ANTIBIOTIC SENSITIVITY PATTERNS AMONGST POST-MORTEM BACTERIAL ISOLATES FROM HIV-INFECTED PATIENTS IN WESTERN KENYA: A CROSS SECTIONAL DESCRIPTIVE STUDY

Background: In the sub-Saharan Africa, there are minimal data about the antibiotic sensitivity patterns of the common bacterial isolates from HIV-infected patients. We conducted an autopsy study to determine the antibiotic sensitivity patterns of the common bacterial isolates.

Methods: HIV-infected patients at Moi Teaching and Referral Hospital, Eldoret Kenya, who die while on antiretroviral therapy underwent autopsy. Bacterial cultures on selective media were taken from body fluids and tissues. For instance urine samples were cultured in cysteine lactose electrolyte deficient (CLED) agar; stool in Deoxycholate Citrate Agar (DCA) and Xylose lysine deoxycholate agar (XLD); all other samples, including blood, were cultured in Blood Agar and Mac Conkey. Isolates were stored at -18 to -25°C. They were then sub-cultured and a Gram stain performed to classify the pathogens as either Gram positive or negative. Isolates were then subjected to an automated identification and antibiotic sensitivity testing by Minimum Inhibitory Concentration using the Siemens Micro-scan Walkaway 40 plus model® and the Vitek® system.

Results: A total of 416 bacterial isolates were cultured from 202 (57.7%) of the 350 cadavers. The three most common pathogens isolated included E. coli (22.4%), Klebsiella pneumonia (10.8%) and Staphylococcus aureus (9.1%) E. coli isolates were highly resistant to ampicillin (97%), 3rd and 4th generation cephalosporins (50%) and gentamicin (40%). 36% of these isolates were Extended Spectrum Beta-Lactamase (ESBL)-producing. Klebsiella isolates showed high resistance to ampicillin (86%), ceftazidime (52%) and gentamicin (55%). An estimated 60% of S. aureus isolates were methicillin resistant Staphylococcus aureus (MRSA) and 13% were vancomycin resistant Staphylococcus aureus (VRSA). Enterococcus spp showed high level resistance to gentamicin- and streptomycin-high level synergy (>80%). An estimated 5% of the isolates were vancomycin resistant Enterococci (VRE).

Conclusion and Recommendation: Our data show that antibiotic-resistant bacterial pathogens colonize HIV-infected patients at the time of death. This study provides definitive evidence that MRSA, VRE and ESBL Gram-Negative-Rods are an emerging issue in our HIV-infected population.