Emergence of multi-drug-resistant Acinetobacter anitratus species in neonatal and paediatric intensive care units in a developing country: concern about antimicrobial policies.

Antimicrobial abuse is a serious risk factor for the emergence of multi-drug-resistant (MDR) pathogens. We report on the emergence of multi-drug-resistant Acinetobacter anitratus species over two 8-week periods in 1999 in the neonatal and paediatric intensive care units (NICU and PICU) of King Edward VII Hospital, Durban, South Africa. The source, transmission dynamics, microbiological evaluations, antibiotic utilization patterns and outcome were evaluated. MDR Acinetobacter anitratus was isolated from different body sites in 23 infants less than 2 months of age, 18 in the PICU and five in the NICU. The mortality was 56.5% and two survivors required re-admission. Ten of the 23 cases had entered the ICU with MDR Acinetobacter anitratus. Eleven of the study infants had received broad-spectrum antimicrobial agents before entering the ICU, while all infants with nosocomially acquired MDR Acinetobacter anitratus had received broad-spectrum antimicrobial agents. All the surgical cases with MDR Acinetobacter anitratus died. Microbiological data from both ICUs for 1999 indicated that gram-negative bacteria accounted for two-thirds of isolates, Acinetobacter anitratus and Klebsiella pneumoniae accounting for 33% and 27% of the isolates, respectively. Only 53% and 57% of all Acinetobacter spp isolates were susceptible to piperacillin/tazobactam and carbepenems, respectively. MDR Acinetobacter anitratus is an emerging problem to which antimicrobial abuse contributes.