Biochemical and serological characteristics of children with membranous nephropathy due to hepatitis B virus infection: correlation with hepatitis B e antigen, hepatitis B DNA and hepatitis D

Fourteen children with biopsy-proven membranous nephropathy associated with hepatitis B virus (HBV-MN) were evaluated biochemically and serologically and compared to 45 children with idiopathic nephrotic syndrome (INS). The mean ages of the two groups were similar (4.9 +/- 1.6 vs. 4.6 +/- 2.6 years). Serum albumin levels were similar in both groups, but serum cholesterol was significantly reduced in children with HBV-MN compared to INS. Serum C3 was also significantly depressed in children with HBV-MN compared to INS, but no differences in C4 levels were noted. Serum alanine transaminase as well as aspartate transaminase concentrations were significantly elevated in children with HBV-MN compared to those with INS, suggesting the presence of chronic hepatitis in children with HBV-MN. Hepatitis B surface and e antigens were present in serum of all children with HBV-MN, but only 54% had circulating HBV-DNA particles demonstrable in their serum. Serum C3 levels were higher in children with HBV-MN and circulating HBV-DNA, compared to those without circulating HBV-DNA. No other serological or biochemical differences occurred between these two groups. Glomerular deposition of IgG and C3 occurred in 91% of children with HBV-MN; but IgM deposition appeared to occur more frequently and with greater intensity in those children positive for circulating HBV-DNA. Antibody to delta antigen was negative in all children with HBV-MN. We conclude that biochemical and serological differences can be identified between HBV-MN and INS.(ABSTRACT TRUNCATED AT 250 WORDS)