Evaluation of evidence-based urinalysis reflex to culture criteria: Impact on reducing antimicrobial usage

• Published in: International journal of infectious diseases 2021-01, Vol.102, p.40-44
• Main Authors: Ourani, Mohammad, Honda, Nathan S., MacDonald, William, Roberts, Jill
• Format: Article
• Language: English
• Subjects: Anti-Infective Agents - therapeutic use; Antibiotics usage; Antimicrobial resistance; Drug Prescriptions - statistics & numerical data; Drug Resistance; Evidence-Based Practice; Female; Humans; Logistic Models; Male; Multivariate Analysis; Predictive Value of Tests; Prospective Studies; Urinalysis; Urinalysis reflex criteria; Urinary tract infections; Urinary Tract Infections - drug therapy; Urinary Tract Infections - microbiology; Urinary Tract Infections - urine; Urine - microbiology
• ISSN: 1201-9712; 1878-3511
• DOI: 10.1016/j.ijid.2020.09.1471

•Antimicrobial resistance is spreading rapidly and is a major problem for public health.•Antibiotic misuse is the main contributing factor to the development of antimicrobial resistance.•In many laboratory practices, urinalysis procedures are outdated and suboptimal, therefore leading to inadequate laboratory results.•Our laboratory has implemented evidence-based urinalysis reflex criteria to improve practice and improve laboratory results. To implement evidence-based urinalysis (UA) reflex criteria and to evaluate the impact of the intervention on reducing unnecessary antibiotic usage. A prospective intervention study was conducted on 4130 urine samples that were subjected to UA during March to May 2020. Results were analyzed in order to evaluate the effectiveness of newly implemented evidence-based criteria in predicting positive urine cultures. The intervention involved implementing evidence-based UA reflex criteria to ensure a high predictive value of the UA reflex parameters. Multivariable logistic regression was utilized to evaluate the effectiveness of these UA parameters in predicting positive urine cultures and to assess the impact of the new UA criteria on antibiotic usage. A total of 4130 patient samples were included in the study; 60.1% (n = 2484) were from female patients and 39.9% (n = 1646) were from male patients. The total number of negative urine reflex samples was 3116, which accounted for 75.4% of the total UA reflex samples. In contrast, 24.6% of the urine reflex samples (n = 1014) returned positive UA results and were reflexed to urine culture. Among the urine samples that were cultured, 9% (n = 91) were negative urine cultures, while 91.0% (n = 923) were positive urine cultures. Chi-square analysis indicated highly statistically significant associations between the combination parameters of (≥5 white blood cells (WBCs) and positive nitrite) and positive urine cultures (Chi-square = 516.428, p < 0.001) and (≥5 WBCs and moderate or large esterase) and positive urine cultures (Chi-square = 503.387, p < 0.001). Additionally, Chi-square analysis indicated a highly statistically significant association between the combination parameters of (≥5 WBCs and ≥1 bacteria) and positive urine cultures (Chi-square = 434.806, p < 0.001). The statistical analysis showed that the implementation of evidence-based UA reflex criteria significantly decreased the number of urine cultures performed and potentially decreased the number of patients inappropria