The Prevalence of Shiga Toxin-producing Escherichia Coli in Patients with Gastroenteritis in Iran, Systematic Review and Meta-analysis

Shiga toxin induced Escherichia Coli (STEC) is associated with chronic kidney disease or neurologic disability. The aim of this study is to determine the prevalence of STEC identified in human studies in Iran. Search engines of PubMed, EMBASE, OVID, SCOPUS, Web of Science, Google Scholar, IranMedex, MagIran, SID and ganj.irandoc were used. All human studies with stool or rectal swap samples evaluated for STEC and the outcome of HUS in Iran, which had been published between 1985 and 2017, were included. Chi-square and I2 statistic tests were applied to assess between-studies heterogeneity. Pooled prevalence and odd ratio were calculated using random effect models. A total of 30 articles containing 23379 samples were included for the final analysis. The design of study was cross sectional in 16, case control in 13 and one was cohort. The pooled prevalence of STEC was 7% (95% CI, 5 – 11; I2 = 98.3%). In subgroup analysis, the pooled prevalence was 8% (95% CI, 4 – 13; I2 = 97.55%) in children but 4% (95% CI, 2 – 7; I2 = 97.66%) in adults. The odds of patients with diarrhea having had STEC were 7.06 times the odds of healthy subjects (pooled o‎r = 7.06, 95% CI: 3.66-13.61). Patients with bloody diarrhea less likely to have positive STEC than patients with non-bloody diarrhea (pooled o‎r = 0.33, 95% CI: 0.10-1.02). STEC was prevalent in diarrheic patients and the rate increased in recent years. The highest contamination was seen in East-South of Iran. Public health intervention is mandatory to eliminate it effectively.