Browse

You are looking at 1 - 5 of 5 items

Open access

Lima Lawrence, Peng Zhang, Humberto Choi, Usman Ahmad, Valeria Arrossi, Andrei Purysko and Vinni Makin

Summary

Ectopic adrenocorticotropic hormone (ACTH) production leading to ectopic ACTH syndrome accounts for a small proportion of all Cushing’s syndrome (CS) cases. Thymic neuroendocrine tumors are rare neoplasms that may secrete ACTH leading to rapid development of hypercortisolism causing electrolyte and metabolic abnormalities, uncontrolled hypertension and an increased risk for opportunistic infections. We present a unique case of a patient who presented with a mediastinal mass, revealed to be an ACTH-secreting thymic neuroendocrine tumor (NET) causing ectopic CS. As the diagnosis of CS from ectopic ACTH syndrome (EAS) remains challenging, we emphasize the necessity for high clinical suspicion in the appropriate setting, concordance between biochemical, imaging and pathology findings, along with continued vigilant monitoring for recurrence after definitive treatment.

Learning points:

  • Functional thymic neuroendocrine tumors are exceedingly rare.

  • Ectopic Cushing’s syndrome secondary to thymic neuroendocrine tumors secreting ACTH present with features of hypercortisolism including electrolyte and metabolic abnormalities, uncontrolled hypertension and hyperglycemia, and opportunistic infections.

  • The ability to undergo surgery and completeness of resection are the strongest prognostic factors for improved overall survival; however, the recurrence rate remains high.

  • A high degree of initial clinical suspicion followed by vigilant monitoring is required for patients with this challenging disease.

Open access

Matthieu St-Jean, Jessica MacKenzie-Feder, Isabelle Bourdeau and André Lacroix

Summary

A 29-year-old G4A3 woman presented at 25 weeks of pregnancy with progressive signs of Cushing’s syndrome (CS), gestational diabetes requiring insulin and hypertension. A 3.4 × 3.3 cm right adrenal adenoma was identified during abdominal ultrasound imaging for nephrolithiasis. Investigation revealed elevated levels of plasma cortisol, 24 h urinary free cortisol (UFC) and late-night salivary cortisol (LNSC). Serum ACTH levels were not fully suppressed (4 and 5 pmol/L (N: 2–11)). One month post-partum, CS regressed, 24-h UFC had normalised while ACTH levels were now less than 2 pmol/L; however, dexamethasone failed to suppress cortisol levels. Tests performed in vivo 6 weeks post-partum to identify aberrant hormone receptors showed no cortisol stimulation by various tests (including 300 IU hLH i.v.) except after administration of 250 µg i.v. Cosyntropin 1–24. Right adrenalectomy demonstrated an adrenocortical adenoma and atrophy of adjacent cortex. Quantitative RT-PCR analysis of the adenoma revealed the presence of ACTH (MC2) receptor mRNA, while LHCG receptor mRNA was almost undetectable. This case reveals that CS exacerbation in the context of pregnancy can result from the placental-derived ACTH stimulation of MC2 receptors on the adrenocortical adenoma. Possible contribution of other placental-derived factors such as oestrogens, CRH or CRH-like peptides cannot be ruled out.

Learning points:

  • Diagnosis of Cushing’s syndrome during pregnancy is complicated by several physiological alterations in hypothalamic–pituitary–adrenal axis regulation occurring in normal pregnancy.

  • Cushing’s syndrome (CS) exacerbation during pregnancy can be associated with aberrant expression of LHCG receptor on primary adrenocortical tumour or hyperplasia in some cases, but not in this patient.

  • Placental-derived ACTH, which is not subject to glucocorticoid negative feedback, stimulated cortisol secretion from this adrenal adenoma causing transient CS exacerbation during pregnancy.

  • Following delivery and tumour removal, suppression of HPA axis can require several months to recover and requires glucocorticoid replacement therapy.

Open access

S F Wan Muhammad Hatta, L Kandaswamy, C Gherman-Ciolac, J Mann and H N Buch

Summary

Myopathy is a well-known complication of hypercortisolism and commonly involves proximal lower-limb girdle. We report a rare case of Cushing’s syndrome in a 60-year-old female presenting with significant respiratory muscle weakness and respiratory failure. She had history of rheumatoid arthritis, primary biliary cirrhosis and primary hypothyroidism and presented with weight gain and increasing shortness of breath. Investigations confirmed a restrictive defect with impaired gas transfer but with no significant parenchymatous pulmonary disease. Respiratory muscle test confirmed weakness of respiratory muscles and diaphragm. Biochemical and radiological investigations confirmed hypercortisolaemia secondary to a left adrenal tumour. Following adrenalectomy her respiratory symptoms improved along with an objective improvement in the respiratory muscle strength, diaphragmatic movement and pulmonary function test.

Learning points:

  • Cushing’s syndrome can present in many ways, a high index of suspicion is required for its diagnosis, as often patients present with only few of the pathognomonic symptoms and signs of the syndrome.

  • Proximal lower-limb girdle myopathy is common in Cushing’s syndrome. Less often long-term exposure of excess glucocorticoid production can also affect other muscles including respiratory muscle and the diaphragm leading to progressive shortness of breath and even acute respiratory failure.

  • Treatment of Cushing’s myopathy involves treating the underlying cause that is hypercortisolism. Various medications have been suggested to hinder the development of GC-induced myopathy, but their effects are poorly analysed.

Open access

Maria Mercedes Pineyro, Daiana Arrestia, Mariana Elhordoy, Ramiro Lima, Saul Wajskopf, Raul Pisabarro and Maria Pilar Serra

Summary

Spontaneous reossification of the sellar floor after transsphenoidal surgery has been rarely reported. Strontium ranelate, a divalent strontium salt, has been shown to increase bone formation, increasing osteoblast activity. We describe an unusual case of a young patient with Cushing’s disease who was treated with strontium ranelate for low bone mass who experienced spontaneous sellar reossification after transsphenoidal surgery. A 21-year-old male presented with Cushing’s features. His past medical history included delayed puberty diagnosed at 16 years, treated with testosterone for 3 years without further work-up. He was diagnosed with Cushing’s disease initially treated with transsphenoidal surgery, which was not curative. The patient did not come to follow-up visits for more than 1 year. He was prescribed strontium ranelate 2 g orally once daily for low bone mass by an outside endocrinologist, which he received for more than 1 year. Two years after first surgery he was reevaluated and persisted with active Cushing’s disease. Magnetic resonance image revealed a left 4 mm hypointense mass, with sphenoid sinus occupation by a hyperintense material. At repeated transsphenoidal surgery, sellar bone had a very hard consistency; surgery was complicated and the patient died. Sellar reossification negatively impacted surgery outcomes in this patient. While this entity is possible after transsphenoidal surgery, it remains unclear whether strontium ranelate could have affected sellar ossification.

Learning points:

  • Delayed puberty can be a manifestation of Cushing’s syndrome. A complete history, physical examination and appropriate work-up should be performed before initiating any treatment.

  • Sellar reossification should always be taken into account when considering repeated transsphenoidal surgery. Detailed preoperative evaluation of bony structures by computed tomography ought to be performed in all cases of reoperation.

  • We speculate if strontium ranelate may have affected bone mineralization at the sellar floor. We strongly recommend that indications for prescribing this drug should be carefully followed.

Open access

Kharis Burns, Darshika Christie-David and Jenny E Gunton

Summary

Ketoconazole was a first-line agent for suppressing steroidogenesis in Cushing's disease. It now has limited availability. Fluconazole, another azole antifungal, is an alternative, although its in vivo efficacy is unclear. A 61-year-old female presented with weight gain, abdominal striae and worsening depression. HbA1c increased to 76 mmol/mol despite increasing insulin. Investigations confirmed cortisol excess; afternoon serum cortisol was 552 nmol/l with an inappropriate ACTH of 9.3 pmol/l. In total, 24-h urinary free cortisol (UFC):creatinine ratio was 150 nmol/mmol with failure to suppress after 48 h of low-dose dexamethasone. Pituitary MRI revealed a 4-mm microadenoma. Inferior petrosal sinus sampling confirmed Cushing's disease. Transsphenoidal resection was performed and symptoms improved. However, disease recurred 6 months later with elevated 24-h UFC >2200 nmol/day. Metyrapone was commenced at 750 mg tds. Ketoconazole was later added at 400 mg daily, with dose reduction in metyrapone. When ketoconazole became unavailable, fluconazole 200 mg daily was substituted. Urine cortisol:creatinine ratio rose, and the dose was increased to 400 mg daily with normalisation of urine hormone levels. Serum cortisol and urine cortisol:creatinine ratios remain normal on this regimen at 6 months. In conclusion, to our knowledge, this is the first case demonstrating prolonged in vivo efficacy of fluconazole in combination with low-dose metyrapone for the treatment of Cushing's disease. Fluconazole has a more favourable toxicity profile, and we suggest that it is a potential alternative for medical management of Cushing's disease.

Learning points

  • Surgery remains first line for the management of Cushing's disease with pharmacotherapy used where surgery is unsuccessful or there is persistence of cortisol excess.

  • Ketoconazole has previously been used to treat cortisol excess through inhibition of CYP450 enzymes 11-β-hydroxylase and 17-α-hydroxylase, though its availability is limited in many countries.

  • Fluconazole shares similar properties to ketoconazole, although it has less associated toxicity.

  • Fluconazole represents a suitable alternative for the medical management of Cushing's disease and proved an effective addition to metyrapone in the management of this case.