To investigate the clinical characteristics and risk factors of idiopathic membranous nephropathy(IMN)infection.

This study was a case-control study, a total of 193 patients with IMN were selected from the department of Nephrology of General Hospital of Northern Theater Command from October 2015 to October 2020, including 174 males and 19 females, aged 55.0(41.0, 61.0)years old, ranging from 22 to 78 years old.Base on the result of imaging examination, pathogenic microorganism examination and other clinical laboratory examinations, the patients were divided into infection group(n=41)and non-infection group(n=152), the clinical features and risk factors were analyzed.

Length of hospital stay[12.00(9.50, 16.00)d], C-reactive protein[8.18(3.00, 28.75)mg/L], and serum creatinine[75.00(66.50, 94.00)μmol/L]in the infection group were higher than those in the non-infection group[8.00(4.25, 12.00)d, 3.00(3.00, 3.00)mg/L, 71.00(62.00, 79.00)μmol/L], hemoglobin concentration[(133.10±3.06)g/L], albumin[(26.54±1.36)g/L], creatinine clearance[(84.12±5.31)ml·min^-1·1.73 m^-2], and CD4 positive T-lymphocytes[703.00(503.50, 1 045.00)/μl]in the infection group were lower than those in the noninfected group[(139.70±1.33)g/L, (32.04±0.65)g/L, (96.63±2.51)ml·min^-1·1.73 m^-2, 894.50(672.00, 1 182.75)/μl], the differences were statistically significant(P<0.05). Serum creatinine was an independent risk factor for IMN.Albumin and CD4 positive T-lymphocytes count were protective factors for IMN infection.The infection rate of the patients treated with steroid and cyclophosphamide was lower than that of the patients not treated with steroid and cyclophosphamide, and the difference was statistically significant(P<0.05). Albumin was significantly correlated with the cumulative amount of cyclophosphamide, the duration of steroid administration, and the cumulative total amount of hormones, and the difference was statistically significant(P<0.001). The sensitivity, specificity and accuracy of detection of infection by albumin were 77.0%, 53.7% and 68.0%.The sensitivity, specificity and accuracy of CD4 positive T-lymphocytes count were 82.2%, 46.3% and 63.8%.

IMN with decreased albumin, increased serum creatinine, and decreased CD4 positive T-lymphocytes are more likely to develop infectious disease.The patients with infection have longer hospital stay and more serious condition of renal disease.Treatment with glucocorticoids and cytoxan may reduce the incidence of infection in patients with IMN.

Idiopathic membranous nephropathy; Infection; Glucocorticoids; Immunosuppressive agents; CD4 positive T-lymphocytes