Summary

We report the case of an 88-year-old man hospitalized for COVID-19 with persistently very high procalcitonin (proCt) levels despite infection resolution. Since proCt is an adjunct tumor marker in the diagnosis of medullary thyroid carcinoma (MTC), serum calcitonin (Ct) was also measured showing very high levels. Computed tomography (CT) scan showed the presence of a thyroid mass and neck ultrasound revealed a solid isoechoic, inhomogeneous, 50 mm nodule in the right thyroid lobe, extended into the mediastinum. Fine needle aspiration (FNA) of the thyroid nodule confirmed the diagnosis of MTC. An ¹⁸F-fluorodopa positron emission tomography/computed tomography (PET/CT) scan revealed the presence of distant metastases in ribs, vertebrae, in the right iliac wing and the liver. Since surgery was not feasible, the patient was started on cabozantinib 40 mg/dL. After 16 months the patient is still on cabozantinib at the same dose, he reports complete autonomy in daily life activities, and serum Ct is still elevated; however, the imaging evaluation does not show signs of disease progression.

Learning points

• High procalcitonin serum values despite the absence of infection are suggestive of MTC.

• Advanced MTC with multiple metastases can have an indolent course and can go unrecognized for years.

• Cabozantinib is a valuable option for the treatment of advanced MTC.

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

Brain metastases as the first clinical presentation of a papillary thyroid carcinoma (PTC) are exceptional, while cavernous angiomas are common cerebral malformations. We report the case of a 36-year-old male with an incidental brain lesion mimicking a cavernous angioma on MRI. Gamma knife radiosurgery was performed, but after 6 months, the patient developed neurological symptoms, and a repeat brain MRI revealed a significant increase in the mass. The patient underwent neurosurgery, and the histological examination of the lesion revealed metastatic carcinoma of thyroid origin. PET–CT and neck ultrasound, subsequently performed, were concordant for the presence of a right lobe nodule and ipsilateral lymph nodes, both with ultrasound features suspicious of malignancy. Total thyroidectomy with central and right lateral neck dissection was performed, and histology confirmed an intrathyroidal multifocal PTC with lymph node metastases. Postoperative radioiodine was administered, and focal uptake within the thyroid bed, without distant metastases or brain remnants, was found on the post-therapeutic whole-body scan. At 2 years from diagnosis, the patient is in good health and undergoes clinical and imaging follow-up.

Learning points

• Brain cavernous angiomas are common cerebral vascular malformations that are usually diagnosed by MRI.

• Despite the high accuracy of MRI, the exam is not pathognomonic, and misdiagnosis cannot be excluded.

• Brain metastases from PTC are very rare; however, they can mimic a cavernous angioma. Therefore, the differential diagnosis should always be considered.

Summary

Congenital adrenal hyperplasia (CAH) is one of the most common inherited rare endocrine disorders. This case report presents two female siblings with delayed diagnosis of non-classical CAH 3β-hydroxysteroid dehydrogenase type 2 (3βHSD2D/HSD3B2) despite early hospital admission and apparent CAH manifestations such as infections, hirsutism, menstrual disturbances, and PCOS phenotype. Initially, sister 1 was misdiagnosed with PCOS and then 11-hydroxylase deficiency (CYP11B1), based on ultrasound, biochemical findings, and negative genetic testing for 21-hydroxylase deficiency (CYP21A2). Additional diagnostic workup was performed when sister 2also presented with symptoms of androgen excess. Genetic testing for CAH/steroid disorders finally revealed that both siblings were compound heterozygous for two variants in the HSD3B2 gene: a frameshift variant, c.558dup, p.(Thr187Hisfs*17) and a novel missense variant, c.65T>C, p.(Leu22Ser). A Synacthen test showed an insufficient cortisol increase. In vitro studies of the variants in a cell model revealed loss of function for the p.(Thr187Hisfs*17) and partial activity for p.(Leu22Ser) confirming non-classic CAH. Overlapping symptomatology and lack of specialized knowledge on steroid biosynthesis and associated rarest forms of CAH may explain the delayed diagnosis. However, with newer diagnostic methods comprising a less biased approach, very rare forms of non-classical CAH may no longer be overlooked in the future.

Learning points

• Non-classic 3βHSD2 is likely underdiagnosed.

• Late diagnosis of mild non-classic 3βHSD2 does occur and one should be aware of this diagnosis.

• Early diagnosis of NCCAH may prevent many consequences such as severe hirsutism, prolonged menstrual irregularities, infertility, or even adrenal crisis with severe infections.

• Comprehensive steroid profiling and genetic testing should be used earlier, especially when in doubt about a diagnosis.

Summary

Riedel’s thyroiditis is the rarest form of thyroiditis, occasionally resulting in rapid thyroid enlargement and potential tracheal obstruction. Here, we detail the case of an 81-year-old woman with a medical history including Hodgkin lymphoma, Hashimoto’s thyroiditis, and multinodular goiter. She presented to the emergency room with stridor, cervical swelling, and breathing difficulties for over 2 days. CT scans revealed substantial thyroid enlargement causing significant glottal and tracheal compression, to a minimum tracheal diameter of 7 mm. Due to the severity of the compressive symptoms, orotracheal intubation and mechanical ventilation were deemed necessary. Surprisingly, despite the initial suspicion of malignancy given the rapid growth in the elderly, subsequent cytological and histological evaluations indicated a benign form of invasive fibrous thyroiditis – Riedel’s thyroiditis. Although surgical intervention was advised, the patient declined and opted for endobronchial treatment with a prosthetic stent and subsequent treatment with systemic glucocorticoids. Following successful treatment, she was discharged within a week and resumed normal activities without respiratory distress. This case is noteworthy for its rapid benign mass growth, rare emergent presentation, and the patient’s advanced age.

Learning points

• The rapid enlargement of the thyroid gland in elderly patients poses a diagnostic challenge, stemming from the higher occurrence of aggressive thyroid carcinomas.

• Despite the clinical presentation, a comprehensive diagnostic workup, including fine-needle aspiration and core-needle biopsy, is crucial for accurately distinguishing between benign and malignant causes of thyroid nodule enlargement.

• This case report illustrates diverse treatment options for Riedel’s thyroiditis, and the importance of individualized treatment plans based on the degree of airway obstruction, patient preferences, and response to initial interventions.

• Clinicians should contemplate the inclusion of glucocorticoids in the therapeutic regimen for Riedel’s thyroiditis, particularly in cases where surgical intervention is not feasible or declined by the patient.

Summary

Multiple endocrine neoplasia type 2 (MEN2) is a hereditary cancer syndrome caused by germline-activating pathogenic variants in the RET proto-oncogene. MEN2A is the most common subtype, with a risk for medullary thyroid cancer (MTC), pheochromocytoma (PHEO), and primary hyperparathyroidism (PHPT), whereas MEN2B is less common and associated with MTC and PHEO along with mucosal neuromas. Little is known about the specific RET germline heterozygous variant K666N. This variant has been described in very few families, and in most cases, patients were diagnosed with a very indolent MTC as the only feature. There is one case of MTC and bilateral PHEO. The RET K666N variant is not stratified yet by the American Thyroid Association, and data are limited on pathogenicity; therefore, appropriate screening and treatment of asymptomatic RET K666N carriers are unclear. Here, we report a family with a heterozygous germline RET K666N variant. The proband was identified when she experienced cardiogenic shock and multi-organ failure after an elective hysterectomy and subsequently was found to have PHEO, with genetic testing revealing the RET K666N germline variant. Patient consent was obtained through IRB protocol COMIRB #15-0516.

Learning Points

• The specific RET germline heterozygous variant K666N is rare and described in very few families, and in most cases, patients were diagnosed with a very indolent MTC as the only feature. Our proband is much younger and has PHEO, MTC, and PHPT.

• The RET K666N germline variant appears to be a low penetrance variant for MEN2.

Summary

Bariatric surgery is increasingly being accepted as a viable treatment for managing the growing obesity epidemic. Roux-en-Y gastric bypass (RYGB) is one of the most commonly performed procedures. Perforated duodenal ulcer following RYGB is a rare condition with a low incidence. We report a case of a patient with a perforated duodenal ulcer post RYGB, and the surgical approach. A 66-year-old man with hypertension and a history of laparoscopic RYGB for class III obesity was admitted to the emergency department with severe epigastric pain radiating to the right side of his abdomen and right shoulder, associated with nausea and vomiting. Computed tomography (CT) showed intraperitoneal free fluid, a thickened wall of the duodenum and free air, duodenal perforation was suspected. The patient underwent exploratory laparoscopy that revealed a perforated duodenal ulcer that was closed with an absorbable barbed suture and omental patch. Perforated ulcers in excluded segments after RYGB are a rare entity with a challenging diagnosis, and clinicians should be aware of and have a low threshold for diagnostic laparoscopy.

Learning points

• Roux-en-Y gastric bypass (RYGB) is one of the most commonly performed procedures in bariatric surgery.

• Perforated ulcers in excluded segments after RYGB are a rare entity with a challenging diagnosis.

• The pathophysiology of this perforation is not clear, but several mechanisms have been proposed. Helicobacter pylori has been implicated.

• Clinicians should be aware and have a low threshold for diagnostic laparoscopy for a patient who has acute abdominal pain after RYGB, despite negative diagnostic measures.

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

Pregnancy in the setting of metastatic paraganglioma is challenging, particularly in the context of tyrosine kinase use. We describe a 26-year-old female with a background of metastatic paraganglioma harboring a pathogenic SDHB variant, requiring sunitinib, which was withheld to facilitate the safe conception and delivery of a healthy baby. She required no alpha- or beta-blockade during her pregnancy and exhibited no signs of tumor progression or symptoms throughout this period. Historically, higher rates of fetal and maternal morbidity and mortality have been experienced in the setting of pregnancy. Although limited data exist on the management of metastatic paraganglioma in pregnant patients, this case suggests that careful treatment modifications, such as temporary tyrosine kinase therapy cessation and vigilant monitoring, can result in successful pregnancies without compromising maternal or fetal well-being.

Learning points

• Paraganglioma in pregnancy has been associated with poor fetal and maternal morbidity and mortality.

• Many of the treatment modalities for metastatic paraganglioma, including tyrosine kinase inhibitors, can affect fertility or cannot be utilized in pregnancy, necessitating the temporary suspension of these treatments.

• This case exemplifies that careful clinical and biochemical monitoring during pregnancy is required to avoid maternal and fetal harm while balancing the risk of disease progression off treatment.

Summary

Congenital hyperinsulinism is the leading cause of persistent hypoglycaemia in infants and children; however, it is uncommon to be diagnosed in adulthood. We describe the cases of two sisters who presented with hyperinsulinaemic hypoglycaemia aged 47 and 57 years old, who were subsequently diagnosed with compound heterozygous likely pathogenic variants in the ABCC8 gene, a known cause of monogenic congenital hyperinsulinism. We discuss the typical presenting features, investigation findings, and treatment strategies for patients with this condition.

Learning Points

• Congenital hyperinsulinism is a rare cause of hyperinsulinaemic hypoglycaemia diagnosed in adulthood.

• Clinical presentation is similar to an insulinoma, and imaging modalities may assist in differentiation.

• There are minimal medical therapies currently available for patients non-responsive to diazoxide (such as those with ABCC8 and KCNJ11 variants).

• Continuous glucose monitoring can be helpful in giving patients autonomy in managing their disease, as well as relieving anxiety and fear associated with hypoglycaemia.