In pediatric trauma, inability to void with perineal bruising raises concern for urethral injury or urinary retention due to soft tissue swelling. The most immediate step is to attempt bladder catheterization. If unsuccessful, consult gynecology or urology urgently to avoid bladder overdistension.

Toronto Notes 2023 – Pediatrics, Genitourinary Trauma:

“In females, perineal trauma can lead to urinary retention due to labial hematomas or urethral injury. If catheterization is difficult, consult gynecology or urology for assistance.”

MCCQE1 Objectives – Pediatrics > Trauma and Emergency Care:

“Candidates must recognize when specialist consultation is required in pediatric genitourinary trauma, especially in cases of failed catheterization.”

Options B and D delay necessary care. Coagulation studies (C) may be considered if bleeding is unexplained. Abuse assessment (E) may be necessary later but does not address immediate retention.