Wilms Tumor Mimicking Renal Pelvis Hematoma in a Post-Traumatic Pediatric Patient: Case Report

Wilms’ tumor (WT) is the most common renal tumor of childhood. Children with WT may present with a large, painless, abdominal mass and usually no constitutional symptoms. In our case, there were neither symptoms nor any physical examination findings that would lead us to WT. Herein, we report a 4-year-old male who presented to our clinic with concern for a traumatic lesion in abdomen. He was asymptomatic and had a small bruise on left upper quadrant. Ultrasound revealed a heterogeneous lesion which fills the renal pelvis. Renal pelvis hematoma and space-occupying lesions originating from the collecting system epithelium was considered as differential diagnoses. After kidney biopsy, the diagnosis of WT was confirmed. We present this case of WT to keep it in mind in the differential diagnosis of renal pelvis hematoma in a pediatric post-traumatic patient. We emphasise the impor-tance of using multimodal approaches to make the correct diagnosis.