Risk factors for urinary tract infection in infants with unexplained hyperbilirubinemia: a single center case-control study.

Background: Urinary tract infection (UTI) is a potential cause of neonatal jaundice. Nevertheless, there remains a lack of consensus regarding appropriate screening practices for UTI in infants with hyperbilirubinemia. This study aimed to analyze a group of jaundiced infants to assess the prevalence of UTI, explore potential risk factors, and examine the impact of UTI on the course and severity of neonatal jaundice. Methods: This retrospective case-control study was conducted on 150 jaundiced infants (aged < 8 weeks) without a known etiology in the hyperbilirubinemia work-up. All subjects underwent phototherapy treatment and UTI screening by catheterization. They were then classified into UTI and non-UTI groups based on urine culture results, with a positive urine culture indicating the growth of ≥10,000 colony-forming units. The clinical characteristics and jaundice-related parameters of both groups were analyzed. Results: Among the 150 jaundiced patients, the prevalence of UTI was 29%. There was a significantly higher male predominance in the UTI group, and patients with UTI also had a significantly longer duration of hospitalization compared to those without UTI. Significant risk factors associated with UTI in jaundiced infants included male gender and a peak total bilirubin level higher than 18 mg/dl during hospitalization. The most common pathogens identified in urine culture were Escherichia coli (41.9%) and Enterococcus faecalis (30.2%). Conclusion: In cases of neonatal jaundice where the underlying cause is not evident, screening for UTI should be performed, particularly when associated risk factors or inadequate response to phototherapy is present.

Uropathogens and clinical manifestations of pyuria-negative urinary tract infections in young infants: A single center cross-sectional study.

BACKGROUND: Urine leukocyte count under microscopy is one of the most frequently used routine screening tests for urinary tract infection (UTI). Nevertheless, it is observed that pyuria is lacking in 10-25% of children with UTI. This study aims to determine the factors related to pyuria-negative UTI in young infants aged under four months old. METHOD: This retrospective cross-sectional study was conducted on 157 patients aged under 4 months old with UTI. All subjects had paired urinalysis and urine culture, which were collected via transurethral catheterization. According to the results of their urinalysis, the patients were then classified as UTI cases with pyuria and UTI cases without pyuria. The clinical characteristics and outcomes of both groups were analyzed. RESULT: Among the 157 UTI patients, the prevalence of pyuria-negative UTI was 44%. Significant risk factors associated with pyuria-negative UTI included non-E.coli pathogens, younger age, shorter duration of fever prior to hospital visit, lower white blood cell (WBC) count upon hospital visit, and absence of microscopic hematuria. CONCLUSIONS: We found that non-E.coli uropathogens were the strongest factor related to pyuria-negative UTI. The absence of pyuria cannot exclude the diagnosis of UTI in young infants, and it's reasonable to perform both urinalysis and urine culture as a part of the assessment of febrile or ill-looking young infants.