Association of secretory IgA with clinical pathological characteristics and complement activation in IgA nephropathy / 中华肾脏病杂志

ABSTRACT

Objective To further investigate the association among clinical pathology,complement activation and renal secretory IgA (SIgA) deposition in patients with IgA nephropathy (IgAN).Methods The activation of serum complements were detected by immunoturbidimetry and ELISA.Renal deposition of SIgA and activation of complements were detected by immunofluorescence.Then the association among clinical pathology,complement activation and renal SIgA deposition were analyzed in IgAN patients.Results In all 201 patients with IgAN,59 patients had SIgA deposition with higher incidences of mucosal infection history and hematuria (P ＜ 0.05),lower levels of serum cystatin C,β2 microglobulin and lower tubulointerstitial lesion grades and T-grade in the Oxford classification (P ＜ 0.05),when compared with patients without SIgA deposition.Both alternative and mannose binding lectin (MBL) pathways were activated in patients with or without SIgA deposition.Patients with MBL pathway activation had lower estimate glomerular filtration rate (P ＜ 0.01),higher serum creatinine,higher proportion of glomerulosclerosis and S-grade in the Oxford classification,more severe tubulointerstitial lesion (P ＜ 0.05).Conclusions Compared with patients without SIgA deposition,patients with SIgA deposition have a stronger link to mucosal immune.The deposition of SIgA is associated with different clinical and pathological manifestations;however,the complement activation is similar in both groups of patients.Patients with MBL pathway activation show more severe kidney injury.