Summary

Severe hyponatremia and osmotic demyelination syndrome (ODS) are opposite ends of a spectrum of emergency disorders related to sodium concentrations. Management of severe hyponatremia is challenging because of the difficulty in balancing the risk of overcorrection leading to ODS as well as under-correction causing cerebral oedema, particularly in a patient with chronic hypocortisolism and hypothyroidism. We report a case of a patient with Noonan syndrome and untreated anterior hypopituitarism who presented with symptomatic hyponatremia and developed transient ODS.

Learning points:

• Patients with severe anterior hypopituitarism with severe hyponatremia are susceptible to the rapid rise of sodium level with a small amount of fluid and hydrocortisone.

• These patients with chronic anterior hypopituitarism are at high risk of developing ODS and therefore, care should be taken to avoid a rise of more than 4–6 mmol/L per day.

• Early recognition and rescue desmopressin and i.v. dextrose 5% fluids to reduce serum sodium concentration may be helpful in treating acute ODS.

Summary

Isolated, adult-onset central hypothyroidism is very rare, and its diagnosis can be challenging. A 42-year-old patient was referred for evaluation of a 2.8 cm thyroid nodule. She referred symptoms that could be attributed to hypothyroidism and thyroid tests showed low TSH and normal-low levels of free T4. However, evaluation of the remaining pituitary hormones and pituitary MRI were normal, yet a radionuclide scanning revealed that the thyroid nodule was ‘hot’ and the tracer uptake in the remaining thyroid tissue was suppressed. Interpretation of these studies led to a misdiagnosis of subclinical hyperthyroidism and the patient was treated with radioiodine. Soon after treatment, she developed a frank hypothyroidism without appropriate elevation of TSH and the diagnosis of central hypothyroidism was made a posteriori. Long term follow-up revealed a progressive pituitary failure, with subsequent deficiency of ACTH and GH. This case should alert to the possibility of overlooking central hypothyroidism in patients simultaneously bearing primary thyroid diseases able to cause subclinical hyperthyroidism.

Learning points:

• Although rarely, acquired central hypothyroidism can occur in the absence of other pituitary hormone deficiencies.

• In these cases, diagnosis is challenging, as symptoms are unspecific and usually mild, and laboratory findings are variable, including low, normal or even slightly elevated TSH levels, along with low or low-normal concentrations of free T4.

• In cases with low TSH levels, the coexistence of otherwise common disorders able to cause primary thyroid hyperfunction, such as autonomous nodular disease, may lead to a misdiagnosis of subclinical hyperthyroidism.

Summary

Cushing’s disease is a rare disorder characterised by excessive cortisol production as a consequence of a corticotroph pituitary tumour. While the primary treatment is surgical resection, post-operative radiation therapy may be used in cases of ongoing inadequate hormonal control or residual or progressive structural disease. Despite improved outcomes, radiotherapy for pituitary tumours is associated with hypopituitarism, visual deficits and, rarely, secondary malignancies. We describe an unusual case of a 67-year-old female with presumed Cushing’s disease diagnosed at the age of 37, treated with transsphenoidal resection of a pituitary tumour with post-operative external beam radiotherapy (EBRT), ketoconazole for steroidogenesis inhibition, and finally bilateral adrenalectomy for refractory disease. She presented 30 years after her treatment with a witnessed generalised tonic-clonic seizure. Radiological investigations confirmed an extracranial mass infiltrating through the temporal bone and into brain parenchyma. Due to recurrent generalised seizures, the patient was intubated and commenced on dexamethasone and anti-epileptic therapy. Resection of the tumour revealed a high-grade osteoblastic osteosarcoma. Unfortunately, the patient deteriorated in intensive care and suffered a fatal cardiac arrest following a likely aspiration event. We describe the risk factors, prevalence and treatment of radiation-induced osteosarcoma, an exceedingly rare and late complication of pituitary irradiation. To our knowledge, this is the longest reported latency period between pituitary irradiation and the development of an osteosarcoma of the skull.

Learning points:

• Cushing’s disease is treated with transsphenoidal resection as first-line therapy, with radiotherapy used in cases of incomplete resection, disease recurrence or persistent hypercortisolism.

• The most common long-term adverse outcome of pituitary tumour irradiation is hypopituitarism occurring in 30–60% of patients at 10 years, and less commonly, vision loss and oculomotor nerve palsies, radiation-induced brain tumours and sarcomas.

• Currently proposed characteristics of radiation-induced osteosarcomas include: the finding of a different histological type to the primary tumour, has developed within or adjacent to the path of the radiation beam, and a latency period of at least 3 years.

• Treatment of osteosarcoma of the skull include complete surgical excision, followed by systemic chemotherapy and/or radiotherapy.

• Overall prognosis in radiation-induced sarcoma of bone is poor.

• Newer techniques such as stereotactic radiosurgery may reduce the incidence of radiation-induced malignancies.

Summary

Primary bilateral macronodular adrenal hyperplasia (PBMAH) is a rare cause of ACTH-independent Cushing syndrome (CS). This condition is characterized by glucocorticoid and/or mineralocorticoid excess, and is commonly regulated by aberrant G-protein coupled receptor expression may be subclinical, allowing the disease to progress for years undetected. Inhibin A is a glycoprotein hormone and tumor marker produced by certain endocrine glands including the adrenal cortex, which has not been previously investigated as a potential tumor marker for PBMAH. In the present report, serum inhibin A levels were evaluated in three patients with PBMAH before and after adrenalectomy. In all cases, serum inhibin A was elevated preoperatively and subsequently fell within the normal range after adrenalectomy. Additionally, adrenal tissues stained positive for inhibin A. We conclude that serum inhibin A levels may be a potential tumor marker for PBMAH.

Learning points:

• PBMAH is a rare cause of CS.

• PBMAH may have an insidious presentation, allowing the disease to progress for years prior to diagnosis.

• Inhibin A is a heterodimeric glycoprotein hormone expressed in the gonads and adrenal cortex.

• Inhibin A serum concentrations are elevated in some patients with PBMAH, suggesting the potential use of this hormone as a tumor marker.

• Further exploration of serum inhibin A concentration, as it relates to PBMAH disease progression, is warranted to determine if this hormone could serve as an early detection marker and/or predictor of successful surgical treatment.

Summary

Multiple endocrine metastases are a rare but possible complication of lung adenocarcinoma (LAC). Pituitary metastasis is a rare condition with poor clinical expression. Diabetes insipidus (DI) is its most common presenting symptom. Here we report an original case of a pituitary stalk (PS) metastasis from LAC presenting as central DI followed by adrenal insufficiency (AI) from bilateral adrenal metastasis, without known evidence of the primary malignancy. A 45-year-old woman whose first clinical manifestations were polyuria and polydipsia was admitted. She was completely asymptomatic with no cough, no weight loss or anorexia. Chest radiography was normal. Brain MRI showed a thick pituitary stalk (PS). DI was confirmed by water restriction test and treated with vasopressin with great clinical results. Explorations for systemic and infectious disease were negative. Few months later, an acute AI led to discovering bilateral adrenal mass on abdominal CT. A suspicious 2.3 cm apical lung nodule was found later. Histopathological adrenal biopsy revealed an LAC. The patient received systemic chemotherapy with hormonal replacement for endocrinological failures by both vasopressin and hydrocortisone. We present this rare case of metastatic PS thickness arising from LAC associated with bilateral adrenal metastasis. Screening of patients with DI and stalk thickness for lung and breast cancer must be considered. Multiple endocrine failures as a diagnostic motive of LAC is a rare but possible circumstance.

Learning points:

• Adrenal metastasis is a common location in lung adenocarcinoma; however, metastatic involvement of the pituitary stalk remains a rare occurrence, especially as a leading presentation to diagnose lung cancer.

• The posterior pituitary and the infundibulum are the preferential sites for metastases, as they receive direct arterial blood supply from hypophyseal arteries.

• Patients diagnosed with diabetes insipidus due to pituitary stalk thickness should be considered as a metastasis, after exclusion of the classical systemic and infectious diseases.

• The diagnosis of an endocrinological metastatic primary lung adenocarcinoma for patients without respiratory symptoms is often delayed due to a lack of correlation between endocrinological symptoms and lung cancer.

• The main originality of our case is the concomitant diagnosis of both endocrinological failures, as it was initiated with a diabetes insipidus and followed by an acute adrenal insufficiency.

Summary

Cushing’s syndrome is an endocrine disorder that causes anovulatory infertility secondary to hypercortisolism; therefore, pregnancy rarely occurs during its course. We present the case of a 24-year-old, 16-week pregnant female with a 10-month history of unintentional weight gain, dorsal gibbus, nonpruritic comedones, hirsutism and hair loss. Initial biochemical, hormonal and ultrasound investigations revealed hypokalemia, increased nocturnal cortisolemia and a right adrenal mass. The patient had persistent high blood pressure, hyperglycemia and hypercortisolemia. She was initially treated with antihypertensive medications and insulin therapy. Endogenous Cushing’s syndrome was confirmed by an abdominal MRI that demonstrated a right adrenal adenoma. The patient underwent right laparoscopic adrenalectomy and anatomopathological examination revealed an adrenal adenoma with areas of oncocytic changes. Finally, antihypertensive medication was progressively reduced and glycemic control and hypokalemia reversal were achieved. Long-term therapy consisted of low-dose daily prednisone. During follow-up, despite favorable outcomes regarding the patient’s Cushing’s syndrome, stillbirth was confirmed at 28 weeks of pregnancy. We discuss the importance of early diagnosis and treatment of Cushing’s syndrome to prevent severe maternal and fetal complications.

Learning points:

• Pregnancy can occur, though rarely, during the course of Cushing’s syndrome.

• Pregnancy is a transient physiological state of hypercortisolism and it must be differentiated from Cushing’s syndrome based on clinical manifestations and laboratory tests.

• The diagnosis of Cushing’s syndrome during pregnancy may be challenging, particularly in the second and third trimesters because of the changes in the maternal hypothalamic-pituitary-adrenal axis.

• Pregnancy during the course of Cushing’s syndrome is associated with severe maternal and fetal complications; therefore, its early diagnosis and treatment is critical.

Summary

Pituitary infections, particularly with fungus, are rare disorders that usually occur in immunocompromised patients. Cushing’s syndrome predisposes patients to infectious diseases due to their immunosuppression status. We report the case of a 55-year-old woman, working as a poultry farmer, who developed intense headache, palpebral ptosis, anisocoria, prostration and psychomotor agitation 9 months after initial diabetes mellitus diagnosis. Cranioencephalic CT scan showed a pituitary lesion with bleeding, suggesting pituitary apoplexy. Patient underwent transsphenoidal surgery and the neuropathologic study indicated a corticotroph adenoma with apoplexy and fungal infection. Patient had no preoperative Cushing’s syndrome diagnosis. She was evaluated by a multidisciplinary team who decided not to administer anti-fungal treatment. The reported case shows a rare association between a corticotroph adenoma and a pituitary fungal infection. The possible contributing factors were hypercortisolism, uncontrolled diabetes and professional activity. Transsphenoidal surgery is advocated in these infections; however, anti-fungal therapy is still controversial.

Learning points:

• Pituitary infections are rare disorders caused by bacterial, viral, fungal and parasitic infections.

• Pituitary fungal infections usually occur in immunocompromised patients.

• Cushing’s syndrome, as immunosuppression factor, predisposes patients to infectious diseases, including fungal infections.

• Diagnosis of pituitary fungal infection is often achieved during histopathological investigation.

• Treatment with systemic anti-fungal drugs is controversial.

• Endocrine evaluation is recommended at the time of initial presentation of pituitary manifestations.

Summary

Ectopic adrenocorticotropic hormone (ACTH) production is an uncommon cause of Cushing’s syndrome and, rarely, the source can be a phaeochromocytoma. A 55-year-old man presented following an episode of presumed gastroenteritis with vomiting and general malaise. Further episodes of diarrhoea, joint pains and palpitations followed. On examination, he was hypertensive with no clinical features to suggest hypercortisolaemia. He was subsequently found to have raised plasma normetanephrines of 3.98 nmol/L (NR <0.71) and metanephrines of 0.69 nmol/L (NR <0.36). An adrenal CT showed a 3.8 cm right adrenal nodule, which was not MIBG-avid but was clinically and biochemically consistent with a phaeochromocytoma. He was started on alpha blockade and referred for right adrenalectomy. Four weeks later, on the day of admission for adrenalectomy, profound hypokalaemia was noted (serum potassium 2.0 mmol/L) with non-specific ST-segment ECG changes. He was also diagnosed with new-onset diabetes mellitus (capillary blood glucose of 28 mmol/L). He reported to have gained weight and his skin had become darker over the course of the last 4 weeks. Given these findings, he underwent overnight dexamethasone suppression testing, which showed a non-suppressed serum cortisol of 1099 nmol/L. Baseline serum ACTH was 273 ng/L. A preliminary diagnosis of ectopic ACTH secretion from the known right-sided phaeochromocytoma was made and he was started on metyrapone and insulin. Surgery was postponed for 4 weeks. Following uncomplicated laparoscopic adrenalectomy, the patient recovered with full resolution of symptoms.

Learning points:

• Phaeochromocytomas are a rare source of ectopic ACTH secretion. A high clinical index of suspicion is therefore required to make the diagnosis.

• Ectopic ACTH secretion from a phaeochromocytoma can rapidly progress to severe Cushing’s syndrome, thus complicating tumour removal.

• Removal of the primary tumour often leads to full recovery.

• The limited literature suggests that the presence of ectopic Cushing’s syndrome does not appear to have any long-term prognostic implications.

Summary

Primary adrenal lymphoma (PAL) is a rare cause of adrenal insufficiency. More than 90% is of B-cell origin. The condition is bilateral in up to 75% of cases, with adrenal insufficiency in two of three patients. We report two cases of adrenal insufficiency presenting at the age of 70 and 79 years, respectively. Both patients had negative 21-hydroxylase antibodies with bilateral adrenal lesions on CT. Biopsy showed B-cell lymphoma. One of the patients experienced intermittent disease regression on replacement dosage of glucocorticoids.

Learning points:

• Primary adrenal lymphoma (PAL) is a rare cause of adrenal insufficiency.

• Bilateral adrenal masses of unknown origin or in individuals with suspected extra-adrenal malignancy should be biopsied quickly when pheochromocytoma is excluded biochemically.

• Steroid treatment before biopsy may affect diagnosis.

• Adrenal insufficiency with negative 21-hydroxylase antibodies should be evaluated radiologically.

Summary

ACTH-secreting pheochromocytoma is a very rare cause of Cushing’s syndrome, with a high morbidity and mortality risk due to both cortisol and catecholamines excess. We report the case of a 45-year-old female patient with a 3 cm, high-density, left adrenal mass, diagnosed as an ACTH-secreting pheochromocytoma. The biochemical sensitivity of the tumor to somatostatin analogues was tested by a 100 μg s.c. octreotide administration, which led to an ACTH and cortisol reduction of 50 and 25% respectively. In addition to alpha and beta blockers, preoperative approach to laparoscopic adrenalectomy included octreotide, a somatostatin analogue, together with ketoconazole, in order to achieve an adequate pre-surgical control of cortisol release. Histopathological assessment confirmed an ACTH-secreting pheochromocytoma expressing type 2 and 5 somatostatin receptors (SSTR-2 and -5).

Learning points:

• ACTH-secreting pheochromocytomas represent a rare and severe condition, characterized by high morbidity and mortality risk.

• Surgical removal of the adrenal mass is the gold standard treatment, but adequate medical therapy is required preoperatively to improve the surgical outcome and to avoid major complications.

• Somatostatin analogs, in addition to other medications, may represent a useful therapeutic option for the presurgical management of selected patients.

• In this sense, the octreotide challenge test is a useful tool to predict favorable therapeutic response to the treatment.