Neonatal sacrococcygeal teratoma with acute renal failure.

Teratomas are germ cell tumours composed of multiple types of cells derived from more than a single germ cell layer. The most common site of an extragonadal teratoma is the sacrococcygeal region. We report a case of a 16-day-old female child with a large swelling in the sacrococcygeal region extending laterally into the buttocks with severely deranged renal functions. Ultrasonography and CT helped in making the diagnosis and, more importantly, to delineate the extent of the tumour and the involvement of adjacent organs and tissues: in our case, lower bilateral ureters. Imaging findings and clinical presentation led to the diagnosis of sacrococcygeal teratoma with renal failure.