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

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

Thyroid storm is a clinical diagnosis characterized by life-threatening multisystemic organ involvement in the setting of uncontrolled hyperthyroidism. Current estimates suggest a mortality rate of up to 30%. Treatment often consists of the administration of thionamide medications, iodine solution(s), corticosteroids, and beta-blockers; in extreme circumstances, both plasmapheresis and thyroidectomy are subsequent therapeutic options. Thionamides are typically administered orally, with the intent of preventing further thyroid hormone synthesis; however, in the literature, there are instances whereby oral access cannot be obtained, and alternative routes of administration are required. We present a case of a patient who presented with a thyroid storm due to lack of adherence to methimazole. During admission, he was found to have significant abdominal pain and ultimately a duodenal perforation requiring strict nil-per-os (NPO) status, due to which he was unable to receive oral thionamides. Due to the lack of availability of intravenous formulations of thionamides in the United States, this patient was treated with an enema compound of propylthiouracil for a total of five per rectum (PR) doses. He would later develop hepatocellular injury, requiring discontinuation and eventual transition to oral methimazole. The literature pertaining to alternative-route thionamide administration is scant, and therefore this case report and literature review is written to provide an up-to-date review and further educate all levels of clinicians about this infrequent (but emergent) situation.

Learning points

• Thyroid storm is a clinical diagnosis for which urgent recognition is required to prevent untoward mortality.

• Treatment for thyroid storm requires prompt administration of thionamides, iodine, corticosteroids, and beta-blockers. In extreme circumstances, treatment considerations include plasmapheresis and thyroidectomy.

• Infrequently, patients with a thyroid storm may not be able to tolerate oral medications, for which alternative routes of access are required.

• Currently, available alternatives include intravenous methimazole (in Europe and Japan), as well as both enema and suppository preparations of propylthiouracil and methimazole.

Summary

Moyamoya syndrome (MMS) refers to a rare cerebrovascular disorder characterized by progressive stenosis of the intracranial internal carotid arteries and their proximal branches, leading to an increased risk of stroke. While prevalent in Asia, this condition is considerably less common in Western countries, including Europe. The association between MMS and Graves’ disease (GD) has been well documented, primarily in Asian and American populations, notably Latin Americans. In this report, we report the first case of GD with MMS in a Caucasian woman from Western Europe. The precise mechanisms underpinning the correlation between these two conditions remain poorly elucidated but are hypothesized to involve hemodynamic alterations, the toxic effects of anti-thyroid-stimulating hormone receptor antibodies, or a shared genetic predisposition. Our clinical case underscores the significance of thyroid disease screening in suspected MMS cases, as the management of thyroid dysfunction may suffice to improve neurological symptoms.

Learning points

• The association between Graves’ disease (GD) and Moyamoya syndrome (MMS) can manifest in a Caucasian European patient.

• Screening for thyroid disease is essential when MMS is suspected, as treating GD might effectively alleviate neurological symptoms.

• The mechanisms linking GD and MMS remain incompletely understood but may involve hemodynamic shifts, the toxic effect of anti-TSH receptor antibodies, or shared genetic factors.

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

The resistance to thyroid hormone syndrome (RTHβ) occurs uncommonly and requires a high level of clinical suspicion and specific investigations to reach a precise diagnosis and to avoid unnecessary and potentially harmful therapies. We report a case of a young male patient referred to our unit for SARS-CoV-2 infection and atrial fibrillation with elevated thyroid hormones and non-suppressed thyroid-stimulating hormone (TSH), for which antithyroid therapy was prescribed. A mood disorder was reported in the medical history. The family history was unknown as the patient was adopted. Thyroid-specific antibodies were undetectable, and thyroid ultrasound revealed a normal thyroid gland without nodules. After the resolution of SARS-CoV-2 infection, the diagnostic workup continued, and the pituitary MRI revealed a small area ascribable to a microadenoma. Due to atrial fibrillation, the execution of the T3 test was contraindicated. The octreotide long-acting release (LAR) test showed an initial reduction of free thyroid hormones levels at first administration, which was consistent with the presence of a TSH-secreting pituitary tumour, although an escape from the response was observed after the following two injections of octreotide LAR. Indeed, the genetic investigation revealed a variant in heterozygosity of the THRβ gene (Pro453Ser), thus leading to an RTHβ diagnosis, and, therefore, medical treatment with triiodothyroacetic acid was initiated. After 2 years from the SARS-CoV-2 infection, the patient continues the follow-up at our outpatient clinic, and no other medical interventions are needed.

Learning points

• RTHβ is a rare genetic syndrome characterised by discrepant thyroid function tests and by a dissociation between the observed hormone levels and the expected patient signs and symptoms.

• Features of thyroid hormone deficiency in TR-ß dependent tissues (pituitary gland, hypothalamus, liver and neurosensitive epithelia), as well as thyroid hormone excess in TR-α-dependent tissues (heart, bone, skeletal muscle and brain), may coexist in the same individual.

• Clinical pictures can be different even when the same variant occurs, suggesting that other genetic and/or epigenetic factors may play a role in determining the patient’s phenotype.

• Differentiating RTHβ from a TSH-secreting pituitary tumour is very difficult, especially when a concomitant pituitary adenoma is detected during diagnostic workup. The injection of long-acting somatostatin analogues can help differentiate the two conditions, but it is important to detect any interference in the dosage of thyroid hormones to avoid an incorrect diagnosis.

• Genetic testing is fundamental to prevent unnecessary and potentially harmful therapies.

• Medical treatment with triiodothyroacetic acid was demonstrated to be effective in reducing thyroid hormone excess and controlling symptoms.

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.