Congenital Mesoblastic Nephroma Presenting With Hematuria in a Neonate: A Case Report.

Congenital mesoblastic nephroma (CMN) is the most frequent renal neoplasm of newborns and young infants. Four cases presenting with hemorrhagic manifestations have been reported in the English literature (Hu et al, 2006; Bolande et al, 1967). We report the unusual clinical and radiographic findings of a 2-day-old neonate with hematuria secondary to a CMN. The first ultrasound was equivocal. Repeat ultrasound followed by magnetic resonance imaging confirmed the diagnosis. He underwent a right nephroureterectomy with histopathology revealing a cellular variant of CMN without classical translocation (t12:15). Neonates presenting with hematuria require close follow-up and serial imaging to rule out occult renal tumors. Classical translocation may not be demonstrable in all the cases.