Microbial isolates from clinical specimens of blood culture and their antimicrobial susceptibility profiles: Findings from an analysis of 3,255 blood culture specimens at a university teaching hospital in southern Nigeria

Authors:Godwin T. Jombo , Samuel Akpan , James Epoke, Priscilla Denen Akaa , Kumomo I. Eyong, Abraham N. Gyuse, Ezinwa N. Amefule, Oquong O. Uket
Int J Biol Med Res. 2010; 1(3): 66 - 70  |  PDF File

Abstract

The study was carried out to ascertain the pattern of antimicrobial distribution and their antibiotic susceptibility profile from blood culture samples. The study was retrospective in nature and carried out at University of Calabar Teaching Hospital (UCTH) Calabar; data generated from blood culture specimens over a five year period (Feb. 2004-Feb. 2009) was compiled, relevant information such as age, sex, organism recovered and antibiotic susceptibility patterns were obtained from patients records. Samples were collected, transported, stored and processed using standard laboratory procedures. Data obtained was analysed using Epi Info 6 statistical software. The incidence of positive blood culture was 6.2% (203/3,255); 7.1% (89/1,260) among males and 5.8% (111/1,910) among females with no significant age and gender differences (P> 0.05). Staphylococcus aureus 22.7%, Klebsiella spp. 20.2% and Escherichia coli 15.3% were the three most common bacterial isolates and Citrobacter/Enterobacter spp the least 4.4%. None of the antibiotics tested was 100% active against isolates of Staphylococcus aureus, coagulase negative Staphylococci, Proteus spp. and Salmonella typhi/paratyphi; majority of the bacterial agents, mostly nosocomial in origin, were resistant to at least four antibiotics. The most inactive antibiotics were: penicillin G, ampicillin, cloxacillin, amoxicillin, tetracycline and chloramphenicol (0-58.1% activity), and the most active were: Ofloxacin, ciprofloxacin, ceftazidime, cefuroxime, ceftriaxone, augmentin and colistin (42.9%-100% activity. Microorganisms causing blood infections are diverse with high resistance; hence, proper standards for infection control, antisepsis and disinfection should be stepped up in hospital environments in order to reduce the spread of the highly resistant bacteria.