Outbreak of Acinetobacter infection in extremely low birth weight neonates.
OBJECTIVE
We describe the first outbreak of multiple drug-resistant Acinetobacter baumannii (MDR-Ab) in a neonatal intensive care unit in the United States.


METHODS
MDR-Ab was identified in the blood of a 24-week gestation, 7-day-old extremely low birth weight neonate. Multiple samplings of surveillance surface cultures were performed on exposed and nonexposed neonates. Enhanced infection control measures were implemented. Pulsed-field gel electrophoresis was performed to determine the genetic relatedness of the MDR-Ab isolates. Medical records were reviewed for all exposed patients.


RESULTS
MDR-Ab was recovered from 6 additional neonates. Of these 7 MDR-Ab (index + 6) neonates, 4 died, 3 of whom had positive blood cultures. All affected neonates were born between 23 to 26 weeks gestational age, and were <7 days postnatal age and <750 g (430-720) at the time of exposure. All were housed within the same room as the index case. None of the other 5 exposed neonates older than postnatal day 7 or weighing >750 g at birth were affected. No additional cases occurred outside the original room. Pulsed-field gel electrophoresis was consistent with a clonal origin, identical to MDR-Ab recovered from the referring hospital.


CONCLUSIONS
This MDR-Ab outbreak was rapidly controlled with enhanced infection control measures and was novel in that it affected only <750 g neonates, at < or =26 weeks gestational age, and < or =7 days postnatal age at the time of exposure, suggesting that invasive Ab has a special affinity for damaged or nonkeratinized immature skin in developmentally immature immunologic hosts.
Simmonds
Aryeh
A
Division of Neonatology, Department of Pediatrics, Winthrop University Hospital, Mineola, NY 11501, USA. asimmonds@winthrop.org
Munoz
Jose
J
Aguero-Rosenfeld
Maria
M
Carbonaro
Carol
C
Montecalvo
Marisa
M
Clones
Barbara
B
LaGamma
Edmund F
EF
D000151:Acinetobacter Infections / Q000453:epidemiology* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D000328:Adult; D004196:Disease Outbreaks; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006801:Humans; D052577:Infant, Extremely Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control; D007363:Intensive Care Units, Neonatal; D008297:Male