Isolation and Identification of Common Nosocomial Microorganisms in Diagnostic Laboratories in Umuahia, Abia State

Abstract

Diagnostic laboratories play a crucial role in the healthcare system, as they provide important diagnostic services to patients and healthcare providers. However, these facilities can also be a source of nosocomial infections if proper infection control measures are not implemented. The purpose of this study is to identify and isolate the most prevalent laboratory-acquired pathogens in five selected diagnostic laboratories and health-associated facilities. A simple random sampling technique was employed in the study. Five different medical laboratories within Abia state were used, including the Veterinary Microbiology Laboratory, University Health Centre, Federal Medical Centre, Umuahia, Amara-Jane Hospital Laboratory and V-max Laboratory, Aba. A total of two hundred samples were collected for the study, with each health facility contributing fifty samples. The samples were inoculated onto different media, namely mannitol salt agar, Salmonella-Shigella agar, Eosin methylene blue agar, and MacConkey agar and incubated at 37 °C for 24 hours. The isolates were then subjected to different biochemical tests such as Gram stain reaction, coagulase, Simmon’s citrate, urease, methyl red, Voges-Proskauer and indole tests. Bacterial growth occurred in 143 isolates (71.5%). The microorganisms most frequently isolated were Escherichia spp, Salmonella spp, Klebsiella spp and Staphylococcus spp, with Escherichia spp being the most frequent and significant at 83 isolates (58.7%), while the least frequent was Proteus spp at 8 isolates (5.5%). The Gram-negative bacilli isolated were high 103(72%), while the Gram-positive cocci were low 40(28%). The most frequently isolated organism across the five laboratories was Escherichia spp (74%) from the V-max laboratory, while the least isolated organism was Proteus spp (0%) across three laboratories, namely Veterinary Microbiology Laboratory, Amara Jane laboratory and V-max laboratory. The outcome of the study shows that P> 0.821, hence no statistically significant difference in contamination between laboratories (P-value set at 0.05). A high level of hygiene and adequate aseptic conditions should be observed to reduce the frequency of isolation of microorganisms, especially Escherichia coli.