Membranoproliferative Glomerulonephritis Secondary to a Low-Grade Lymphoproliferative Disorder: A Rare Cause of Renal Dysfunction.

Chronic lymphocytic leukemia is a B-cell neoplasm with an indolent clinical course. Most patients are asymptomatic and are diagnosed incidentally on a routine blood count. The malignant cells of this low-grade neoplasm infiltrate various organs and tissues. However, the resultant end organ damage is a rare phenomenon. Here we describe a case of chronic lymphocytic leukemia that presented with an unusual cause of acute renal dysfunction. The patient had deranged renal parameters with a nephrotic range proteinuria. The uncommon cause for his renal problem was membranoproliferative glomerulonephritis diagnosed by performing a kidney biopsy. Moreover, the acute renal dysfunction in this patient mandated an appropriate treatment and as of now there are no well-established treatment protocols for chronic lymphocytic leukemia with nephrotic syndrome. The patient was successfully treated with rituximab and bendamustine based on the expertise and judgement of the clinician.