Thyroid dysfunction highly prevalent in Cushing’s syndrome

Central hypothyroidism is prevalent in about 1 in 2 adults with Cushing’s syndrome, and thyroid function can be restored after curative surgery for most patients, according to study findings.

“Our study findings have confirmed and greatly extended previous smaller studies that suggested a link between hypercortisolism and thyroid dysfunction but were inconclusive due to smaller sample size and short follow-up,” Skand Shekhar, MD, an endocrinologist and clinical investigator in the reproductive physiology and pathophysiology group at the National Institute of Environmental Health Sciences, NIH, told Healio. “Due to our large sample and longer follow-up, we firmly established a significant negative correlation between hypercortisolemia measures — serum and urinary cortisol, serum adrenocorticotropic hormone — and thyroid hormones triiodothyronine, free thyroxine and thyrotropin.”

Shekhar and colleagues conducted a retrospective review of two groups of adults aged 18 to 60 years with Cushing’s syndrome. The first group was evaluated at the NIH Clinical Center from 2005 to 2018 (n = 68; mean age, 43.8 years; 62% white), and the second group was evaluated from 1985 to 1994 (n = 55; mean age, 37.2 years; 89% white). The first cohort was followed for 6 to 12 months to observe the pattern of thyroid hormone changes after surgical cure of adrenocorticotropic hormone-dependent Cushing’s syndrome. The second group underwent diurnal thyroid-stimulating hormone evaluation before treatment and during remission for some cases.

Urinary free cortisol and morning thyroid hormone levels were collected for all participants. In the second group, researchers evaluated diurnal patterns of TSH concentrations with hourly measurements from 3 to 7 p.m. and midnight to 4 p.m. In the first group, adrenocorticotropic hormone and serum cortisol were measured.

In the first cohort, seven participants were receiving levothyroxine for previously diagnosed primary or central hypothyroidism. Of the remaining 61 adults, 32 had untreated central hypothyroidism. Thirteen participants had free T4 at the lower limit of normal, and 19 had subnormal levels. There were 29 adults with subnormal levels of T3 and seven with subnormal TSH.

Before surgery, 36 participants in the first group had central hypothyroidism. Six months after surgery, central hypothyroidism remained for 10 participants. After 12 months, the number of adults with central hypothyroidism dropped to six. Preoperative T3 and TSH levels were negatively associated with morning and midnight cortisol, adrenocorticotropic hormone and urinary free cortisol. In post hoc analysis, a baseline urinary free cortisol of more than 1,000 g per day was adversely associated with baseline and 6-month T3 and free T4 levels.

In the second group, there were 51 participants not on thyroid-modifying drugs who had a thyroid function test 6 or 12 months after surgery. Before surgery, free Tlevels were subnormal in 17 participants, T3 levels were subnormal in 22, and TSH levels were in the lower half of the reference range or below in all but one participant.

After surgery, two participants had below normal free T4, one had subnormal T3, and TSH levels were in the lower half of the reference range or below in 23 of 48 participants. Before surgery, there was no difference in mean TSH between daytime and nighttime. A mean 8 months after surgery, the second group had a normal nocturnal TSH surge from 1.3 mIU/L during the day to 2.17 mIU/L at night (P = .01). The nocturnal TSH increase persisted as long as 3 years in participants who had follow-up evaluations.

“We found a very high prevalence of thyroid hormone deficiency that appears to start at the level of the hypothalamus-pituitary gland and extend to the tissue level,” Shekhar said. “Some of these patients may experience thyroid hormone deficiency symptoms, such as fatigue, depression, cold intolerance, weight gain, etc, as a result of systematic and tissue-level thyroid hormone deficiency. We also noted a strong correlation between hypothyroidism and hypogonadism, which implies that hypothyroid patients are also likely to suffer adverse reproductive effects. Thus, it is imperative to perform thorough thyroid hormone assessment in patients with Cushing’s syndrome, and thyroid hormone supplementation should be considered for these patients unless cure of Cushing’s syndrome is imminent.”

Researchers said providers should routinely screen for hypothyroidism in adults with Cushing’s syndrome. Even after thyroid function is restored, regular follow-up should also be conducted.

Further research is needed to investigate thyroid dysfunction in iatrogenic Cushing’s syndrome and the impact of these findings on euthyroid sick syndrome, Shekhar said.

For more information:

Skand Shekhar, MD, can be reached at skand.shekhar@nih.gov.

From https://www.healio.com/news/endocrinology/20210208/thyroid-dysfunction-highly-prevalent-in-cushings-syndrome

Treatment for Rare Cancer May Help Cushing’s Patients

The cancer medicine bexarotene may hold promise for treating Cushing’s disease, a study suggests.

The study, “Targeting the TR4 nuclear receptor with antagonist bexarotene can suppress the proopiomelanocortin signalling in AtT‐20 cells,” was published in the Journal of Cellular and Molecular Medicine.

Cushing’s disease is caused by a tumor on the pituitary gland, leading this gland to produce too much adrenocorticotropic hormone (ACTH). Excess ACTH causes the adrenal glands to release too much of the stress hormone cortisol; abnormally high cortisol levels are primarily responsible for the symptoms of Cushing’s.

Typically, first-line treatment is surgical removal of the pituitary tumor. But surgery, while effective in the majority of cases, does not help all. Additional treatment with medications or radiation therapy (radiotherapy) works for some, but not others, and these treatments often have substantial side effects.

“Thus, the development of new drugs for CD [Cushing’s disease] treatment is extremely urgent especially for patients who have low tolerance for surgery and radiotherapy,” the researchers wrote.

Recent research has shown that a protein called testicular receptor 4 (TR4) helps to drive ACTH production in pituitary cancers. Thus, blocking the activity of TR4 could be therapeutic in Cushing’s disease.

Researchers conducted computer simulations to screen for compounds that could block TR4. This revealed bexarotene as a potential inhibitor. Further biochemical tests confirmed that bexarotene could bind to, and block the activity of, TR4.

Bexarotene is a type of medication called a retinoid. It is approved to treat cutaneous T-cell lymphoma, a rare cancer that affects the skin, and available under the brand name Targretin.

When pituitary cancer cells in dishes were treated with bexarotene, the cells’ growth was impaired, and apoptosis (a type of programmed cell death) was triggered. Bexarotene treatment also reduced the secretion of ACTH from these cells.

In mice with ACTH-secreting pituitary tumors, bexarotene’s use significantly reduced tumor size, and lowered levels of ACTH and cortisol. Cushing’s-like symptoms also eased; for example, bexarotene treatment reduced the accumulation of fat around the abdomen in these mice.

Additional cellular experiments suggested that bexarotene specifically works on TR4 by changing the location of the protein. Normally, TR4 is present in the nucleus — the cellular compartment that houses DNA — where it helps to control the production of ACTH.

But with bexarotene treatment, TR4 tended to go outside of the nucleus, leading to lower ACTH production. The researchers noted that other mechanisms may also be involved in the observed effects of bexarotene.

“In summary, our work demonstrates that bexarotene is a potential inhibitor for TR4. Importantly, bexarotene may represent a new drug candidate to treat CD,” the researchers concluded.

Cushing’s syndrome in a child

Abstract

Cushing’s syndrome is a rare entity in children. Adrenal tumour is the common cause of this syndrome in young children, whereas, iatrogenic causes are more common among older children. We report a 4 year old male child diagnosed with Cushing syndrome due to a right adrenal adenoma; the child presented with obesity and increase distribution of body hair. After thorough investigation and control of hypertension and dyselectrolytemia, right adrenalectomy was performed. The patient had good clinical recovery with weight loss and biochemical resolution of Cushing’s syndrome.

1. Introduction

Cushing’s syndrome (CS) is rarely encountered in children. The overall incidence of Cushing syndrome is approximately 2–5 new cases per million people per year. Only approximately 10% of the new cases each year occur in children [1]. Unlike in adults, a male-to-female predominance have been observed in infants and young toddlers [[1][2][3]]. Although iatrogenic causes are common in children above seven years of age, adrenal causes (adenoma, carcinoma or hyperplasia) are common in children of younger age [4]. We report a 4 year old boy diagnosed with Cushing syndrome caused by a right adrenal adenoma, who had presented with obesity and increase distribution of body hair. Right adrenalectomy was performed and clinical stabilization resulted in weight loss and biochemical resolution of Cushing’s syndrome. (see Fig. 5)

2. Case report

A 4 years old boy presented with complaints of excessive weight gain of 5 months duration and increase frequency of micturition and appearance of body hair for 4 months. There was no history of any other illness, medication or steroid intake. The child was first born at term by normal vaginal delivery and birth weight of 3 kg. Physical examination revealed a chubby boy with moon face, buffalo hump, protruding abdomen, increase body hair and appearance of coarse pubic hair (Fig. 1). His intelligent quotient (IQ) was appropriate for his age and sex. His younger sibling was in good health and other family members did not have any metabolic or similar problems.

Fig. 1

Fig. 1. The child with moon face, protruded abdomen and coarse body hair.

The patient’s body length was 92cm (between -2SD to -3SD), weight 20kg (between 1 SD and 2 SD), weight for height >3SD, and BMI was 23.6 (BMI for age >3 SD). His blood pressure on right arm in lying position was 138/76 mm Hg (above 99th percentile for height and age).

Investigations: Morning 8am serum cortisol level – 27.3 μg/dl (normal: 6–23 μg/dl).

with a concurrent plasma ACTH level of < 5 pg/ml (n value < 46 pg/ml).

His serum cortisol following low dose dexamethasone suppression test (1mg dexamethasone at 11pm) at 8 am next morning was 22.1 μug/dl and his 24 hours urine catecholamine fraction was within normal limit.

HB % — 10.3 gm/dl; LDDST — 25 μg/dl; FBS — 106 mg/dl.

Serum Na+ – 140.6mmol/l; K+ – 2.83mmol/l; Ca+ – 8.7 mg/dl.

S. Creatinine −0.3 mg/dl.

Ultrasonography of abdomen revealed a heterogenous predominantly hypoechoic right supra renal mass. Contrast enhanced CT abdomen revealed well defined soft tissue density lesion (size −5.2 cm × 5.2 cm x 5.7cm) in right adrenal gland with calcifications and fat attenuations showing mild attenuation on post contrast study (Fig. 2).

Fig. 2

Fig. 2. CECT shows right adrenal mass with calcification and mild attenuation on post-contrast study.

The child was started on oral amlodipine 2.5mg 12hourly; after 5days blood pressure became normal. For hypokalemia oral potassium was given @20 meq 8 hourly and serum potassium value became normal after 4 days. Right laparoscopic adrenalectomy was planned. but due to intra operative technical problems it was converted to an open adrenalectomy with right subcostal incision. A lobulated mass of size 9 cm × 5 cm x 4 cm with intact capsule was excised. The tumour weighed 230 gm. There was no adhesion with adjacent organs, three regional nodes were enlarged but without any tumour tissue. Inferior vena cava was spared. Histopathology report was consistent with adrenal adenoma (Fig. 3) (see Fig. 4).

Fig. 3

Fig. 3. Cut section of tumour shows fleshy mass with fatty tissue.

Fig. 4

Fig. 4. Microphotograph (100 × 10) showing intact capsule and adrenal tumour cells, which are larger in size with nuclear pleomorphism, inconspicuous nucleoli, cytoplasm of the tumour cells are abundant, eosinophilic and vacuolated.

Fig. 5

Fig. 5. Physical appearance 4 months after adrenalectomy.

Post operative management: during post operative period hypokalemia and flaxuating blood sugar level was managed with oral potassium and oral glucose supplement. patient developed mild cough and respiratory distress on post op day 2, it was managed with salbutamol nebulization and respiratory physio therapy. Patient developed minor ssi and discharged on 10 th post operative day with oral prednisolone supplementation.

Follow up: the patient was followed up 2week after discharge and then every monthly, the oral prednisolone was gradually tapered and completely withdrawn on 2nd month after surgery.The patient experienced no post-surgical complications. After 4 months of surgery he reduces 6 kgs of his body weight with BMI of 16.5 (between median and 1SD) & BP 100/74 mm hg (within normal range), the moon face, buffalo hump, central obesity disappeared, morning 8am serum cortisol level was found within normal range 14 μg/dl (n value 6–23 μg/dl).

3. Discussion

Cushing’s syndrome is caused by prolonged exposure to supraphysiological levels of circulating glucocorticoids, which may be endogenously or exogenously derived. During infancy, CS is usually associated with McCune-Albright syndrome; adrenocortical tumours most commonly occur in children under four years of age and Cushing’s disease (ACTH dependent) is the commonest cause of CS after five years of age [5]. Primary adrenocortical tumours (ACTs) account for only 0.3–0.4% of all childhood neoplasms. Almost a third of these tumours manifests as Cushing syndrome and over 70% of the unilateral tumours in young children are often malignant [2,3,6,7]. There seems to be a bimodal incidence of these tumours, with one peak at under 5 years of age and the second one in the fourth or fifth decades of life. ACTs may be associated with other syndromes, such as, Li-Fraumeni syndrome, Beckwith-wiedemann syndrome, isolated hemihypertrophy, or even a germline point mutation of P53 tumour suppressor gene as reported in a series from Brazil [8]. In comparison to adult CS, growth failure with associated weight gain is one of the most reliable indicators of hypercortisolaemia in pediatric CS. The parents often fail to notice facial changes and growth failure and hence the diagnosis is often delayed. In one study, the mean time from appearing symptoms to diagnosis in 33 children with Cushing’s disease was 2.5 years [5]. More recently the comparison of height and BMI SDS measurements provided a sensitive diagnostic discriminator in pediatric patients with CD and those with simple obesity [9]. In the present case, the parents observed noticeable changes in his face and presence of body hair, which made them to bring the child to medical attention. A review of 254 children on the International Pediatric Adrenocortical Tumour Registry identified virilization as the most common manifestation [10]. About 10% of the tumours can be non-functional at presentation, and approximately one third of pediatric patients present with hypertension. Majority of patients (192/254) in the Registry had localized disease and metastatic disease was found in less than 5% of cases. Older children with CS or mixed androgen and cortisol secreting adrenocortical tumours had a worse prognosis compared to younger children [10]. The present case had mild hypertension as well as dyselectrolytemia at presentation, which could be controlled with medication. He had a single adenoma confined to the adrenal gland and there was no evidence of malignancy. After surgical excision of the tumour and the right adrenal gland, the patient made rapid improvement in clinical condition and has been on follow up for last 7 months.

4. Conclusion

Pediatric adrenocortical tumours (ACTs) are most commonly encountered in females and in children less than four years. But our case being an 4-year-old boy forms a rare presentation of endogenous Cushing’s syndrome due to adrenal adenoma. Cushing’s syndrome in this child was controlled after right adrenalectomy.

Patient consent

Informed written consent was taken.

Funding

No funding or grant support.

Authorship

All authors attest that they meet the current ICMJE criteria for authorship.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

References

Acute and life-threatening complications in Cushing syndrome: Prevalence, predictors and mortality

Researchers conducted this retrospective cohort study to investigate acute and life-threatening complications in patients with active Cushing syndrome (CS). Participants in the study were 242 patients with CS, including 213 with benign CS (pituitary n = 101, adrenal n = 99, ectopic n = 13), and 29 with malignant disease.

In patients with benign pituitary CS, the prevalence of acute complications was 62%, 40% in patients with benign adrenal CS, and 100% in patients with ectopic CS. Infections, thromboembolic events, hypokalemia, hypertensive crises, cardiac arrhythmias and acute coronary events were complications reported in patients with benign CS.

The whole spectrum of acute and life-threatening complications in CS and their high prevalence was illustrated in this study both before disease diagnosis and after successful surgery.

Read the full article on Journal of Clinical Endocrinology and Metabolism.

Thyroid cancer: Cushing syndrome is a lesser-known warning sign – what is it?

Thyroid cancer survival rates are 84 percent for 10 years or more if diagnosed early. Early diagnosis is crucial therefore and spotting the unusual signs could be a matter of life and death. A sign your thyroid cancer has advanced includes Cushing syndrome.

What is it?

What is Cushing syndrome?

 

Cushing syndrome occurs when your body is exposed to high levels of the hormone cortisol for a long time, said the Mayo Clinic.

The health site continued: “Cushing syndrome, sometimes called hypercortisolism, may be caused by the use of oral corticosteroid medication.

“The condition can also occur when your body makes too much cortisol on its own.

“Too much cortisol can produce some of the hallmark signs of Cushing syndrome — a fatty hump between your shoulders, a rounded face, and pink or purple stretch marks on your skin.”

In a study published in the US National Library of Medicine National Institutes of Health, thyroid carcinoma and Cushing’s syndrome was further investigated.

The study noted: “Two cases of thyroid carcinoma and Cushing’s syndrome are reported.

“Both of our own cases were medullary carcinomas of the thyroid, and on reviewing the histology of five of the other cases all proved to be medullary carcinoma with identifiable amyloid in the stroma.

“A consideration of the temporal relationships of the development of the carcinoma and of Cushing’s syndrome suggested that in the two cases with papillary carcinoma these conditions could have been unrelated, but that in eight of the nine cases with medullary carcinoma there was evidence that thyroid carcinoma was present at the time of diagnosis of Cushing’s syndrome.

“Medullary carcinoma of the thyroid is also probably related to this group of tumours. It is suggested that the great majority of the tumours associated with Cushing’s syndrome are derived from cells of foregut origin which are endocrine in nature.”

In rare cases, adrenal tumours can cause Cushing syndrome a condition arising when a tumour secretes hormones the thyroid wouldn’t normally create.

Cushing syndrome associated with medullary thyroid cancer is uncommon.

The syndrome is more commonly caused by the pituitary gland overproducing adrenocorticotropic hormone (ACTH), or by taking oral corticosteroid medication.

See a GP if you have symptoms of thyroid cancer, warns the NHS.

The national health body added: “The symptoms may be caused by less serious conditions, such as an enlarged thyroid, so it’s important to get them checked.

“A GP will examine your neck and can organise a blood test to check how well your thyroid is working.

“If they think you could have cancer or they’re not sure what’s causing your symptoms, you’ll be referred to a hospital specialist for more tests.”

 

Adapted from https://www.express.co.uk/life-style/health/1351753/thyroid-cancer-signs-symptoms-cushing-syndrome