Objective To determine the added diagnostic value of dipsticks for urinary tract infections (UTI) in acutely hospitalised individuals. Design Prospective population-based cohort study. Setting North Denmark. Participants All adults (≥18 years) examined with dipsticks at emergency departments in North Denmark Region from September 20 through 23 October 2021. Main outcome measures UTI was defined as ≥1 symptom of new-onset frequency, dysuria or suprapubic tenderness combined with a positive urine culture. Positive dipsticks were defined as any reaction for leucocyte esterase and/or nitrite. Results Dipsticks were used in 1052/2495 (42%) of acutely hospitalised patients with a median age of 73 years (IQR 57–82) and 540 (51%) were female. Overall, 89/1052 (8%) fulfilled the UTI criteria and urine cultures were done in 607/1052 (58%) patients. Among patients examined with both dipstick and urine culture, sensitivity and specificity for UTI were 87% (95% CI 78% to 93%) and 45% (95% CI 41% to 50%). Positive and negative predictive values were 21% (95% CI 17% to 26%) and 95% (95% CI 92% to 98%), whereas positive and negative likelihood ratios were 1.58 (95% CI 1.41 to 1.77) and 0.30 (95% CI 0.18 to 0.51). Pretest probabilities of UTI ranged from 29% to 60% in participants with specific UTI symptoms with corresponding post-test probabilities of 35–69% if dipsticks were positive and 12–27% if dipsticks were negative. Results remained comparable if final clinical diagnosis was used as outcome among all patients examined with dipsticks. Modified Poisson regression yielded an adjusted relative risk of 4.41 (95% CI 2.40 to 8.11) for empirical antibiotics for UTI in participants without specific UTI symptoms and a positive dipstick. Conclusions Dipsticks yielded limited clinical decision support compared with a symptom-driven approach in this study and were independently associated with excess antibiotics for UTI. Data are available upon reasonable request and obtainment of approvals from Danish healthcare authorities. Data can be shared with other researchers upon obtainment of approvals from Danish healthcare authorities.

中文翻译：

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试纸对急症住院患者尿路感染的诊断准确性：一项基于人群的前瞻性观察队列研究


目的 确定试纸对急症住院患者尿路感染 (UTI) 的附加诊断价值。设计基于人群的前瞻性队列研究。设置北丹麦。参与者 2021 年 9 月 20 日至 10 月 23 日期间，所有成年人（≥ 18 岁）在丹麦北部地区的急诊室用试纸进行检查。 主要结果指标 UTI 定义为≥1 种新发频率、排尿困难或耻骨上压痛症状，并伴有阳性结果。尿培养。阳性试纸定义为白细胞酯酶和/或亚硝酸盐的任何反应。结果 1052/2495 (42%) 名急症住院患者使用了试纸，中位年龄为 73 岁 (IQR 57-82)，其中 540 名 (51%) 为女性。总体而言，89/1052 (8%) 患者符合 UTI 标准，607/1052 (58%) 患者进行了尿液培养。在同时使用试纸和尿培养进行检查的患者中，UTI 的敏感性和特异性分别为 87%（95% CI 78% 至 93%）和 45%（95% CI 41% 至 50%）。阳性和阴性预测值分别为 21%（95% CI 17% 至 26%）和 95%（95% CI 92% 至 98%），而阳性和阴性似然比分别为 1.58（95% CI 1.41 至 1.77）和 0.30 （95% CI 0.18 至 0.51）。对于具有特定尿路感染症状的参与者，尿路感染的预测试概率为 29% 至 60%，如果试纸呈阳性，相应的测试后概率为 35-69%，如果试纸呈阴性，则相应的测试后概率为 12-27%。如果使用最终的临床诊断作为所有使用试纸检查的患者的结果，结果仍然具有可比性。改良泊松回归得出，在没有特定尿路感染症状且试纸呈阳性的参与者中，尿路感染经验性抗生素的调整相对风险为 4.41（95% CI 2.40 至 8.11）。 结论 在本研究中，与症状驱动的方法相比，试纸产生的临床决策支持有限，并且与尿路感染的过量抗生素独立相关。数据可根据合理请求并获得丹麦医疗机构的批准而提供。获得丹麦医疗当局的批准后，可以与其他研究人员共享数据。