Atiyeh Asadpour, Richa Sharma, Jana Suklan, Stephen P Kidd, Julie Hart, Alexander Daniel Edwards, Sarah Helen Needs
Although increasing numbers of studies report the accuracy of direct-from-urine AST, heterogeneity prevented systematic comparison of methods or detailed meta-analysis. Many studies reported overall accuracy >90% CA for urine samples containing a single Gram-negative organism across several direct-from-urine AST methods, offering potential time saving compared with current methods. However, as single organism samples represent only a subset of urines taken from UTI patients, additional studies-that include analysis of samples containing mixed cultures and Gram-positive isolates-are still required.
BACKGROUND: Antimicrobial susceptibility tests (AST) are vital to guide antibiotic selection to treat bacterial infections, including urinary tract infections (UTI). Current laboratory AST takes at least 2 days. Direct testing of urine samples could speed up testing, with rapid reporting aiding timely treatment.
METHOD: A scoping review was conducted to identify studies assessing the accuracy of direct-from-urine AST, and map the breadth of evidence. Studies that measured overall categorical agreement (CA) compared to a reference method were selected, and the reported accuracy, the type of AST method and study methodology assessed.
RESULTS: In total, 33 studies were identified that met the inclusion criteria (1976-2024). These reported overall CA for direct-from-urine AST ranging from 78.7% to 100% compared to a reference method. These studies varied in the AST method used; in urine sample collection, origin and processing; in the antibiotics evaluated; in study design and data analysis. The most common AST method evaluated was direct-from-urine disc diffusion. Most studies reported accuracy only for samples containing a single Gram-negative organism.
CONCLUSION: Although increasing numbers of studies report the accuracy of direct-from-urine AST, heterogeneity prevented systematic comparison of methods or detailed meta-analysis. Many studies reported overall accuracy >90% CA for urine samples containing a single Gram-negative organism across several direct-from-urine AST methods, offering potential time saving compared with current methods. However, as single organism samples represent only a subset of urines taken from UTI patients, additional studies-that include analysis of samples containing mixed cultures and Gram-positive isolates-are still required.