Summary

A 52-year-old female patient with breast cancer presented with a history of fatigue and malaise 1 year prior. She was diagnosed with isolated adrenocorticotropic hormone (ACTH) deficiency (IAD) on endocrinological examination. Her pituitary gland showed normal morphology. Paraneoplastic IAD associated with breast cancer was suspected; however, immunofluorescence staining revealed no ectopic ACTH or proopiomelanocortin expression in the tumor tissue. Subsequently, the patient was diagnosed with idiopathic acquired IAD concurrent with breast cancer, ruling out paraneoplastic syndrome. Although malignancy should be considered a potential cause of IAD, not all patients with concurrent IAD and malignancy necessarily develop paraneoplastic syndrome.

Learning points

• Several adrenal insufficiency symptoms are similar to the nonspecific symptoms associated with malignancies, and therefore, the diagnosis of IAD remains challenging, especially in patients with cancer.

• When we encounter a case of IAD accompanied by a malignant tumor, it is important to suspect that paraneoplastic IAD, a novel clinical condition as secondary hypophysitis, may be the etiologic agent.

• Although malignant tumours should be considered a potential cause of IAD, not all patients with concurrent IAD and malignancy necessarily develop paraneoplastic autoimmune hypophysitis.

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

At the end of the 19th century, an 18-year-old lady gave birth to a well-proportioned, though very small, son. After delivery, the mother developed a full-grown beard, whereas the son always remained of small stature. The mother developed diabetes mellitus and died, aged 59, from a complicated severe cold. The son died at the age of 91 because of chronic kidney disease. The differential diagnosis in the son is isolated growth hormone deficiency. The mother might have suffered luteoma of pregnancy, polycystic ovary syndrome (PCOS), or Sertoli–Leydig cell tumor(s). The two cases are apparently coincidental/not related in pathophysiology.

Learning points

• Hirsutism occurring directly postpartum can have several causes.

• Patients with isolated growth hormone deficiency can live a long life without the substitution of growth hormone.

• Coincidence does not necessarily imply correlation.

• In the past, patients with endocrine disorders like severe hirsutism or small stature were employed at circuses and fairs to entertain the audience as curiosities.

Summary

Thyroid-stimulating hormone-secreting pituitary adenomas (TSHomas) are rare, accounting for less than 1% of all pituitary adenomas. We present a case of hyperthyroidism secondary to a likely TSHoma and coexisting functional thyroid adenoma. Laboratory errors and familial abnormalities in thyroid function tests were ruled out, and a diagnosis of the toxic thyroid adenoma was confirmed on a thyroid uptake scan. However, the triiodothyronine suppression test was contraindicated due to the patient’s cardiovascular disease, and the thyrotropin-releasing hormone stimulation test, measurement of glycoprotein hormone alpha-subunit, and genetic testing were unavailable. Magnetic resonance imaging of the brain revealed a suprasellar pituitary macroadenoma measuring 40 mm × 20.3 mm × 17 mm. The patient was initiated on carbimazole; however, thyroid stimulating hormone and thyroxine levels remained elevated. The patient declined trans-sphenoidal surgery and was treated with radioactive iodine to manage the toxic thyroid adenoma, leading to reduced thyroxine levels and symptom improvement. Unfortunately, the patient passed away before long-acting somatostatin analogs became available. This case highlights the diagnostic and therapeutic challenges involved in managing thyrotoxicosis with dual etiology.

Learning points

• Hyperthyroidism can have multiple etiologies, which can coexist in the same patient.

• Persistent discordant thyroid function tests warrant further investigation.

• The gold standard for diagnosis of TSHomas remains immunohistochemical analysis of the tumor tissue.

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

A 48-year-old Asian male, presented to the hospital for an elective total thyroidectomy in the context of 6.3 cm thyroid nodule. The fine needle aspiration cytology of the nodule confirmed papillary thyroid cancer (PTC) with some atypical histiocytes. He has a history of idiopathic arginine vasopressin deficiency (AVP-D) and has been taking oral DDAVP 100 µg daily, self-adjusting the dose based on thirst and polyuria. Additionally, he also has a history of recurrent spontaneous pneumothorax. His total thyroidectomy was aborted due to significant intraoperative bleeding, and his admission was further complicated by post-operative hyponatraemic seizure. Thyroid histology revealed the diagnosis of Langerhans cell histiocytosis (LCH), and further investigation with contrast CT demonstrated multi-organ involvement of the thyroid, lungs, and bones.

Learning points

• Langerhans cell histiocytosis (LCH) is a condition that can affect one or more organ systems, including the pituitary, where it can present as AVP deficiency. Strict monitoring of fluid balance, as well as serial monitoring of serum sodium, is essential in all patients with AVP-D in the perioperative setting.

• Iatrogenic hyponatraemic seizure is an uncommon but serious complication of DDAVP treatment in hospitalised patients with AVP-D. DDAVP dosing must be carefully monitored.

• LCH with multisystem involvement is an important mimic for metastatic conditions, and histological diagnosis is essential to guide treatment and prognosis.

• Although LCH without bone marrow involvement is unlikely to increase the risk of bleeding, its effect on tissue integrity may make surgery more challenging.

• BRAF-V600E mutation is an important driver mutation and a potential therapeutic target in the treatment of LCH.

Summary

Functioning gonadotroph tumors are rare neoplasms that can cause ovarian hyperstimulation syndrome (OHSS) in women of reproductive age. Here, we present a case of a follicle-stimulating hormone (FSH)-producing pituitary neuroendocrine tumor (PitNET) with irregular menstrual cycles and OHSS in a Japanese woman. A 34-year-old woman with bilateral multi-cystic ovarian mass was referred to our hospital for ovarian surgery. The imaging feature of magnetic resonance imaging (MRI) of the ovary and elevated estradiol levels with normal FSH and low luteinizing hormone (LH) levels led us to suspect the presence of a functioning gonadotroph PitNET. MRI revealed a 19-mm pituitary tumor, and increased tracer uptake was observed in the pituitary lesion on ¹¹¹In-pentetreotide scintigraphy. Transsphenoidal tumor resection resulted in the resolution of the ovarian enlargement, normalization of her menstrual cycles, and spontaneous pregnancy. Immunohistochemistry (IHC) of the resected tumor for pituitary transcription factors, including steroidogenesis factor 1 (SF1) and estrogen receptor alpha, demonstrated positive immunoreactivity, whereas IHC for pituitary-specific positive transcription factor 1 was negative, suggesting that the tumor belonged to the SF1 lineage of PitNETs (gonadotroph tumor). The tumor cells showed positive expression of FSHβ, while LHβ was mostly negative. Consistent with the high pituitary tumor uptake observed on ¹¹¹In-pentetreotide scintigraphy, the pituitary tumor showed positive expression of somatostatin receptor 2A. Detailed clinical and histological evaluations will provide useful information to understand these rare functioning gonadotroph tumors better.

Learning points

• Functioning gonadotroph tumors are very rare neuroendocrine tumors of pituitary origin.

• Women of reproductive age presenting with bilateral multi-cystic ovarian enlargement, irregular menstrual cycles, and hyperestrogenemia under unsuppressed follicle-stimulating hormone (FSH) levels should be evaluated for FSH-producing tumor.

• Raising awareness of OHSS due to functioning gonadotroph tumors is crucial to prevent unnecessary ovarian surgery.

• Comprehensive histological analysis may provide useful information to better understand the characteristics of functioning gonadotroph tumors.

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.