The Prevalence of Shiga Toxin-1 in Non-Shigella Dysenteriae Isolates Collected from Diarrhea Samples in Patients, Ahvaz, Iran

Background: Acute diarrhea is a major public health problem, particularly in developing countries. Shigellosis is one of the substantial causative agents of microbial dysentery and still has a remarkable prevalence, particularly in areas with poor hygienic infrastructures. The probable existence of the deadly Shiga toxin (Stx) protein in some Shigella strains would manifest life-threatening clinical symptoms of the infection. Methods: The aim of this study was to determine the presence of Shigella toxin 1 (Stx1) in isolated from patients with diarrhea. Totally, 227 Shigella species, including 60 S. flexneri, 157 S. sonnei, and 10 S. boydii were collected from diarrheal patients in the tropical infectious diseases research center of Ahvaz, Iran, during 2013-2015. The isolates were collected mostly from the intensive care unit, infectious disease, and surgery settings. The isolates were identified, and the polymerase chain reaction (PCR) was performed to detect the stx gene. Results: The results indicated that none of them encode the stx1 gene. Conclusion: Isolates of this study were not capable of stx1 encoding. Future investigations should consider the relations between other Shigella species and Shigella toxin in Iran.