Small Incidental Pheochromocytoma Presenting With Normal or Borderline High 24-hour Urine Fractionated Metanephrines.

A 73-year-old man was found to have a 2-cm lipid-poor right adrenal incidentaloma on computed tomography imaging for hematuria. Twenty-four-hour urine metanephrine was 1.1-fold elevated, then normal on repeat measurement. Paired with the second urine collection, plasma metanephrine measured by liquid chromatography tandem mass spectrometry after a 30-minute supine rest was 3.3-fold elevated. Plasma normetanephrine was 1.2-fold elevated. The 24-hour urine catecholamines and normetanephrine, measured twice, were normal. He received low-dose phenoxybenzamine and underwent successful resection of right pheochromocytoma. Postoperatively, both plasma metanephrine and normetanephrine levels normalized, using an age-appropriate upper reference limit for plasma normetanephrine. Patients who harbor small lipid-poor adrenal incidentalomas have a relatively high risk (>5%) of having pheochromocytoma, indistinguishable from adenomas or carcinomas on computed tomography scan. In such cases when 24-hour urine fractionated metanephrines are normal, plasma free metanephrines measured by liquid chromatography tandem mass spectrometry under optimal sampling conditions that are 2-fold or more elevated confirm the diagnosis of pheochromocytoma. Preoperative alpha blockade followed by surgical resection is then appropriate, rather than continued monitoring with repeat urine measurements.

Subclinical phaeochromocytoma: a diagnostic and management challenge.

There is a paradigm shift in the detection of phaeochromocytomas with more being identified as adrenal 'incidentalomas'. While majority of these individuals are asymptomatic, they are nevertheless at risk of subtle cardiovascular dysfunction and phaeochromocytoma crises. Therefore, early resection of phaeochromocytomas, even if subclinical, is recommended. However, the perioperative management can be challenging as the normotension can limit the initiation and titration of alpha-blockade. We present a man in his 60s with a subclinical phaeochromocytoma, discuss the evaluation of an incidentally discovered adrenal nodule, as well as the practical considerations in the perioperative management.

Severe Hypothyroxinemia in a Young Adult with Carbimazole-Treated T3-Predominant Graves' Hyperthyroidism, Reversed with L-Thyroxine Loading Immediately Post-Total Thyroidectomy.

Patients with triiodothyronine (T3)-predominant Graves' hyperthyroidism with markedly elevated serum thyroid stimulating immunoglobulin (TSI) levels and massive goitre may display discordant hypothyroxinemia with eutriiodothyroninemia or hypertriiodothyroninemia while on anti-thyroid drug therapy. A 25-year-old female with the above was started on oral carbimazole therapy for 9 months before total thyroidectomy. Preoperatively, her serum free T4 was reduced to below detection limit, and total T4 reduced to 11% of lower limit of normal, while T3 levels remained normal, and TSH remained largely suppressed. Immediately after total-thyroidectomy, a loading dose of L-thyroxine (L-T4) was administered intravenously. She was extubated without any postoperative complications. Serum free and total T4, and TSH normalized within the next 24 hours. The peculiar thyroid axis dynamics and use of L-T4 postoperative loading in such a rare clinical scenario are discussed.

Agoitrous Graves' Hyperthyroidism with Markedly Elevated Thyroid Stimulating Immunoglobulin Titre displaying Rapid Response to Carbimazole with Discordant Thyroid Function.

We characterize the clinical and laboratory characteristics of 5 patients with Graves' thyrotoxicosis whose serum free thyroxine (fT4) concentration decreased unexpectedly to low levels on conventional doses of carbimazole (CMZ) therapy. The initial fT4 mean was 40.0 pM, range 25-69 pM. Thyroid volume by ultrasound measured as mean 11 ml, range 9.0-15.6 ml. Initial TSI levels measured 1487% to >4444%. Serum fT4 fell to low-normal or hypothyroid levels within 3.6 to 9.3 weeks of initiating CMZ 5 to 15 mg daily, and subsequently modulated by fine dosage adjustments. In one patient, serum fT4 fluctuated in a "yo-yo" pattern. There also emerged a pattern of low normal/low serum fT4 levels associated with discordant low/mid normal serum TSH levels respectively, at normal serum fT3 levels. The long-term daily-averaged CMZ maintenance dose ranged from 0.7 mg to 3.2 mg. Patients with newly diagnosed Graves' hyperthyroidism who have small thyroid glands and markedly elevated TSI titres appear to be "ATD dose sensitive." Their TFT on ATD therapy may display a "central hypothyroid" pattern. We suggest finer CMZ dose titration at closer follow-up intervals to achieve biochemical euthyroidism.

Addisonian crisis and tuberculous epididymo-orchitis.

OBJECTIVE: To describe a case of acute primary adrenal insufficiency in which tuberculosis was subsequently detected as the etiologic factor when the patient presented with tuberculous epididymo-orchitis. METHODS: A case of acute primary adrenal insufficiency associated with bilaterally enlarged adrenal glands is reported, along with the subsequent finding of a scrotal mass diagnosed as tuberculous epididymo-orchitis. Diagnosis, adrenal function, and results of imaging studies after institution of antituberculous treatment are discussed. RESULTS: A 41-year-old Egyptian man, who had immigrated to the United States 5 years previously, had acute psychosis and addisonian crisis. A substantially increased early morning level of plasma adrenocorticotropic hormone and a low level of serum cortisol confirmed the diagnosis of primary adrenal insufficiency. Both adrenal glands were enlarged but without calcification on computed tomography. A previous bacille Calmette-Guérin vaccination complicated the interpretation of a positive tuberculin skin test result. Both lungs were clear on chest radiography and computed tomography. Seven months later, the patient had a left scrotal mass and underwent radical orchiectomy. Examination of the pathology specimen showed caseous granulomatous inflammation and necrosis, and acid-fast bacilli were identified. Culture was positive for Mycobacterium tuberculosis. CONCLUSION: In a patient from a country where tuberculosis is endemic, tuberculosis should be considered in the differential diagnosis when primary adrenal insufficiency is detected, especially in association with enlarged or calcified adrenal glands. Extra-adrenal tuberculous involvement should be actively sought because it may provide indirect microbiologic or histologic clues. Other than the lungs, special attention should be paid to the genitourinary system.