Evaluation of Hypothalamic-Pituitary-Adrenal Axis by the GHRP2 Test: Comparison With the Insulin Tolerance Test

Slowly Progressive Secondary Adrenal Insufficiency Due to Pembrolizumab Administration in a Patient With a History of Pituitary Neuroendocrine Tumor

A 70-year-old man developed anorexia, general malaise, and hyponatremia with a serum sodium level of 120 mEq/L after the fifth cycle of pembrolizumab administration for bladder cancer. A rapid adrenocorticotropic hormone (ACTH) loading test result was within the normal range (basal and peak cortisol levels of 8.2 μg/dL and 20.0 μg/dL, respectively), and his serum sodium level recovered by salt loading. However, about two weeks later, his anorexia and malaise worsened, and his serum sodium level decreased to 122 mEq/L. A rapid ACTH loading test performed again four weeks after the first test showed a peak cortisol level of 13.4 μg/dL, and a corticotropin-releasing hormone (CRH) loading test showed basal ACTH and cortisol levels of 19 pg/mL and 6.3 μg/dL and peak levels of 34 pg/mL and 8.7 μg/dL, respectively. Therefore, secondary adrenal insufficiency (SAI) was diagnosed. Although he underwent nonfunctioning pituitary neuroendocrine tumor resection at the age of 55 years, the tumor was not significantly different from the postoperative findings. The possible cause of SAI was ACTH deficiency after pembrolizumab administration. Four months after diagnosis, the basal ACTH and cortisol levels had decreased from 19 to 17 pg/mL and from 6.0 to 3.2 μg/dL, respectively. We were able to follow the atypical, slowly progressive course of SAI due to pembrolizumab.

A Japanese Boy with Dysmorphic Syndrome with Multiple Pituitary Hormone Deficiency and Gingival Fibromatosis Due to a Pathogenic KCNQ1 Variant

A six-year-old boy presented with short stature and gingival fibromatosis (GF). Dysmorphic features included slant optic fissures, a high-arched palate, thick earlobes, and an edematous face. Laboratory tests showed low levels of serum insulin-like growth factor-1 and serum free thyroxine but normal serum thyrotropin levels. Provocative tests suggested growth hormone deficiency, central hypocortisolemia, and hypothalamic hypothyroidism. At 12 years old, hypogonadotropic hypogonadism was observed. Next-generation sequencing revealed a heterozygous missense variant, KCNQ1 p. (P369L), in the proband and mother. The coexistence of multiple pituitary hormone deficiencies and GF helps diagnose KCNQ1-variant dysmorphic syndrome through genetic testing.

Isolated Adrenocorticotropic Hormone Deficiency Associated with Atezolizumab and Bevacizumab Administration for Treating Hepatocellular Carcinoma: A Case Series

Atezolizumab and bevacizumab are currently available as first-line treatments for unresectable hepatocellular carcinoma, but immune-related adverse events are a major concern. We herein report two cases of isolated adrenocorticotropic hormone (ACTH) deficiency. Both patients presented with general fatigue, appetite loss, eosinophilia, and hyponatremia after nine cycles in case 1 and three months after stopping treatment for inflammatory arthritis in case 2. Endocrinological investigations revealed unsatisfactory ACTH and cortisol responses despite the preservation of other anterior pituitary hormones, suggesting isolated ACTH deficiency. As it is rapidly improved by steroid replacement therapy, an early diagnosis and treatment make it possible to resume immunotherapy.

Assessment of anterior pituitary reserve capacity based on growth hormone response to growth hormone-releasing peptide-2 test in the elderly

OBJECTIVE

The growth hormone (GH)-releasing peptide-2 (GHRP-2) test is relatively safe among endocrine stimulation tests for the elderly. We investigated whether anterior pituitary function in elderly patients could be assessed on the basis of GH response to the GHRP-2 test.

DESIGN

Sixty-five elderly patients aged 65 years and older with non-functioning pituitary neuroendocrine tumor (PitNET) who underwent pituitary surgery and preoperative endocrine stimulation tests were classified into the "GH normal group" and "GH deficiency group" based on GH response to the GHRP-2 test. The baseline characteristics and anterior pituitary function were compared between the groups.

RESULTS

Thirty-two patients were assigned to the GH normal group and 33 to the GH deficiency group. The cortisol and adrenocorticotropic hormone (ACTH) results in the corticotropin-releasing hormone test were significantly higher in the GH normal group than in the GH deficiency group (p < 0.001). The relationship between the cortisol and ACTH results and the GH response revealed significant correlations (p < 0.001). In addition, receiver operating characteristic curve analysis identified that the optimal cut-off point for a peak GH level in the correlation between adrenocortical function and GH response to the GHRP-2 test was 8.08 ng/mL (specificity 0.868, sensitivity 0.852).

CONCLUSION

The present study indicated that adrenocortical function was significantly correlated with GH response to the GHRP-2 test in elderly patients before pituitary surgery. For elderly patients with non-functioning PitNET, GH response to the GHRP-2 test may support in diagnosing adrenocortical insufficiency.

Clinical usefulness of the growth hormone-releasing peptide-2 test for hypothalamic-pituitary disorder

Purpose

Growth hormone deficiency (GHD) develops early in patients with hypothalamic-pituitary disorder and is frequently accompanied by other anterior pituitary hormone deficiencies including secondary adrenal insufficiency (AI). A growth hormone-releasing peptide-2 (GHRP2), which is wildly used for the diagnosis of patients with GHD, has been considered to induce not only growth hormone (GH) release but also ACTH release. However, its clinical usefulness in hypothalamic-pituitary disorder is unclear.

Methods

The GHRP2 test, a cosyntropin stimulation test, corticotropin-releasing hormone (CRH) tests and/or insulin tolerance tests (ITTs) were performed on 36 patients having hypothalamic-pituitary disorder.

Results

Twenty-two (61%) had severe GHD, and 3 (8%) had moderate GHD by GHRP2. There was no difference in baseline ACTH and cortisol between non-GHD, moderate GHD and severe GHD participants. However, a cosyntropin stimulation test and subsequent CRH tests and/or ITTs revealed that 17 (47%) had secondary AI and 16/17 (94%) cases of secondary AI were concomitant with severe GHD. ROC curve analysis demonstrated that the ACTH response in the GHRP2 test was useful for screening pituitary-AI, with a cut-off value of 1.55-fold (83% sensitivity and 88% specificity). Notably, the combination of ACTH response and the peak cortisol level in the GHRP2 test using each cut-off value (1.55-fold and 10 µg/dl, respectively) showed high specificity (100%) with high accuracy (0.94) for diagnosis of pituitary-AI.

Conclusion

We recommend measuring ACTH as well as GH during the GHRP2 test to avoid overlooking and delays in diagnosis of secondary AI that frequently accompanies GHD.

Opioid-induced adrenal insufficiency in transdermal fentanyl treatment: a revisited diagnosis in clinical setting

Opioids are widely used for treatment of acute and chronic pain. However, opioids have several well-known clinical adverse effects such as constipation, nausea, respiratory depression and drowsiness. Endocrine dysfunctions are also opioid-induced adverse effects but remain under-diagnosed in clinical settings, especially opioid-induced adrenal insufficiency (OIAI). A 46-year-old woman was treated with transdermal fentanyl at a dose of 90-120 mg daily morphine milligram equivalent for non-malignant chronic pain for four years. Fatigue, loss of appetite and decrease in vitality began about two years after starting fentanyl. Subsequently, constipation and abdominal pain appeared and became worse, which led to suspicion of adrenal insufficiency. Clinical diagnosis of OIAI was established based on laboratory findings of secondary adrenal insufficiency, including corticotropin-releasing hormone stimulation test, clinical history of long-term fentanyl use, and exclusion of other hypothalamic-pituitary diseases. Oral corticosteroid replacement therapy was unable to relieve her abdominal pain and constipation; opioid-rotation and dose-reduction of fentanyl were not feasible because of her persistent pain and severe anxiety. While her clinical course clearly suggested that long-term, relatively high-dose transdermal fentanyl treatment may have contributed to the development of secondary adrenal insufficiency, the symptoms associated with OIAI are generally non-specific and complex. Together with under-recognition of OIAI as a clinical entity, the non-specific, wide range of symptoms can impede prompt diagnosis. Thus, vigilance for early symptoms enabling treatments including corticosteroid replacement therapy is necessary for patients taking long-term and/or high dose opioid treatment.

Secondary Adrenal Insufficiency: Recent Updates and New Directions for Diagnosis and Management

Secondary adrenal insufficiency is the most common subtype of adrenal insufficiency; it is caused by certain medications and pituitary destruction (pituitary masses, inflammation, or infiltration) and is rarely associated with certain germline variants. In this review, we discuss the etiology, epidemiology, and clinical presentation of secondary adrenal insufficiency and focus on the diagnostic and management challenges. We also review the management of selected special populations of patients and discuss patient-important outcomes associated with secondary adrenal insufficiency.

Provocative growth hormone testing in children: how did we get here and where do we go now?

OBJECTIVES

Provocative growth hormone (GH) tests are widely used for diagnosing pediatric GH deficiency (GHD). A thorough understanding of the evidence behind commonly used interpretations and the limitations of these tests is important for improving clinical practice.

CONTENT

To place current practice into a historical context, the supporting evidence behind the use of provocative GH tests is presented. By reviewing GH measurement techniques and examining the early data supporting the most common tests and later studies that compared provocative agents to establish reference ranges, the low sensitivity and specificity of these tests become readily apparent. Studies that assess the effects of patient factors, such as obesity and sex steroids, on GH testing further bring the appropriateness of commonly used cutoffs for diagnosing GHD into question.

SUMMARY AND OUTLOOK

Despite the widely recognized poor performance of provocative GH tests in distinguishing GH sufficiency from deficiency, limited progress has been made in improving them. New diagnostic modalities are needed, but until they become available, clinicians can improve the clinical application of provocative GH tests by taking into account the multiple factors that influence their results.

Investigation of the Hypothalamo-pituitary-adrenal (HPA) axis: a contemporary synthesis

The hypothalamo-pituitary-adrenal (HPA) axis is one of the main components of the stress system. Maintenance of normal physiological events, which include stress responses to internal or external stimuli in the body, depends on appropriate HPA axis function. In the case of severe cortisol deficiency, especially when there is a triggering factor, the patient may develop a life-threatening adrenal crisis which may result in death unless early diagnosis and adequate treatment are carried out. The maintenance of normal physiology and survival depend upon a sufficient level of cortisol in the circulation. Life-long glucocorticoid replacement therapy, in most cases meeting but not exceeding the need of the patient, is essential for normal life expectancy and maintenance of the quality of life. To enable this, the initial step should be the correct diagnosis of adrenal insufficiency (AI) which requires careful evaluation of the HPA axis, a highly dynamic endocrine system. The diagnosis of AI in patients with frank manifestations is not challenging. These patients do not need dynamic tests, and basal cortisol is usually enough to give a correct diagnosis. However, most cases of secondary adrenal insufficiency (SAI) take place in a gray zone when clinical manifestations are mild. In this situation, more complicated methods that can simulate the response of the HPA axis to a major stress are required. Numerous studies in the assessment of HPA axis have been published in the world literature. In this review, the tests used in the diagnosis of secondary AI or in the investigation of suspected HPA axis insufficiency are discussed in detail, and in the light of this, various recommendations are made.

Diagnosis, Genetics, and Therapy of Short Stature in Children: A Growth Hormone Research Society International Perspective

The Growth Hormone Research Society (GRS) convened a Workshop in March 2019 to evaluate the diagnosis and therapy of short stature in children. Forty-six international experts participated at the invitation of GRS including clinicians, basic scientists, and representatives from regulatory agencies and the pharmaceutical industry. Following plenary presentations addressing the current diagnosis and therapy of short stature in children, breakout groups discussed questions produced in advance by the planning committee and reconvened to share the group reports. A writing team assembled one document that was subsequently discussed and revised by participants. Participants from regulatory agencies and pharmaceutical companies were not part of the writing process. Short stature is the most common reason for referral to the pediatric endocrinologist. History, physical examination, and auxology remain the most important methods for understanding the reasons for the short stature. While some long-standing topics of controversy continue to generate debate, including in whom, and how, to perform and interpret growth hormone stimulation tests, new research areas are changing the clinical landscape, such as the genetics of short stature, selection of patients for genetic testing, and interpretation of genetic tests in the clinical setting. What dose of growth hormone to start, how to adjust the dose, and how to identify and manage a suboptimal response are still topics to debate. Additional areas that are expected to transform the growth field include the development of long-acting growth hormone preparations and other new therapeutics and diagnostics that may increase adult height or aid in the diagnosis of growth hormone deficiency.