Laboratory information system for reporting antimicrobial resistant isolates from academic hospitals, South Africa

We aimed to evaluate the appropriateness of Digital Innovation South Africa (DISA)-based laboratory information system (LIS) for assessing the prevalence, patterns and trends of antimicrobial resistance, and associated demographic factors.

A retrospective analysis was conducted on routine data of blood culture isolates of Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. These isolates were collected by the National Health Laboratory Services between July 1, 2005 and December 31, 2009 at seven tertiary public hospitals. Factors associated with antimicrobial resistance were analysed using multivariate logistic regression.

Information on 9969 isolates was available, of which 3942 (39.5%), 4466 (44.8%) and 1561 (15.7%) were Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa, respectively. Reporting of resistance across antibiotics tested was highest in patient age group less than 5 years old. Methicillin resistant Staphylococcus aureus was 39% on average. There was a significant increasing trend of Klebsiella pneumoniae resistance to ciprofloxacin (32.6% to 64.9%, p < 0.001), cotrimoxazole (67.5% to 81.6%, p < 0.001) and cefotaxime-ceftriaxone (55.5% to 73.2%, p < 0.001) over the study period. Pseudomonas aeruginosa resistance to meropenem showed a significant increasing trend from 2006 (27.5%) to 2009 (53.9%) (p < 0.001). Age group < 5 years, female gender, hospital location, year of infection were significantly associated with antimicrobial resistance.

The percentages of antimicrobial resistance were high and showed a significant increasing trend among individual agents over the duration of the study e.g. ciprofloxacin, cotrimoxazole among others. Continued surveillance of antimicrobial resistance among bloodstream hospital-acquired infections should be strengthened.