Division of Pediatric Neonatology, Department of Pediatrics, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
Department of Business Management, National Sun Yat-Sen University, No.70 Lien-hai Road, Kaohsiung, Taiwan; Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Taiwan.
J Microbiol Immunol Infect. 2024 Aug;57(4):609-616. doi: 10.1016/j.jmii.2024.05.008. Epub 2024 May 28.
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.
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.
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.
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.
尿液白细胞镜检是尿路感染（UTI）最常用的常规筛查试验之一。然而，据观察，10-25%的 UTI 患儿存在脓尿缺失。本研究旨在确定<4 个月龄婴儿中脓尿阴性 UTI 的相关因素。
这是一项回顾性的病例对照研究，共纳入了 157 例<4 个月龄的 UTI 患儿。所有患儿均进行了尿沉渣和尿培养检查，采集方法为经尿道导尿。根据尿沉渣结果，将患儿分为脓尿阳性 UTI 组和脓尿阴性 UTI 组。分析两组患儿的临床特征和结局。
在 157 例 UTI 患儿中，脓尿阴性 UTI 的患病率为 44%。与脓尿阴性 UTI 相关的显著危险因素包括非大肠埃希菌病原体、年龄较小、就诊前发热时间较短、就诊时白细胞计数较低以及无镜下血尿。
我们发现非大肠埃希菌尿病原体是与脓尿阴性 UTI 最相关的因素。脓尿缺失不能排除对婴儿的 UTI 诊断，对发热或表现不佳的婴儿进行尿沉渣和尿培养检查是合理的。
