Ultrastructural Diagnosis of a Pheochromocytoma at Autopsy

Abstract Pheochromocytoma is a rare tumor found in approximately 2 individuals per million of the population. In 90% of cases, it arises from the chromaffin cells of the adrenal medulla. These cells secrete catecholamines: epinephrine and norepinephrine which have a sympathomimetic action. The classical clinical presentation is paroxysms of extreme elevation of systemic blood pressure. Although pheochromocytoma accounts for only 0.1 % of cases of systemic hypertension, it is important to make the diagnosis, as the sudden release of large quantities of catecholamines into the circulation may prove fatal, as happened in our patient. We present a case of a 25 year old woman, who collapsed suddenly, while she was feeding her 8 month old baby. She went into ventricular fibrillation and was defibrillated 3 times. There was no response to vigorous resuscitative measures. Past Medical History: No definitive findings. Vague history of palpitations and an “abnormal heart beat”, which had been considered to be benign.