To investigate the value of urinary YKL-40 in the early diagnosis of acute urinary tract infection in newborn and its correlation with other clinical indicators.

Eighty-eight children with suspected acute urinary tract infection (UTI) who were admitted to our hospital from January 2015 to June 2018 were enrolled in the study. 10 mL of clean mid-stage urine was taken and placed in a sterile test tube. The test was carried out in 1 hour, and the components were analyzed after bacterial culture. According to the results of bacterial culture, the children were divided into the control group (negative bacterial culture, n=49) and the observation group (positive bacterial culture, n=39), and the two groups were compared.

There were no significant differences in Scr and eGFR between the two groups (P>0.05). The ESR and CRP in the observation group were significantly higher than those in the control group (P<0.05). The level of urinary YKL-40/Cr in the observation group was significantly higher than that in the control group (P<0.05). There was no significant difference in the level of YKL-40/Cr between the positive and negative pus in the control group (P>0.05). There were no significant differences in the levels of YKL-40/Cr between the positive and negative patients with pyuria, hematuria, proteinuria, nitrite, hydronephrosis and vesicoureteral reflux in the observation group (P>0.05). The results of ROC curve analysis showed that the diagnostic cutoff value of urine YKL-40/Cr for UTI was 123.25 pg/mg, AUC was 0.793,P=0.023, sensitivity was 82.05%, and specificity was 90.04%. Correlation analysis showed that YKL-40/Cr was not significantly associated with gender, BMI index, ESR, eGFR, hematuria, proteinuria, hydronephrosis, photon deficiency in DMSA, and vesicoureteral reflux (P>0.05). There was a significant negative correlation between birth days and duration of fever (r<0,P<0.05), and a significant positive correlation with WBC count, CRP, pyuria and nitrite positive (r>0,P<0.05).

Urine YKL-40 has a high diagnostic value for early diagnosis of acute urinary tract infection in newborn. The level is negatively correlated with age and duration of fever, and positively correlated with WBC count, CRP, pyuria and nitrite positive.

Urinary Tract Infections; Infant, Newborn; YKL-40