QUIZ: No. 28, 27/09/2025

QUIZ No. 28

ANS – Left Wunderlich syndrome with pseudoaneurysm due to angiomyolipoma rupture

Findings – A heterogeneous endo-exophytic lesion with soft tissue and macroscopic fatty component and abnormal vascularity is seen in the lower pole of left kidney, compatible with a large angiomyolipoma. Variable density left perirenal fluid collection consistent with perirenal hematoma. After contrast media injection, the lesion shows heterogeneous enhancement with a 23 mm contrast-filled space within, inferring a pseudoaneurysm.

Wunderlich syndrome (WS) is a rare condition in which spontaneous non-traumatic renal haemorrhage occurs into the subcapsular and perirenal spaces.

Kidney neoplasms are responsible for 2/3 of all cases of WS, with angiomyolipoma as the most common benign tumour and RCC as the most common renal malignancy that predisposes patients to WS.

Lenk's triad - acute flank pain, flank mass and hypovolemic shock.

Risk factors for hemorrhage: lesion size > 4 cm, intralesional aneurysm > 5 mm and pregnancy.

Multiphasic CT and MRI are the mainstays of diagnosis, permitting the detection of the cause of spontaneous hemorrhage and providing the road map for interventional radiology or emergency surgery.

In hemodynamically stable patients, selective angiographic embolization may be pursued, whereas in unstable patients, emergent nephrectomy (partial or total) is often required

Take home point

Multiphasic CT and MRI: Gold standard for detecting hematoma, identifying the cause, and planning management (embolisation vs. surgery).