Abstract:

61yearold female was admitted to the hospital with proteinuria,microscopic hematuria,anemia,hypocomplementemia for 10 months.Serum test disclosed monoclonal IgGλ  band and elevated λ free light chain(λFLC).Ultrasonography showed bilateral kidney enlargement,bone marrow cytology disclosed 75% of plasmacyte with normal morphology.A kidney biopsy was carried out.On light microscopy,the main manifestation is membranoproliferative glomerulonephritis with nodular lesions,IF showed granular staining of IgG1(++) and λ light chain (+) in the mesagium and capoillary walls,while IgG2,IgG3,IgG4 and κ light chain were negative.The final diagnosis was proliferative glomerulonephritis with monoclonal IgG1 deposits,the patient was treated with thalidomide and dexamethasone for 1 year,On last follow up,the proteinuria and M protein disappeared,serum κ/λ ratio normalized,hypocomplementemia improved.

Key words: monoclonal gammapathy, membranoproliferative glomerulonephritis, thalidomide, dexamethasone