Copeptin Rules Out Diabetes Insipidus Post Pituitary Surgery

The study covered in this summary was published on Research Square as a preprint and has not yet been peer reviewed.

Key Takeaways

  • A study of 78 patients who underwent elective transsphenoidal adenomectomy to remove a pituitary tumor or other lesions within the pituitary fossa at a single center in the UK suggests that postoperative plasma levels of copeptin — a surrogate marker for levels of arginine vasopressin (antidiuretic hormone) — can rule out development of central (neurogenic) diabetes insipidus caused by a deficiency of arginine vasopressin following pituitary surgery.
  • The researchers suggest using as a cutoff a copeptin level of >3.4 pmol/L at postoperative day 1 to rule out diabetes insipidus. Such a cutoff yields the following:
    • A high sensitivity of 91% for ruling out diabetes insipidus.
    • A negative predictive value of 97%. Only 1 of 38 patients with a copeptin value >3.4 pmol/L at day 1 postoperatively developed diabetes insipidus.
    • A low specificity of 55%, meaning that copeptin level is not useful for diagnosing diabetes insipidus

Why This Matters

  • An estimated 1% to 67% of patients who undergo pituitary gland surgery develop diabetes insipidus, often soon after surgery, although it is often transient.
  • Diagnosing diabetes insipidus in such patients requires a combination of clinical assessment, the monitoring of fluid balance, and determining plasma and urine sodium and osmolality.
  • Currently, clinical laboratories in the UK do not have assays for arginine vasopressin, which has a short half-life in vivo and is unstable ex vivo, even when frozen, and is affected by delayed or incomplete separation from platelets.
  • Copeptin, an arginine vasopressin precursor, is much more stable and measurable by commercial immunoassays.
  • The findings suggest that patients who have just undergone pituitary gland surgery and are otherwise healthy and meet the copeptin cutoff for ruling out diabetes insipidus could be discharged 24 hours after surgery and that there is no need for additional clinical and biochemical monitoring. This change would ease demands on the healthcare system.

Study Design

  • The study reviewed 78 patients who underwent elective transsphenoidal adenomectomy to remove a pituitary tumor from November 2017 to June 2020 at the John Radcliffe Hospital in Oxford, United Kingdom.
  • Patients remained in hospital for a minimum of 48 hours after their surgery.
  • Clinicians collected blood and urine specimens preoperatively and at day 1, day 2, day 8, and week 6 post surgery.
  • The patients were restricted to 2 L of fluid a day postoperatively to prevent masking of biochemical abnormalities through compensatory drinking.
  • Diabetes insipidus was suspected when patients’ urine output was >200 mL/h for 3 consecutive hours or >3 L/d plus high plasma sodium (>145 mmol/L) and plasma osmolality (> 295 mosmol/kg) plus inappropriately low urine osmolality. Definitive diagnosis of diabetes insipidus was based on clinical assessment, urine and plasma biochemistry, and need for treatment with desmopressin (1-deamino-8-D-arginine vasopressin).

Key Results

  • The median age of the patients was 55, and 53% were men; 92% of the lesions were macroadenomas; the most common histologic type was gonadotroph tumor (47%).
  • Among the 78 patients, 11 (14%) were diagnosed with diabetes insipidus postoperatively and required treatment with desmopressin; of these, seven patients (9%) continued taking desmopressin after 6 weeks (permanent diabetes insipidus), but the other four did not need to take desmopressin for more than a week.
  • Patients who developed diabetes insipidus were younger than other patients (mean age, 46 vs 56), and 8 of the 11 patients who developed diabetes insipidus (73%) were women.
  • Preoperative copeptin levels were similar in the two groups. At day 1, day 8, and 6 weeks postoperatively, copeptin levels were significantly lower in the diabetes insipidus group; there were no significant differences at day 2, largely because of an outlier result.
  • An area under the receiver operating characteristic curve (AUC; C-statistic) analysis showed that on day 1 after surgery, copeptin levels could account for 74.22% of the incident cases of diabetes insipidus (AUC, 0.7422). On postop day 8, the AUC for copeptin was 0.8015, and after 6 weeks, the AUC associated with copeptin was 0.7321.

Limitations

  • Blood samples for copeptin tests from patients who underwent pituitary surgery were collected at specified times and were frozen for later analysis; performing the test in real time might alter patient management.
  • The study may have missed peak copeptin levels by not determining copeptin levels sooner after pituitary gland surgery, inasmuch as other researchers have reported better predictive values for diagnosing diabetes insipidus from samples taken 1 hour after extubation or <12 hours after surgery.

Disclosures

  • The study did not receive commercial funding.
  • The authors report no relevant financial relationships.

This is a summary of a preprint research study, “Post-Operative Copeptin Analysis Predicts Which Patients Do Not Develop Diabetes Insipidus After Pituitary Surgery,” by researchers from John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, in the United Kingdom. Preprints from Research Square are provided to you by Medscape. This study has not yet been peer reviewed. The full text of the study can be found on researchsquare.com.

Read the article here: https://www.medscape.com/viewarticle/970357#vp_1

Consecutive Adrenal Cushing’s Syndrome and Cushing’s Disease in a Patient With Somatic CTNNB1, USP8, and NR3C1 Mutations

The occurrence of different subtypes of endogenous Cushing’s syndrome (CS) in single individuals is extremely rare. We here present the case of a female patient who was successfully cured from adrenal CS 4 years before being diagnosed with Cushing’s disease (CD).
The patient was diagnosed at the age of 50 with ACTH-independent CS and a left-sided adrenal adenoma, in January 2015. After adrenalectomy and histopathological confirmation of a cortisol-producing adrenocortical adenoma, biochemical hypercortisolism and clinical symptoms significantly improved.
However, starting from 2018, the patient again developed signs and symptoms of recurrent CS. Subsequent biochemical and radiological workup suggested the presence of ACTH-dependent CS along with a pituitary microadenoma. The patient underwent successful transsphenoidal adenomectomy, and both postoperative adrenal insufficiency and histopathological workup confirmed the diagnosis of CD. Exome sequencing excluded a causative germline mutation but showed somatic mutations of the β-catenin protein gene (CTNNB1) in the adrenal adenoma, and of both the ubiquitin specific peptidase 8 (USP8) and the glucocorticoid receptor (NR3C1) genes in the pituitary adenoma. In conclusion, our case illustrates that both ACTH-independent and ACTH-dependent CS may develop in a single individual even without evidence for a common genetic background.

Introduction

Endogenous Cushing´s syndrome (CS) is a rare disorder with an incidence of 0.2–5.0 per million people per year (12). The predominant subtype (accounting for about 80%) is adrenocorticotropic hormone (ACTH)-dependent CS. The vast majority of this subtype is due to an ACTH-secreting pituitary adenoma [so called Cushing´s disease (CD)], whereas ectopic ACTH-secretion (e.g. through pulmonary carcinoids) is much less common. In contrast, ACTH-independent CS can mainly be attributed to cortisol-producing adrenal adenomas. Adrenocortical carcinomas, uni-/bilateral adrenal hyperplasia, and primary pigmented nodular adrenocortical disease (PPNAD) may account for some of these cases as well (34).

Coexistence of different subtypes of endogenous CS in single individuals is even rarer but has been described in few reports. These cases were usually observed in the context of prolonged ACTH stimulation on the adrenal glands, resulting in micronodular or macronodular hyperplasia (59). A sequence of CD and PPNAD was also described in presence of Carney complex, a genetic syndrome characterized by the loss of function of the gene encoding for the regulatory subunit type 1α of protein kinase A (PRKAR1A) (10). Moreover, another group reported the case of a patient with Cushing’s disease followed by ectopic Cushing’s syndrome more than 30 years later (8). To our knowledge, however, we here describe the first case report on a single patient with a cortisol-producing adrenocortical adenoma and subsequent CD.

Read the rest of the article at https://www.frontiersin.org/articles/10.3389/fendo.2021.731579/full

Paediatric patients with Cushing disease and negative pituitary MRI have a higher risk of nonremission after transsphenoidal surgery

Abstract

Objective

Diagnostic workup of Cushing disease (CD) involves imaging evaluation of the pituitary gland, but in many patients no tumour is visualised. The aim of this study is to describe the association of magnetic resonance imaging (MRI) findings with the postoperative course of paediatric and adolescent patients with CD.

Patients

Patients with a diagnosis of CD at less than 21 years of age with MRI evaluation of the pituitary before first transsphenoidal surgery were included.

Measurements

Clinical, imaging and biochemical data were analysed.

Results

One hundred and eighty-six patients with paediatric or adolescent-onset CD were included in the study. Of all patients, 127 (68.3%) had MRI findings consistent with pituitary adenoma, while the remaining had negative or inconclusive MRI. Patients with negative MRI were younger in age and had lower morning cortisol and adrenocorticotropin levels. Of 181 patients with data on postoperative course, patients with negative MRI had higher odds of not achieving remission after the first surgery (odds ratio = 2.6, 95% confidence intervals [CIs] = 1.1–6.0) compared to those with positive MRI. In patients with remission after first transsphenoidal surgery, long-term recurrence risk was not associated with the detection of a pituitary adenoma in the preoperative MRI (hazard risk = 2.1, 95% CI = 0.7–5.8).

Conclusions

Up to one-third of paediatric and adolescent patients with CD do not have a pituitary tumour visualised in MRI. A negative MRI is associated with higher odds of nonremission after surgery; however, if remission is achieved, long-term risk for recurrence is not associated with the preoperative MRI findings.

Full text at https://onlinelibrary.wiley.com/doi/full/10.1111/cen.14560

Experts offer Recommendations for Management of Pituitary Tumors

 

An international panel reached consensus for pre- and postoperative endocrine testing to manage adults undergoing transsphenoidal surgery, including measurement of prolactin and insulin-like growth factor I levels for all pituitary tumors.

In adults and children, transsphenoidal surgery represents the cornerstone of management for most large or functioning sellar lesions with the exception of prolactinomas, Maria Fleseriu, MD, FACE, an Endocrine Today Editorial Board Member, professor of medicine and neurological surgery and director of the Pituitary Center at Oregon Health & Science University in Portland, and colleagues wrote in Pituitary. Endocrine evaluation and management are an essential part of perioperative care; however, the details of endocrine assessment and care are not universally agreed on.

“Perioperative management of patients undergoing pituitary surgery is fascinating, as it involves many specialties — endocrinology, neurosurgery and ENT — and patients also get discharged very quickly in some countries, such as the United States,” Fleseriu told Healio. “At the start of the COVID-19 pandemic, the Physician Education Committee of the Pituitary Society, comprised of members from four continents, met to discuss a more streamlined process for workup before and after surgery for patients undergoing pituitary surgery. We have noticed big differences in management, but also some common themes, and decided to have a formal evaluation using a Delphi consensus and a much larger representation, with members from five continents.”

Building consensus

The task force behind the project, co-led by Nicholas A. Tritos, MD, DSc, associate professor of medicine at Harvard Medical School, and Pouneh K. Fazeli, MD, MPH, director of the neuroendocrinology unit and associate professor of medicine at University of Pittsburgh School of Medicine, created 35 questions and invited 55 pituitary endocrinologists to answer the questions in two Delphi rounds. Participants rated their extent of agreement with statements pertaining to perioperative endocrine evaluation and management, using a Likert-type scale.

Strong consensus, defined as at least 80% of panelists rating their agreement as 6 to 7 on a scale from 1 to 7, was achieved for 24 of 35 items. Less strict agreement, defined as ratings of 5 to 7, was reached for 31 of 35 items.

There were several significant findings, Fleseriu said.

Despite uncertainty in previous guidelines, panelists reached consensus to measure serum IGF-I for all patients with pituitary tumors preoperatively to ensure proper diagnosis of growth hormone excess, Fleseriu said.

“This is important because patients with GH-secreting adenomas do not always present with classic manifestations of acromegaly, require additional evaluation for comorbidities and postoperatively may benefit from further medical therapy or other adjuvant treatment,” Fleseriu said.

Panelists also expressed agreement on preoperative administration of glucocorticoid and thyroid hormone replacement for patients with diagnosed deficiencies, as well as perioperative use of stress-dose glucocorticoid coverage for patients with known or suspected hypoadrenalism, but not for all patients undergoing transsphenoidal surgery. Panelists also agreed on postoperative monitoring of serum sodium and cortisol and the use of desmopressin on-demand, required to control hypernatremia and/or polyuria, for patients with central diabetes insipidus.

“Agreement was achieved on postoperative monitoring of endocrine function, including morning serum cortisol in patients with Cushing’s disease, as well as serum IGF-I in patients with acromegaly,” Fleseriu said.

More research needed

Panelists did not reach consensus for a minority of items, representing areas where further research is needed, including measuring serum prolactin in dilution for all patients with large macroadenomas, Fleseriu said.

“Prolactin immunoassays can be susceptible to the ‘hook effect’ artifact, which may lead to substantial underreporting of prolactin values in sera containing very high prolactin concentrations, thus having important implications for patient management,” Fleseriu said. “Newer automated immunoassay platforms are likely to detect the hook effect; however, this may not be the case in older assays, which are still in use in many countries or laboratories. Therefore, especially when surgery is performed at an institution where automated assays are available to detect hook effect, yet patient workup has been carried out at an outside laboratory, additional lab workup might be needed. We envision this scenario can occur more often with the widespread use of telemedicine and endocrine testing being carried out at a distant laboratory.”

Additionally, there was a lack of consensus regarding preoperative testing for hypercortisolism in all patients with an apparently nonfunctioning pituitary adenoma. “This might reflect concern about false-positive results of endocrine testing in some individuals,” Fleseriu said. “On the other hand, published data suggest that some patients with Cushing’s disease may lack typical symptoms and signs and can present with an incidentally found sellar mass.”

Panelists did not reach consensus on items concerning preoperative medical therapy for patients with acromegaly or Cushing’s disease, potentially reflecting differences in practice among international centers, the clinical heterogeneity of patient populations, and ongoing uncertainties regarding the benefits of preoperative medical therapy.

“Single-center clinical experience suggests that preoperative medical therapy may be helpful in patients with Cushing’s disease and severe acute psychiatric illness or sepsis,” Fleseriu said. “Studies on acromegaly have very discordant results.

“With this study — the largest international Delphi consensus on perioperative management of patients undergoing pituitary surgery — we identified key steps in protocols which are ready to be implemented in most centers, especially for preoperative evaluation, sodium abnormalities and glucocorticoids administration postop,” Fleseriu said. “We have also highlighted several areas where need for more research is needed to optimize patients’ outcomes.”

For more information:

Maria Fleseriu, MD, FACE, can be reached at fleseriu@ohsu.edu; Twitter: @MariaFleseriu.

From https://www.healio.com/news/endocrinology/20210810/experts-offer-recommendations-for-management-of-pituitary-tumors

Predicting Prolonged Length of Stay After Endoscopic Transsphenoidal Surgery for Pituitary Adenoma

First published:03 May 2020
Read the entire article at https://doi.org/10.1002/alr.22540

Potential conflict of interest: None disclosed.

Presented at the 65th Annual Meeting of the American Rhinologic Society, on September 14, 2019, in New Orleans, LA.

Abstract

Background

Endoscopic transsphenoidal surgery (ETS) for the resection of pituitary adenoma has become more common throughout the past decade. Although most patients have a short postoperative hospitalization, others require a more prolonged stay. We aimed to identify predictors for prolonged hospitalization in the setting of ETS for pituitary adenomas.

Methods

A retrospective chart review as performed on 658 patients undergoing ETS for pituitary adenoma at a single tertiary care academic center from 2005 to 2019. Length of stay (LoS) was defined as date of surgery to date of discharge. Patients with LoS in the top 10th percentile (prolonged LoS [PLS] >4 days, N = 72) were compared with the remainder (standard LoS [SLS], N = 586).

Results

The average age was 54 years and 52.5% were male. The mean LoS was 2.1 days vs 7.5 days (SLS vs PLS). On univariate analysis, atrial fibrillation (p = 0.002), hypertension (p = 0.033), partial tumor resection (p < 0.001), apoplexy (p = 0.020), intraoperative cerebrospinal fluid (ioCSF) leak (p = 0.001), nasoseptal flap (p = 0.049), postoperative diabetes insipidus (DI) (p = 0.010), and readmission within 30 days (p = 0.025) were significantly associated with PLS. Preoperative continuous positive airway pressure (CPAP) (odds ratio, 15.144; 95% confidence interval, 2.596‐88.346; p = 0.003) and presence of an ioCSF leak (OR, 10.362; 95% CI, 2.143‐50.104; p = 0.004) remained significant on multivariable analysis.

Conclusion

For patients undergoing ETS for pituitary adenomas, an ioCSF leak or preoperative use of CPAP predicted PLS. Additional common reasons for PLS included postoperative CSF leak (10 of 72), management of DI or hypopituitarism (15 of 72), or reoperation due to surgical or medical complications (14 of 72).

From https://onlinelibrary.wiley.com/doi/abs/10.1002/alr.22540?af=R