Pelvic Lipomatosis Causing Renal Failure

Observation A 34-year-old Cape Verdean male with terminal chronic renal failure of unknown etiology since two years was referred to the urology department for a second opinion after finding an infiltrative mass on routine renal ultrasound. The patient was nonobese and otherwise asymptomatic. Clinical examination revealed a large palpable mass in the pelvis. Laboratory examination showed highly elevated blood levels of creatinine (10.98 mg/dL (nl: 0.67– 1.17 mg/dL)) and urea (123 mg/dL (nl: 16.6–48.5 mg/dL)). We decided to perform a contrast-enhanced CT scan for further evaluation of the mass. The application of contrast agents in this patient with renal failure was permitted because these contrast agents were washed out by dialysis afterwards. The CT examination showed a large pelvic infiltration by fatty tissue with typical attenuation (–40 to –100 Hounsfield units) (Figure 1, arrows) and bilateral small kidneys with atrophy and hydroureteronephrosis. The fatty tissue caused extrinsic compression of the bladder (Figures 1, 2, and 3, white star) and rectum (Figure 2, black star) resulting in morphological deformity. The findings led to the diagnosis of pelvic lipomatosis with secondary chronic renal failure.