Epidemic gram-negative bacteremia in a neonatal intensive care unit in Guatemala.
BACKGROUND
Nosocomial bloodstream infection is an important cause of morbidity and mortality among neonates. From September 1 through December 5, 1990 (epidemic period), gram-negative bacteremia developed in 26 neonates after their admission to the neonatal intensive care unit (NICU) of Hospital General, a 1000-bed public teaching hospital in Guatemala with a 16-bed NICU. Twenty-three of the 26 patients (88%) died.


METHODS
To determine risk factors for and modes of transmission of gram-negative bacteremia in the NICU, we conducted a cohort study of NICU patients who had at least one blood culture drawn at least 24 hours after admission to the NICU and performed a microbiologic investigation in the NICU.


RESULTS
The rate of gram-negative bacteremia was significantly higher among patients born at Hospital General, delivered by cesarian section, and exposed to selected intravenous medications and invasive procedures in the NICU during the 3 days before the referent blood culture was obtained. During the epidemic period, the hospital's chlorinated well-water system malfunctioned; chlorine levels were undetectable and tap water samples contained elevated microbial levels, including total and fecal coliform bacteria. Serratia marcescens was identified in 81% of case-patient blood cultures (13/16) available for testing and from 57% of NICU personnel handwashings (4/7). Most S. marcescens blood isolates were serotype O3:H12 (46%) or O14:H12 (31%) and were resistant to ampicillin (100%) and gentamicin (77%), the antimicrobials used routinely in the NICU.


CONCLUSIONS
We hypothesize that gram-negative bacteremia occurred after invasive procedures were performed on neonates whose skin became colonized through bathing or from hands of NICU personnel.
Pegues
D A
DA
Hospital Infections Program, CDC, Atlanta, GA 30333.
Arathoon
E G
EG
Samayoa
B
B
Del Valle
G T
GT
Anderson
R L
RL
Riddle
C F
CF
O'Hara
C M
CM
Miller
J M
JM
Hill
B C
BC
Highsmith
A K
AK
D016470:Bacteremia / Q000453:epidemiology* / Q000635:transmission; D015331:Cohort Studies; D003428:Cross Infection / Q000453:epidemiology* / Q000635:transmission; D036861:Delivery, Obstetric / Q000379:methods; D004196:Disease Outbreaks; D005260:Female; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000635:transmission; D006166:Guatemala / Q000453:epidemiology; D006235:Hand Disinfection; D006801:Humans; D007224:Infant Care; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D008297:Male; D010564:Personnel, Hospital; D011247:Pregnancy; D012307:Risk Factors; D014871:Water Microbiology