Summary

Familial nonautoimmune hyperthyroidism (FNAH) is rare and occurs due to a constitutively activating thyroid-stimulating hormone receptor (TSHR) germline mutation. Forty-one families with FNAH have been reported so far. In the study, 17 of 41 families were not diagnosed with FNAH until three generations or more were described with hyperthyroidism. We report a case of FNAH diagnosed in the third generation. The index patient was diagnosed with hyperthyroidism at age 3. Large fluctuations in thyroid hormone levels occurred during anti-thyroid drug treatment, and he developed a goiter. The patient’s mother had similar history, requiring two surgical interventions and radioiodine treatment. The younger brother of the index patient did not experience large thyroid hormone level fluctuations, nor increased thyroid growth. A heterozygous TSHR c.1357A>G mutation, resulting in a M453V amino acid exchange, was detected in all three patients leading to FNAH diagnosis, with complete genotype–phenotype segregation. Based on Sorting intolerant from tolerant (SIFT) and PolyPhen2 scores of 0.01 and 0.99, respectively, an effect on protein function can be assumed. As illustrated by this family with FNAH, total thyr oidectomy is necessary for patients with nonautoimmune hyperthyroidism. Development of goiter is common, anti-thyroid drug treatment is often difficult, and remission of hyperthyroidism does not occur after discontinuation of anti-thyroid drug treatment. Thus, early diagnosis and appropriate treatment of FNAH is necessary to avoid predictable, unnecessary complications and further surgical interventions.

Learning points

• In the study, 19/42 cases of familial nonautoimmune hyperthyroidism (FNAH), including the reported case, were not diagnosed as FNAH until the third generation; this lead to suboptimal treatment and frequent relapses of nonautoimmune hyperthyroidism (NAH).

• Detection of thyroid-stimulating hormone receptor (TSHR) mutations in patients with suspected FNAH to confirm diagnosis is essential to ensure proper treatment for the patient and further affected family members.

• NAH will persist without proper treatment by total thyroidectomy.

• Symptoms and age of onset may vary between family members

• All family members with a TSHR germline mutation should be monitored with thyroid-stimulating hormone and for symptoms throughout their lives.

Summary

Here, we describe a case of a patient presenting with adrenocorticotrophic hormone-independent Cushing’s syndrome in a context of primary bilateral macronodular adrenocortical hyperplasia. While initial levels of cortisol were not very high, we could not manage to control hypercortisolism with ketoconazole monotherapy, and could not increase the dose due to side effects. The same result was observed with another steroidogenesis inhibitor, osilodrostat. The patient was finally successfully treated with a well-tolerated synergitic combination of ketoconazole and osilodrostat. We believe this case provides timely and original insights to physicians, who should be aware that this strategy could be considered for any patients with uncontrolled hypercortisolism and delayed or unsuccessful surgery, especially in the context of the COVID-19 pandemic.

Learning points

• Ketoconazole–osilodrostat combination therapy appears to be a safe, efficient and well-tolerated strategy to supress cortisol levels in Cushing syndrome.

• Ketoconazole and osilodrostat appear to act in a synergistic manner.

• This strategy could be considered for any patient with uncontrolled hypercortisolism and delayed or unsuccessful surgery, especially in the context of the COVID-19 pandemic.

• Considering the current cost of newly-released drugs, such a strategy could lower the financial costs for patients and/or society.

Summary

Hypoparathyroidism is characterized by low or inappropriately normal parathormone production, hypocalcemia and hyperphosphatemia. Autosomal dominant hypocalcemia (ADH) type 1 is one of the genetic etiologies of hypoparathyroidism caused by heterozygous activating mutations in the calcium-sensing receptor (CASR) gene. Current treatments for ADH type 1 include supplementation with calcium and active vitamin D. We report a case of hypoparathyroidism in an adolescent affected by syncope without prodrome. The genetic testing revealed a variant in the CASR gene. Due to standard therapy ineffectiveness, the patient was treated with recombinant human parathyroid hormone (1–34), magnesium aspartate and calcitriol. He remained asymptomatic and without neurological sequelae until adulthood. Early diagnosis and treatment are important to achieve clinical stability.

Learning points

• Autosomal dominant hypocalcemia (ADH) type 1 is one of the genetic etiologies of hypoparathyroidism caused by heterozygous activating mutations in the calcium-sensing receptor (CASR) gene.

• The variant c.368T>C (p.Leu123Ser) in heterozygosity in the CASR gene is likely pathogenic and suggests the diagnosis of ADH type 1.

• Teriparatide (recombinant human parathyroid hormone 1–34) may be a valid treatment option to achieve clinical stability for those individuals whose condition is poorly controlled by current standard therapy.

Summary

Feminizing estrogen-secreting adrenocortical carcinomas (ACCs) are exceedingly rare and carry a poor prognosis. The most common presenting trait is gynecomastia, but enlarged breasts are also a frequent clinical finding in healthy men. Biochemical evaluation may be challenging. As such, there is a high risk of delayed diagnosis and treatment opportunity. Here, we present a case with an estrogen-producing ACC where the abnormal steroid profile obtained at the time of initial workup was essential for the prompt diagnosis. Wider adoption of liquid chromatography mass spectrometry-based steroid assays has potential to improve early diagnosis of feminizing estrogen-secreting ACC.

Learning points

• Feminizing estrogen-secreting adrenocortical carcinomas (ACCs) are a rare, but an important differential diagnosis in men with rapidly developing gynecomastia.

• Biochemical evaluation is essential for a prompt diagnosis.

• Steroid hormone profiling using liquid chromatography mass spectrometry technology has the potential to improve early diagnosis of feminizing estrogen-secreting ACC.

Summary

Drinking fruit juice is an increasingly popular health trend, as it is widely perceived as a source of vitamins and nutrients. However, high fructose load in fruit beverages can have harmful metabolic effects. When consumed in high amounts, fructose is linked with hypertriglyceridemia, fatty liver and insulin resistance. We present an unusual case of a patient with severe asymptomatic hypertriglyceridemia (triglycerides of 9182 mg/dL) and newly diagnosed type 2 diabetes mellitus, who reported a daily intake of 15 L of fruit juice over several weeks before presentation. The patient was referred to our emergency department with blood glucose of 527 mg/dL and glycated hemoglobin (HbA1c) of 17.3%. Interestingly, features of diabetic ketoacidosis or hyperosmolar hyperglycemic state were absent. The patient was overweight with an otherwise unremarkable physical exam. Lipase levels, liver function tests and inflammatory markers were closely monitored and remained unremarkable. The initial therapeutic approach included i.v. volume resuscitation, insulin and heparin. Additionally, plasmapheresis was performed to prevent potentially fatal complications of hypertriglyceridemia. The patient was counseled on balanced nutrition and detrimental effects of fruit beverages. He was discharged home 6 days after admission. At a 2-week follow-up visit, his triglyceride level was 419 mg/dL, total cholesterol was 221 mg/dL and HbA1c was 12.7%. The present case highlights the role of fructose overconsumption as a contributory factor for severe hypertriglyceridemia in a patient with newly diagnosed diabetes. We discuss metabolic effects of uncontrolled fructose ingestion, as well as the interplay of primary and secondary factors, in the pathogenesis of hypertriglyceridemia accompanied by diabetes.

Learning points

• Excessive dietary fructose intake can exacerbate hypertriglyceridemia in patients with underlying type 2 diabetes mellitus (T2DM) and absence of diabetic ketoacidosis or hyperosmolar hyperglycemic state.

• When consumed in large amounts, fructose is considered a highly lipogenic nutrient linked with postprandial hypertriglyceridemia and de novo hepatic lipogenesis (DNL).

• Severe lipemia (triglyceride plasma level > 9000 mg/dL) could be asymptomatic and not necessarily complicated by acute pancreatitis, although lipase levels should be closely monitored.

• Plasmapheresis is an effective adjunct treatment option for rapid lowering of high serum lipids, which is paramount to prevent acute complications of severe hypertriglyceridemia.

Summary

Graves’ disease is an autoimmune condition leading to the activation of and an increase in thyroid hormone secretion. Manifestations of hyperthyroidism in Graves’ disease can vary among people. In this case, we report a 24-year-old Thai man with a rare presentation of unilateral gynecomastia along with symptoms of thyrotoxicosis. Physical examination revealed a 3 cm non-tender palpable glandular tissue beneath and around the left areola without nipple discharge and moderately diffuse thyroid enlargement with thyroid bruit. Thyroid function test showed a typical thyrotoxicosis state with elevated serum-free T4 and decreased serum TSH. His diagnosis of Graves’ disease was confirmed biochemically with a highly elevated anti-TSH receptor antibody. Early treatment with anti-thyroid medication was given first, followed by Radioiodine treatment (RAI) for definitive treatment due to high level of anti-TSH receptor antibody, enlarged thyroid and severe thyrotoxicosis presentation at a young age, which might not resolve by anti-thyroid medication alone. The patient responded well to treatment and achieved complete resolution of unilateral gynecomastia with clinically and biochemically euthyroid within 3 months after treatment. No recurrent gynecomastia was found during the 2-year follow-up.

Learning points

• Characteristic of gynecomastia in hyperthyroidism is usually presented with bilateral progressive gynecomastia; however, unilateral gynecomastia is occasionally found as a presentation of hyperthyroidism.

• Complete resolution of gynecomastia without recurrence can be achieved within a few months of treatment after thyrotoxicosis is resolved in patients with hyperthyroidism with the recent development of gynecomastia.

• RAI for definitive treatment is recommended in young adult patients expressing very high anti-TSH antibody level with severe thyrotoxicosis.

Summary

We report concurrent metastatic prostatic adenocarcinoma (PC) and functioning androgen-secreting adrenocortical carcinoma (ACC) in a 77-year-old man. The failure to achieve adequate biochemical castration via androgen deprivation therapy (ADT) as treatment for PC metastases, together with elevated DHEA-S, androstenedione, and discordant adrenal tracer uptake on FDG-PET and PSMA-PET, suggested the presence of a concurrent functional primary adrenal malignancy. On histopathological analysis, scant foci of PC were present throughout the ACC specimen. Castration was achieved post adrenalectomy with concurrent drop in prostate-specific antigen. We outline the literature regarding failure of testosterone suppression on ADT and salient points regarding diagnostic workup of functioning adrenal malignancies.

Learning points

• Failure to achieve castration with androgen deprivation therapy is rare and should prompt careful review to identify the underlying cause.

• All adrenal lesions should be evaluated for hormone production, as well as assessed for risk of malignancy (either primary or secondary).

• Adrenocortical carcinomas are commonly functional, and can secrete steroid hormones or their precursors (androgens, progestogens, glucocorticoids and mineralocorticoids).

• In this case, a co-incident, androgen-producing adrenocortical carcinoma was the cause of failure of testosterone suppression from androgen deprivation therapy as treatment for metastatic prostate cancer. Pathological adrenal androgen production contributed to the progression of prostate cancer.

Summary

Hyponatraemia is the most common electrolyte disturbance in hospitalised patients and is associated with numerous adverse outcomes. Patients with schizophrenia are particularly susceptible to hyponatraemia, in part due to the close association between this condition and primary polydipsia. We report the case of a 57-year-old woman with schizophrenia and primary polydipsia who was receiving inpatient psychiatric care. She became increasingly confused, had multiple episodes of vomiting, and collapsed 1 week after being commenced on quetiapine 300 mg. On examination, she was hypertensive and her Glasgow coma scale was nine. She had a fixed gaze palsy and a rigid, flexed posture. Investigations revealed extreme hyponatraemia with a serum sodium of 97 mmol/L. A CT brain demonstrated diffused cerebral oedema with sulcal and ventricular effacement. A urine sodium and serum osmolality were consistent with SIAD, which was stimulated by the introduction of quetiapine. The antidiuretic effect of vasopressin limited the kidney’s ability to excrete free water in response to the patients' excessive water intake, resulting in extreme, dilutional hyponatraemia. The patient was treated with two 100 mL boluses of hypertonic 3% saline but deteriorated further and required intubation. She had a complicated ICU course but went on to make a full neurological recovery. This is one of the lowest sodium levels attributed to primary polydipsia or second-generation antipsychotics reported in the literature.

Learning points

• The combination of primary polydipsia and SIAD can lead to a life-threatening, extreme hyponatraemia.

• SIAD is an uncommon side effect of second-generation anti-psychotics.

• Serum sodium should be monitored in patients with primary polydipsia when commencing or adjusting psychotropic medications.

• Symptomatic hyponatraemia is a medical emergency that requires treatment with boluses of hypertonic 3% saline.

• A serum sodium of less than 105 mmol/L is associated with an increased risk of osmotic demyelination syndrome, therefore the correction should not exceed 8 mmol/L over 24 h.

Summary

Immobilization-induced hypercalcemia is an uncommon cause of elevated calcium which is usually diagnosed following extensive systemic workup and exclusion of more common etiologies. Previously reported cases have largely described this phenomenon in adolescents and young adults a few weeks to months after the initial onset of immobilization. Metabolic workup tends to demonstrate hypercalcemia, hypercalciuria, and eventual osteoporosis. While the exact mechanism remains largely unclear, a dysregulation between bone resorption and formation is central to the pathogenesis of this disease. Decreased mechanical loading from prolonged bedrest tends to increase osteoclast induced bone resorption while promoting osteocytes to secrete proteins such as sclerostin to reduce osteoblast mediated bone formation. We describe the case of an 18-year-old male who was admitted following intraabdominal trauma. He underwent extensive abdominal surgery including nephrectomy resulting in initiation of dialysis. After 6 months of hospitalization, the patient gradually began developing uptrending calcium levels. Imaging and laboratory workup were unremarkable for any PTH-mediated process, malignancy, thyroid disorder, adrenal disorder, or infection. Workup did reveal significant elevated bone turnover markers which in combination with the clinical history led the physicians to arrive at the diagnosis of immobilization induced hypercalcemia. In order to prevent decreased rates of bone loss, the patient was administered denosumab for treatment. Hypocalcemia followed treatment expectedly and was repleted with supplementation via the patient’s total parenteral nutrition.

Learning points

• Immobilization-induced hypercalcemia should remain as a differential diagnosis of patients with prolonged hospitalizations with hypercalcemia.

• Extensive workup of common etiologies of hypercalcemia should be considered prior to arriving at this diagnosis.

• Denosumab, while off-label for this usage, offers an effective treatment option for immobilization-induced hypercalcemia though it carries a risk of hypocalcemia especially among patients with renal disease.

Summary

A 32-year-old Caucasian male presented to the emergency department with a one-day history of acute severe bilateral lower limb weakness, three days after competing in a bodybuilding competition. He consumed large quantities of carbohydrate-rich foods following the competition. His past medical history was significant for anxiety, and family history was non-contributory. Examination was normal except for reduced power and hyporeflexia in both legs, despite his muscular physique. He was noted to have severe hypokalaemia (K⁺= 1.9 mmol/L). His thyroid function tests were consistent with thyrotoxicosis. He reported taking thyroxine and several other agents to facilitate muscle mass generation before the bodybuilding competition. His presentation was reminiscent of thyrotoxic periodic paralysis, albeit uncommon with Caucasian ethnicity. He also had transient hyperglycaemia at presentation with concomitant hyperinsulinaemia, which could be attributed to the carbohydrate load and may have exacerbated his hypokalaemia through a transcellular shift. Urine toxicology screen subsequently ruled out the use of diuretics but confirmed the presence of a long-acting beta agonist (clenbuterol) which, along with other substances, may have aggravated the hypokalaemia further. After 12 h of i.v. replacement, the potassium level normalised and leg weakness resolved. The patient agreed to stop taking thyroxine and beta agonists and was well during the clinic visit at one month follow-up. This case highlights the potential for thyrotoxicosis factitia to exacerbate hypokalaemia and muscle weakness from other causes in bodybuilders presenting with acute severe weakness, irrespective of ethnicity.

Learning points

• In patients presenting with muscle weakness and hypokalaemia, early consideration of thyrotoxicosis is essential, even in the absence of a past history of thyroid disease or specific symptoms of thyrotoxicosis, in order to allow prompt initiation of appropriate treatment and to prevent recurrence.

• Bodybuilders may constitute a uniquely ‘at-risk’ group for thyrotoxic periodic paralysis secondary to thyrotoxicosis factitia, especially where there is concomitant use of beta-adrenergic agonists, even in the absence of diuretic use.

• Although rare and usually described in patients of Asian or Polynesian ethnicity, this case highlights that thyrotoxic periodic paralysis secondary to thyrotoxicosis factitia can also occur in patients with Caucasian ethnicity.

• We speculate that consuming large quantities of carbohydrates may induce hyperinsulinaemia, which could theoretically contribute to worse hypokalaemia, though mechanistic studies would be needed to explore this further.