Infected and ruptured retroperitoneal teratoma.

To cite: Shahizon AMM, Mohd Zaki F, Julian MR, et al. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/bcr-2013200862 DESCRIPTION We present images of an infected and ruptured retroperitoneal teratoma in an 8-month-old baby girl, who presented with a 2-week history of lowgrade intermittent fever and failure to thrive. On arrival at the hospital, she was lethargic, febrile and mildly dehydrated. The abdomen was distended with a palpable mass occupying the central abdomen and the left lumbar region. The white cell count and C reactive protein were elevated with measurement of 20.9 mg/dL and 6.27 mg/dL, respectively, indicating an underlying infection. Both tumour markers, α-fetoprotein (7.56 ng/mL) and β-human chorionic gonadotropin (<1.2 mlU/mL), were within normal limits. A sonographic study of the abdomen showed multiple intra-abdominal collections. The subsequent urgent abdominal CT revealed a relatively large left retroperitoneal cystic lesion with fatty and calcified components within (figure 1). The anterior wall of the lesion was disrupted and irregularly associated with multiple intraperitoneal collections. The overall appearances were compatible with a ruptured retroperitoneal teratoma. The patient underwent an emergency laparotomy with excision of the ruptured retroperitoneal tumour and drainage of the interloop intraperitoneal collections (figure 2). The final histopathological result confirmed that the mass was a benign mature teratoma. Retroperitoneal mature teratoma is a rare subgroup of teratoma. Tumour rupture and infection are known but rare complications of this tumour, which may result in significant morbidity if left untreated. Imaging plays an important role in the diagnosis of a mature retroperitoneal teratoma.