Prevalence, Molecular Pathotypes, Clinical Outcomes And Antibiotic Profiles Of Escherichia Coli, Salmonella And Shigella From Diarrhoea Inpatients Aged Below Five Years At Moi Teaching And Re

ABSTRACT

Diarrhoea remains a major cause of mortality and morbidity worldwide. Diarrhoea in low income settings is attributed to bacterial enteropathogens but viruses and parasites may also be involved. Children infected with HIV are known to experience severe, persistent and recurrent diarrhoea requiring frequent and prolonged usage of antibiotics. However, the actual cause diarrhoea in HIV positive and negative children is unknown. This was a cross-sectional study involving 216 diarrhoea cases aged below five years admitted at Moi Teaching and Referral Hospital. The study determined prevalence, molecular pathotypes, antibiotic profiles of bacterial enteropathogens and clinical outcomes of in-vivo antibiotic susceptibility in relation to HIV serostatus. Fresh stool was collected and processed using standard microbiological methods and multiplex PCR confirmed pathotypes and virulence genes in bacterial isolates. Antibiotic susceptibility to ampicillin, amikacin, ceftriaxone, cefuroxime, ceftazidime, gentamicin, cotrimoxazole, cefipime, ciprofloxacin and imipenem was evaluated using Kirby-Bauer disc-diffusion. Chi-square (χ2) was used to test for associations between independent and dependent variables while Kruskal-Wallis test compared means between groups at p ≤ 0.05. Prevalence of diarrhoea was 15.6% while 118(54.6%) of stool samples yielded bacteria. Frequency of bacterial diarrhoea was lower among HIV positive 41(34.7%) compared to HIV negative cases 77(65.3%) with highest frequency among cases aged 0-24 months. The main bacterial pathogens were Escherichia coli 105(88.9%), Shigella 6(5.1%) and Salmonella 5(4.2%), while pathotypes were EAEC 21(58.3%), EPEC 6(16.7%), EHEC 4(11.1%), EIEC 3(8.3%), ETEC 2(5.6%), Shigella flexneri 3(50%), S. dysentriae 3(50%), S. typhimurium 4(80%) and S. typhi 1(20%). Virulence genes detected included EHEC (stx1, stx2), ETEC (elt, est) EPEC bfp, EAEC aatA, EIEC ipaH, Salmonella invA, and Shigella ipaH and vir F genes. Most virulence genes were associated with acute diarrhoea while Shigella ipaH, EPEC bfp, EAEC aatA, Shigella virF and Salmonella invA were linked to antibiotic resistance. Escherichia coli, Salmonella and Shigella strains in HIV negative cases were highly susceptible to cefuroxime, ceftazidime, cefepime and amikacin respectively compared to HIV positive cases, with high overall resistance to ampicillin and cotrimoxazole. Diarrhoea persisted in 5(4.3%) of cases, 18(15.5%) died and 93(80.3%) improved and were discharged with medication with better outcomes in HIV negative cases. Cefuroxime, ceftazidime, ciprofloxacin, cefipime and amikacin are effective and may be incorporated into treatment regimens. The study recommends definitive diagnosis and determination of antibiotic profiles for effective management of diarrhoea and prevention of multi-drug resistance. The findings shall contribute to critical development of interventions to monitor, prevent and control childhood diarrhoea.