Fever of unknown origin (FUO) can be an unusual first clinical manifestation of pheochromocytoma. Pheochromocytomas are tumors that may produce a variety of substances in addition to catecholamines. To date, several cases of IL-6-producing pheochromocytomas have been reported. This report describes a 45-year-old woman with pheochromocytoma who was admitted with FUO, normal blood pressure levels, microcytic and hypochromic anemia, thrombocytosis, hyperfibrinogenemia, hypoalbuminemia, and normal levels of urine and plasma metanephrines. After adrenalectomy, fever and all inflammatory findings disappeared.

Background: Aorto-pulmonary window is a rare heart disease occurring in 0.1-0.2% of patients with congenital cardiac disease and results from an incomplete development of the conotruncal septum. In half of the cases aorto-pulmonary windows are associated with other anomalies. This condition can occur on its own or with other heart defects such as: tetralogy of fallot, pulmonary atresia, atrial septal defect, interrupted aortic arch, truncus arteriosus, patent ductus arteriosus. Fifty percent of patients usually have no other heart defects. Babies that have a hole in between the aorta and pulmonary artery have blood from the aorta that flows into the pulmonary artery, and as a result too much blood flows to the lungs. This causes high blood pressure in the lungs (a condition called pulmonary hypertension) and congestive heart failure. Symptoms can include: delayed growth, irritability, rapid heartbeat, heart failure, infections of the lungs. Case: We describe a case of aortopulmonary window incidentally found during surgery for a Type A interrupted aortic arch and repaired uneventfully. Conclusions: In our case the anomaly was not diagnosed until the thoracotomy but anatomy allowed surgeon to perform the closure of the window.