SUCCESSFUL TREATMENT OF IGA NEPHROPATHY IN ASSOCIATION WITH LOW-GRADEB-CELL LYMPHOMA OF THE MUCOSA-ASSOCIATED LYMPHOID-TISSUE TYPE

Kidney and the urogenital tract are among the various mucosal sites in volved in mucosa-associated lymphoid tissue (MALT) lymphoma, We report a case with simultaneous onset of crescentic immunoglobulin (Ig) A ne phropathy and gastrointestinal low-grade B-cell lymphoma of the MALT t ype with kidney infiltration, M-component of IgM lambda was detected i n the serum, and the renal biopsy specimen showed monotypic lambda lig ht chain staining in the lymphoma cells but not the glomeruli, The hea vy proteinuria and impaired creatinine clearance returned to normal, a nd microscopic hematuria disappeared 20 months after treatment with ch lorambucil as single-agent chemotherapy, This coincided with a complet e resolution of the gastric and renal lymphoma infiltration, The close association of both the onset and successful outcome of the two entit ies thus support their possible causal relationship, and we discuss th e possibility of an association of the disturbance of the MALT by the lymphoma cells with the pathogenesis of IgA nephropathy. (C) 1998 by t he National Kidney Foundation, Inc.