Isolation and Characterization of Toxigenic Clostridium Difficile in Selected Outpatient Health Facilities Within Nairobi County

Abstract

Background In the last four decades, the spectrum encompassing the epidemiology and management of Clostridium difficile associated diseases (CDAD) has changed progressively. These changes resonate with heightened rates of unprecedented incidences, morbidity and mortality of novel community-acquired Clostridium difficile infections with severity index matching superbugs in fatal nosocomial infections and multi-drug resistance. Significant risk factors in CACDI are indefinite and challenging primarily on pathological relevance of toxigenic and non-toxigenic strains, pathways of transmission, growing antimicrobial resistance and treatment failure hypothesized on the emergence of epidemic strains and other independent risk factors. Clostridium difficile has gained public health significance in the community settings necessitating surveillance and monitoring the prevalence, risk factors and strains responsible for this. Objective To evaluate the prevalence, the risk factors of community-acquired Clostridium difficile infection and profile the toxin genes of the recovered isolates. Methodology This was a cross-sectional prospective study conducted between August and November 2019 at the Mama Lucy Kibaki and Mbagathi referral and teaching hospitals within Nairobi County. From a total of 342 diarrhoeal samples, 301 were processed and analyzed. Subsequently, clinical and socio-demographic data was collected at the time of the illness using a guided structured questionnaire. Growth on CHROMagar was assessed for colonial morphology by ultraviolet light fluorescence and gram staining. DNA extraction was done using the Meridian Bioscience ISOLATE II Genomic DNA Kit following the manufacturer’s instructions, after which the tcdA, tcdB and the binary toxin CDTa/b genes were detected by multiplex conventional PCR. Data was entered into excel spreadsheets and exported for statistical analysis into the IBM SPSS statistics Version 20. Results In all 301 samples tested, 36 (12.0%) were culture positive for Clostridium difficile and 35 (11.6%) were positive for toxins genes. Mixed enteropathogens and parasites were not characterized. Age of participants varied from 1-62 years, and mean age was 27.2±15.7, with more than half of the study participants being females 50.6. The patients presented with bloating 36%, cramping 33%, bloody 13%, and 6% of fever, headache and vomiting. Among the 36 (12.0%) CACDI positive, 58.3% were males, mean age 24.9 ±13.7 years. Potential risk factors for CACDI were use of NSAIDs (p=0.004), HIV/AIDs as a comorbidity (p=0.001), history of organ transplant (p=0.04), keeping a pet or a farm animal (p=0.03) and the use of acid suppressants (p=0.005). Symptoms in admixture of diarrhoea that were telltale signs for CDI were gastrointestinal bleeding presenting as bloody stool P=0.003), abdominal cramping (p=0.002). The toxins profile observed included tcdA+/tcdB+/CDTa-/b- 18 (50%), tcdA-/tcdB+/CDTa+/b+ 9 (25%), tcdA-/tcdB-/CDTa-/b- 1 (3%) and tcdA-/tcdB+/CDTa+/b+ 3 (8%) and tcdA+/tcdB+/CTDa+/b+ 5 (14%). Conclusion CACDI seems to occur across all age groups as the risk factors keep evolving yet the public health impact largely remains incompletely defined especially in developing countries calling for active surveillance, awareness, early and routine testing and containment strategies.