[Chronic lymphoid leukemia and renal complication: Report on 10 cases from Marseille over 16 years].

INTRODUCTION: Chronic lymphoid leukemia (CLL) is a hematological malignant disease, associated with a clonal B cell proliferation. The incidence is 4400 new cases per year in France. The prevalence increases with age with a median age at diagnostic of 65 years. Renal involvement is rare and estimated at 1.2% of patients with CLL. Renal pathological diagnoses associated with CLL are variable and are not always related to the hematological disease. We report here on cases of patients with CLL who underwent a renal biopsy over the past 16 years in Marseille.

METHODS: All cases of renal biopsies performed in patients with CLL between2000 and 2016 in Marseille were included. Pathological analysis was performed by the same experimented pathologist. Data were collected at the time of biopsy and after treatment.

RESULTS: Ten patients were included in this study. The reason for renal biopsy was acute kidney injury or the onset of nephrotic syndrome. We report on 4 cases of membranous nephropathy, 1 minimal change disease, 1 cryglobulinemia-related membrano-proliferative glomerulonephritis, 1 light chain amyloidosis, 1 fibrillary glomerulonephritis, 1 interstitial monoclonal infiltration and one case of non-specific tubular lesions. Only one patient was treated before the biopsy, 7 patients received a specific hematological treatment of CLL because of its renal involvement. Renal and hematological responses were variable.

CONCLUSION: Renal involvement of CLL is rare and is not mentioned in the Binet classification. Yet, it can be severe, with acute kidney injury or nephrotic syndrome, and can lead to the initiation of a specific treatment. The most frequent presentation this series was secondary MN, which differs from previous series.