Risk factors analysis of prognosis of microalbuminuria IgA nephropathy patients with decreased ;serum C3 level / 中国医师进修杂志

ABSTRACT

Objective To analyze the clinical and pathological data and prognosis of microalbuminuria IgA nephrology patients with decreased serum C3 level, and investigate the significance of decreased serum C3 level in microalbuminuria IgA nephrology patients. Methods Clinical and pathological data of microalbuminuria IgA nephrology patients confirmed by renal biopsy and followed up more than 6 months were reviewed. The patients were divided into decreased serum C3 level group (34 cases, 25.19%) and normal serum C3 level group (101 cases, 74.81%) according to the serum C3 level. Twenty-four hours urine protein quantitative > 1 g, or normal serum creatinine level turning into abnormal level at renal biopsy, or doubling of serum creatinine level was defined as the end point of follow-up. Renal survival was calculated by Kaplan-Meier survival analysis and risk factors of progression were analyzed by Cox regression models. Results Total of 135 microalbuminuria IgA nephrology patients were followed up successfully, with an average follow-up time (53.4 ± 21.9) months. There were 27 cases (79.41%) and 32 cases (31.68%) in the decreased serum C3 level group and the normal serum C3 level group respectively at the endpoint. Kaplan-Meier survival analysis showed that the median survival time was significantly shorter in decreased serum C3 level group compared with that in normal C3 level group (46.7 ± 9.1) months vs. (68.4 ± 9.9) months, P =0.014. Cox regression analysis showed that abnormal serum creatinine (RR = 1.147, 95% CI 1.129-1.395, P = 0.008), decreased serum C3 level (RR=1.028, 95%CI0.672-1.495, P=0.039), urine protein quantitative>1 g/24 h (RR=2.066, 95%CI1.242-3.838, P=0.006) and renal biopsy pathological indicators Lee classⅢ-Ⅴ(RR=2.820, 95%CI1.249-5.638, P=0.041), glomerular sclerosis or adhesions (RR=1.232, 95%CI 1.065-1.520, P = 0.040), renal interstitial atrophy or interstitial fibrosis (RR = 2.604, 95% CI1.748- 4.104, P = 0.037), endocapillary cell proliferation (RR = 0.872, 95% CI 0.491- 1.275, P =0.042), crescentic (RR = 1.528, 95% CI 1.073- 2.385, P = 0.009) affected prognosis of microalbuminuria IgA nephropathy as the independent risk factors. Conclusions The clinical and pathological features in patients of microalbuminuria IgA nephropathy with decreased serum C3 level is more severe, and the prognosis is poor. The patients should be followed up closely and early intervention treatment and early active control of microalbuminuria should be done at the same time.