Membranoproliferative glomerulonephritis in association with chronic lymphocytic leukaemia: a report of three cases.

AIMS: The reported association of glomerular disease with chronic lymphocytic leukaemia (CLL) is rare despite the relative frequency of this type of leukaemia. Hence, we have examined the renal biopsies in three patients with CLL and glomerulonephritis. METHODS: Renal biopsies were examined by light microscopy, immunofluorescence microscopy and electron microscopy. RESULTS: One of two patients with mild impairment of renal function and an active urinary sediment had ultrastructural features of idiopathic type I membranoproliferative glomerulonephritis (MPGN), and the other had features of fibrillary/ immunotactoid glomerulonephritis with deposits of IgG and C3. One patient with nephrotic syndrome had characteristic electron microscopic appearances of type III MPGN. In all three there was an association with monoclonal gammopathy. The parameters of glomerular damage improved in association with response to drug treatment of the CLL. CONCLUSION: There is a spectrum of types of MPGN seen in patients with CLL and there appears to be an association with the presence of monoclonal gammopathy. This is the first reported case of type III MPGN in CLL.