Ans. a. MPGN Type I MPGN is c.ommonly associated with persistent hepatitis C infections, autoimmune diseases like lupus or cryoglobulinemia, or neoplastic diseases."- Harrison 18/e p2344 So, in the above mentioned patient with Hepatitis C, exhibits hypo-complimentemia with 2 gm/day proteinuria and hematuria. The most probable diagnosis is MPGN Membranoproliferative Glomerulonephritis MPGN is sometimes called mesangiocapillary glomerulonephritis or lobar glomerulonephritis. It is an immune-mediated glomerulonephritis characterized by thickening of the GBM with mesangioproliferative changes; 70% of patients have hypocomplementemiaQ. MPGN is subdivided pathologically into type I, type II, and type III disease. Type I MPGN is commonly associated with persistent hepatitis C. infectionsQ, autoimmune diseases like lupus or cryoglobulinemiaQ, or neoplastic diseases Types II and HI MPGN are usually idiopathic`, except in patients with complement factor H deficiency, in presence of C3 nephritic factor and/or in paial lipodystrophy producing type II disease, or complement receptor deficiency in type III disease. Membranoproliferative Glomerulonephritis Type I MPGN (Most Common) Idiopathic SABEQ SLEQ Hepatitis CQ +- cryoglobulinemia Mixed cryoglobulinemia Hepatitis bQ Cancer: Lung, breast and ovary (germinal) Type li MPGN(Dense Deposit Disease) Idiopathic C3, nephritic factorassociatedQ Type Ill MPGN Idiopathic Complement receptor deficiencyQ