The Frequency of Shiga Toxin Producing Escherichia coli in Patients with Urinary Tract Infection in Iran: Systematic Review and Meta-Analysis

Abstract

Background and Objectives: Escherichia coli is the main cause of urinary tract infection regardless of age. If it harbors shiga toxin, hemolytic uremic syndrome may occur. The aim of this study was to determine the incidence and prevalence of Shiga Toxin producing E. coli (STEC), as a cause of urinary tract infection in Iran. Methods: Major medical search engines, Iranian scientific search engines, and Iranian databases for thesis were searched for relevant English or Persian keywords for urinary tract infection, shiga-toxin Escherichia coli, and hemolytic uremic syndrome in Iran, which were published between 1985 and 2017. The study was followed by the PRISMA statement. Point prevalence and proportion were calculated by random effect and I2 for heterogeneity and expressed as 95% confidence intervals. MedCalc version 15 and SPSS IBM were used for statistical analysis. Results: A total of six articles with 1,111 positive E. coli urine cultures met all the inclusion criteria and were eligible for the final analysis. All studies had a cross-sectional design. The qualities of two studies were poor with low to moderate risk of bias. Considering 32 samples reported as positive for STEC, the pooled prevalence for E. coli associated UTI was 3.46% (95% CI, 0.89 to 7.65, I2 = 86%). The study was heterogeneous for publication bias. Conclusions: This review indicated that STEC constituted some percentage of uropathogenic E. coli that required to be considered during culture processing and longer clinical follow up of the patients for the occurrence of STEC-related morbidity.