Retroperitoneal teratoma presenting as an abscess in childhood.

Retroperitoneal teratomas are rare, representing only 1% to 11% of primary retroperitoneal neoplasms. They typically present as an asymptomatic abdominal mass but can grow to enormous size. This case describes a patient who initially presented in childhood with an acute abdomen because of an abdominal abscess that was treated with surgical drainage and antibiotics. Fifteen years later, the patient had a recurrence of symptoms and the abscess was ultimately recognized to be an infected retroperitoneal teratoma. There have been reports of intraabdominal and pelvic teratomas presenting as abscesses in adults. However, to our knowledge, there has been no prior description of this phenomenon in children. In an otherwise healthy child who presents with an unexplained abscess in the sacrococcygeal area, gonads, mediastinum, or retroperitoneum, one should entertain the diagnosis of teratoma.