Patient Demographics

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Maria Flynn Department of Medicine, University of Calgary, Alberta, Canada

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Christopher Noss Department of Anesthesiology, Perioperative, and Pain Medicine, University of Calgary, Alberta, Canada

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Robert Miller Department of Cardiac Sciences, University of Calgary, Alberta, Canada

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Corey Adams Department of Cardiac Sciences, University of Calgary, Alberta, Canada

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Dean Ruether Department of Medicine, University of Calgary, Alberta, Canada

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Denise Chan Department of Radiology, University of Calgary, Alberta, Canada

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Janice Pasieka Department of Surgery, University of Calgary, Alberta, Canada

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Kirstie Lithgow Department of Medicine, University of Calgary, Alberta, Canada

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Summary

Carcinoid heart disease is a rare complication of carcinoid syndrome, resulting in right-sided valvular heart disease and subsequent heart failure due to long-term exposure to vasoactive substances. The management of this condition is complex, often requiring surgical intervention. Current perioperative regimens entail the use of prophylactic somatostatin analogs to prevent carcinoid crisis; however, regimens vary widely among practitioners and evidence supporting their efficacy in this clinical setting is mixed. This case report describes the perioperative management of a 65-year-old man with carcinoid heart disease requiring tricuspid and pulmonary valve replacement surgery. As an adjunct to somatostatin analog therapy, the novel tyrosine hydroxylase inhibitor, telotristat, was initiated preoperatively. This combination resulted in normalization of preoperative urinary 5-HIAA levels. The patient successfully underwent tricuspid and pulmonic valve replacement without evidence of carcinoid crisis. This clinical case is the first published documenting the use of telotristat in the perioperative period in a patient with carcinoid syndrome and carcinoid heart disease and was associated with a good long-term outcome despite the high-risk nature of the case.

Learning points

  • Carcinoid crisis is a life-threatening complication of carcinoid syndrome, resulting in hemodynamic instability, bronchospasm, and arrhythmia.

  • Cardiac surgical patients with carcinoid syndrome present a unique challenge as they are subject to physiologic conditions and medications which can potentiate intraoperative carcinoid crisis.

  • Perioperative management of patients with carcinoid syndrome currently entails the use of prophylactic somatostatin analogs; however, these agents do not prevent carcinoid crisis in all cases.

  • Telotristat, a tryptophan hydroxylase inhibitor, shows promise as an adjunctive therapy to somatostatin analogs to reduce the risk of intraoperative carcinoid crisis.

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Valerie Lai Department of Medicine, University of Alberta, Edmonton, AB, Canada

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Mariam Shahidi Department of Medicine, University of Alberta, Edmonton, AB, Canada
Division of Endocrinology and Metabolism, University of Alberta, Edmonton, AB, Canada

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Alicia Chan Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada

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Shailly Jain-Ghai Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada

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Summary

3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) lyase deficiency is an inborn error of metabolism resulting in a lack of ketogenesis and leucine catabolism. Hallmarks of decompensation include hypoglycemia without ketosis (or hypoketosis), metabolic acidosis, and hyperammonemia. Management includes avoiding fasting and restricting dietary protein and fat. Conversely, type 2 diabetes mellitus (T2DM) requires carbohydrate restriction and/or anti-hyperglycemic agents; thus, managing these co-existing disorders is challenging. A 36-year-old male with HMG-CoA lyase deficiency and T2DM (Hemoglobin A1c (HbA1c): 7.9%) presented with confusion and shock. Blood work revealed metabolic acidosis, hyperammonemia, hyperglycemia, and hypoketosis. The patient was diagnosed with hyperosmolar non-ketotic hyperglycemia and hyperammonemia secondary to HMG-CoA lyase metabolic decompensation requiring intensive care unit admission. Hyperammonemia management was challenging because alternative calories with i.v. dextrose (due to hyperglycemia) and i.v. lipids (due to HMG-CoA lyase deficiency) could not be provided as usual. The patient was started on hemodialysis and i.v. insulin with marked improvement. Once stabilized, metformin and insulin were initiated. T2DM impaired cellular glucose uptake and produced a state similar to hypoglycemia, despite the patient being profoundly hyperglycemic, which led to metabolic decompensation of HMG-CoA lyase deficiency. Managing T2DM and HMG-CoA lyase deficiency warrants special considerations due to the potential for metabolic decompensation with both hyperglycemia and hypoglycemia.

Learning points

  • In a patient with 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) lyase deficiency and type 2 diabetes mellitus (T2DM), management principles include avoiding hypoglycemia to prevent metabolic decompensation, providing insulin for proper glucose utilization, and moderation of carbohydrate intake to prevent consequences of chronic hyperglycemia.

  • The development of insulin resistance in the form of T2DM in HMG-CoA lyase deficiency likely triggered a state similar to hypoglycemia, leading to cellular energy deficiency and subsequently metabolic decompensation.

  • It is important to avoid hypoglycemia in patients with HMG-CoA lyase deficiency and T2DM, as the risk of metabolic decompensation is increased due to the lack of ketogenesis in HMG-CoA lyase deficiency.

  • Selection of antidiabetic agents in this patient population requires careful consideration, and agents that have a higher risk of hypoglycemia should be avoided.

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Raad Alwithenani Department of Medicine, Division of Endocrinology and Metabolism, University of Toronto, Toronto, Ontario, Canada
College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Jeddah, Saudi Arabia
King Abdullah International Medical Research Center, Jeddah, Saudi Arabia
Department of Medicine, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Jeddah, Saudi Arabia

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Danielle M Andrade Department of Medicine, Division of Neurology, University of Toronto, Toronto, Ontario, Canada

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Lingxin Zhang Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada

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Karen E Gomez-Hernandez Department of Medicine, Division of Endocrinology and Metabolism, University of Toronto, Toronto, Ontario, Canada

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Summary

Myopathy caused by thyrotoxicosis is not uncommon. Skeletal muscles are commonly involved, but dysphagia is a rare manifestation of thyrotoxicosis. We aim to raise awareness of dysphagia caused by hyperthyroidism and review similar cases in the literature. We present a case of severe dysphagia caused by hyperthyroidism. We also summarize similar case reports in the literature. Our patient is a 77-year-old man who presented with thyrotoxicosis related to Graves’ disease (GD), dysphagia to both liquid and solid food, and weight loss. Further investigations revealed severe esophageal dysphagia and a high risk for aspiration. He required the placement of a G-tube for feeding. After 8 weeks of methimazole treatment, his thyroid function normalized and his dysphagia improved significantly, leading to the removal of the feeding G-tube. We summarize 19 case reports published in the literature of hyperthyroidism leading to dysphagia. Patients with thyrotoxicosis and dysphagia are at higher risk for aspiration pneumonia and thyroid storm. Based on previous case reports, on average, approximately 3 weeks of treatment with anti-thyroidal drugs and beta-blockers is needed before patients can eat normally. We report a case of dysphagia associated with GD, which is rare and needs prompt recognition to restore euthyroid status. Dysphagia generally resolved with normalization of thyroid function.

Learning points

  • Myopathy caused by thyrotoxicosis is not uncommon.

  • Skeletal muscles are commonly involved, but dysphagia is a rare manifestation of thyrotoxicosis.

  • Dysphagia due to hyperthyroidism resolves with normalization of thyroid function.

  • Early recognition of dysphagia related to hyperthyroidism and early initiation of therapy may help reverse the dysphagia and prevent complications.

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Alexandra Stephenson Department of Biochemistry and Molecular Biology & Arnie Charbonneau Cancer Institute, University of Calgary, Calgary, Alberta

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Zoya Punjwani Department of Medical Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta

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Markus Eszlinger Department of Oncology, Biochemistry and Molecular Biology, and Pathology and Laboratory Medicine, Cumming School of Medicine & Arnie Charbonneau Cancer Institute, University of Calgary, Calgary, Alberta

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Beata Sawicka Department of Pediatrics, Endocrinology, Diabetology with Cariology Division, Medical University, Bialystok, Poland

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Artur Bossowski Department of Pediatrics, Endocrinology, Diabetology with Cariology Division, Medical University, Bialystok, Poland

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Ralf Paschke Departments of Medicine, Oncology, Pathology and Laboratory Medicine, and Biochemistry and Molecular Biology & Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta

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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.

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Ahmad Housin Division of Endocrinology, Department of Medicine

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Marc P Pusztaszeri Department of Pathology, Jewish General Hospital, McGill University, Montreal, Quebec, Canada

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Michael Tamilia Division of Endocrinology, Department of Medicine

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Summary

Fever of unknown origin is a commonly encountered medical problem. Most common causes include infections, malignancy, and connective tissue diseases. Endocrine causes are rare but are well documented. While fever is common in some endocrine disorders, fever of unknown origin as the sole presenting feature is very rare. We describe a case report of a 63-year-old male who presents with fever of unknown origin. Imaging and biopsy results confirmed the diagnosis of subacute thyroiditis. He was started on prednisone with a good response. We conclude that subacute thyroiditis should be considered in the work up of fever of unknown origin even in the absence of classical signs and symptoms.

Learning points:

  • Fever of unknown origin is a rare sole presentation of subacute thyroiditis.

  • The classic signs and symptoms may not be manifest at the time of presentation.

  • Normal thyroid function tests and elevated markers of inflammation often make infections, malignancy and autoinflammatory conditions the prime consideration.

  • Imaging of the thyroid gland may point to a morphologic aberration and prompt a thyroid biopsy.

  • After exclusion of infection, a rapid response to steroids may be both diagnostic and therapeutic.

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S Hamidi Division of Endocrinology, Department of Medicine, Hôpital Maisonneuve-Rosemont, Montréal, Canada

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S Mottard Division of Orthopedic Surgery, Department of Surgery, Hôpital Maisonneuve-Rosemont, Montréal, Canada

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M J Berthiaume Department of Radiology, Hôpital Maisonneuve-Rosemont, Montréal, Canada

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J Doyon Department of Pathology, Hôpital Maisonneuve-Rosemont, Montréal, Canada

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M J Bégin Division of Endocrinology, Department of Medicine, Hôpital Maisonneuve-Rosemont, Montréal, Canada

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L Bondaz Division of Endocrinology, Department of Medicine, Hôpital Maisonneuve-Rosemont, Montréal, Canada

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Summary

Brown tumors (BTs) are expansile osteolytic lesions complicating severe primary hyperparathyroidism (PHPT). Clinical, radiological and histological features of BTs share many similarities with other giant cell-containing lesions of the bone, which can make their diagnosis challenging. We report the case of a 32-year-old man in whom an aggressive osteolytic lesion of the iliac crest was initially diagnosed as a giant cell tumor by biopsy. The patient was scheduled for surgical curettage, with a course of neoadjuvant denosumab. Routine biochemical workup prior to denosumab administration incidentally revealed high serum calcium levels. The patient was diagnosed with PHPT and a parathyroid adenoma was identified. In light of these findings, histological slices of the iliac lesion were reviewed and diagnosis of a BT was confirmed. Follow-up CT-scans performed 2 and 7 months after parathyroidectomy showed regression and re-ossification of the bone lesion. The aim of this case report is to underline the importance of distinguishing BTs from other giant cell-containing lesions of the bone and to highlight the relevance of measuring serum calcium as part of the initial evaluation of osteolytic bone lesions. This can have a major impact on patients’ management and can prevent unnecessary invasive surgical interventions.

Learning points:

  • Although rare, brown tumors should always be considered in the differential diagnosis of osteolytic giant cell-containing bone lesions.

  • Among giant cell-containing lesions of the bone, the main differential diagnoses of brown tumors are giant cell tumors and aneurysmal bone cysts.

  • Clinical, radiological and histological characteristics can be non-discriminating between brown tumors and giant cell tumors. One of the best ways to distinguish these two diagnoses appears to be through biochemical workup.

  • Differentiating brown tumors from giant cell tumors and aneurysmal bone cysts is crucial in order to ensure better patient care and prevent unnecessary morbid surgical interventions.

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Catherine Alguire Division of Endocrinology, Department of Medicine and Research Center (CRCHUM), Centre hospitalier de l’Université de Montréal, Montreal, Québec, Canada

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Jessica Chbat Division of Endocrinology, Department of Medicine and Research Center (CRCHUM), Centre hospitalier de l’Université de Montréal, Montreal, Québec, Canada

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Isabelle Forest Department of Psychiatry, Centre hospitalier Pierre-Le Gardeur, Terrebonne, Québec, Canada

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Ariane Godbout Division of Endocrinology, Department of Medicine and Research Center (CRCHUM), Centre hospitalier de l’Université de Montréal, Montreal, Québec, Canada

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Isabelle Bourdeau Division of Endocrinology, Department of Medicine and Research Center (CRCHUM), Centre hospitalier de l’Université de Montréal, Montreal, Québec, Canada

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Summary

Pheochromocytoma is a rare tumor of the adrenal gland. It often presents with the classic triad of headache, palpitations and generalized sweating. Although not described as a typical symptom of pheochromocytoma, anxiety is the fourth most common symptom reported by patients suffering of pheochromocytoma. We report the case of a 64 year old man who had severe anxiety and panic disorder as presenting symptoms of pheochromocytoma. After 13 years of psychiatric follow-up, the patient was diagnosed with malignant pheochromocytoma. After surgical resection of his pheochromocytoma and his hepatic metastases, the major panic attacks completely disappeared, the anxiety symptoms improved significantly and the psychiatric medications were stopped except for a very low maintenance dose of venlafaxine. We found in our cohort of 160 patients with pheochromocytoma 2 others cases of apparently benign tumors with severe anxiety that resolved after pheochromocytoma resection. These cases highlight that pheochromocytoma should be included in the differential diagnosis of refractory anxiety disorder.

Learning points:

  • Anxiety and panic disorder may be the main presenting symptoms of pheochromocytoma.

  • The diagnosis of pheochromocytoma should be excluded in cases of long-term panic disorder refractory to medications since the anxiety may be secondary to a catecholamine-secreting tumor.

  • Surgical treatment of pheochromocytoma leads to significant improvement of anxiety disorders.

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Syed Ali Imran Division of Endocrinology and Metabolism, Dalhousie University, Halifax, Nova Scotia, Canada

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Khaled A Aldahmani Division of Endocrinology, Tawam Hospial, Al-Ain, UAE

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Lynette Penney Department of Pediatrics, Tawam Hospial, Al-Ain, UAE

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Sidney E Croul Department of Pathology, Tawam Hospial, Al-Ain, UAE

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David B Clarke Department of Neurosurgery, Dalhousie University, Halifax, Nova Scotia, Canada

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David M Collier Centre for Endocrinology, Barts and the London School of Medicine, Queen Mary University of London, London, UK

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Donato Iacovazzo Centre for Endocrinology, Barts and the London School of Medicine, Queen Mary University of London, London, UK

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Márta Korbonits Centre for Endocrinology, Barts and the London School of Medicine, Queen Mary University of London, London, UK

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Summary

Early-onset acromegaly causing gigantism is often associated with aryl-hydrocarbon-interacting receptor protein (AIP) mutation, especially if there is a positive family history. A15y male presented with tiredness and visual problems. He was 201 cm tall with a span of 217 cm. He had typical facial features of acromegaly, elevated IGF-1, secondary hypogonadism and a large macroadenoma. His paternal aunt had a history of acromegaly presenting at the age of 35 years. Following transsphenoidal surgery, his IGF-1 normalized and clinical symptoms improved. He was found to have a novel AIP mutation destroying the stop codon c.991T>C; p.*331R. Unexpectedly, his father and paternal aunt were negative for this mutation while his mother and older sister were unaffected carriers, suggesting that his aunt represents a phenocopy.

Learning points:

  • Typical presentation for a patient with AIP mutation with excess growth and eunuchoid proportions.

  • Unusual, previously not described AIP variant with loss of the stop codon.

  • Phenocopy may occur in families with a disease-causing germline mutation.

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Xin Feng Division of Endocrinology, Department of Medicine, University of Calgary, Calgary, Alberta,Canada

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Gregory Kline Division of Endocrinology, Department of Medicine, University of Calgary, Calgary, Alberta,Canada

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Summary

In a 61-year-old Caucasian male with prostate cancer, leuprolide and bicalutamide failed to suppress the androgens. He presented to endocrinology with persistently normal testosterone and incidental massive (up to 18 cm) bilateral adrenal myelolipomas on CT scan. Blood test did not reveal metanephrine excess. The patient was noted to have short stature (151 cm) and primary infertility. Elementary school photographs demonstrated precocious puberty. Physical examination revealed palpable abdominal (adrenal) masses. Abiraterone and glucocorticoid treatment was commenced with excellent suppression of testosterone. Genetic testing revealed a mutation in CYP21A2 confirming 21-hydroxylase-deficient congenital adrenal hyperplasia (CAH). Association of large myelolipomas with CAH has been reported in the literature. Our case highlights the importance of considering CAH in patients with non-suppressed testosterone despite androgen deprivation therapy. Large myelolipomas should raise the suspicion of congenital adrenal hyperplasia.

Learning points:

  • Adrenal myelolipomas are rare benign lesions that are more common in patients with longstanding untreated congenital adrenal hyperplasia thought to be due to ACTH stimulation.

  • Consider undiagnosed congenital adrenal hyperplasia in patients with adrenal myelolipoma.

  • Glucocorticoid replacement may be an efficacious treatment for patients with prostate cancer and CAH. Abiraterone therapy has a risk of adrenal crisis if glucocorticoids are not replaced.

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Gerald J M Tevaarwerk University of Western Ontario, London, Ontario N6A 5C1, Canada

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Summary

Low triiodothyronine (T3) concentrations in the presence of normal thyroxine (T4) and TSH levels, referred to as the low T3 syndrome (LT3S), are common. LT3S may be caused by starvation, various non-thyroidal illnesses (NTIs) and some medications. Reverse T3 (rT3) concentrations are elevated in the more severely ill, and they characteristically fail to respond to exogenous levothyroxine (l-T4) therapy. The biochemical abnormalities have been explained on the basis of altered peripheral deiodinase activities. Herein, we report on two patients with hypothyroid symptoms who on testing were found to have LT3S. They were atypical clinically in not having LT3S due to any of the usual causes, had no increased rT3 concentrations, and had a normal negative TSH feedback response to l-T4. One (patient 1) had previously been diagnosed with Hashimoto's autoimmune primary hypothyroidism and was on l-T4 therapy. Both had T4 concentrations in the reference range. TSH levels were elevated in patient 1 and in the reference range in patient 2. Starting or increasing l-T4 doses resulted in no clinical improvement and no increase in T3 levels in spite of a marked increase in T4 levels. It is suggested that in the absence of the usual causes, lack of elevated rT3 levels, response to treatment and intact negative TSH feedback these two patients differ from the usual secondary causes of decreases in deiodinase activity. It is speculated that they may represent primary alterations in deiodinase enzymes possibly due to genetic variations in the deiodinase-encoding genes.

Learning points

  • LT3S is commonly found secondary to starvation, NTIs and use of some medications.

  • Low T3 levels are the result of alterations in the activity of deiodinase enzymes.

  • LT3S without the usual causes may represent a primary disturbance in deiodinase activity.

Open access