The Associations Between The Measuring Of TGF-β1, IL-18 And NGAL In Serum And Urine With The Steroid-resistant Nephrotic Syndrome

Objective: To detect the transforming growth factor β1(TGF-β1),interleukin-18(IL-18)and neutrophil genatinase-association lipocalin(NGAL)concentration in serum and urine samples of children with primary nephritic syndrome before use of glucocorticoid and after 1 and 4 weeks of treatment with glucocorticoid, in order to verify whether it could predict SRNS.Methods: The subjects were obtained from 84 children with PNS and 40 healthy children for control group. During December 2012 to February 2014, the serum and urine samples before use of glucocorticoid and after 1 and 4 weeks of treatment of 84 children with PNS(SSNS 58 case, SRNS 26 case) was collected in Tianjin Children’s Hospital. Enzyme-linked immunosorbent assay was used to quantify the serum and urine TGF-β1, IL-18 and NGAL concentration of 84 children with PNS and 40 healthy children. Meanwhile, urinary creatinine(Cr) concentration was measured, and urine TGF-β1, IL-18 and NGAL concentration in a single urine collection was corrected according to the urinary Cr excretion.SPSS19.0 software was used to analyze the data.Results: 1. The comparison of the clinical data before GC treatment between the SSNS and SRNS group There was no significant difference of sex, age, weight, 24 UP, blood Alb, TCho, Cr and BUN between SSNS group and SRNS group(P﹥0.05). 2. The serum and urine TGF-β1, IL-18 and NGAL levels in SSNS, SRNS and control groups before and after GC treatment ①The levels of serum and urine TGF-β1, IL-18 and NGAL were significantly increased in SSNS group and SRNS group compared with control group either before GC treatment or after 1 week GC treatment(P﹤0.05). Compared with control group, the serum and urine TGF-β1, IL-18 and NGAL levels of SSNS group had no significantly difference after 4 weeks GC treatment(P﹥0.05), but their of SRNS group was increased after 4 weeks GC treatment conversely(P﹤0.05). ②There was no significant difference of serum and urine TGF-β1, IL-18 andNGAL between SSNS group and SRNS group before GC treatment(P ﹥ 0.05). Compared with SSNS group the serum and urine TGF-β1, IL-18 and NGAL of SRNS group was increased after 1 week and 4 weeks GC treatment(P﹤0.05). ③Compared with the same group before GC treatment, the SSNS group had a trend of gradual decline in serum and urine TGF-β1, IL-18 and NGAL concentration after 1 and 4 weeks of treatment with GC(P﹤0.05); the SRNS group had no statistically significant difference before use of GC and after 1 and 4 weeks of treatment(P﹤0.05). 3.Correlation analysis The urine TGF-β1, IL-18 and NGAL levels were positively correlated with urinary protein(r =0.489、0.453、0.389, P﹤0.01). 4. ROC curve analysis The ROC curve based on the levels of serum TGF-β1, IL-18 and NGAL after 1 week of treatment were constructed, and the areas under the curve(AUC) were 0.610, 0.811,0.904, and the sensitivity and specificity were 50%vs73%,100%vs70% and 100%vs82%. The ROC curve based on the levels of urine TGF-β1, IL-18 and NGAL after 1 week of treatment also were constructed, and the areas under the curve were 0.651, 0.721, 0.636, and the sensitivity and specificity were 73%vs40%,81%vs70% and 54%vs72%.Conclusion: 1. The increase of serum and urine TGF-β1, IL-18 and NGAL associated with the onset of PNS. These indicators could predict SRNS if they stay at high levels. 2.As one of the indicators to predict SRNS, IL-18(serum and urine) and NGAL(serum) shows higher value in the early.As soon as the serum IL-18 reach 0.811μg/L, urine IL-18/Cr reach 4.75×10-2 ng/μmol and serum NGAL reach 55.68μg/L, we should alert the SRNS.