Interleukin-6 producing pheochromocytoma presenting with acute inflammatory syndrome.

Pheochromocytomas are tumors able to produce catecholamines and a variety of biologically active neuropeptides. We report the case of a 36-yr-old female patient with pheochromocytoma exhibiting headache, intermittent fever, thrombocytosis, and marked inflammatory signs. Nonsteroidal anti-inflammatory drugs were ineffective in lowering the body temperature, while a corticosteroid agent obtained excellent results. IL-6 was found elevated (20 pg/ml); it fell to 4.5 pg/ml 3 weeks after the adrenalectomy, in parallel to normalization of other laboratory data. The interleukin-6 (IL-6) over-production can either be ascribed directly to the tumor (as confirmed by immunohistochemistry) or indirectly accounted for by tumoral production, as a consequence of the high levels of circulating norepinephrine. To our knowledge, our paper represents the 6th case report of IL-6 secreting pheochromocytoma associated with clinical markers of inflammatory response.