Persistent Isolation of Multidrug Resistant Gram-Negative Bacteria From Mechanically Ventilated Newborns in a Newly Established Neonatal Intensive Care Unit

Ventilator-associated pneumonia is the second most common nosocomial infection in neonatal intensive care unit (NICU) patients. The recent trend signifies multidrug resistant (MDR) Acinetobacter baumannii and Pseudomonas aeruginosa as the most frequent causative agents in these cases.
The aim of this research was to study the trends in the isolation of MDR pathogens from a newly constructed NICU.
A retrospective analysis of six months data on isolation of MDR pathogens from newborns on mechanical ventilation in a newly established NICU was done.
Out of seven, MDR Acinetobacter baumannii was isolated from four (57.14%) newborns on mechanical ventilation. The strain was sensitive only to polymyxin B and colistin and was isolated repeatedly from the initial three samples collected at an interval of two to three days. In one case, Pseudomonas aeruginosa was also isolated in association with Acinetobacter with same sensitivity pattern. While expecting recovery from illness in two babies, sudden change in the type of microbial flora was noticed in the samples collected on the 4th instance. This time, the initial polymyxin-sensitive organisms were replaced by intrinsically polymyxin resistant organisms like Serratia species and Burkholderia cepacia.
Repeated isolation of MDR Acinetobacter baumannii along with other resistant phenotypes of gram-negative bacteria is a cause of concern for any newly established NICU setup. Long-term use of reserved antibiotics leads to selection pressure, resulting in establishment of the relatively less common environmental opportunists as new, more troublesome pathogens. It may further complicate the treatment decisions and lengthen the hospital stay and associated morbidity.