Summary

Single-minded homolog 1 (SIM1) is a transcription factor that plays a role in the development of both the hypothalamus and pituitary. SIM1 gene mutations are known to cause obesity in humans, and chromosomal deletions encompassing SIM1 and other genes necessary for pituitary development can cause a Prader–Willi-like syndrome with obesity and hypopituitarism. There have been no reported cases of hypopituitarism linked to a single SIM1 mutation. A 21-month-old male presented to endocrinology clinic with excessive weight gain and severe obesity. History was also notable for excessive drinking and urination. Endocrine workup revealed central hypothyroidism, partial diabetes insipidus, and central adrenal insufficiency. Genetic evaluation revealed a novel mutation in the SIM1 gene. No other genetic abnormalities to account for his obesity and hypopituitarism were identified. While we cannot definitively state this mutation is pathogenic, it is notable that SIM1 plays a role in the development of all three of the patient’s affected hormone axes. He is now 6 years old and remains on treatment for his pituitary hormone deficiencies and continues to exhibit excessive weight gain despite lifestyle interventions.

Learning points:

• Mutations in SIM1 are a well-recognized cause of monogenic human obesity, and there have been case reports of Prader–Willi-like syndrome and hypopituitarism in patients with chromosomal deletions that contain the SIM1 gene.

• SIM1 is expressed during the development of the hypothalamus, specifically in neuroendocrine lineages that give rise to the hormones oxytocin, arginine vasopressin, thyrotropin-releasing hormone, corticotropin-releasing hormone, and somatostatin.

• Pituitary testing should be considered in patients with severe obesity and a known genetic abnormality affecting the SIM1 gene, particularly in the pediatric population.

Summary

Thyroid storm (TS) is a life-threatening condition that may suffer thyrotoxic patients. Therapeutic plasma exchange (TPE) is a rescue approach for TS with acute hepatic failure, but it should be initiated with careful considerations. We present a 55-year-old male patient with untreated Graves’ disease who developed TS. Severe hyperthyroidism and refractory atrial fibrillation with congestive heart failure aggregated to multiple organ failure. The patient was recovered by intensive multimodal therapy, but we had difficulty in introducing TPE treatment considering the risk of exacerbation of congestive heart failure due to plasma volume overload. In addition, serum total bilirubin level was not elevated in the early phase to the level of indication for TPE. The clinical course of this patient instructed delayed elevation of bilirubin until the level of indication for TPE in some patients and also demonstrated the risk of exacerbation of congestive heart failure by TPE.

Learning points:

• Our patient with thyroid storm could be diagnosed and treated promptly using Japan Thyroid Association guidelines for thyroid storm.

• Delayed elevation of serum bilirubin levels could make the decision of introducing therapeutic plasma exchange difficult in cases of thyroid storm with acute hepatic failure.

• The risk of worsening congestive heart failure should be considered carefully when performing therapeutic plasma exchange.

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

Gonadotropin-releasing hormone (GnRH) agonists, currently used in the treatment of advanced prostate cancer, have been described as a rare cause of pituitary apoplexy, a potentially life-threatening clinical condition. We report the case of a 69-year-old man with a known pituitary macroadenoma who was diagnosed with prostate cancer and started treatment with GnRH agonist leuprorelin (other hormones were not tested before treatment). Few minutes after drug administration, the patient presented with acute-onset severe headache, followed by left eye ptosis, diplopia and vomiting. Pituitary MRI revealed tumor enlargement and T1-hyperintense signal, compatible with recent bleeding sellar content. Laboratory endocrine workup was significant for low total testosterone. The patient was managed conservatively with high-dose steroids, and symptoms significantly improved. This case describes a rare phenomenon, pituitary apoplexy induced by GnRH agonist. We review the literature regarding this condition: the pathophysiological mechanism involved is not clearly established and several hypotheses have been proposed. Although uncommon, healthcare professionals and patients should be aware of this complication and recognize the signs, preventing a delay in diagnosis and treatment.

Learning points:

• Pituitary apoplexy (PA) is a potentially life-threatening complication that can be caused by gonadotropin-releasing hormone agonist (GnRHa) administration for the treatment of advanced prostate cancer.

• This complication is rare but should be taken into account when using GnRHa, particularly in the setting of a known pre-existing pituitary adenoma.

• PA presents with classic clinical signs and symptoms that should be promptly recognized.

• Patients should be instructed to seek medical care if suspicious symptoms occur.

• Healthcare professionals should be aware of this complication, enabling its early recognition, adequate treatment and favorable outcome.

Summary

The etiology of hyponatremia is assessed based on urine osmolality and sodium. We herein describe a 35-year-old Asian man with pulmonary tuberculosis and perforated duodenal ulcer who presented with hyponatremia with hourly fluctuating urine osmolality ranging from 100 to 600 mosmol/kg, which resembled urine osmolality observed in typical polydipsia and SIADH simultaneously. Further review revealed correlation of body temperature and urine osmolality. Since fever is a known non-osmotic stimulus of ADH secretion, we theorized that hyponatremia in this patient was due to transient ADH secretion due to fever. In our case, empiric exogenous glucocorticoid suppressed transient non-osmotic ADH secretion and urine osmolality showed highly variable concentrations. Transient ADH secretion-related hyponatremia may be underrecognized due to occasional empiric glucocorticoid administration in patients with critical illnesses. Repeatedly monitoring of urine chemistries and interpretation of urine chemistries with careful review of non-osmotic stimuli of ADH including fever is crucial in recognition of this etiology.

Learning points:

• Hourly fluctuations in urine osmolality can be observed in patients with fever, which is a non-osmotic stimulant of ADH secretion.

• Repeated monitoring of urine chemistries aids in the diagnosis of the etiology underlying hyponatremia, including fever, in patients with transient ADH secretion.

• Glucocorticoid administration suppresses ADH secretion and improves hyponatremia even in the absence of adrenal insufficiency; the etiology of hyponatremia should be determined carefully in these patients.

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

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

Papillary thyroid gland carcinoma is the most common type of malignancy of the endocrine system. Metastases to the pituitary gland have been described as a complication of papillary thyroid cancer in few reported cases since 1965. We report the case of a 68-year-old female patient with a well-differentiated form of thyroid gland cancer. Despite it being the most common malignant cancer of the endocrine system, with its papillary form being one of the two most frequently diagnosed thyroid cancers, the case we present is extremely rare. Sudden cardiac arrest during ventricular fibrillation occurred during hospitalization. Autopsy of the patient revealed papillary carcinoma of the thyroid, follicular variant, with metastasis to the sella turcica, and concomitant sarcoidosis of heart, lung, and mediastinal and hilar lymph nodes. Not only does atypical metastasis make our patient’s case most remarkable, but also the postmortem diagnosis of sarcoidosis makes her case particularly unusual.

Learning points:

• The goal of presenting this case is to raise awareness of the clinical heterogeneity of papillary cancer and promote early diagnosis of unexpected metastasis and coexisting diseases to improve clinical outcomes.

• Clinicians must be skeptical. They should not fall into the trap of diagnostic momentum or accept diagnostic labels at face value. Regardless of the potential mechanisms, clinicians should be aware of the possibility of the coexistence of thyroid cancer and sarcoidosis as a differential diagnosis of lymphadenopathy.

• This case highlights the importance of the diagnostic and therapeutic planning process and raises awareness of the fact that one uncommon disease could be masked by another extremely rare disorder.

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.