Summary

ACTH-secreting pituitary adenomas causing Cushing’s disease (CD) typically present with weight gain, whereas weight loss and hypokalemia in endogenous Cushing’s patients are suggestive of ectopic ACTH production. We report a case of CD presenting with atypical features of marked weight loss and hypokalemia. A 75-year-old female was admitted to the hospital with a history of profound weight loss, associated with uncontrolled hypertension, hyperglycemia, severe proximal muscle weakness, and hypokalemia. Subsequent investigations, including 24-h urinary free cortisol, 48-h low-dose dexamethasone suppression test, MRI of the sella, and bilateral inferior petrosal sinus sampling, confirmed CD without any evidence of ectopic ACTH production. She became eucortisolemic with medical therapy of ketoconazole and cabergoline, subsequently regained her weight, and became normokalemic. This case illustrates that patients with CD may present with symptoms and biochemical findings that would otherwise suggest ectopic ACTH production.

Learning points

• Patients with CD do not always present with classical clinical features and may present with symptoms and biochemical findings that would otherwise suggest ectopic ACTH production.

• While most patients with CD typically lose weight after biochemical remission, some patients gain weight after the normalization of cortisol levels.

• This case highlights the need to entertain a broad differential in patients presenting with hypokalemia and weight loss and the need to exclude hypercortisolemia.

Summary

We report a case of a 59-year-old woman with Cushing’s disease who developed hyperthyroidism following treatment of hypercortisolaemia. The patient with a history of recurrent hospitalisations caused by multi-sited soft tissue abscesses was admitted with sepsis. Both her medical history and physical examination suggested Cushing’s syndrome. The initial hormonal diagnostic process, conducted after sepsis treatment, brought forth conflicting results. However, hormonal assessment repeated 3 months later indicated pituitary hypercortisolaemia, which was confirmed through bilateral inferior petrosal sinus sampling and was successfully treated with transsphenoidal pituitary surgery. Three months after the surgery, the patient was readmitted to our epartment with symptoms of hyperthyroidism, which was confirmed by laboratory tests. Thyroid scintiscans indicated Graves’ disease. However, the absence of anti-thyroid stimulating hormone antibodies suggested other etiologies of hyperthyroidism. Eventually, the patient underwent radioiodine therapy. Currently, her condition is improving and she has had no recurrence of abscesses, severe infections, or hyperthyroidism. In conclusion, while clinical manifestation of hypercortisolaemia might be non-specific, its treatment may trigger the development of autoimmune diseases.

Learning points

• The presence of recurrent severe infections should prompt physicians to consider the possibility of hypercortisolaemia.

• Chronic hypercortisolism is debilitating and can lead to significant disability.

• Dexamethasone suppression testing in patients with active or recent severe inflammatory or infectious illnesses may produce misleading or confusing results.

• Clinicians should be aware of the potential development of autoimmune diseases following successful treatment of hypercortisolaemia.

Summary

Gonadotroph adenomas are the most common type of nonfunctional pituitary adenomas. However, functioning gonadotroph adenomas causing clinical manifestations are rare. We present the case of a 42-year-old man with an incidental finding of a pituitary gland mass. A pituitary MRI revealed a 3 cm macroadenoma, and laboratory investigations revealed elevated follicle-stimulating hormone (FSH) and total testosterone levels. A diagnosis of functioning FSH-secreting pituitary adenoma was considered, with possible concomitant luteinizing hormone secretion, given the elevated testosterone, prompting further evaluation. Testicular ultrasound showed bilaterally enlarged testicles, and visual field testing revealed a monocular superior temporal defect. Transsphenoidal resection of pituitary adenoma was the treatment of choice. Histopathology assessment confirmed the diagnosis of gonadotroph-secreting adenoma, with positive staining for FSH. Within the 12-week postoperative period, FSH and testosterone levels normalized, and the patient experienced significant improvement in vision, along with the resolution of macroorchidism. While functional gonadotroph adenomas are rare, patients can present with a wide range of symptoms that are often unnoticeable due to their slow development. Careful evaluation can help guide multidisciplinary management to achieve full remission.

Learning points

• Endocrine evaluation is indicated in all cases of pituitary incidentalomas to determine functional status.

• Clinically functioning gonadotroph adenomas, while rare, pose a diagnostic challenge and require careful clinical evaluation.

• Transsphenoidal surgery is the mainstay of treatment of functioning gonadotroph adenomas, with the involvement of a multidisciplinary team to achieve desirable outcomes.

Summary

Functioning gonadotroph adenomas with clinical manifestations are extremely rare and the majority of these are FSH-secreting macroadenomas. Clinical symptoms are due to excess gonadotrophins and sex hormones, and these may be present for a long time before the diagnosis of pituitary adenoma is made. We present the case of a 37-year-old Caucasian male with clinical manifestations of an FSH-secreting pituitary macroadenoma. He had sexual dysfunction for a year followed by bilateral testicular pain and enlargement which was initially treated as suspected recurrent epididymitis, but his symptoms did not resolve. He presented a year later with headaches and bilateral superior temporal visual field defects. Brain imaging confirmed a pituitary macroadenoma with optic chiasm compression. Pituitary profile demonstrated an unusually high FSH with high normal LH and normal testosterone level. The patient successfully underwent transsphenoidal hypophysectomy and histology confirmed gonadotroph differentiation and immunoreactivity predominantly with FSH. Gonadotrophin levels and testosterone dropped significantly after surgery, and he was started on testosterone replacement. MR imaging, 2 years post surgery, showed no recurrence of pituitary adenoma. In conclusion, testicular enlargement and hypogonadal symptoms associated with low testosterone levels are recognised features in FSH-secreting pituitary adenomas. Our patient had hypogonadal symptoms but consistently high normal testosterone levels prior to surgery. The reason for low libido despite high testosterone is unclear. Our case highlights the need to suspect such rare underlying pituitary pathology when dealing with unusual combinations of hypogonadal symptoms, testicular enlargement with low or normal testosterone levels.

Learning points

• Functioning pituitary adenomas that secrete excess follicle-stimulating hormone (FSH) are very rare and often present with symptoms related to pituitary mass effect.

• Testicular enlargement alongside sexual dysfunction are commonly reported symptoms amongst male patients.

• Pituitary profile results demonstrate a raised FSH level with either a low, normal, or even high testosterone level which may not always correlate to clinical symptoms.

• Pituitary pathology should be considered in males presenting with unusual combinations of testicular enlargement and hypogonadal symptoms even with normal testosterone levels.

Summary

Pituitary tuberculoma is extremely rare and may pose as a diagnostic challenge especially when encountered as an isolated lesion without other systemic manifestation of tuberculosis. A 21-year-old female was admitted for diabetic ketoacidosis. On the third day of admission following the resolution of diabetic ketoacidosis she developed a sudden onset of headache and blurring of vision suggestive of pituitary apoplexy. An urgent MRI brain revealed a large sellar mass with erosion into the sphenoid sinus and intracranial vasculitis. Transphenoidal surgery was done for tumour debulking which allowed histopathological examination of the sellar mass. Immunohistochemical examination of the sellar mass was positive for Gene Xpert MTB/Rif suggesting a tuberculoma. Anti-tuberculous therapy was commenced with full recovery of pituitary hormonal profile seen 7 months post-treatment. In regions with a high incidence of tuberculosis, a tuberculoma should be a considered in a diagnostic evaluation of a sellar lesion.

Learning points

• In an endemic area of tuberculosis, tuberculoma should be considered as a differential diagnosis when evaluating sellar lesions.

• Pituitary tuberculoma can present with pituitary apoplexy-like symptoms.

• Prompt diagnosis and treatment may lead to recovery of pituitary function.

Summary

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can impair pituitary–gonadal axis and a higher prevalence of hypogonadism in post-coronavirus disease 2019 (COVID-19) patients compared with the general population has been highlighted. Here we report the first case of a patient affected with a long-COVID syndrome leading to hypogonadism and treated with testosterone replacement therapy (TRT) and its effects on clinical and quality of life (QoL) outcomes. We encountered a 62-year-old man who had been diagnosed with hypogonadotropic hypogonadism about 2 months after recovery from COVID-19 underwent a complete physical examination, general and hormonal blood tests, and self-reported questionnaires administration before and after starting TRT. Following the TRT, both serum testosterone level and hypogonadism-related symptoms were improved, but poor effects occurred on general and neuropsychiatric symptoms and QoL. Therefore, hypogonadism does not appear to be the cause of neurocognitive symptoms, but rather a part of the long-COVID syndrome; as a consequence, starting TRT can improve the hypogonadism-related symptoms without clear benefits on general clinical condition and QoL, which are probably related to the long-COVID itself. Longer follow-up might clarify whether post-COVID hypogonadism is a transient condition that can revert as the patient recovers from long-COVID syndrome.

Learning points

• Hypogonadism is more prevalent in post-COVID-19 patients compared with the general population.

• In these patients, hypogonadism may be part of long-COVID syndrome, and it is still unclear whether it is a transient condition or a permanent impairment of gonadal function.

• Testosterone replacement therapy has positive effects on hypogonadism-related clinic without clear benefits on general symptomatology and quality of life, which are more likely related to the long-COVID itself.

Summary

IgG4-related disease is a multiorgan disorder in which nodules and hypertrophic lesions are observed simultaneously, or separately, in areas including the pancreas, liver, lungs, salivary glands, thyroid glands, and pituitary glands. IgG4-related hypophysis is one of several IgG4-related diseases and is characterized by pituitary gland and pituitary stalk thickening, various degrees of hypopituitarism, and increased serum IgG4 levels. Steroid therapy is effective for patients with IgG4-related hypophysis, but the reported effectiveness of steroid therapy for restoring pituitary function differs between studies. Following an episode of autoimmune pancreatitis 10 years prior, enlargement of the pituitary gland and stalk along with panhypopituitarism and polyuria developed in a 73-year-old male. A high serum IgG4 level and biopsy of the submandibular gland showing infiltration of IgG4-positive plasma cells led to a clinical diagnosis of IgG4-related hypophysitis. Prednisolone treatment reduced the swelling of the pituitary gland and stalk and improved anterior pituitary function. Although arginine vasopressin secretion remained insufficient, polyuria was relieved and kept in remission even after prednisolone treatment was completed. This is the first reported case in which prednisolone was able to maintain both normal anterior pituitary function and remission of polyuria caused by IgG4-related hypophysitis. IgG4-related hypophysitis has previously been associated with a relapse of symptoms during treatment. However, the patient reported in this case study remained in remission for over 3 months after completion of steroid treatment and should be monitored closely for changes in pituitary function.

Learning points

• Steroid therapy is the first-line therapy for pituitary dysfunction and pituitary stalk swelling in IgG4-related hypophysitis.

• In this case, although posterior pituitary function remained insufficient, polyuria was relieved and kept in remission for over 3 months even after prednisolone treatment was completed.

• IgG4-related hypophysitis has been associated with the relapse of symptoms during steroid tapering, and changes in pituitary function and symptoms should be monitored closely.

• When we encounter cases of adrenal insufficiency and polyuria during observation of autoimmune pancreatitis or other IgG4-related disease, we should consider the possibility of IgG4-related hypophysitis in mind.

Summary

This case report describes a rare presentation of ectopic Cushing’s syndrome (CS) due to ectopic corticotropin-releasing hormone (CRH) production from a medullary thyroid carcinoma (MTC). The patient, a 69-year-old man, presented with symptoms of muscle weakness, facial plethora, and easy bruising. An inferior petrosal sinus sampling test (IPSS) demonstrated pituitary adrenocorticotrophic hormone (ACTH) secretion, but a whole-body somatostatin receptor scintigraphy (⁶⁸Ga-DOTATOC PET/CT) revealed enhanced uptake in the right thyroid lobe which, in addition to a grossly elevated serum calcitonin level, was indicative of an MTC. A ¹⁸F-DOPA PET/CT scan supported the diagnosis, and histology confirmed the presence of MTC with perinodal growth and regional lymph node metastasis. On immunohistochemical analysis, the tumor cell stained positively for calcitonin and CRH but negatively for ACTH. Distinctly elevated plasma CRH levels were documented. The patient therefore underwent thyroidectomy and bilateral adrenalectomy. This case shows that CS caused by ectopic CRH secretion may masquerade as CS due to a false positive IPSS test. It also highlights the importance of considering rare causes of CS when diagnostic test results are ambiguous.

Learning points

• Medullary thyroid carcinoma may secrete CRH and cause ectopic CS.

• Ectopic CRH secretion entails a rare pitfall of inferior petrosal sinus sampling yielding a false positive test.

• Plasma CRH measurements can be useful in selected cases.

Summary

There are very few reports of syndrome of inappropriate antidiuresis hormone secretion (SIADH) after receiving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine. Herein, we present the case of an 84-year-old woman who developed severe hyponatremia following the second administration of the SARS-CoV-2 mRNA vaccine. The patient presented with nausea, vomiting, and headache. Laboratory tests showed a plasma sodium level of 119 mmol/L. After receiving 500 mL of intravenous saline over a 2-h period, her plasma sodium level raised to 121 mmol/L, but her symptoms persisted. Considering that rapid plasma sodium correction was necessary, we started 3% saline solution overnight. Her plasma sodium level raised to 132 mmol/L and her symptoms completely resolved. Clinical and laboratory findings were consistent with a diagnosis of SIADH. In the absence of any other triggering factors, we concluded that the condition was likely associated with the vaccination. Clinicians should be aware of the potential for hyponatremia, particularly SIADH, associated with SARS-CoV-2 mRNA vaccination.

Learning points

• Reports of syndrome of inappropriate antidiuresis hormone secretion after receiving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination are limited.

• If nausea, headache, and confusion are observed immediately after SARS-CoV-2 vaccination, clinicians should consider the presence of hyponatremia.

• As similar case reports to date have presented with severe hyponatremia, prompt treatment may be required.

Summary

Cushing’s syndrome due to ectopic adrenocorticotropic hormone (ACTH) secretion (EAS) by a pheochromocytoma is a challenging condition. A woman with hypertension and an anamnestic report of a ‘non-secreting’ left adrenal mass developed uncontrolled blood pressure (BP), hyperglycaemia and severe hypokalaemia. ACTH-dependent severe hypercortisolism was ascertained in the absence of Cushingoid features, and a psycho-organic syndrome developed. Brain imaging revealed a splenial lesion of the corpus callosum and a pituitary microadenoma. The adrenal mass displayed high uptake on both ¹⁸F-FDG PET/CT and ⁶⁸Ga-DOTATOC PET/CT; urinary metanephrine levels were greatly increased. The combination of antihypertensive drugs, high-dose potassium infusion, insulin and steroidogenesis inhibitor normalized BP, metabolic parameters and cortisol levels; laparoscopic left adrenalectomy under intravenous hydrocortisone infusion was performed. On combined histology and immunohistochemistry, an ACTH-secreting pheochromocytoma was diagnosed. The patient's clinical condition improved and remission of both hypercortisolism and catecholamine hypersecretion ensued. Brain magnetic resonance imaging showed a reduction of the splenial lesion. Off-therapy BP and metabolic parameters remained normal. The patient was discharged on cortisone replacement therapy for post-surgical hypocortisolism. EAS due to pheochromocytoma displays multifaceted clinical features and requires prompt diagnosis and multidisciplinary management in order to overcome the related severe clinical derangements.

Learning points

• A small but significant number of cases of adrenocorticotropic hormone (ACTH)-dependent Cushing’s syndrome are caused by ectopic ACTH secretion by neuroendocrine tumours, which is usually associated with severe hypercortisolism causing severe clinical and metabolic derangements.

• Ectopic ACTH secretion by a pheochromocytoma is exceedingly rare but can be life-threatening, owing to the simultaneous excess of both cortisol and catecholamines.

• The combination of biochemical and hormonal testing and imaging procedures is mandatory for the diagnosis of ectopic ACTH secretion, and in the presence of an adrenal mass, the possibility of an ACTH-secreting pheochromocytoma should be taken into account.

• Immediate-acting steroidogenesis inhibitors are required for the treatment of hypercortisolism, and catecholamine excess should also be appropriately managed before surgical removal of the tumour.

• A multidisciplinary approach is required for the treatment of this challenging entity.