical resection on 09/2017 and 02/2018. In the family history, it was reported that a maternal uncle died of systemic sclerosis. In the social context, the young person denied drinking alcohol and previous or current smoking.

On physical examination, there were no lentiginous skin areas or blue nevi; however, wide violet streaks were observed on the upper limbs and abdomen, with plethora and increased fat in the temporal facial region and hump (Fig. 2a, b), limb ecchymosis, hypotrophy of the arms and thighs, central obesity and kyphoscoliosis. Systemic blood pressure (sitting) was 150 × 90 mmHg, BMI was 26.09 kg/m2, and waist circumference was 99 cm, with no reported reduction in height, maintained at 1.55 m.

Fig. 2

figure 2

Changes in the physical examination. a Violet streaks on the upper limbs, b Violet streaks on abdomen

An investigation of secondary causes for osteoporosis was initiated, with the following laboratory test results (Table 2).

Table 2 Laboratory tests

Computed tomography of the abdomen with adrenal protocol performed on 08/13/2020 characterized isodense nodular formation in the body of the left adrenal and in the lateral portion of the right adrenal, measuring 1.5 cm and 0.6 cm, respectively. The lesions had attenuation of approximately 30 HU, showing enhancement by intravenous contrast, with an indeterminate washout pattern in the late phase after contrast (< 60%) (Fig. 3).

Fig. 3

figure 3

Computed tomography abdomen with adrenal protocol

After contact with the interventional radiology of the Hospital of Federal University of Juiz de Fora, catheterization of adrenal veins was performed on 10/2020; however, it was not possible to perform adequate lesion characterization due to obtaining serum cortisol levels that extrapolated the dilutional upper limit of the method (Table 3).

Table 3 Adrenal catheterization

The calculation of the selectivity index was 6.63 (Reference Value (RV) > 3), confirming the good positioning of the catheter within the vessels during the procedure. The calculated lateralization index was 1.1296 (VR < 3), denoting bilateral hormone production. However, as aldosterone was not collected from a peripheral vein, it was not possible to obtain the contralateral rate and define whether there was contralateral suppression of aldosterone production [5].

Due to pending diagnoses for a better therapeutic decision and Cushing’s syndrome in clear evolution and causing organic damage, it was decided, after catheterization, to make changes in the patient’s drug prescription. Ketoconazole 400 mg per day was started, the dose of vitamin D was increased to 14,000 IU per week, and ramipril 5 mg per day was prescribed due to secondary hypertension. In addition, given the severity of osteoporosis, it was decided to replace previously prescribed alendronate with zoledronic acid.

Magnetic resonance imaging of the upper abdomen was performed on 06/19/2021, which demonstrated lobulated nodular thickening in the left adrenal gland with areas of decreased signal intensity in the T1 out-phase sequence, denoting the presence of fat, and homogeneous enhancement using contrast, measuring approximately 1.7 × 1.5 × 1.3 cm, suggestive of an adenoma. There was also a small nodular thickening in the lateral arm of the right adrenal, measuring approximately 0.8 × 0.6 cm, which was difficult to characterize due to its small dimensions and nonspecific appearance.

PPNAD or carcinoma became an important etiological hypothesis for the case described when comparing the epidemiology in a young man and the clinical-laboratory-imaging findings of the differential diagnoses. According to a dialog with the patient and family, the group of experts opted for unilateral glandular surgical resection on the left side (11/11/2021), where more significant changes were visualized, as there was a possibility of malignancy in a young patient and to avoid a definitive adrenal insufficiency condition because of bilateral adrenalectomy. This would first allow the analysis of the material and follow-up of the evolution of the condition with the permanence of the contralateral gland.

In the macroscopic analysis of the adrenalectomy specimen, adrenal tissue weighing 20 g and measuring 9.3 × 5.5 × 2.0 cm was described, completely surrounded by adipose tissue. The gland has a multinodular surface and varies between 0.2 and 1.6 cm in thickness, showing a cortex of 0.1 cm in thickness and a medulla of 1.5 cm in thickness (Fig. 4).

Fig. 4

figure 4

Left adrenal

The microscopic analysis described the expansion of the zona fasciculate, with the formation of multiple nonencapsulated nodules composed of polygonal cells with ample and eosinophilic cytoplasm and frequent depletion of intracytoplasmic lipid content. No areas of necrosis or mitotic activity were observed. The histopathological picture is suggestive of cortical pigmented micronodular hyperplasia of the adrenal gland.

For the final etiological definition and an indication of contralateral adrenalectomy, which could be unnecessary and would avoid chronic corticosteroid therapy, or else, it would be necessary to protect the patient from future complications with the maintenance of the disease in the right adrenal gland, it would be essential to search for mutations in the PRKAR1A, PDE11A, PDE8B and PRKACA genes [15]; however, such genetic analysis is not yet widely available, and the impossibility of carrying it out at the local level did not allow a complete conclusion of the case.

Discussion

Through the clinical picture presented and the research of several secondary causes for osteoporosis, it was possible to arrive at the diagnosis of Cushing syndrome [6]. There was symptomatic independent ACTH hypercortisolism, manifested by typical phenotypic changes, severe secondary osteoporosis, and arterial hypertension in a young patient.

The diagnosis of Cushing’s syndrome is always challenging, given the presence of confounding factors such as the following:

  • Physiological states of hypercortisolism—pseudo Cushing (strenuous exercise, pregnancy, uncontrolled diabetes, sleep apnea, chronic pain, alcohol withdrawal, psychiatric disorders, stress, obesity, glucocorticoid resistance syndromes);
  • Cyclic or mild—subclinical Cushing’s pictures;
  • Frequent and, even unknown, short- and long-term use of corticosteroids under different presentations;
  • Increase in the general population incidence of diabetes and obesity;
  • Screening tests with singularities for collection and individualized for different patient profiles.

It is important to note that the basal morning cortisol measurement is not the ideal test to assess hypercortisolism and is better applied to the assessment of adrenal insufficiency. However, the hypercortisolism of the case was unequivocal, and this test was also shown to be altered several times. As no test is 100% accurate, the current guidelines suggest the use of at least two first-line functional tests that focus on different aspects of the pathophysiology of the hypothalamic‒pituitary‒adrenal axis to confirm the hypercortisolism state: 24-hours cortisol, nocturnal salivary cortisol, morning serum cortisol after suppression with 1 mg of dexamethasone or after Liddle 1. Given that night-time salivary cortisol would require hospitalization, the other suggested tests were chosen, which are easier to perform in this context [78].

Subsequently, tests were performed to determine the cause of hypercortisolism, such as serum ACTH levels and adrenal CT. The suppressed ACTH denoted the independence of its action. CT showed bilateral adrenal nodules with more severe features: solid lesion, attenuation > 10 UI on noncontrast images, and contrast washout speed < 60% in 10 minutes. In this case, it is essential to make a broad clinical decision and dialog with the patient to weigh and understand the risks and benefits of surgical treatment [9].

Among the main diagnostic hypotheses for the differential diagnosis of bilateral adrenal hyperplasia are primary bilateral macronodular adrenal hyperplasia, McCune–Albright syndrome (MAS) and bilateral primary pigmented nodular hyperplasia (PPNAD) isolated or associated with Carney’s complex. Another possibility would be bilateral adrenocorticotropic hormone (ACTH)-dependent macronodular hyperplasia secondary to long-term adrenal stimulation in patients with Cushing’s disease (ACTH-secreting pituitary tumor) or ectopic ACTH production, but the present case did not present with ACTH elevation.

Primary macronodular adrenal hyperplasia (nodules > 1 cm) predominates in women aged 50–60 years and may also be detected in early childhood (before 5 years) in the context of McCune–Albright syndrome. Most cases are considered sporadic; however, there are now several reports of familial cases whose presentation suggests autosomal dominant transmission. Several pathogenic molecular causes were identified in the table, indicating that it is a heterogeneous disease [10]. The pathophysiology occurs through the expression of anomalous ectopic hormone receptors or amplified eutopic receptors in the adrenals. It usually manifests in an insidious and subclinical way, with cortisol secretion mediated through receptors for gastric inhibitory peptide (GIP), vasopressin (ADH), catecholamines, interleukin 1 (IL-1), leptin, luteinizing hormone (LH), serotonin or others. Nodular development is not always synchronous or multiple; thus, hypercortisolism only manifests when there is a considerable increase in the number of adrenocortical cells, with severe steroidogenesis observed by cortisoluria greater than 3 times the upper limit of normal. Patients with mild Cushing’s syndrome should undergo screening protocols to identify aberrant receptors, as this may alter the therapeutic strategy. If there is evidence of abnormal receptors, treatment with beta-blockers is suggested for patients with beta-adrenergic receptors or with gonadotropin-releasing hormone (GnRH) agonists (and sex steroid replacement) for patients with LH/hCG receptors. In patients in whom aberrant hormone receptors are not present or for whom no specific pharmacological blockade is available or effective, the definitive treatment is bilateral adrenalectomy, which is known to make the patient dependent on chronic corticosteroid therapy [11]. Studies have shown the effectiveness of unilateral surgery in the medium and long term, opting for the resection of the adrenal gland of greater volume and nodularity by CT, regardless of the values obtained by catheterization of adrenal veins, but with the possibility of persistence or recurrence in the contralateral gland. Another possibility would be total unilateral adrenalectomy associated with subtotal contralateral adrenalectomy [12].

In McCune–Albright syndrome (MAS), there are activating mutations in the G-protein GNAS1 gene, generating autonomic hyperfunction of several tissues, endocrine or not, and there may be, for example, a constant stimulus similar to ACTH on the adrenal gland. In this case, pituitary levels of ACTH are suppressed, and adrenal adenomas with Cushing’s syndrome appear. Hypercortisolism may occur as an isolated manifestation of the syndrome or be associated with the triad composed of polyostotic fibrous dysplasia, café au lait spots with irregular borders and gonadal hyperfunction with peripheral precocious puberty. The natural history of Cushing’s syndrome in McCune-Albright syndrome (MAS) is heterogeneous, with some children evolving with spontaneous resolution of hypercortisolism, while others have a more severe condition, eventually requiring bilateral adrenalectomy [13].

PPNAD predominates in females, in people younger than 30 years, multiple and small (< 6 mm) bilateral pigmented nodules (surrounded by atrophied cortex), which can reach 1.5 cm in adulthood, with family genetic inheritance (66%) or sporadic inheritance (33%), and as part of the Carney complex reported in 40% of cases. In 70% of cases, inactivating mutations are identified in the PKA regulatory 1-alpha subunit (PRKAR1A), a tumor suppressor gene [14]. Osteoporosis is often associated with this condition [15]. One test that can distinguish patients with PPNAD from other primary adrenocortical lesions is cortisoluria after sequential suppression with low- and high-dose dexamethasone. In contrast to most patients with primary adrenocortical disease, who demonstrate no change in urinary cortisol, 70% of PPNAD patients have a paradoxical increase in urinary cortisol excretion [16]. The treatment of choice for PPNAD is bilateral adrenalectomy due to the high recurrence rate for primary adrenal disease [17].

Carney complex is a multiple neoplastic syndrome with autosomal dominant transmission, characterized by freckle-like cutaneous hyperpigmentation (lentiginosis), endocrine tumors [(PPNAD), testicular and/or thyroid tumors and acromegaly] and nonendocrine tumors, including cutaneous, cardiac, mammary, and osteochondral myxomas, among others. In the above case, the transthoracic echocardiogram of the patient on 03/18/2021 showed cavities of normal dimensions, preserved systolic and diastolic functions, no valve changes and no lentiginous skin areas and blue nevi, making the diagnosis of the syndrome less likely. The definitive diagnosis of Carney requires two or more main manifestations. Several related clinical components may suggest the diagnosis but not define it. The diagnosis can also be made if a key criterion is present and a first-degree relative has Carney or an inactivating mutation of the gene encoding PRKAR1A [18].

The adenoma is usually small in size (< 3 cm), similar to the nodules in this case; however, it is usually unilateral, with an insidious and mild evolution, especially in adult women over 35 years of age, producing only 1 steroid class. Carcinomas are usually large (> 6 cm), and only 10% are bilateral. They should be suspected mainly when the tumor presents with hypercortisolism associated with hyperandrogenism. They have a bimodal age distribution, with peaks in childhood and adolescence, as well as at the end of life [3].

Conclusion

Early identification of Cushing’s syndrome, with measures based on the assessment of risks and benefits, remains the best way to prevent progression and reduce morbidity [2]. After 6 months of drug inhibition of steroidogenesis, blood pressure control and anti-osteoporotic therapy, the objective was to minimize the levels and deleterious metabolic effects of hypercortisolism, which could also harm the surgical procedure in the short and long term through infections, dehiscence, nonimmediate bed mobilization and cardiovascular events. Unilateral adrenalectomy was chosen, given the possibility of malignancy in a young patient and to avoid definitive surgical adrenal insufficiency if the adrenalectomy was bilateral. Despite the unavailability of genetic analysis for a precise etiological definition, it is possible to take efficient measures to avoid unnecessary consequences or damage.

Availability of data and materials

All data generated or analysed during this study are included in this published article [and its Additional file 1]. The datasets generated and/or analysed during the current study are available in the link https://ufjfedubr-my.sharepoint.com/:v:/g/personal/barbara_reis_ufjf_edu_br/EVpIR005sPZGlQvMJhIwSaUB0Hig4KOjhkG4D4cMggUwHA?e=Dk8tng.

Abbreviations

ACTH:
Adrenocorticotropic hormone
PPNAD:
Bilateral primary pigmented nodular hyperplasia
DXA:
Dual energy X-ray absorptiometry
GIP:
Gastric inhibitory peptide
GnRH:
Gonadotropin-releasing hormone
IL-1:
Interleukin 1
BMD:
Low bone mineral density
LH:
Luteinizing hormone
MAS:
McCune–Albright syndrome
PRKAR1A:
PKA regulatory 1-alpha subunit
ADH:
Vasopressin

References

  1. Pedro AO, Plapler PG, Szejnfeld VL. Manual brasileiro de osteoporose: orientações práticas para os profissionais de saúde. 1st ed. São Paulo: Editora Clannad; 2021. ISBN 978-65-89832-00-3.

  2. Naguib R, Elkemary EZ, Elsharkawi KM. The severity of bone loss: a comparison between Cushing’s disease and Cushing’s syndrome. J Endocrinol Metab. 2023;13(1):33–8. https://doi.org/10.14740/jem857.

    Article Google Scholar

  3. Vilar L, et al. Endocrinologia Clínica. 6th ed. Rio de Janeiro: Guanabara Koogan; 2016.

    Google Scholar

  4. Wang D, Dang CX, Hao YX, Yu X, Liu PF, Li JS. Relationship between osteoporosis and Cushing syndrome based on bioinformatics. Medicine (Baltimore). 2022;101(43): e31283.

    Article CAS PubMed Google Scholar

  5. Williams TA, Reincke M. Management of Endocrine Disease: diagnosis and management of primary aldosteronism: the Endocrine Society guideline 2016 revisited. Eur J Endocrinol. 2018;179(1):R19–29. https://doi.org/10.1530/EJE-17-0990.

    Article CAS PubMed Google Scholar

  6. Compston J, Cooper A, Cooper C, Gittoes N, Gregson C, Harvey N, National Osteoporosis Guideline Group (NOGG), et al. UK clinical guideline for the prevention and treatment of osteoporosis. Arch Osteoporos. 2017;12(1):43. https://doi.org/10.1007/s11657-017-0324-5.

    Article CAS PubMed PubMed Central Google Scholar

  7. Nieman LK. Diagnosis of Cushing’s syndrome in the modern era. Endocrinol Metab Clin N Am. 2018;47(2):259–73. https://doi.org/10.1016/j.ecl.2018.02.001.

    Article Google Scholar

  8. Herr K, Muglia VF, Koff WJ, Westphalen AC. Imaging of the adrenal gland lesions. Radiol Bras. 2014;47(4):228–39. https://doi.org/10.1590/0100-3984.2013.1762.

    Article PubMed PubMed Central Google Scholar

  9. Hsiao HP, Kirschner LS, Bourdeau I, Keil MF, Boikos SA, Verma S, et al. Clinical and genetic heterogeneity, overlap with other tumor syndromes, and atypical glucocorticoid hormone secretion in adrenocorticotropin-independent macronodular adrenal hyperplasia compared with other adrenocortical tumors. J Clin Endocrinol Metab. 2009;94(8):2930–7. https://doi.org/10.1210/jc.2009-0516.

    Article CAS PubMed PubMed Central Google Scholar

  10. Mircescu H, Jilwan J, N’Diaye N, et al. Are ectopic or abnormal membrane hormone receptors frequently present in adrenal Cushing’s syndrome? J Clin Endocrinol Metab. 2000;85(10):3531–6. https://doi.org/10.1210/jcem.85.10.6865.

    Article CAS PubMed Google Scholar

  11. Miller BS, Auchus RJ. Evaluation and treatment of patients with hypercortisolism: a review. JAMA Surg. 2020;155(12):1152–9. https://doi.org/10.1001/jamasurg.2020.3280.

    Article PubMed Google Scholar

  12. Haddad NG, Eugster EA. Peripheral precocious puberty including congenital adrenal hyperplasia: causes, consequences, management and outcomes. Best Pract Res Clin Endocrinol Metab. 2019;33(3):101273. https://doi.org/10.1016/j.beem.2019.04.007.

    Article PubMed Google Scholar

  13. Bonnet-Serrano F, Bertherat J. Genetics of tumors of the adrenal cortex. Endocr Relat Cancer. 2018;25(3):R131–52. https://doi.org/10.1530/ERC-17-0361.

    Article CAS PubMed Google Scholar

  14. Carney JA, Young WF Jr. Primary pigmented nodular adrenocortical disease and its associated conditions. Endocrinologist. 1992;2:6.

    Article Google Scholar

  15. Stratakis CA, Sarlis N, Kirschner LS, Carney JA, Doppman JL, Nieman LK, et al. Paradoxical response to dexamethasone in the diagnosis of primary pigmented nodular adrenocortical disease. Ann Intern Med. 1999;131(8):585–91. https://doi.org/10.7326/0003-4819-131-8-199910190-00006.

    Article CAS PubMed Google Scholar

  16. Powell AC, Stratakis CA, Patronas NJ, Steinberg SM, Batista D, Alexander HR, et al. Operative management of Cushing syndrome secondary to micronodular adrenal hyperplasia. Surgery. 2008;143(6):750–8. https://doi.org/10.1016/j.surg.2008.03.022.

    Article PubMed Google Scholar

  17. Almeida MQ, Stratakis CA. Carney complex and other conditions associated with micronodular adrenal hyperplasias. Best Pract Res Clin Endocrinol Metab. 2010;24(6):907–14. https://doi.org/10.1016/j.beem.2010.10.006.

    Article CAS PubMed PubMed Central Google Scholar

  18. Hannah-Shmouni F, Stratakis CA. A gene-based classification of primary adrenocortical hyperplasias. Horm Metab Res. 2020;52(3):133–41. https://doi.org/10.1055/a-1107-2972.

    Article CAS PubMed Google Scholar

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Authors and Affiliations

  1. Serviço de Endocrinologia, Hospital Universitário da Universidade Federal de Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil

    Bárbara Oliveira Reis, Christianne Toledo Sousa Leal, Danielle Guedes Andrade Ezequiel, Ana Carmen dos Santos Ribeiro Simões Juliano, Flávia Lopes de Macedo Veloso, Leila Marcia da Silva, Lize Vargas Ferreira, Mariana Ferreira & Gabriel Zeferino De Oliveira Souza

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All the authors contributed to the conception and design of the work and have approved the submitted version. All authors read and approved the final manuscript.

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Correspondence to Bárbara Oliveira Reis.

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Supplementary Information

Additional file 1. Surgical removal of adrenal gland.

The Effect of Biochemical Remission on Bone Metabolism in Cushing’s Syndrome: A 2‐Year Follow‐Up Study

https://doi.org/10.1002/jbmr.4033

 

ABSTRACT

Endogenous Cushing’s syndrome (CS) is a rare cause of secondary osteoporosis. The long‐term consequences for bone metabolism after successful surgical treatment remain largely unknown. We assessed bone mineral density and fracture rates in 89 patients with confirmed Cushing’s syndrome at the time of diagnosis and 2 years after successful tumor resection. We determined five bone turnover markers at the time of diagnosis, 1 and 2 years postoperatively. The bone turnover markers osteocalcin, intact procollagen‐IN‐propeptide (PINP), alkaline bone phosphatase, CTX‐I, and TrAcP 5b were measured in plasma or serum by chemiluminescent immunoassays. For comparison, 71 sex‐, age‐, and body mass index (BMI)‐matched patients in whom Cushing’s syndrome had been excluded were studied. None of the patients received specific osteoanabolic treatment. At time of diagnosis, 69% of the patients had low bone mass (mean T‐score = −1.4 ± 1.1). Two years after successful surgery, the T‐score had improved in 78% of patients (mean T‐score 2 years postoperatively −1.0 ± 0.9). The bone formation markers osteocalcin and intact PINP were significantly decreased at time of diagnosis (p ≤ 0.001 and p = 0.03, respectively), and the bone resorption marker CTX‐I and TrAcP 5b increased. Postoperatively, the bone formation markers showed a three‐ to fourfold increase 1 year postoperatively, with a moderate decline thereafter. The bone resorption markers showed a similar but less pronounced course. This study shows that the phase immediately after surgical remission from endogenous CS is characterized by a high rate of bone turnover resulting in a striking net increase in bone mineral density in the majority of patients. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.

Introduction

Cushing’s syndrome (CS) is a rare disease with approximately 0.7 to 2.4 new cases per 1 million per year.1 Osteoporosis and osteopenia are typical comorbidities of patients with endogenous and exogenous CS. Depending on the study, 60% to 80% of patients have evidence for a reduced bone mineral density2 characteristically affecting the entire skeleton.3 About 5% of all cases of secondary osteoporosis are caused by hypercortisolism.4 However, data from prospective, well‐powered studies are rare, and few risk factors that would predict bone health have been identified so far. Guidelines for the management of osteoporosis due to endogenous CS are still missing.5 In terms of risk assessment, the subtype of CS does not seem to influence osteoporosis risk,6 whereas the morning cortisol levels are negatively correlated with lumbar bone mineral density.6 The duration of endogenous Cushing’s syndrome (or the duration of exogenous replacement therapy after successful surgery) obviously affects bone mineral density.7 Whether the T‐score is the best predictor for fracture risk is not quite clear.2

Another area of uncertainty is the natural course of osteoporosis and bone turnover markers once the diagnosis of Cushing’s syndrome has been established. A number of studies have addressed this topic, but the interpretation of the results is hampered because of limited patient numbers, concomitant osteoanabolic treatment, or both.810 In‐depth insight on bone remodeling in CS might come from bone turnover marker studies. For example, the bone formation marker osteocalcin is suppressed in untreated CS,3 a consistent observation making it useful as a diagnostic marker for CS.2

Based on the paucity of data, the lack of evidence for treatment guidelines, and the pressing open questions regarding risk assessment and management of osteoporosis, we performed a sufficiently powered study to analyze the natural course of bone turnover and bone mineral density in a monocentric cohort of patients with endogenous Cushing’s syndrome. To the best of our knowledge, this is the first such study, and the data obtained will be instrumental for clinicians who care for patients with Cushing’s syndrome.

Materials and Methods

Patients

This study was performed as part of the prospective German Cushing registry, which has included 450 consecutive patients referred to our department for suspected CS since 2012. Structure and general characteristics of the registry have been described in detail previously.1114 All patients included in the registry underwent a standardized biochemical screening and clinical examination at time of diagnosis and a yearly follow‐up after treatment to treat comorbidities and diagnose recurrence of the disease early.

In all patients, standard screening for CS with a 1 mg low‐dose overnight dexamethasone suppression test (LDDST), collection of 24‐hour urine (UFC), and sampling of midnight salivary cortisol were performed. When the diagnosis of CS was confirmed, further subtyping was based on plasma adrenocorticotropic hormone (ACTH), corticotropin‐releasing hormone (CRH) test, high‐dose dexamethasone suppression test, imaging, and inferior petrosal sinus sampling (in case of ACTH dependence). Final diagnosis was CS in 156 patients and exclusion of CS in the remaining 294 patients. Patients with excluded CS were a quite heterogenic group with lead symptoms such as obesity (73%), arterial hypertension (50%), or hirsutism (33%). Final diagnoses in these subjects were metabolic syndrome, polycystic ovary syndrome (PCOS), obesity, depression, or primary hyperaldosteronism. Patient selection is shown in Fig. 1.

image
Patient selection. *Very young age; patient conducted densitometry in a different clinic/outpatient clinic; patient refused densitometry. CS = Cushing’s syndrome; BMD = bone mineral density; BMI = body mass index. Bold text indicates actual cohort of the study.

In our analysis, we excluded patients for whom no densitometry data were available (n = 63) and patients receiving pharmacologic treatment for osteoporosis following diagnosis (n = 4). Densitometry data were not available for multiple reasons (very young age, external densitometry in a different clinic, missing consent to perform densitometry).

We matched the remaining 89 patients with 71 controls subjects selected from those subjects in whom CS was excluded. Matching was done according to sex, age, and body mass index (BMI). None of the patients and controls received specific osteoanabolic or antiresorptive treatment, but 47% of patients with CS received vitamin D supplementation after remission. At time of diagnosis, 11% of controls and 17% of patients with CS received vitamin D supplementation.

Methods

In patients with confirmed CS, a bone mineral densitometry was conducted. Bone mineral density (BMD) was determined at the lumbar spine and the femur (neck and total femur).

If a reduced bone mineral density was diagnosed, a follow‐up densitometry was performed 2 years after surgery. If bone mineral density was normal initially or during follow‐up, only one further densitometry was performed 2 or 3 years after initial diagnosis. An improvement or decrease of bone mineral density was defined according to the least significant change (LSC = 2.8 × 1.8%).15 Accordingly, an alteration of more than 5.04% of BMD was rated as significant. A detailed fracture history was taken and X‐ray of the spine was performed when clinical suspicion for fractures was high.

In all patients, blood samples (serum and plasma) were taken at time of diagnosis and also 1 and 2 years after successful transsphenoidal surgery or adrenalectomy. Blood was taken in the fasting state between 8:00 and 10:00 a.m. Samples were centrifuged within 20 minutes at 4°C and stored at −80° until assayed. Three bone formation markers and two bone resorption markers were measured: osteocalcin, intact procollagen I‐N‐propeptide (PINP), and bone alkaline phosphatase (BAP) as bone formation markers, and CrossLaps (CTX‐I) and tartrate‐resistant acid phosphatase (5b TrAcP5b) as bone resorption marker, on basis of published data demonstrating their usefulness in CS and primary osteoporosis.216

Samples were measured at the Endocrine Laboratory of the Department of Internal Medicine IV on the iSYS automated analyzer (IDS‐iSYS, Boldon, UK) by well‐validated assays.1718 Published, method‐specific reference intervals are available from a large healthy population.1920 For the determination of osteocalcin, an N‐MID assay was used, as pre‐analytics are less critical in this assay.21 TrAcp 5b is a new marker, which, in contrast to CTX‐1, can also reliably be measured in the non‐fasting state.22

Statistical analysis

In a priori power analysis, we calculated that a total sample size of 102 would be sufficient to identify significant differences between groups, assuming a medium effect size (0.5), a power of 1 – β = 0.80 and a type I error of α = 0.05, with 51 subjects having Cushing’s syndrome and 51 subjects being control subjects after excluding Cushing’s syndrome.

For statistical analysis, SPSS 25 (IBM Corp., Armonk, NY, USA) was used. Clinical characteristics are shown as mean and standard deviation when data is normal distributed; otherwise as median and ranges. Because of the lack of normal distribution of bone turnover markers, nonparametric tests were used to test differences between groups. Differences between bone turnover markers at different times were tested by Friedman test. Multiple regression analysis was used to investigate differences between CS and the control group regarding bone turnover markers adjusted for sex, age, and BMI. Any p values < 0.05 were considered to indicate statistical significance.

Results

Patient characteristics

The clinical and biochemical characteristics of the patient sample are summarized in Table 1. Sixty‐five percent of patients had pituitary CS, 28% adrenal, and 7% suffered from ectopic CS. Patients and controls were well‐matched regarding sex, age, and vitamin D levels and supplementation, but differed in terms of diabetes prevalence.

Table 1. Clinical and Biochemical Baseline Characteristics of Patients with Cushing’s Syndrome (CS) and Control Subjects in Whom CS Has Been Excluded
CS at time of diagnosis (n = 89) CS excluded (n = 71) p Value
Sex 66 women (74%), 23 men (26%) 53 women (75%), 18 men (25%) 0.94
Age (years) 44 ± 13 43 ± 14 0.56
BMI 30 ± 7 31 ± 6 0.11
Vitamin D (ng/mL) 24 ± 10 24 ± 12 0.59
Vitamin D supplementation 17% 11% 0.37
Diabetes mellitus 30% (26) 11% (7) 0.007
Morning serum cortisol (μg/dL) 18 (11.7–24.9) 8.4 (5.9–11.6) ≤0.001
LDDST (μg/dL) 14.7 (7.7–23.7) 1.0 (0.8–1.2) ≤0.001
UFC (μg/24 h) 587 (331–843) 140 (78–216) ≤0.001
ACTH (pg/mL) 47 (9–76) 13 (9–18) ≤0.001
Late‐night salivary cortisol (ng/mL) 7.9 (3.3–11.8) 1.2 (0.6–1.8) ≤0.001
Bone turnover markers
Osteocalcin (ng/mL) 8 (5–13) 13 (10–17) <0.001
PINP (ng/mL) 35 (29–62) 52 (35–73) 0.025
BAP (μg/L) 23 (16–31) 17 (14–24) 0.006
CTX‐I (ng/mL) 0.28 (0.17–0.42) 0.23 (0.12–0.32) 0.033
TrAcP (U/L) 2.3 (1.7–3.4) 1.9 (1.3–2.4) 0.009
  • Date are shown as mean ± standard deviation or median and ranges.
  • BMI = body mass index; LDDST = low‐dose dexamethasone suppression test; UFC = urinary free cortisol; ACTH = adrenocorticotropic hormone; PINP = intact procollagen I‐N‐propeptide; BAP = bone alkaline phosphatase; CTX‐I = CrossLaps; TrAcP = tartrate‐resistant acid phosphatase. Bold numbers indicate statistical significance.

Baseline evaluation

At time of diagnosis, the mean levels of bone formation markers osteocalcin and intact PINP were significantly decreased compared with the controls, and the bone formation marker bone alkaline phosphatase was increased (Table 1; Fig. 2). Both bone degradation markers CTX and TrAcP were increased (Table 1). Taken together, this demonstrates increased bone resorption and decreased bone formation in florid CS. Results of multiple linear regression analysis comparing Cushing’s syndrome patients and controls are shown in Table 2. Bone markers were similar in patients with a reduced bone mass versus those with a normal bone mass (data not shown).

image
Bone turnover markers and bone mineral density at baseline and 1 and 2 years after remission. Boxplot = median and ranges of bone turnover marker in patients with Cushing’s syndrome.Gray box = median and ranges of bone turnover markers in the control group.PINP = procollagen I‐N‐propeptide; BAP = bone alkaline phosphatase; TrAcP = tartrate‐resistant acid phosphatase; CTX‐I = CrossLaps.
Table 2. Results of Multiple Linear Regression Analysis Comparing Cushing’s Syndrome Patients Versus Controls
Dependent variable Standardized regression coefficient and p value for group variable
Unadjusted Adjusted for age, sex, and BMI
Osteocalcin (ng/mL) −0.392, 0.006 −0.375, 0.010
PINP (ng/mL) −0.215, 0.204 −0.256, 0.145
BAP (μg/L) 0.404, 0.001 0.470, <0.001
CTX‐I (ng/mL) 0.111, 0.366 0.065, 0.616
TrAcP (U/L) 0.227, 0.014 0.186, 0.069
  • PINP = procollagen I‐N‐propeptide; BAP = bone alkaline phosphatase; CTX‐I = CrossLaps; TrAcP = tartrate‐resistant acid phosphatase. Bold numbers indicate statistical significance.

Overall, bone mineral density was decreased with an average lowest T‐score of −1.4 (±1.1). BMD was significantly lower (p = 0.001) at the femoral neck (T‐score = −0.9 ± 1.0) and the spine (T‐score = −1.0 ± 1.5) compared with the total femur (T‐score = −0.5 ± 1.2). Twenty‐eight patients (32%) had a normal bone mineral density, 46 (52%) osteopenia, and the other 15 patients (17%) osteoporosis with a T‐score lower than −2.5.

Seventeen of the patients (19%) had a history of low‐trauma osteoporotic fractures (9 vertebral fractures, 8 nonvertebral fractures). The fractures took place shortly before diagnosis (58%) or more than 2 years before diagnosis of the CS (42%). Patients with osteoporotic fractures had a significantly lower T‐score than patients without fractures (T‐score = −1.9 ± 0.8 versus −1.3 ± 1.1, p = 0.03) but did not differ in the values of the bone turnover markers or standard biochemical screening. Subtype, age, or BMI also did not differ between groups. However, men were significantly at higher risk of having fractures than women (35% of men had fractures versus 14% of women, p = 0.03). Both severity of hypercortisolism and duration of CS did not contribute to fractures rates (data not shown), but UFC was significantly higher in patients with a T‐score lower than −1.5 (Table 3).

Table 3. Biochemical Markers in Patients With Cushing’s Syndrome With a T‐Score Lower Than −1.5 and Above −1.5 Shown in Median and Ranges
Variable T‐score < −1.5 (n = 39) T‐score ≥ −1.5 (n = 42) p Values
LDDST (μg/dL) 16.6. (10.3–28.3) 11.9 (6.1–21.9) 0.12
UFC (μg/24 h) 706 (410–906) 398 (285–787) 0.03
Late‐night salivary cortisol (ng/mL) 8.3 (3.5–13.6) 5.7 (2.9–11.7) 0.39
ACTH (pg/mL) 53 (16–73) 42 (6–82) 0.88
  • LDDST = low‐dose dexamethasone suppression test; UFC = urinary free cortisol; ACTH = adrenocorticotropic hormone. Bold numbers indicate statistical significance.

One‐ and 2‐year follow‐up

Surgical tumor resection leading to biochemical remission of CS resulted in a strong increase of bone formation markers tested at 1‐year follow‐up (Table 4; Fig. 2AB). After 2 years, the markers had decreased slightly but remained elevated. Bone resorption markers were mildly increased at time of diagnosis, increased further at 1 year post‐surgery, and returned almost to normal levels at 2 years (Table 4; Fig. 2DE). A follow‐up bone densitometry conducted in 40 patients showed a parallel increase of the T‐score of 0.6 ± 0.8 (Fig. 2F). In particular, BMD of the spine improved (Table 5).

Table 4. Bone Turnover Markers and Bone Mass in Patients With Cushing’s Syndrome at Time of Diagnosis and During 2 Years of Follow‐Up
Time of diagnosis (n = 50) 1 year in remission (n = 45) 2 years in remission (n = 38) p (0 versus 1) p (0 versus 2) p (1 versus 2)
T‐score −1.5 (−2.0 to −0.8) −1.1 (−1.5 to −0.4) <0.001
Osteocalcin (ng/mL) 8 (5–13) 30 (14–60) 21 (13–31) <0.001 0.008 0.3
PINP (ng/mL) 35 (29–62) 117 (52–221) 69 (46–113) <0.001 0.1 0.1
BAP (μg/L) 23 (16–31) 26 (19–38) 22 (15–31) 0.2 0.4 0.1
CTX‐I (ng/mL) 0.28 (0.17–0.42) 0.51 (0.22–0.91) 0.25 (0.18–0.73) 0.01 0.1 0.04
TrAcP (U/L) 2.3 (1.7–3.4) 2.8 (1.8–4.0) 2.3 (2–3.2) 0.1 0.6 0.002
  • PINP = procollagen I‐N‐propeptide; BAP = bone alkaline phosphatase; CTX‐I = CrossLaps; TrAcP = tartrate‐resistant acid phosphatase. Bold numbers indicate statistical significance.
Table 5. Overview: T‐Scores, Z‐Scores, and BMD Values With Percent Changes (Mean and Standard Deviation)
Variable CS at time of diagnosis CS 2 years in remission p Values, percent changes (↑)
Femoral neck
T‐score femoral neck −0.81 ± 0.97 −0.59 ± 0.86 0.06
Z‐score femoral neck −0.59 ± 0.98 −0.28 ± 0.79 0.02
BMD (g/cm2) femoral neck 0.91 ± 0.12 0.95 ± 0.12 0.16; 4% ↑
Femur
T‐score femur −0.49 ± 1.11 −0.42 ± 1.04 0.67
Z‐score femur −0.40 ± 1.04 −0.37 ± 0.85 0.31
BMD (g/cm2) femur 0.95 ± 0.15 0.97 ± 0.14 0.77, 2% ↑
Spine
T‐score spine −0.96 ± 1.56 −0.55 ± 1.25 <0.001
Z‐score spine −0.85 ± 1.53 −0.58 ± 1.14 <0.001
BMD (g/cm2) spine 1.08 ± 0.22 1.13 ± 0.15 0.001, 0.6% ↑
  • BMD = bone mineral density; CS = Cushing’s syndrome. Bold numbers indicate statistical significance.

In 78% of patients, bone mineral density improved after 2 years; in 45% of patients, T‐score improved more than 0.5. No clinical fractures occurred after successful treatment of the CS. There was no significant correlation between improvement of bone mineral density and any of the bone turnover markers.

Discussion

This study investigated for the first time to our knowledge a panel of bone formation and resorption markers in a large cohort of patients with CS over the long term. The unique and comprehensive data show that initially bone metabolism is characterized by decreased bone formation and increased bone resorption, in line with the classical action of glucocorticoids. Successful treatment of endogenous Cushing’s syndrome leads to a strong activation of bone turnover, characterized by increased bone formation and bone resorption, a process that is continuous beyond year 2 after remission of CS, although at a reduced activity level. In parallel, bone mineral density increases in the majority of patients. Although 19% had low‐trauma fractures at baseline, none of the subjects experienced clinical fractures during follow‐up. In summary, these data give new insight into bone healing after remission of CS. They strongly suggest that an observational approach to the bone phenotype is justified as long as remission from CS is secured.

Reversibility of osteoporosis and bone turnover markers

Although established in osteoporosis research, bone turnover markers are not measured on a routine basis in patients with CS. However, it is a consistent result from different studies that osteocalcin is depressed in patients with CS. In fact, this finding is so reliable that it was even suggested to use osteocalcin in the diagnosis of CS.2 P1NP and procollagen carboxy‐terminal propeptide (P1CP) have also been studied in several studies, with contradictory results.23 In a retrospective study with 21 patients with CS, it was shown that osteocalcin is depressed; this applies also for PINP, whereas CTX is increased.24

Some studies already have focused on the reversibility of osteoporosis after treatment of CS. In the majority of patients, bone mineral density increased within 2 years after successful treatment81025 Hermus and colleagues showed in a study with 20 patients that bone mineral density did not change 3 or 6 months after surgery but increased thereafter in almost all patients.8 In a study with 68 patients, the patients were followed up for 4 years. Bone mineral density increased over lumbar spine and femur but decreased at the forearm.25 The authors concluded that bone minerals were redistributed from the peripheral to the axial skeleton.

In our study, bone mineral density also improved in the majority of patients but remained reduced in some. We did not find any difference in bone turnover markers between patients with improvement and without improvement.

Current treatment guidelines and treatment suggestions

As observed in our study, bone formation markers increase significantly after surgical cure, whereas bone degradation markers are mildly elevated at baseline and increase slightly at 1 year, returning within the normal range at 2 years. So far, there is no international guideline on the treatment of osteoporosis induced by endogenous CS and very few controlled interventional studies. In an opinion paper, Scillitani and colleagues recommended to treat all patients with vitamin D and calcium but not with bisphosphonates.5 In a randomized open‐label study by Di Somma and colleagues,26 39 patients (18 patients with active CS and 21 patients with CS in remission) received alendronate or no medication. Patients with active CS also received ketoconazole to control hypercortisolism. Bone mineral density improved and serum levels of osteocalcin increased in patients who received alendronate to a greater extent than those receiving no alendronate.

In a small study by the same research group,27 15 patients with CS (9 adolescent patients and 6 adults) were observed for 2 years after successful treatment, showing that osteocalcin levels and bone mineral density increased significantly.

Strengths and limitations

Although this study has several strengths, including the large prospective design and measuring a panel of bone formation and resorption markers, there are a few limitations. Some asymptomatic fractures may have been overlooked because an X‐ray was not taken systematically in each patient. Furthermore, a follow‐up bone densitometry was not available for all patients. Additionally, patients in the control group suffered from diabetes, overweight, arterial hypertension, or other diseases.

Novel aspects and outlook

This study analyzes for the first time in a comprehensive way bone turnover markers during the course of CS. The data show that cure from CS leads to increases in bone remodeling and bone mineral density, in line with spontaneous “bone healing.” Our data support a wait‐and‐watch strategy despite a high endogenous risk for additional fractures, based on the baseline assessment. This observation will influence future therapeutic strategies in patients with CS.

Our data suggest that the phase immediately after remission from CS is characterized by a high rate of bone turnover, resulting in a spontaneous net increase in bone mineral density in the majority of patients. Both bone attachment and bone degradation markers increase significantly, leading to an increase in bone mass and to a reduced risk of osteoporotic fractures. This unconstrained increase in bone formation markers after remission should be considered before specific therapy is initiated. Our data do not favor specific pharmacologic interventions with bisphosphonates or denosumab during this phase of remodeling because they may disrupt the osteoblast‐mediated bone mass increase.

Disclosures

All authors state that they have no conflicts of interest.

Acknowledgments

This work is part of the German Cushing’s Registry CUSTODES and has been supported by a grant from the Else Kröner‐Fresenius Stiftung to MR (2012_A103 and 2015_A228). Additionally, AR, FB, and MR received funding by the Deutsche Forschungsgemeinschaft (CRC/TRR 205/1 “The Adrenal Gland”). Furthermore, funds for this project were provided by the Verein zur Förderung von Wissenschaft und Forschung an der Medizinischen Fakultät der Ludwig‐Maximilians‐Universität München eV to LB.

The data are stored on the following repository: https://figshare.com/ and will be made accessible after publication of the article.

Authors’ roles: LB served as the principal investigator in this work and was responsible for the study conception and design, the analysis and interpretation of the data, and the drafting of the manuscript. JF, SZ, AO, AR, GR and SB contributed to the collection and analysis of the data. MS, FB, MD, MB substantially contributed to the interpretation of the data and the drafting of the manuscript. RS contributed to the conceptual design of the study, the interpretation of data and the revision of the paper. MR contributed to the conceptual design of the study, the collection, analysis and interpretation of data, and the drafting and revision of the paper. All authors contributed to the critical revision of the manuscript and approved the final version for publication.

From https://asbmr.onlinelibrary.wiley.com/doi/full/10.1002/jbmr.4033

Cortisol Levels Predict Remission in Cushing’s Patients Undergoing Transsphenoidal Surgery

In patients with Cushing’s disease, removing the pituitary tumor via an endoscopic transsphenoidal surgery (TSS) leads to better remission rates than microscopic TSS, according to new research.

But regardless of surgical approach, plasma cortisol levels one day after surgery are predictive of remission, researchers found.

The study, “Management of Cushing’s disease: Changing trend from microscopic to endoscopic surgery,” was published in the journal World Neurosurgery.

Because it improves visualization and accessibility, endoscopic TSS has been gaining popularity over microscopic TSS to remove pituitary tumors in Cushing’s disease patients. Yet, although this surgery has been associated with high remission rates, whether it outperforms microscopic surgery and determining the factors affecting long-term outcomes may further ease disease recurrence after TSS.

A team with the All India Institute of Medical Sciences addressed this topic in 104 patients who underwent surgery from January 2009 to June 2017. Among these patients, 47 underwent microscopic surgery and 55 endoscopic surgery. At presentation, their ages ranged from 9 to 55 (mean age of 28). Also, patients had been experiencing Cushing’s symptoms over a mean duration of 24 months.

Eighty-seven patients showed weight gain. Hypertension (high blood pressure) and diabetes mellitus were among the most common co-morbidities, found in 76 and 33 patients, respectively. Nineteen patients had osteoporosis and 12 osteopenia, which refers to lower-than-normal bone mineral density.

As assessed with magnetic resonance imaging, 68 patients had a microadenoma (a tumor diameter smaller than one centimeter) and 27 had a macroadenoma (a tumor one centimeter or larger). Only two patients had an invasive pituitary adenoma.

Two patients with larger tumors were operated on transcranially (through the skull). The surgery resulted in total tumor removal in 90 cases (86.5%). A blood loss greater than 100 milliliter was more common with endoscopic than with microscopic TSS.

Ten patients developed transient diabetes inspidus, two experienced seizures after surgery, and six of nine patients with macroadenoma and visual deterioration experienced vision improvements after TSS.

The incidence of intraoperative leak of cerebrospinal fluid — the liquid surrounding the brain and spinal cord — was 23.2%, while that of post-operative leak was 7.7% and was more common in microadenoma than macroadenoma surgery (9.8% vs. 5.0%).

Seventeen patients were lost to follow-up and two died due to metabolic complications and infections. The average follow-up was shorter for endoscopic than with microscopic surgery (18 months vs. 35 months).

Among the remaining 85 cases, 65 (76.5%) experienced remission, as defined by a morning cortisol level under 5.0 μg/dL, restored circadian rhythm (the body’s internal clock, typically impaired in Cushing’s patients), and suppression of serum cortisol to below 2 μg/dl after overnight dexamethasone suppression test.

The remission rate was 54.5% in pediatric patients and was higher with endoscopic than with microscopic TSS (88.2% vs. 56.6%). Also, patients with microadenoma showed a trend toward more frequent remission than those with macroadenoma (73.2% vs. 64.3%).

Ten of the remaining 20 patients experienced disease recurrence up to 28 months after surgery. Sixteen cases revealed signs of hypopituitarism, or pituitary insufficiency, which were managed with replacement therapy.

A subsequent analysis found that morning cortisol level on day one after surgery was the only significant predictor of remission. Specifically, a one-unit increase in cortisol lowered the likelihood of remission by 7%. A cortisol level lower than 10.7 μgm/dl was calculated as predicting remission.

Overall, the study showed that “postoperative plasma cortisol level is a strong independent predictor of remission,” the researchers wrote, and that “remission provided by endoscopy is significantly better than microscopic approach.”

From https://cushingsdiseasenews.com/2019/09/24/cortisol-levels-predict-remission-cushings-patients-undergoing-transsphenoidal-surgery/

Metoclopramide Can Mask Adrenal Insufficiency After Gland Removal in BMAH Patients

Metoclopramide, a gastrointestinal medicine, can increase cortisol levels after unilateral adrenalectomy — the surgical removal of one adrenal gland — and conceal adrenal insufficiency in bilateral macronodular adrenal hyperplasia (BMAH) patients, a case report suggests.

The study, “Retention of aberrant cortisol secretion in a patient with bilateral macronodular adrenal hyperplasia after unilateral adrenalectomy,” was published in Therapeutics and Clinical Risk Management.

BMAH is a subtype of adrenal Cushing’s syndrome, characterized by the formation of nodules and enlargement of both adrenal glands.

In this condition, the production of cortisol does not depend on adrenocorticotropic hormone (ACTH) stimulation, as usually is the case. Instead, cortisol production is triggered by a variety of stimuli, such as maintaining an upright posture, eating mixed meals — those that contain fats, proteins, and carbohydrates — or exposure to certain substances.

A possible treatment for this condition is unilateral adrenalectomy. However, after the procedure, some patients cannot produce adequate amounts of cortisol. That makes it important for clinicians to closely monitor the changes in cortisol levels after surgery.

Metoclopramide, a medicine that alleviates gastrointestinal symptoms and is often used during the postoperative period, has been reported to increase the cortisol levels of BMAH patients. However, the effects of metoclopramide on BMAH patients who underwent unilateral adrenalectomy are not clear.

Researchers in Japan described the case of a 61-year-old postmenopausal woman whose levels of cortisol remained high after surgery due to metoclopramide ingestion.

The patient was first examined because she had experienced high blood pressure, abnormal lipid levels in the blood, and osteoporosis for ten years. She also was pre-obese.

She was given medication to control blood pressure with no results. The lab tests showed high serum cortisol and undetectable levels of ACTH, suggesting adrenal Cushing’s syndrome.

Patients who have increased cortisol levels, but low levels of ACTH, often have poor communication between the hypothalamus, the pituitary, and the adrenal glands. These three glands — together known as the HPA axis — control the levels of cortisol in healthy people.

Imaging of the adrenal glands revealed they were both enlarged and presented nodules. The patient’s cortisol levels peaked after taking metoclopramide, and her serum cortisol varied significantly during the day while ACTH remained undetectable. These results led to the BMAH diagnosis.

The doctors performed unilateral adrenalectomy to control cortisol levels. The surgery was successful, and the doctors reduced the dose of glucocorticoid replacement therapy on day 6.

Eight days after the surgery, however, the patient showed decreased levels of fasting serum cortisol, which indicated adrenal insufficiency — when the adrenal glands are unable to produce enough cortisol.

The doctors noticed that metoclopramide was causing an increase in serum cortisol levels, which made them appear normal and masked the adrenal insufficiency.

They stopped metoclopramide treatment and started replacement therapy (hydrocortisone) to control the adrenal insufficiency. The patient was discharged 10 days after the surgery.

The serum cortisol levels were monitored on days 72 and 109 after surgery, and they remained lower than average. Therefore she could not stop hydrocortisone treatment.

The levels of ACTH remained undetectable, suggesting that the communication between the HPA axis had not been restored.

“Habitual use of metoclopramide might suppress the hypothalamus and pituitary via negative feedback due to cortisol excess, and lead to a delayed recovery of the HPA axis,” the researchers said.

Meanwhile, the patient’s weight decreased, and high blood pressure was controlled.

“Detailed surveillance of aberrant cortisol secretion responses on a challenge with exogenous stimuli […] is clinically important in BMAH patients,” the study concluded. “Caution is thus required for assessing the actual status of the HPA axis.”

From https://cushingsdiseasenews.com/2019/05/07/metoclopramide-conceals-adrenal-insufficiency-after-gland-removal-bmah-patients-case-report/

Mild Cases of Cushing’s Syndrome Present Diagnostic Challenges

By Tori Rodriguez, MA, LPC

 

In the early 20th century, the term “pluriglandular syndrome” was coined by Harvey Cushing to describe the disorder that results from chronic tissue exposure to excessive levels of glucocorticoids.1 Now called Cushing’s syndrome, the condition affects an estimated 10-15 million people annually, most often women and individuals between the ages of 20 and 50 years.2 Risk factors and common comorbidities include hypertension, obesity, osteoporosis, uncontrolled diabetes, depression, and anxiety.3

Presentation

The clinical presentation of the disorder is heterogenous and varies by sex, age, and disease severity. Common signs and symptoms include central adiposity, roundness of the face or extra fat around the neck, thin skin, impaired short-term memory and concentration, irritability, hirsutism in women, fatigue, and menstrual irregularity.4 Because each of these features may be observed in a wide range of other conditions, it may be difficult to diagnose cases that are not severe.

“It can be challenging to differentiate the milder forms from pseudo-Cushing’s states,” which are characterized by altered cortisol production and many of the same clinical features as Cushing’s syndrome, according to Roberto Salvatori, MD, the medical director of the Johns Hopkins Pituitary Center, Baltimore, Maryland. These may include alcoholism, obesity, eating disorders, and depression. “Because Cushing’s can cause depression, for example, it is sometimes difficult to determine which came first,” he says. In these states, however, hypercortisolism is believed to be driven by increased secretion of hypothalamic corticotropin-releasing hormone, which is suppressed in Cushing’s syndrome.5

Causes and Diagnosis

If Cushing’s syndrome is suspected on the basis of the patient’s physical appearance, the diagnostic workup should include a thorough medical history, physical exam, and 1 or more of the following tests to establish hypercortisolism: the 24-hour urinary cortisol test, the low-dose dexamethasone suppression test, or the late-night salivary cortisol test. “We sometimes use 2 or 3 of these tests since 1 may not accurately reflect cortisol production in a particular patient,” Dr Salvatori notes. The next step is to determine the source of the hypercortisolism, which may involve the high-dose dexamethasone suppression test, magnetic resonance imaging, or petrosal sinus sampling.2

Medication is the most common cause of Cushing’s syndrome. These iatrogenic or exogenous cases typically result from corticosteroids administered for conditions such as asthma, allergies, and autoimmune disorders.6 More rarely, the disorder can be caused by the use of medroxyprogesterone. In these cases, corticosteroids should be reduced or discontinued under medical care, if possible.

Endogenous Cushing’s syndrome results from the presence of benign or malignant tumors on the adrenal or pituitary glands or elsewhere in the body. These tumors can interfere with the adrenal glands’ production of cortisol that is usually prompted by the adrenocorticotropic hormone (ACTH) released by the pituitary gland.6 There are 3 different mechanisms by which the process can occur.

  • Pituitary adenomas, which account for approximately 70% of endogenous cases of Cushing’s syndrome, secrete ACTH and stimulate additional cortisol production. Because of the large proportion of cases this condition represents, it is specifically referred to as Cushing’s disease. It is more common in women than men (with a ratio of 3 to 4:1), although in pediatric patients, it occurs more frequently in boys vs girls.5
  • Adrenal tumors (adenomas, malignant tumors, or micronodular hyperplasia) produce cortisol in their own tissue in addition to the amount produced by the adrenal glands. These tumors, which cause approximately 15% of endogenous Cushing’s syndrome cases, are more common in children vs adults and in women vs men.
  • Benign or malignant tumors elsewhere in the body, most often the lungs, thyroid, thymus, and pancreas, secrete ACTH and trigger the excessive release of cortisol. An estimated 15% of endogenous cases are attributed to these types of tumors.

Treatment

Surgery is the first-line treatment for Cushing’s syndrome. “We first want to try to figure out the cause of the disorder,” Dr Salvatori says. “Ideally, treatment involves surgery to remove the tumor that is causing it.”

When surgery is unsuccessful, contraindicated, or delayed, other treatment options include radiation or medications that inhibit cortisol, modulate the release of ACTH, or inhibit steroidogenesis.5 Bilateral adrenalectomy may be indicated for patients who do not respond to medication or other surgery.

If surgical resection of the tumor is successful, then “all of the comorbidities reverse, but if it is unsuccessful or must be delayed, you would treat each comorbidity” with the appropriate medication; for example, antihypertensives for high blood pressure and antidiabetic medications for diabetes, Dr Salvatori advises. In severe cases, prophylactic antibiotics may be indicated for the prevention of severe infections such as pneumonia.

It is also important to inquire about and address psychiatric symptoms related to Cushing’s syndrome, even in patients who are in remission. It has been proposed that the chronic hypercortisolism and dysfunction of the HPA axis may “lead to structural and functional changes in the central nervous system, developing brain atrophy, particularly in the hippocampus, which may determine the high prevalence of psychiatric disorders, such as affective and anxiety disorders or cognitive dysfunctions,” according to a recently published paper on the topic.7 Patients should be screened with self-report questionnaires such as the Beck Depression Inventory and the Hospital Anxiety and Depression Scale, and management of psychiatric symptoms may include patient education, psychotropic medications, and referral to a mental health professional.

Future Directions

Several trials are currently planned or underway, including a phase 2 randomized, double-blind, placebo-controlled study of an oral medication called ATR-101 by Millendo Therapeutics, Inc. (ClinicalTrials.gov identifier: NCT03053271). In addition to the need for novel medical therapies, refined imaging techniques could improve surgical success rates in patients with Cushing’s disease in particular, according to Dr Salvatori. “A significant portion of these patients have tumors too small to be detected by MRI, and the development of more sensitive MRI could improve detection and provide a surgical target” for neurosurgeons treating the patients, he says.

Summary

Milder cases of Cushing’s syndrome present diagnostic challenges are a result overlapping features with various other conditions. Diagnosis may require careful observation as well as biochemical and imaging tests.

References

  1. Loriaux DL. Diagnosis and differential diagnosis of Cushing’s syndromeN Engl J Med. 2017;376:1451-1459. doi:10.1056/NEJMra1505550
  2. American Association of Neurological Surgeons. Cushing’s syndrome/disease. http://www.aans.org/Patients/Neurosurgical-Conditions-and-Treatments/Cushings-Disease. Accessed August 1, 2017.
  3. León-Justel A, Madrazo-Atutxa A, Alvarez-Rios AI, et al. A probabilistic model for cushing’s syndrome screening in at-risk populations: a prospective multicenter studyJ Clin Endocrinol Metab. 2016;101:3747-3754. doi:10.1210/jc.2016-1673
  4. The Pituitary Society. Cushing’s syndrome and disease–symptoms. https://pituitarysociety.org/patient-education/pituitary-disorders/cushings/symptoms-of-cushings-disease-and-cushings-syndrome. Accessed August 1, 2017.
  5. Sharma ST, Nieman LK, Feelders RA. Cushing’s syndrome: epidemiology and developments in disease managementClin Epidemiol. 2015;7:281-293. doi:10.2147/CLEP.S44336
  6. National Institutes of Health: Eunice Kennedy Shriver National Institute of Child Health and Human Development. What causes Cushing’s syndrome?https://www.nichd.nih.gov/health/topics/cushing/conditioninfo/pages/causes.aspx. Accessed August 1, 2017.
  7. Santos A, Resmini E, Pascual JC, Crespo I, Webb SM. Psychiatric symptoms in patients with Cushing’s syndrome: prevalence, diagnosis and management. Drugs. 2017;77:829-842. doi:10.1007/s40265-017-0735-z

From http://www.endocrinologyadvisor.com/adrenal/cushings-syndrome-diagnosis-treatment/article/682302/