Prevalence of Hospital-Acquired Enterococci Infections in Two Primary-Care Hospitals in Osogbo, Southwestern Nigeria

Enterococci are opportunistic bacteria that become pathogenic when they colonize niches where they are not normally found. Of recent, they have become major cause of nosocomial infections, especially of the bloodstream, urinary tract and surgical sites. The aim of this study is to determine the point-prevalence rate of human enterococci infections among hospitalized patients in Osogbo, Nigeria. The study was conducted between January and June 2009 in two primary-care hospitals in Osogbo and involved a total of 118 patients who developed clinical evidence of infection at least 48 hours after hospital admission. Appropriate clinical samples were collected from the patients after an informed consent and cultured for isolation/biochemical identification of Enterococcus species at the Bacteriology Laboratory of Ladoke Akintola University of Technology, Osogbo using standard microbiological methods. There were 525 hospital admissions within the time frame of the study of which 118 (22.5%) developed hospital acquired infection (HAI); 58 (49.2%) of which cultured positive for bacterial pathogens. Enterococci were isolated from infective focus in 7 patients, giving a prevalence rate of hospital-acquired enterococci infection of 5.9%. Two species of Enterococcus were identified; Enterococcus faecalis from urinary tract infection (UTI) and surgical site infection (SSI) of 6 (85.7%) patients and Enterococcus faecium from UTI in 1 (14.3%) patient. Other bacteria recovered from other infective foci were Klebsiella spp 31.0%, Pseudomonas spp 20.7%, Staphylococcus aureus 17.2%, Escherichia coli 12.1%, Staphylococcus epidermidis 3.4%, Streptococcus pneumoniae 1.7% and Serratia spp 1.7%. All the enterococci isolates were multiply antibiotic resistant, and 42.9% were vancomycin-resistant enterococci (VRE) with the VRE strains showing resistance to wider range of antibiotics than the vancomycin-sensitive strains. Other Gram-positive and Gram negative bacterial isolates also demonstrated multiple resistance to all commonly available antibiotics in this community except E. coli and Pseudomonas spp which were relatively sensitive to ciprofloxacin and ceftazidime. This limited study demonstrated a high prevalence rate of multiple antibiotic resistant enterococci infections among hospitalized patients in this environment. There is need for systematic surveillance of hospitals for enterococci infections; prudent use and rational prescription of antibiotics and stringent measures to reduce the prevalence rate by health education on infection control measures such as isolation, cleaning, disinfection and sterilization.