Neonatal bacteremia: patterns of antibiotic resistance.
OBJECTIVE
To determine the incidence and evaluate the antimicrobial-susceptibility patterns of bacterial infections in our neonatal units.


METHODS
Retrospective surveillance study.


METHODS
The neonatal units of the Hadassah University Hospitals, Jerusalem, Israel.


METHODS
All newborns admitted from January 1994 through February 1999.


METHODS
The records of all patients with positive blood and cerebrospinal fluid cultures were reviewed. Bacteremia was considered early-onset (vertical) when occurring within the first 72 hours of life and late-onset (nosocomial) when occurring later. The prevalence and antibiotic-resistance patterns of vertically transmitted and nosocomially acquired strains were compared and studied over time.


RESULTS
219 of 35,691 newborn infants had at least one episode of bacteremia (6.13/1,000 live births). There were 305 identified organisms, of which 21% (1.29/1,000 live births) were considered vertically transmitted and 79% nosocomially acquired. The most common organism causing early-onset disease (29.2%) was group B streptococcus (0.38/1,000 live births), whereas coagulase-negative staphylococci (51%) were the most prevalent in late-onset disease. All gram-positive bacteria were susceptible to vancomycin. Most gram-positive organisms other than staphylococci were susceptible to ampicillin. Gram-negative organisms represented 31% of all isolates. Generally, there was a trend of increasing resistance to commonly used antibiotics among nosocomially acquired gram-negative organisms, compared to those vertically transmitted, with statistically significant differences for ampicillin and mezlocillin (P<.05 and P<.01, respectively). Over the years, a trend toward an increasing resistance to antibiotics was observed among gram-negative organisms.


CONCLUSIONS
The trend of increasing bacterial resistance to commonly used antibiotics necessitates the implementation of a rational empirical treatment strategy, based on local susceptibility data, reserving certain agents for emerging resistant pathogens.
Bromiker
R
R
Department of Neonatology, Hadassah University Hospitals, Jerusalem, Israel.
Arad
I
I
Peleg
O
O
Preminger
A
A
Engelhard
D
D
D003428:Cross Infection / Q000635:transmission; D024881:Drug Resistance, Bacterial; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D018805:Sepsis / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology