Bacteriology of burns at the Queen Elizabeth Central Hospital, Blantyre, Malawi

A retrospective study to determine the bacterial profile and antibiotic susceptibility pattern of burn isolates at the Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi was undertaken. While a total of 1825 burn patients were admitted to the hospital over a 6-year period (January 1994 to December 1999) only 317 (17.4%) specimens selected from as many patients were processed. One hundred and seventy (170/53.6%) specimens yielded single while the rest (147/46.4%) had multiple isolates giving a total of 535 bacterial isolates. Of this number, 236 (44.1%) were Gram-negatives and 299 (55.9%), Gram-positives. Among the Gram-negatives, Pseudomonas aeruginosa, Proteus mirabilis, Coliforms/Escherichia coli and Klebsiella pneumoniae were the most common accounting for 94.1% while in the Gram-positive group, staphylococcal and streptococcal spp. predominated (100%). However, the three most common isolates were Staphylococcus aureus (37.6%), P. aeruginosa (22.4%) and beta-haemolytic streptococci (13.6%). While S. aureus and beta-haemolytic streptococci were most susceptible to penicillin (33.3 and 64.4% susceptibility, respectively), gentamycin appeared most effective against P. aeruginosa (53.3%). A general broad-spectrum resistance to panels of antibiotics used in the study was however observed among the bacterial isolates. From these results, S. aureus, P. aeruginosa, streptococcal spp., P. mirabilis, Coliforms and K. pneumoniae representing 96.4% of all isolates were the most common in the Burns Unit.