Persistent coagulase-negative staphylococci bacteremia in very-low-birth-weight infants

Abstract

This study sought to expand current knowledge on the clinical and epidemiological characteristics of persistent coagulase-negative Staphylococcus (CoNS) bacteremia in very-low-birth-weight (VLBW) infants. Background and disease-related data were collected prospectively on 143 VLBW infants diagnosed with CoNS bacteremia at a pediatric tertiary medical center in 1995-2003. Findings were compared between those with persistent (positive blood cultures for >72 h under appropriate treatment ) and nonpersistent disease. Fifty-eight infants (40.6%) were found to have persistent bacteremia. There were no between-group differences in maternal characteristics, mode of delivery, newborn characteristics, dwell time of central venous and umbilical catheters, complications of prematurity, or mean hospital stay. The persistent bacteremia group had significantly higher rates of hypothermia at presentation (37.9% vs. 17.6%, p < 0.04), creatinine >1.2 mg% on treatment day 7 (13.7% vs. 2.4%, p < 0.02; transient phenomenon), and endocarditis (p < 0.03); one infant had an aortic thrombus. Predominantly breast-fed infants had a higher rate of negative cultures within 72 h of appropriate treatment than predominantly formula-fed infants (60% vs. 19%, p < 0.02). In conclusion, persistence of CoNS bacteremia is common in VLBW infants. Endocarditis should be excluded in all infants with persistent disease. Breast-feeding is associated with a shorter disease duration.

Incidence, Clinical Characteristics and Attributable Mortality of Persistent Bloodstream Infection in the Neonatal Intensive Care Unit

“…The incidence of persistent BSI reported by previous studies was much higher than our series. For example, 16% to 40.5% of CoNS bacteremia were reported to be persistent in previous studies [ 7 , 9 , 11 , 27 ]. However, their definitions of persistent BSI were different from ours: Chapman et al [ 7 ] applied recovery of CoNS >24 hours, Linder et al [ 27 ] defined recovery of CoNS >72 hours after adequate antibiotic therapy was begun and Patrick et al [ 11 ] used persistent bacteremia for positive blood culture of more than 6 days.…”

Distinguishing true coagulase-negative Staphylococcus infections from contaminants in the neonatal intensive care unit

“…14 One noteworthy finding was that despite the perception of CoNS bloodstream infection as 'benign' 3,7,8,27,28 these infections have potential in the NICU infant to cause profound illness and even death. 6,10 Not only did some CoNS-infected infants present with findings associated with severe sepsis, but 67% of those in whom the diagnosis was proved had involvement of multiple body sites, 25% required surgical intervention (predominantly for skin and soft tissue complications) and 5% had CoNS-attributable mortality. Prolonged antibiotic courses were needed for endocarditis (8%) and for the rare bone and joint complications more typically associated with Staphylococcus aureus.…”

“…1,2 Case-fatality rates have varied according to neonatal characteristics and pathogen, ranging from 0 to 74% in contemporary series of neonatal sepsis. [3][4][5][6][7][8][9][10] The diagnosis of sepsis in the neonatal intensive care unit (NICU) setting is difficult as clinical features are non-specific, but sepsis can rapidly progress and even be fatal before the infecting pathogen has been identified. 3,4,8,9 Coagulase-negative staphylococci (CoNS) are commensal skin flora but these organisms account for up to one-half of reported bloodstream infections in very low birth weight (<1500 g) infants.…”

Coagulase-Negative Staphylococci

“…While in several studies CoNS-related mortality was rather rare (168,169), other investigations indicated that the mortality rate attributable to CoNS was comparable to that of S. aureus and that persistent bacteremia-in the absence of central venous catheterization-and significant morbidity, despite aggressive antibiotic therapy, may still occur (78,163,170,171). In neonates requiring intensive care, biofilm production, independently of the presence of the ica operon, was shown to be the most significant risk factor for persistent, lateonset CoNS bacteremia (78).…”