Abstract
BACKGROUND: Spontaneous perirenal hemorrhage (Wunderlich syndrome) in the fetus is a rare urinary system disease. Prenatal ultrasound diagnosis presents challenges due to the lack of specific clinical features. CASE PRESENTATION: A 27-year-old Chinese woman gravida 2 para 0 found her fetus with the left Wunderlich syndrome accompanying bilateral hydronephroses and bladder dysfunction with an early diagnosis through prenatal ultrasound and postnatal magnetic resonance imaging. After a timely emergency cesarean section, the infant was administrated antimicrobial prophylaxis and an indwelling catheter treatment. Ultrasound follow-up showed his urinary system gradually developed normally. CONCLUSION: A fetus with bilateral hydronephroses accompanying bladder dysfunction should be observed because of the risk of spontaneous renal rupture with hemorrhage formation. Ultrasound and magnetic resonance imaging play a vital role in the diagnosis and follow-up of Wunderlich syndrome. Early diagnosis facilitates better pregnancy planning and appropriate care of newborns.