Wünderlich Syndrome Without Classic Signs: A Case of Spontaneous Retroperitoneal Hemorrhage From a Ruptured Renal Angiomyolipoma.

Wünderlich syndrome is a non-traumatic retroperitoneal hemorrhage confined to the subcapsular, perirenal, and/or pararenal space. It has been previously associated with Lenk's triad of flank pain, hematuria, and hypovolemic shock; however, this triad is not always present, making early recognition in the emergency department challenging. We describe a 39-year-old male who presented with sudden-onset severe left flank pain, diaphoresis, and persistent tachycardia without hematuria or hypotension. Contrast-enhanced computed tomography of the abdomen and pelvis rapidly showed a left renal angiomyolipoma with fat and extensive active retroperitoneal hemorrhage. Definitive care required interfacility transfer for angiography and transcatheter arterial embolization, during which active extravasation was identified from adrenal arterial branches. Despite aggressive resuscitative and endovascular measures, the patient experienced progressive hemodynamic deterioration and expired. This case reinforces that early cross-sectional imaging is essential for diagnosing spontaneous retroperitoneal hemorrhage, enabling timely escalation to interventional management. Prompt recognition, rapid imaging, and expedited access to definitive intervention remain critical determinants of outcome.