Clinicopathological Study in 55 Children with Primary Immunoglobulin A Nephropathy

Objective To explore the clinical manifestations,pathologic features,and prognosis of primary immunoglobulin A nephropathy(IgAN) in children.Methods The clinical manifestations and pathological findings of 55 children with primary IgAN were carefully studied and correlated.Thirty five boys and 20 girls aged from 2 to 16 years old were included in this study.They accounted for 10.5% in children undergoing renal biopsy in the same period.Results Nephrotic syndrome was the most common clinical manifestation(30.9%),followed by simple hematuria(25.5%),hematuria with proteinuria(23.6%),acute nephritic syndrome((18.2%)) and chronic nephritic syndrome(1.8%).Pathologically,grade Ⅲ was most frequent(61.8%),followed by grade Ⅳ((21.8%)),gradeⅡ(12.7%),and gradeⅠ(3.6%) was the least.The deposition of IgA+IgM+IgG(+C_3) in the glomeruli was most common(45.5%),followed by IgA+IgM(+C_3) deposition(30.9%),solo IgA deposition(21.8%) and full-house deposition((1.8%)).The severity of glomerular lesion significantly correlated with clinical manifestations through double trend analysis(χ~2=(6.012) P=0.014).Proteinuric patients showed more serious glomerular lesions than those with isolated hematuria.The immunofluorescence pattern also showed close relationship with clinical manifestation,as solo IgA deposition was most frequent in patients with isolated hematuria,while deposition of IgA+IgM+IgG(+C_3) was predominant in patients presented with nephrotic syndrome.Among 24 children followed-up for a mean duration of 39 months,only 1 isolated hematuric case still had hematuria,another cases,who originally presented with hematuria and proteinuria,showed that proteinuria attenuated but hematuria remained unchanged,other 22 patients remarkably ameliorated both in hematuria and proteinuria and only had a few erythrocytes and trace protein in urine.Conclusions The clinical characteristics of primary IgAN in children are somewhat correlated with pathological changes.The patients with nephrotic syndrome or nephritic syndrome are more likely to have serious pathological grades like grade Ⅲ and grade Ⅳ,while the glomerular lesions are slight in patients with isolated hematuria.