Gabriel Dickstein

Low-Dose ACTH Stimulation Test

Most symptoms and signs of adrenal insufficiency are nonspecific yet common. Because the disorder is life threatening but very easy to treat, it is essential that it be accurately diagnosed. A test that is simple, inexpensive, and accurate is needed for this purpose. The tests available in the past

Low-dose and high-dose adrenocorticotropin testing: indications and shortcomings.

Purpose of reviewThe 250 μg adrenocorticotropin test (high-dose test) is the most commonly used adrenal stimulation test, though the use of physiologic doses (1.0 μg or 0.5 μg/1.73 m2) (low-dose test) has recently gained wider acceptance. These variants and the use of adrenocorticotropin test in the ICU, however, remain controversial. The validity of the low-dose test and the parameters for evaluation of high- and low-dose tests in different situations need reevaluation. Recent findingsIn the last few years, numerous studies have used the low-dose test as a single test following previous findings that it is more sensitive and accurate than the high-dose test. It is used mainly in secondary adrenal insufficiency and after treatment with therapeutic glucocorticosteroids to define hypothalamo-pituitary-adrenal suppression. Unless there is a very recent onset of disease, the results are interpreted by most researchers as diagnostic. The treatment of relative adrenal insufficiency, based on delta cortisol, has not yielded proof of correlation between this diagnosis and better prognosis with glucocorticoid treatment. SummaryFor interpretation of an adrenocorticotropin test, only peak – and not delta – cortisol should be used. The use of 240–300 mg of hydrocortisone daily in ICU patients, including septic shock, should be considered as pharmacologic, rather than as a replacement dose. Using the low-dose test for this purpose will lead to further misdiagnosis.

Adrenalectomy for adrenocortical adenoma causing Cushing's syndrome in pregnancy: a case report and review of literature

We present a case of adrenocorticotropic hormone (ACTH)-independent Cushings syndrome diagnosed in a patient in the third trimester of her pregnancy, with an adrenal mass observed on imaging studies. Laparoscopic adrenalectomy was performed successfully at 32 weeks. To the best of our knowledge, this is the latest gestational age at which laparoscopic adrenalectomy has been reported. We present the various considerations for determining the surgical approach and the optimal timing for surgery. Adrenalectomy during pregnancy for the treatment of Cushings syndrome caused by adrenocortical adenoma has been reported in 23 patients in the English-language medical literature to date and seems safe and beneficial. According to the data, surgical treatment has led to a reduction in perinatal mortality and maternal morbidity rates, but has not affected the occurrence of preterm birth and intrauterine growth restriction. The best outcome can be achieved by a multidisciplinary approach, with a team comprising a maternal-fetal medicine specialist, an endocrinologist and a surgeon. The timing of surgery and the surgical approach need to be determined according to the surgeons expertise, the severity of the condition, the patients preferences, and gestational age. Laparoscopy may prove to be the preferred surgical approach. The small number of cases precludes providing evidence-based recommendations.

Thyrotoxicosis Induced by Amiodarone, a New Efficient Antiarrhythmic Drug With High Iodine Content

Amiodarone is an antiarrhythmic agent with high iodine content. Ten patients treated with amiodarone developed thyrotoxicosis. I131 uptakes were negligible, and TT3 levels low in relation to TT4 levels, and sometimes even normal.Cessation of amiodarone caused thyroid functions to return to normal in one to five months, unrelated to propylthiouracil treatment. Eight of the patients had normal thyroid glands on radioscan or palpation. All patients tested had normal TRH tests.Thyrotoxicosis is a relatively common complication of amiodarone treatment, probably caused by its high iodine content. It is possible in apparently normal thyroid glands, suggesting failure of the homeostatic mechanisms controlling thyroid synthesis and release in these patients.Amiodarone is very efficient in controlling tachyarrhythmias and angina pectoris, situations in which thyrotoxicosis is dangerous. Thyroid function tests should therefore be drawn periodically, and the complication considered whenever tachyarrhythmias worsen on treatment with amiodarone.