Clinical Significance of Urine α1-Microglobulin-to-Microalbumin Ratio in the Diagnosis of Tubulointerstitial Diseases in Children

LIN Tiantian; CHEN Chaoying

doi:10.3639/j.issn.2095-3097.2025.04.024

Abstract：Objective To investigate the clinical significance of urine α1-microglobulin(α1-MG)—to—microalbumin(MA)ratio in the diagnosis of tubulointerstitial diseases in children.Methods Twenty-five children with tubulointerstitial diseases in the Department of nephrology of the Capital center for children's health,Capital Medical University from January 2014 to December 2022 were retrospectively collected,serving as the observation group.Urine α1-MG,urine MA and urine protein electrophoresis results were measured.The urine α1-MG/MA ratio was analyzed,and its correlation with the percent-age of low molecular weight protein(LMWP)in urine protein electrophoresis was analyzed by Pearson correlation coefficient analysis.Twenty-five children with primary nephrotic syndrome who were initially treated during the same period were selected as the control group.The data of both groups were compared.Multivariate logistic regression analysis was used to identify in-fluencing factors for tubulointerstitial diseases in children.With the final clinical diagnosis as the standard,kappa coefficient analysis was adopted to explore the value of urinary α1-MG/MA in the diagnosis of tubulointerstitial diseases in children.Results The biomarkers of kidney injury in the observation group were mainly elevated urine α1-MG and urine α1-MG/MA＞1.Pearson correlation coefficient analysis suggested that urine α1-MG/MA in the observation group was positively cor-related with the percentage of LMWP in urine protein electrophoresis(r=0.953,P＜0.01).There were significant differenc-es in urine α1-MG,urine MA,α1-MG/MA and LMWP percentage between the observation group and the control group(P＜0.01).The biomarkers of kidney injury in the control group were mainly elevated urine MA and urine α1-MG/MA＜1.Multivariate logistic regression analysis indicated that urine MA(OR=0.257,95％CI:0.082-0.808,P=0.021)and α1-MG/MA(OR=8.802,95％CI:1.842-42.059,P=0.007)were independent factors in the diagnosis of tubulointerstitial diseases(P＜0.05).Using urine α1-MG/MA＞1 as the criterion,the ratio showed good consistency with the final clinical diagnosis(kappa＞0.4),with a sensitivity,specificity,and accuracy of 72.00％,96.00％and 84.00％,respectively.Conclusion Urine α1-MG/MA ratio＞1 can indicate the predominance of LMWP in urinary protein,serve as a screening tool for tubulointerstitial diseases in children,and demonstrate clinical significance for early diagnosis of these conditions.