DIAGNOSTIC EFFICACY OF SERUM LOW GLYCOSYLATION IGA1 AND URINARY ANGIOTENSINOGEN DETECTION IN EARLY RENAL INJURY OF CHILDREN WITH HENOCH-SCHONLEIN PURPURA

Huanqin Cui^#, ^#, Weiyan Cai, Yi Yao, Yinyin Cao, Jiaju Xu^*

Department of Pediatrics, Yantai Yuhuangding Hospital, Yantai, PR China

Objective: The aim of this study was to analyze the diagnostic efficacy of serum low glycosylation IgA1 and urinary angiotensinogen detection for early renal injury in children with Henoch-Schonlein purpura (HSP). 

Methods: Sixty-one children with HSP treated in the pediatric ward of our hospital between January 2016 and December 2017 were selected, including 31 children with HSP comprising the HSP group, 30 children with HSP nephritis (HSPN) comprising the HSPN group, and 25 healthy children comprising the control group. The levels of blood urea nitrogen (BUN), creatinine (Cr), low glycosylation (Gd-IgA1), angiotensin (AGT), complement C3, and urine angiotensin (AGT) were measured. The correlations between Gd-IgA1, AGT, and renal function were analyzed using a Pearson correlation analysis. The relationship between Gd-IgA1/C3, uAGT/uCr, and early renal injury in children with HSP were analyzed using a multiple logistic regression model. An ROC curve was used to evaluate the sensitivity and specificity of Gd-IgA1/C3 and uAGT/uCr in the diagnosis of early renal injury in children with HSP.

Results: The ratio of serum Gd-IgA1 to Gd-IgA1/C3 in the HSPN group was significantly higher than that in the HSP group and normal control group (p<0.05). The serum Gd-IgA1 level in the HSP group was significantly higher than that of the normal control group (p<0.05). There was no significant difference in the ratio of Gd-IgA1/C3 between the HSP group and the normal control group (p>0.05). The uAGT/uCr level of HSPN group was markedly higher than that of HSP group and control group, and the difference was statistically significant (p<0.05). Moreover, the uAGT/uCr level in the HSP group was significantly higher than that of the control group (p<0.05). There was no significant difference in AGT level among the three groups (p>0.05). The Gd-IgA1/C3 ratio and uAGT/uCr level in the HSPN group was positively correlated with the serum Cr. The elevated levels of Gd-IgA1/C3 and uAGT/uCr were independent risk factors for HSPN occurrence (OR (95% CI) = 1.637 (1.068-2.435), OR (95% CI) = 1.952 (1.157-3.062)). The area under the ROC curve (AUC) of the serum Gd-IgA1/C3 and uAGT/uCr in the diagnosis of HSPN was 0.696 (95% CI: 0.531-0.816, p = 0.018) and 0.715 (95% CI: 0.543-0.832, p = 0.007), respectively. The selected cut-off points were 3.65 and 8.67, the corresponding sensitivities were 66.8% and 63.5%, and the specificities were 75.3% and 82.6%, respectively.

Conclusion: The serum Gd-IgA1 and uAGT/uCr levels of children with HSPN were significantly increased, indicating that Gd-IgA1 and uAGT may be closely related to the progression of HSP and renal injury in children, and can be used as an early diagnosis of HSPN to predict the progression and prognosis of HSP renal injury.