New Classification Of 232 Cases Of Membranoproliferative Glomerulonephritis Based On Immunofluorescence Study

Objective:To investigate the new classification of membranoproliferative glomerulonephritis(MPGN).Methods:The clinical data of 232 patients diagnosed with membranoproliferative glomerulonephritis(MPGN)through renal biopsy from January 2011 to September 2016 were retrospectively analyzed.Inclusion criteria are as follows: 1.optical microscope showed MPGN,presented immune globulin(Ig)/immune complex(IC)and/or complement deposits on glomerulus under immunofluorescence.2.Age? 12 years;3.Exclusion of lupus nephritis.The data that needs to be observed included: gender,age,disease duration,clinical characteristics,laboratory examination as well as pathology data(optical microscope,immunopathogenesis,electron microscope,immunofluorescence staining).We intended to improve and make a classification on the basis of Mayo's classification.Results:A total of 232 MPGN were enrolled in the study,including 143 males and 89 females.The median age at renal biopsy was 57 years,the median Pro was 4.4 g / 24 h and the median creatinine was 1.32 mg / dl,of which 113(48.7%)had abnormal Scr(> 1.24 mg / dl).A total of 181 cases completedthe immunoelectrophoresis,of which 13 cases(7.18%)were positive for immunofluorescence,7 cases of K-Ig G,2 cases of?-Ig G,1 case of K-Ig A and 1 case of K-Ig M,1 case of K type,1 case of ?-Ig A type.42.16% of the blood light chain ?/? ratio was abnormal,with 52.59% and 8.19% of patients showing decreased complement C3 and complement C4 respectively.Thirty-five(15.1%)patients had C3 nephropathy and 197(84.9%)MPGN were deposited as immunocomplex(Igs ± C3).Among the 232 patients with MPGN,35(15.1%)were diagnosed with complementmediated MPGNand 197(84.9%)were diagnosed with immune complex-mediated MPGN.The former included 32 patientswith C3 Nephritis and 3 patientswith Dense deposit disease(DDD).The latter composed of 55 patientswith monoclonal deposits in the kidney which could be further divided in 44 patientswith Proliferative glomerulonephritis with monoclonal Ig deposits(PGNMID)and 11 patientswith Renal monoclonal immunoglobulin deposition disease(MIDD),and 142 patientswith polyclonal deposits including 52 infection-related cases(HBV/HCV)?4 autoimmune related cases ? 22 cases Cryoglobulinemic glomerulonephritis ? 1 case fibrillary glomerulonephritis and 63 cases Idiopathic.Only 10.3% patients with PGNMID had M-spike in serum while C3 glomerulonephritis holding 20.8%.The renal survival curve revealed that median survival time was 42 months,which significantly shorter than in the polyclonal group(P = 0.013).Conclusions:1)The new classification of MPGN based on immunofluorescence has practical value in revealing pathogenesis,finding cause and judging prognosis;2)Monoclonal immunoglobulinopathy and hepatitis virus infection were the first and second etiology of secondary MPGN in our country.