Positive blood cultures for coagulase-negative staphylococci in neonates: does highly selective vancomycin usage affect outcome?

Late onset sepsis: comparison between coagulase-negative staphylococci and other bacteria in the neonatal intensive care unit

OBJECTIVE

To compare demographic and clinical features of neonates with late-onset sepsis due to coagulase-negative-staphylococcus with those due to other bacterial pathogens.

STUDY DESIGN

Retrospective, population-based cohort study. Data on infants less than 90 days old diagnosed with late-onset bacterial sepsis in the neonatal intensive care unit were reviewed. Univariable and multivariable analysis were performed.

RESULTS

Two hundred and sixteen sepsis episodes were identified: coagulase-negative-staphylococcus caused 113 (52.3%) and other pathogen 103 (47.7%). Patients with coagulase-negative-staphylococcus sepsis had lower gestational age and younger age at onset, higher rates of parenteral nutrition exposure and normal temperature, lower rates of necrotizing enterocolitis, meningitis and neutropenia than patients with sepsis caused by other pathogens. In multivariable analysis, parenteral nutrition was the only independent risk factor for coagulase-negative-staphylococcus sepsis (odds ratio: 3.5, 95% confidence interval: 1.4-8.6).

CONCLUSIONS

Initial empiric treatment for suspected sepsis should be targeted for other pathogens than coagulase-negative-staphylococci and vancomycin treatment should be reserved for infants with specific risk factors and according to local antimicrobial susceptibility.

Morbidity and mortality of coagulase-negative staphylococcal sepsis in very-low-birth-weight infants

BACKGROUND

Coagulase-negative staphylococci (CoNS) are the most common cause of late-onset sepsis in the neonatal intensive care unit (NICU) and usually require vancomycin treatment. Our objective was to determine whether CoNS are associated with neonatal morbidity and mortality.

METHODS

This was a retrospective cohort study of very-low-birth-weight (VLBW, ≤ 1500 g) infants from 1989 to 2015. Exclusion criteria were major congenital anomaly or death within 72 h. CoNS was considered a pathogen if recovered from ≥ 2 cultures, or 1 culture if treated for ≥ 5 days and signs of sepsis were present. Logistic regression was used to examine factors associated with morbidity and mortality.

RESULTS

Of 2242 VLBW infants, 285 (12.7%) had late-onset sepsis. CoNS (125, 44%), Staphylococcus aureus (52, 18%), and Escherichia coli (36, 13%) were the most commonly recovered organisms. In multivariate analysis, CoNS sepsis was not associated with mortality [OR 0.6 (95% CI 0.2-2.6)), but sepsis with other organisms was [OR 4.5 (95% CI 2.6-8.0)]. CoNS sepsis was associated with longer hospitalization but not risk for bronchopulmonary dysplasia, intraventricular hemorrhage, or retinopathy of prematurity.

CONCLUSION

CoNS sepsis was not associated with mortality or morbidities other than length of stay. These findings support vancomycin-reduction strategies in the NICU.

Empiric antibiotic regimens for neonatal sepsis in Australian and New Zealand neonatal intensive care units

AIM

Neonatal sepsis remains an important cause of morbidity and mortality, and requires prompt empiric treatment. However, only a minority of babies who receive antibiotics for suspected sepsis have an infection. Antimicrobial exposure in infancy has important short- and long-term consequences. There is no consensus regarding empirical antimicrobial regimens.

METHODS

The study included a survey of empiric antimicrobial regimens in all tertiary neonatal intensive care units in Australia and New Zealand in 2013-2014.

RESULTS

All 27 units responded. For early-onset sepsis, all units used a combination of gentamicin with either penicillin or ampicillin. For late-onset sepsis, the frequency of units using empiric vancomycin (41%) versus empiric flucloxacillin (48%) was similar. Gestational age or the presence of a central venous catheter had little influence on using vancomycin instead of flucloxacillin. For late-onset sepsis with meningitis there was marked variation in antimicrobial combinations, with 15 different regimens described. A total of 93% used a cefotaxime-based regimen, either as monotherapy (22%) or combined with a second (22%) or third (48%) agent. For suspected necrotising enterocolitis, 89% used an aminoglycoside, metronidazole and a penicillin. Historical outbreaks of multi-resistant organisms exerted long-term influence over regimen choice.

CONCLUSIONS

There was limited use of broad-spectrum agents such as carbapenems or third-generation cephalosporins. In this region with low methicillin-resistant Staphylococcus aureus prevalence, empiric vancomycin use was common, selected for activity against coagulase-negative staphylococci. Empiric vancomycin is rarely necessary because coagulase-negative staphylococci are often contaminants and sepsis is rarely fulminant, occurring almost exclusively in extremely low birthweight infants. Implementation of appropriate, local antimicrobial policies is crucial to minimise antimicrobial exposure in this vulnerable population and halt the development of antimicrobial resistance.

Understanding Bacterial Isolates in Blood Culture and Approaches Used to Define Bacteria as Contaminants: A Literature Review

BACKGROUND

Interpretation of blood culture isolates is challenging due to a lack of standard methodologies for identifying contaminants. This problem becomes more complex when the specimens are from sick young infants, as a wide range of bacteria can cause illness among this group.

METHODS

We used 43 key words to find articles published between 1970 and 2011 on blood culture isolates and possible contaminants in the PubMed database. Experts were also consulted to obtain other relevant articles. Selection of articles followed systematic methods considering opinions from more than 1 reviewer.

RESULTS

After reviewing the titles of 3869 articles extracted from the database, we found 307 relevant to our objective. Based on the abstracts, 42 articles were selected for the literature review. In addition, we included 7 more articles based on cross-references and expert advice. The most common methods for differentiating blood culture isolates were multiple blood cultures from the same subject, antibiograms and molecular testing. Streptococcus pneumoniae, Hemophilus influenzae, Neisseria meningitidis and group A and B streptococcus were always considered as pathogens, whereas Bacillus sp., Diphtheroids, Propionibacterium and Micrococcus were commonly regarded as contaminants. Coagulase-negative staphylococci were the most frequent isolates and usually reported as contaminants unless the patient had a specific condition, such as long-term hospitalization or use of invasive devices (catheters).

CONCLUSIONS

Inaccurate interpretation of blood culture may falsely guide treatment and also has long-term policy implications. The combination of clinical and microbiological knowledge, patient's clinical history and laboratory findings are essential for appropriate interpretation of blood culture.

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

OBJECTIVE

To characterize true coagulase-negative Staphylococcus (CoNS) infections in infants receiving neonatal intensive care.

STUDY DESIGN

Retrospective cohort study of neonatal intensive care unit (NICU) infants with clinical sepsis and CoNS isolated from ≥ 2 blood cultures (BCs) or one BC and a sterile site (proved infection) or CoNS isolated from one BC and deemed significant after blinded data review (probable infection).

RESULT

In all, 98% of 40 proved and 96% of 55 probable infections occurred in infants with birth weight (BW) <2000 g and gestation <34 weeks. Total central lines (CLs) placed, but not CL duration or presence in situ, predicted proved (odds ratio (OR) 3.5, 95% confidence interval (CI) 1.4 to 8.3; P=0.005) and probable infection (OR 2.7, 95% CI 1.3 to 5.6; P=0.007) by multivariate analysis as did lethargy and gastric residuals.

CONCLUSION

True CoNS infection is unlikely in infants with BW >2000 g and gestation >34 weeks. Total CL required for care, lethargy and gastric residuals predicted true CoNS infection.

Choice of antibiotics in late neonatal sepsis in the extremely low birth weight infant

OBJECTIVE

To review the choice of antibiotics in treating suspected late neonatal sepsis in infants weighing 1000 g or less in a neonatal intensive care unit.

METHODS

Retrospective review of medical records.

RESULTS

Ninety-six infants weighing 1000 g or less were admitted to the neonatal intensive care unit during the study period. Sixty-two infants survived beyond four days of life and had at least one sepsis workup done to exclude late neonatal infection. Of the 62 study patients, 42 (68%) were started on ampicillin and netilmicin (A/N) and 20 (32%) were started on vancomycin and ceftizoxime (V/C) as the antibiotics of choice, pending culture results. Of the patients started on A/N, 17 of 42 had a positive blood culture compared with 11 of 20 on V/C (40% versus 55%, P=0.40). The mean (+/-SD) birth weight of infants started on A/N was 793+/-133 g compared with a mean of 728+/-153 g in the group that received V/C (P=0.09). Seven patients died in the A/N group compared with three in the V/C group (16.7% versus 15%, P=0.84). In addition to the sepsis episode studied, before they were discharged from hospital, 21 of 42 (50%) infants in the A/N group had further workups for suspected sepsis, compared with 16 of 20 (80%) (P=0.048) infants initially given V/C.

CONCLUSIONS

Ampicillin and netilmicin is a safe antibiotic combination for neonates suspected of late sepsis. This, in turn, may be important in reducing vancomycin overuse and the potential for bacterial resistance to this antimicrobial agent.

The use of piperacillin/tazobactam (in association with amikacin) in neonatal sepsis: efficacy and safety data

Piperacillin/tazobactam (P/T) has been used in NICU since 1999 as part of the empirical treatment for presumed sepsis. We studied the microbiological and clinical efficacy and safety of P/T use in newborns with sepsis, using a retrospective analysis of medical records of all newborns treated with P/T (in association with amikacin) during 1999-2003. P/T plus amikacin was used for 353 episodes of presumed sepsis occurring in 252 newborns: 105 episodes occurred in 100 newborns treated for 5-14 d while in 248 (70%) episodes the treatment was discontinued after 2-3 d. 123 pathogens were isolated from the blood cultures (40 in the 5-14 d group and 83 in those treated for 2-3 d only). There were 56 Gram-negative, 55 Gram-positive and 12 Candida spp. isolates. Klebsiella spp. (40%) and E. coli (30%) were the most commonly isolated Gram-negative pathogens; coagulase-negative Staphylococcus (CONS) represented 95% of the Gram-positive pathogens isolated. Pathogen eradication was achieved within 48-72 h of therapy in 93% Gram-negative organisms. There were no clinical, laboratory or cranial ultrasound adverse effects associated with P/T use. We conclude that P/T in association with amikacin is microbiologically and clinically efficacious and safe in the treatment of sepsis in newborns.

Persistent bacteremia and severe thrombocytopenia caused by coagulase-negative Staphylococcus in a neonatal intensive care unit

OBJECTIVE

Coagulase-negative Staphylococcus (CoNS) is the most frequent cause of late-onset sepsis in NICUs, but mortality is rare and morbidity is unusual. We report a new syndrome of CoNS sepsis characterized by significant morbidity and persistent bacteremia despite aggressive antibiotic therapy and no identified focus of infection.

METHODS

We conducted a retrospective review of infants in the NICU with CoNS bacteremia between 2000 and 2002. Statistical analysis included an initial exploratory analysis followed by logistic regression. Microbiological identification of all isolates and molecular typing were performed.

RESULTS

Thirty-one neonates with persistent CoNS bacteremia were compared with 60 randomly selected neonates from a group of 140 with nonpersistent CoNS bacteremia. The clinical manifestations at presentation, gestational ages, and birth weights were similar in the 2 groups. Thrombocytopenia was present in 26 (84%) neonates with persistent CoNS bacteremia but only in 8 (13%) neonates in the nonpersistent group. Central venous catheterization increased the risk for persistent CoNS bacteremia, but 42% of the persistent group was never catheterized. Staphylococcus epidermidis was the most common isolate in both groups. Molecular typing failed to identify a predominant clone.

CONCLUSIONS

The syndrome of persistent CoNS septicemia is remarkable for thrombocytopenia and persistence in the absence of central venous catheterization. Clinical manifestations at presentation and demographic characteristics did not discriminate between the persistent and nonpersistent groups. We did not identify the emergence of a particularly virulent clone, but it is possible that some strains of CoNS have acquired the capacity to persist under different conditions.

Cloxacillin versus vancomycin for presumed late-onset sepsis in the Neonatal Intensive Care Unit and the impact upon outcome of coagulase negative staphylococcal bacteremia: a retrospective cohort study

Background

Coagulase negative staphylococcus (CONS) is the main cause of late-onset sepsis in Neonatal Intensive Care Units (NICU). Although CONS rarely causes fulminant sepsis, vancomycin is frequently used as empiric therapy. Indiscriminate use of vancomycin has been linked to the emergence of vancomycin resistant organisms. The objective of this study was to compare duration of CONS sepsis and mortality before and after implementation of a policy of selective vancomycin use and compare use of vancomycin between the 2 time periods.

Methods

A retrospective study was conducted of infants ≥4 days old, experiencing signs of sepsis with a first positive blood culture for CONS, during two 12-month periods. Late-onset sepsis was treated empirically with vancomycin and gentamicin during period 1, and cloxacillin and gentamicin during period 2. The confidence interval method was used to assess non-inferiority of the outcomes between the two study groups.

Results

There were 45 episodes of CONS sepsis during period 1 and 37 during period 2. Duration of sepsis was similar between periods (hazard ratio of 1.00, 95%CI: 0.64, 1.57). One death during period 2 was possibly related to CONS sepsis versus none in period 1. Vancomycin was used in 97.8% of episodes in period 1 versus 81.1% of episodes in period 2.

Conclusion

Although we failed to show non-inferiority of duration of sepsis in the cloxacillin and gentamicin group compared to the vancomycin and gentamicin group, duration of sepsis was clinically similar. Restricting vancomycin for confirmed cases of CONS sepsis resistant to oxacillin appears effective and safe, and significantly reduces vancomycin use in the NICU.

Acquisition nosocomiale de bactéries multirésistantes dans un service de néonatologie : étude prospective et analyse des facteurs de risque

A systematic analysis of weekly nasal and rectal swabs was carried out in a neonatal unit in order to detect colonization with multiresistant bacteria (MRB).

PATIENTS AND METHODS

During a 6-month period, rectal and nasal samples were taken in 187 consecutively hospitalized newborns, the day of the admission (day 0) and every week until discharge, in order to detect MRB, mainly methicillin-resistant coagulase negative staphylococci (MRCoNS), Staphylococcus aureus and multi-resistant Gram-negative bacilli.

RESULTS

Among 187 infants, 50 were already colonized at entrance and excluded from the study. In others, 49 (35%) were colonized by at least one MRB, with a total of 71 strains isolated. The most frequent was MRCoNS, especially Staphylococcus epidermidis (66.1%). Gram-negative bacilli accounted for 9.8%. Colonization began earlier with MRCoNS than with Gram-negative bacilli, 7.8 +/- 6 vs. 15.5 +/- 16 days, P=0.004, and finished earlier 22.7 +/- 15 vs. 38.5 +/- 16 days, P=0.03. Colonized children exhibited by univariate analysis a lower birth weight, more frequent parenteral nutrition or previous hospitalization in a neonatal unit and a younger age at admission. Odds ratio for colonization were 4.06 for prematurity and 43.83 for a previous hospitalization. MRCoNS at days 15 (P <0.05) and 22 (P <0.05) were correlated with the empiric use of antibiotics. No nosocomial infection occurred during the study.

CONCLUSION

A high rate of newborns were colonized with MRB in our unit, especially MRCoNS, acquired earlier than Gram-negative bacilli, with a favoring action of empiric antibiotherapy.

Features of invasive staphylococcal disease in neonates

OBJECTIVE

Most clinical descriptions of invasive staphylococcal disease (ISD) in neonates date from before the mid-1980s, when neonatal viability and intensive care differed substantially from current standards. We aimed to describe the contemporary incidence, clinical features, and outcome of infants with ISD in a neonatal intensive care unit.

METHODS

A retrospective cohort study was conducted of infants who had ISD and were in the neonatal intensive care unit of the Woman's Hospital of Texas, Houston, from January 2000 to June 2002. Confirmed ISD was defined as clinical sepsis and Staphylococcus aureus (SA) isolated from > or =1 blood culture (BC) or a sterile body site excluding urine or coagulase-negative staphylococci (CoNS) isolated from > or =2 BC or from 1 BC and a sterile body site. Probable ISD was defined as CoNS isolated from 1 BC or a sterile body site for which clinical and laboratory data review by 3 infectious disease specialists indicated that antimicrobial treatment was appropriate. Confirmed and combined confirmed plus probable cases were analyzed.

RESULTS

A total of 149 episodes (83 confirmed [39 SA, 44 CoNS], 66 probable) in 137 infants (mean gestational age [GA]: 27.6 weeks [22.4-36.4]; mean birth weight: 981 g [350-2995]) were reviewed. Four (3%) infants had early-onset infection (2 SA, 2 CoNS). Median age at infection onset was similar (17 days SA; 18 days CoNS). Intravascular catheters (IVC) were in situ in a minority of infants with ISD episodes (38% SA, 43% CoNS). CoNS more than SA infections were associated with very low birth weight (<1500 g), lower GA, a history of more IVCs and concurrent total parenteral nutrition, but IVC and parenteral nutrition days were similar. By multivariate analysis correcting for birth weight and complications of prematurity, hypoxia at the time of sepsis evaluation was significantly associated with CoNS and hypotension with SA infections; other clinical features were similar. Methicillin-resistant SA caused 8% of SA infections. Among bacteremic infants, SA more frequently than CoNS involved > or =2 sites. Overall, SA had more focal complications (primarily bone and joint) than CoNS, resulting in a 2- to 3-fold higher SA-associated morbidity rate. Mortality directly attributable to either organism was similar (5% SA; 5% confirmed, 3% confirmed/probable CoNS).

CONCLUSION

CoNS ISD occurred in smaller, more premature infants than SA and was IVC associated in a minority of cases. Hypoxia and hypotension were the only presenting features that differentiated CoNS and SA. SA-associated morbidity was substantial, but SA infection carried no greater risk of death (5%) than CoNS.

Clinical microbiology of bacterial and fungal sepsis in very-low-birth-weight infants

Twenty percent of very-low-birth-weight (<1500 g) preterm infants experience a serious systemic infection, and despite advances in neonatal intensive care and antimicrobials, mortality is as much as threefold higher for these infants who develop sepsis than their counterparts without sepsis during their hospitalization. Outcomes may be improved by preventative strategies, earlier and accurate diagnosis, and adjunct therapies to combat infection and protect the vulnerable preterm infant during an infection. Earlier diagnosis on the basis of factors such as abnormal heart rate characteristics may offer the ability to initiate treatment prior to the onset of clinical symptoms. Molecular and adjunctive diagnostics may also aid in diagnosing invasive infection when clinical symptoms indicate infection but no organisms are isolated in culture. Due to the high morbidity and mortality, preventative and adjunctive therapies are needed. Prophylaxis has been effective in preventing early-onset group B streptococcal sepsis and late-onset Candida sepsis. Future research in prophylaxis using active and passive immunization strategies offers prevention without the risk of resistance to antimicrobials. Identification of the differences in neonatal intensive care units with low and high infection rates and implementation of infection control measures remain paramount in each neonatal intensive care unit caring for preterm infants.

Vancomycin

This review describes the use of vancomycin in neonates over the last three decades. Given the relation of late-onset neonatal septicaemia to outcome and the increase in coagulase-negative staphylococcal infection as causative organism, vancomycin remains an important antibacterial in the neonatal intensive care unit. The pharmacokinetic behaviour of vancomycin in neonates can be adequately described by a one- or two-compartment model and is mainly determined by postconceptional age and renal function. In neonates, a patent ductus arteriosus as well as treatment with indomethacin or extracorporeal membrane oxygenation (ECMO) leads to an increase in volume of distribution and a decrease in clearance. Microbiological studies in vitro have shown that an increase in vancomycin concentrations above the minimum inhibitory concentration does not result in more effective killing. The microbiological and clinical efficacy of vancomycin in neonates has only been studied explicitly in a restricted number of patients. There are no definitive data relating serum concentrations to effect in this patient group. Vancomycin-related nephrotoxicity and ototoxicity in neonates is rare, and no clear relation to serum concentrations has been demonstrated. Based on the pharmacokinetic profile of vancomycin in neonates, several administration regimens have been constructed. Recent guidelines have suggested that dosage can be independent of gestational age or postconceptional age in neonates without renal failure. In patients with renal failure, therapy can be adequately tailored by using a regimen based on serum creatinine. The usefulness of routine monitoring of peak serum concentrations is doubtful based on the current literature. Recent research demonstrates a shift towards taking only routine trough serum concentrations in order to optimise efficacy. Patients with renal failure and other special subpopulations, such as patients exposed to ECMO or indomethacin, need to be monitored more closely.

Nosocomial coagulase negative staphylococcal (CoNS) catheter-related sepsis in preterm infants: definition, diagnosis, prophylaxis, and prevention

Nosocomial infections with coagulase negative staphylococcus (CoNS) are a frequent and significant cause of morbidity in the preterm infant. Infections diagnosed after the first 72 hours of life are arbitrarily deemed to be "nosocomial." There are many difficulties encountered in efforts to evaluate and compare nosocomial sepsis in the NICU. An issue of primary concern is the lack of uniformity in the definition of sepsis in the NICU. Based on the frequency of positive blood cultures in infants less than 1000 g, it appears reasonable to evaluate methods for the prevention of nosocomial sepsis. These include prophylactic antibiotic administration, antiseptic impregnated catheters, and the use of an antibiotic lock technique.

Fulminant late-onset sepsis in a neonatal intensive care unit, 1988-1997, and the impact of avoiding empiric vancomycin therapy

OBJECTIVE

To determine the pathogens associated with fulminant (lethal within 48 hours) late-onset sepsis (occurring after 3 days of age) in a neonatal intensive care unit (NICU) and the frequency of fulminant late-onset sepsis for the most common pathogens.

METHODS

A retrospective study was conducted of sepsis in infants in a NICU over a 10-year period (1988-1997).

RESULTS

There were 825 episodes of late-onset sepsis occurring in 536 infants. Thirty-four of 49 (69%; 95% confidence interval [CI]: 55%-82%) cases of fulminant late-onset sepsis were caused by Gram-negative organisms, including Pseudomonas sp., 20 (42%); Escherichia coli, 5 (10%); Enterobacter sp., 4 (8%); and Klebsiella sp., 4 (8%). The frequency of fulminant sepsis was highest for Pseudomonas sp., 20 of 36 (56%; 95% CI: 38%-72%) and lowest for coagulase-negative staphylococci, 4 of 277 (1%; 95%CI: 0%-4%). The very low frequency of fulminant sepsis caused by coagulase-negative staphylococci did not increase during the period when oxacillin was used instead of vancomycin as the empiric antibiotic for Gram-positive organisms.

CONCLUSIONS

These data suggest that empiric antibiotics selected for treatment of suspected sepsis in infants >3 days old need to effectively treat Gram-negative pathogens, particularly Pseudomonas sp., because these organisms, although less frequent, are strongly associated with fulminant late-onset sepsis in the NICU. Avoiding empiric vancomycin therapy seemed to be a reasonable approach to late-onset sepsis, because of the very low frequency of fulminant sepsis caused by coagulase-negative staphylococci.

Vancomycin for prophylaxis against sepsis in preterm neonates

BACKGROUND

Nosocomial, late onset sepsis occurs in up to 50% of infants of less than 1000gm at birth. The commonest organism isolated is coagulase negative staphylococcus (CoNS). A number of studies have evaluated the efficacy or prophylactic low dose vancomycin given either as a continuous infusion added to the infant's hyperalimentation fluid or by intermittent intravenous administration and these studies in very low birth weight infants are the subject of this review.

OBJECTIVES

To evaluate the safety and efficacy of vancomycin prophylaxis for the prevention of late-onset sepsis, coagulase negative staphylococcal sepsis, mortality, and effects on length of stay, total vancomycin exposure, evidence of vancomycin toxicity, and the development of vancomycin resistant organisms in the preterm neonate.

SEARCH STRATEGY

Searches were made of Medline, (MeSH terms: Vancomycin and Sepsis; limits: age groups, newborn infants), HealthStar and EMBase, electronic abstracts, personal files and conference proceedings.

SELECTION CRITERIA

Randomized controlled trials which compared the incidence of sepsis and mortality in preterm neonates receiving vancomycin prophylaxis versus a control group receiving no prophylaxis.

DATA COLLECTION AND ANALYSIS

Data regarding clinical outcomes including the overall incidence of sepsis, the incidence of coagulase negative staphylococcal sepsis, mortality, length of stay, total vancomycin exposure, evidence of vancomycin toxicity, and the development of vancomycin resistant organisms were excerpted from previous clinical trials. Data analysis was done in accordance with the standards of the Cochrane Neonatal Review Group.

MAIN RESULTS

The administration of prophylactic vancomycin reduced the incidence of both total neonatal nosocomial sepsis and coagulase negative staphylococcal sepsis in eligible preterm infants. Mortality, length of stay, and evidence of vancomycin toxicity were not significantly different between the two groups. There was insufficient evidence to ascertain the risks of development of vancomycin resistant organisms in the nurseries involved in these trials.

REVIEWER'S CONCLUSIONS

The use of prophylactic vancomycin in low doses reduces the incidence of nosocomial sepsis in the neonate. The methodologies of these studies may have contributed to the low rate of sepsis in the treated groups, as the blood cultures drawn from central lines may have failed to grow due to the low levels of vancomycin in the infusate. Although there is a theoretical concern regarding the development of resistant organisms with the administration of prophylactic antibiotic, there is insufficient evidence to ascertain the risks of development of vancomycin resistant organisms. Few clinically important benefits have been demonstrated for very low birth weight infants treated with prophylactic vancomycin. It therefore appears that routine prophylaxis with vancomycin should not be undertaken at present.