Demographic trends and antimicrobial susceptibility pattern of Shigella species - A 14-year study

Abstract Introduction: Shigellosis is the major factor responsible for dysentery among children who are <5 years of age. Shigella dysenteriae are responsible for outbreaks and epidemics. Shigella flexneri and Shigella sonnei are the predominant species known to cause endemic infections in developing and developed countries. One of the main concerns about the increase in Shigella infections is their ability to easily acquire antibiotic resistance. Objective: The objective of the present study was to determine the demography and antibiotic susceptibility pattern of Shigella species over 14 years in a tertiary care center in Central Kerala. Materials and Methods: This was a cross-sectional retrospective study which was conducted in the department of microbiology from January 2009 to November 2022. 4418 stool samples from patients with dysentery were collected and sent for culture. Sixty-six isolates of Shigella species were obtained and their antibiotic susceptibility pattern was determined using standard microbiological methods. The data were analyzed using Statistical Package for the Social Sciences (SPSS) Software version 28 (IBM SPSS Statistics version:28.0.0.0 New York, USA) after entering in Microsoft Excel. Results: Sixty-eight percent of the affected population were children below 15 years. The period prevalence of Shigella species in the present study was 1.5%. Among the Shigella species, 66% of the isolates were S. sonnei , 32% were S. flexneri . Forty of the 66 isolates were multidrug resistant. Conclusion: S. sonnei has been found to be the predominant cause of shigellosis in the present study though in tropical countries S. flexneri is known to be the most common causative agent. Many isolates were multidrug resistant which highlights the importance of stopping the over-the-counter sale of antibiotics and prescribing antibiotics judiciously.