The Correlation Between Serum Uric Acid And Tubulointerstitial Lesions In The Early Stage Of Primary Glomerulonephritis

Objective: To investigate the correlation between the level of serum uric acid(UA)and tubulointerstitial lesions in patients with primary glomerulonephritis.Methods: 654 cases of primary glomerulonephritis with eGFR ? 60 ml / min / 1.73m2 which is diagnosed by renal biopsy were included in this research.Their clinical and pathological data were analyzed retrospectively.The pathological changes in tubulointerstitial lesions were classified according to the Katafuchi semiquantitative scoring criteria: tubulointerstitial lesions score range 0 to 9 points,including renal tubular atrophy(0 to 3 points),interstitial fibrosis(0 to 3 points),inflammation of tubulointerstitial(0 to 3 points);severity of tubulointerstitial lesions were divided into noninvasive(0 points),mild(1 to 3 points),moderate(4 to 6 points),severe(7 to 9 points).Multivariate logistic regression was used to analyze the independent correlation between clinical parameters and tubulointerstitial lesions.We divide the renal tubulointerstitial lesions of primary glomerulonephritis into two gropes : normal group and lesion group.The ability of serum uric acid to identify tubulointerstitial lesion was evaluated by the receiver operating characteristic curve,and the best diagnostic threshold was selected.At the same time,IgA nephropathy,minimal change disease and idiopathic membranous nephropathy were analyzed as subgroup.If it is proved that serum uric acid was independently associated with tubulointerstitial lesion,then we can further analyze that its ability to identify tubulointerstitial lesion by the receiver operating characteristic curve.Results: A total of 654 patients with primary glomerulonephritis were included,145 cases were minimal change disease(accounted for 22.2%),294 cases were IgA nephropathy(accounted for 45.0%),155 cases were idiopathic membranous nephropathy(accounted for 23.7%),20 cases were focal segmental glomerulosclerosis(accounted for 3.0%),31 cases were non IgA-mesangial proliferative glomerulonephritis(accounted for 4.7%),9 cases were mesangioproliferative glomerulonephritis among them(accounted for 1.4%);370 were males and 284 were females.According to the renal biopsy,144 cases of tubulointerstitial lesions were nomal(accounted for 22.0%),398 cases of mild tubulointerstitial lesions(accounted for 60.9%),112 cases of moderate to severe tubulointerstitial lesions(accounted for 17.1%).In primary glomerulonephritis,the higher level of serum uric acid,the more serious of tubulointerstitial lesions;and the lower level of eGFR,the more serious of tubulointerstitial lesions.Age,hyperuricemia and decreased glomerular filtration rate were independently associated with tubulointerstitial lesions of primary glomerulonephritis and were independent risk factors for tubulointerstitial lesions.The risk of mild tubulointerstitial lesions in patients with hyperuricemia was 1.743 times higher than those with normal serum uric acid levels,and the risk of severe tubulointerstitial lesions was about 2.534 times higher than those with normal serum uric acid levels.Serum uric acid level of man at the level of 392.7umol/L in the diagnosis of tubulointerstitial lesions,the sensitivity was 45.2%,specificity was 60.3%,serum uric acid level of women at the level of 307.3umol/L in the diagnosis of renal tubulointerstitial lesions,the sensitivity was 47.7%,specificity was 71.2%.In the early stage of IgA nephropathy subgroup analysis,hyperuricemia and decreased glomerular filtration rate were independently associated with tubulointerstitial lesions of IgA nephropathy and were independent risk factors for tubulointerstitial lesions.The risk of mild tubulointerstitial lesions in IgAN patients with hyperuricemia was 15.5 times higher than those with normal serum uric acid levels,and the risk of moderate to severe tubulointerstitial lesions was about 36.6 times higher than those with normal serum uric acid levels.In the early stage of IgA nephropathy,serum uric acid level of man at the level of 354.2umol/L in the diagnosis of tubulointerstitial lesions,the sensitivity was 79.4,specificity was 80%,serum uric acid level of women at the level of 239.8umol/L in the diagnosis of renal tubulointerstitial lesions,the sensitivity was 84.3%,specificity was 54.5%.Conclusion: 1.Age,hyperuricemia and decreased glomerular filtration rate were independently associated with tubulointerstitial lesions in early stage of primary glomerulonephritis,they were independent risk factors for those patients' tubulointerstitial lesions,and the risk of tubulointerstitial lesions in patients with hyperuricemia was several times higher than those with normal serum uric acid levels.2.Hyperuricemia and decreased glomerular filtration rate were independently associated with tubulointerstitial lesions in early IgA nephropathy,they were independent risk factors for these patients' tubulointerstitial lesions,those patients with hyperuricemia were significantly more likely to develop tubulointerstitial lesions than those with normal uric acid levels.3.The level of serum uric acid can be used as a clinical maker for detecting tubulointerstitial lesions in early stage of primary glomerulonephritis,especially in IgA nephropathy has a certain accuracy.