Selective decontamination with nystatin for control of a Candida outbreak in a neonatal intensive care unit

Increasing candidaemia incidence from 2004 to 2015 with a shift in epidemiology in patients preexposed to antifungals

Candidaemia is an important health problem in immunocompromised patients with an epidemiology varying with region, period and patient population involved. The occurrence of candidaemia and the associated species distribution over a 12-year period at a large tertiary care centre in Belgium were analysed. The trend in incidence in the intensive care units (ICUs) and non-ICUs was investigated as well as the influence of antifungal exposure on the species distribution. From 2004 until 2015, 865 candidaemia episodes occurred in 826 patients at the University Hospitals Leuven. Candida albicans (59%) remained the most important cause of candidaemia, followed by C. glabrata (22.4%) and C. parapsilosis (8%). The mean incidence in the whole hospital was 1.48 per 10 000 patient days (PD). The incidence in ICUs increased reaching up to 10.7 per 10 000 PD whereas in the non-ICUs, the incidence decreased. Prior exposure to fluconazole and echinocandins was associated with candidaemia caused by less susceptible species. Candidaemia incidence increased in the whole hospital, driven by ICUs. Surveillance of candidaemia epidemiology on a local scale is of high value to guide empirical treatment strategies.

Selective digestive decontamination in critically ill children: A survey of Canadian providers

BACKGROUND

Selective digestive decontamination of the digestive tract involves the routine administration of oral, gastric, and intravenous antibiotics to mechanically ventilated children to prevent hospital-acquired infections. It has a strong evidence base in adults, with limited pediatric evidence. Current utilization of this intervention among pediatric physicians in North America is unknown.

METHODS

An electronic survey administered to pediatric critical care and pediatric infectious disease providers in Canada. Participants were surveyed on current institutional practices, their current knowledge of the evidence base, and perceptions of the risks and benefits of the intervention. Descriptive statistics were utilized.

RESULTS

50 out of 143 (35%) surveyed responded. No hospital in Canada routinely performs SDD and the majority of respondents (74%) have neutral opinions on the subject of SDD. There was concern for increasing antibiotic resistance (43%) and some disagreement with the intravenous component of SDD (46%). The majority of respondents stated a need for pediatric-specific evidence before integrating SDD into their practice, even if further, large adult RCTs were performed.

CONCLUSION

Among surveyed providers, there is little knowledge and no use of selective digestive decontamination for the prevention of hospital-acquired infections. Before interventional studies are performed in pediatric practice, there is a need for study of facilitators, barriers and acceptability of SDD in practice.

Prophylactic oral/topical non-absorbed antifungal agents to prevent invasive fungal infection in very low birth weight infants

BACKGROUND

Invasive fungal infection is an important cause of mortality and morbidity in very preterm or very low birth weight infants. Uncertainty exists about the effect of prophylactic oral/topical non-absorbed antifungals to reduce mucocutaneous colonisation and so limit the risk of invasive fungal infection in this population.

OBJECTIVES

To assess the effect of prophylactic oral/topical non-absorbed antifungal therapy on the incidence of invasive fungal infection, mortality and morbidity in very preterm or very low birth weight infants.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL: The Cochrane Library, 2015, Issue 7), MEDLINE, EMBASE, and CINAHL (to May 2015), conference proceedings, and previous reviews.

SELECTION CRITERIA

Randomised controlled trials or quasi-randomised controlled trials that compared the effect of prophylactic oral/topical non-absorbed antifungal therapy versus placebo or no drug or another antifungal agent or dose regimen in very preterm or very low birth weight infants.

DATA COLLECTION AND ANALYSIS

We extracted data using the standard methods of the Cochrane Neonatal Review Group with separate evaluation of trial quality and data extraction by two review authors.

MAIN RESULTS

Four trials, in which a total of 1800 infants participated, compared oral/topical non-absorbed antifungal prophylaxis (nystatin or miconazole) with placebo or no drug. These trials had various methodological weaknesses including quasi-randomisation, lack of allocation concealment, and lack of blinding of intervention and outcomes assessment. The incidence of invasive fungal infection was very high in the control groups of three of these trials. Meta-analysis found a statistically significant reduction in the incidence of invasive fungal infection (typical risk ratio 0.20, 95% confidence interval 0.14 to 0.27; risk difference -0.18, -0.21 to -0.15) but substantial statistical heterogeneity was present. We did not find a statistically significant effect on mortality (typical risk ratio 0.87, 0.72 to 1.05; risk difference -0.03, -0.06 to 0.01). None of the trials assessed posthospital discharge outcomes. Three trials (N = 326) assessed the effect of oral/topical non-absorbed versus systemic antifungal prophylaxis. Meta-analyses did not find any statistically significant differences in the incidences of invasive fungal infection or all-cause mortality.

AUTHORS' CONCLUSIONS

The finding of a reduction in risk of invasive fungal infection in very low birth weight infants treated with oral/topical non-absorbed antifungal prophylaxis should be interpreted cautiously because of methodological weaknesses in the included trials. Further large randomised controlled trials in current neonatal practice settings are needed to resolve this uncertainty. These trials might compare oral/topical non-absorbed antifungal agents with placebo, with each other, or with systemic antifungal agents and should include an assessment of effect on long-term neurodevelopmental outcomes.

Prophylactic oral/topical non-absorbed antifungal agents to prevent invasive fungal infection in very low birth weight infants

BACKGROUND

Invasive fungal infection is an important cause of mortality and morbidity in very preterm or very low birth weight infants. Uncertainty exists about the effect of prophylactic oral/topical non-absorbed antifungals to reduce mucocutaneous colonisation and so limit the risk of invasive fungal infection in this population.

OBJECTIVES

To assess the effect of prophylactic oral/topical non-absorbed antifungal therapy on the incidence of invasive fungal infection, mortality and morbidity in very preterm or very low birth weight infants.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL: The Cochrane Library, 2012, Issue 3), MEDLINE, EMBASE, and CINAHL (to August 2012), conference proceedings, and previous reviews.

SELECTION CRITERIA

Randomised controlled trials or quasi-randomised controlled trials that compared the effect of prophylactic oral/topical non-absorbed antifungal therapy versus placebo or no drug or another antifungal agent or dose regimen in very preterm or very low birth weight infants.

DATA COLLECTION AND ANALYSIS

We extracted data using the standard methods of the Cochrane Neonatal Review Group with separate evaluation of trial quality and data extraction by two review authors.

MAIN RESULTS

Four trials, in which a total of 1800 infants participated, compared oral/topical non-absorbed antifungal prophylaxis (nystatin or miconazole) with placebo or no drug. These trials had various methodological weaknesses including quasi-randomisation, lack of allocation concealment, and lack of blinding of intervention and outcomes assessment. The incidence of invasive fungal infection was very high in the control groups of three of these trials. Meta-analysis found a statistically significant reduction in the incidence of invasive fungal infection [typical risk ratio 0.20 (95% confidence interval 0.14 to 0.27); risk difference -0.18 (-0.21 to -0.16)] but substantial statistical heterogeneity was present. We did not find a statistically significant effect on mortality [typical risk ratio 0.87 (0.72 to 1.05); risk difference -0.03 (-0.06 to 0.01)]. None of the trials assessed posthospital discharge outcomes.Two trials (N = 265) assessed the effect of oral/topical non-absorbed versus systemic antifungal prophylaxis. Meta-analyses did not find any statistically significant differences in the incidences of invasive fungal infection or all-cause mortality.

AUTHORS' CONCLUSIONS

The finding of a reduction in risk of invasive fungal infection in very low birth weight infants treated with oral/topical non-absorbed antifungal prophylaxis should be interpreted cautiously because of methodological weaknesses in the included trials. Further large randomised controlled trials in current neonatal practice settings are needed to resolve this uncertainty. These trials might compare oral/topical non-absorbed antifungal agents with placebo, with each other, or with systemic antifungal agents and should include an assessment of effect on long-term neurodevelopmental outcomes.

Effect of selective decontamination on antimicrobial resistance in intensive care units: a systematic review and meta-analysis

BACKGROUND

Many meta-analyses have shown reductions in infection rates and mortality associated with the use of selective digestive decontamination (SDD) or selective oropharyngeal decontamination (SOD) in intensive care units (ICUs). These interventions have not been widely implemented because of concerns that their use could lead to the development of antimicrobial resistance in pathogens. We aimed to assess the effect of SDD and SOD on antimicrobial resistance rates in patients in ICUs.

METHODS

We did a systematic review of the effect of SDD and SOD on the rates of colonisation or infection with antimicrobial-resistant pathogens in patients who were critically ill. We searched for studies using Medline, Embase, and Cochrane databases, with no limits by language, date of publication, study design, or study quality. We included all studies of selective decontamination that involved prophylactic application of topical non-absorbable antimicrobials to the stomach or oropharynx of patients in ICUs, with or without additional systemic antimicrobials. We excluded studies of interventions that used only antiseptic or biocide agents such as chlorhexidine, unless antimicrobials were also included in the regimen. We used the Mantel-Haenszel model with random effects to calculate pooled odds ratios.

FINDINGS

We analysed 64 unique studies of SDD and SOD in ICUs, of which 47 were randomised controlled trials and 35 included data for the detection of antimicrobial resistance. When comparing data for patients in intervention groups (those who received SDD or SOD) versus data for those in control groups (who received no intervention), we identified no difference in the prevalence of colonisation or infection with Gram-positive antimicrobial-resistant pathogens of interest, including meticillin-resistant Staphylococcus aureus (odds ratio 1·46, 95% CI 0·90-2·37) and vancomycin-resistant enterococci (0·63, 0·39-1·02). Among Gram-negative bacilli, we detected no difference in aminoglycoside-resistance (0·73, 0·51-1·05) or fluoroquinolone-resistance (0·52, 0·16-1·68), but we did detect a reduction in polymyxin-resistant Gram-negative bacilli (0·58, 0·46-0·72) and third-generation cephalosporin-resistant Gram-negative bacilli (0·33, 0·20-0·52) in recipients of selective decontamination compared with those who received no intervention.

INTERPRETATION

We detected no relation between the use of SDD or SOD and the development of antimicrobial-resistance in pathogens in patients in the ICU, suggesting that the perceived risk of long-term harm related to selective decontamination cannot be justified by available data. However, our study indicates that the effect of decontamination on ICU-level antimicrobial resistance rates is understudied. We recommend that future research includes a non-crossover, cluster randomised controlled trial to assess long-term ICU-level changes in resistance rates.

FUNDING

None.

Beyond bacteria: a study of the enteric microbial consortium in extremely low birth weight infants

Extremely low birth weight (ELBW) infants have high morbidity and mortality, frequently due to invasive infections from bacteria, fungi, and viruses. The microbial communities present in the gastrointestinal tracts of preterm infants may serve as a reservoir for invasive organisms and remain poorly characterized. We used deep pyrosequencing to examine the gut-associated microbiome of 11 ELBW infants in the first postnatal month, with a first time determination of the eukaryote microbiota such as fungi and nematodes, including bacteria and viruses that have not been previously described. Among the fungi observed, Candida sp. and Clavispora sp. dominated the sequences, but a range of environmental molds were also observed. Surprisingly, seventy-one percent of the infant fecal samples tested contained ribosomal sequences corresponding to the parasitic organism Trichinella. Ribosomal DNA sequences for the roundworm symbiont Xenorhabdus accompanied these sequences in the infant with the greatest proportion of Trichinella sequences. When examining ribosomal DNA sequences in aggregate, Enterobacteriales, Pseudomonas, Staphylococcus, and Enterococcus were the most abundant bacterial taxa in a low diversity bacterial community (mean Shannon-Weaver Index of 1.02±0.69), with relatively little change within individual infants through time. To supplement the ribosomal sequence data, shotgun sequencing was performed on DNA from multiple displacement amplification (MDA) of total fecal genomic DNA from two infants. In addition to the organisms mentioned previously, the metagenome also revealed sequences for gram positive and gram negative bacteriophages, as well as human adenovirus C. Together, these data reveal surprising eukaryotic and viral microbial diversity in ELBW enteric microbiota dominated bytypes of bacteria known to cause invasive disease in these infants.

The role of admission surveillance cultures in patients requiring prolonged mechanical ventilation in the intensive care unit

We undertook a prospective observational cohort study in intensive care unit (ICU) patients requiring mechanical ventilation for four days or more to evaluate normal and abnormal bacterial carriage on admission detected by surveillance cultures of throat and rectum. We assessed the importance of surveillance and diagnostic cultures for the early detection of resistance to third generation cephalosporins employed as the parenteral component of the selective decontamination of the digestive tract. Finally, we sought the risk factors of abnormal carriage on admission to the ICU. During the 58-month study 621 patients were included: 186 patients (30%) carried abnormal flora including methicillin-resistant Staphylococcus aureus (MRSA) and aerobic Gram negative bacilli (AGNB) on admission to the ICU Both MRSA and AGNB carriers were more commonly present in the hospital group of patients than in patients referred from the community (P < 0.001), although overgrowth was equally present both in community and in hospital patients. The incidence of infections during ICU stay was higher in abnormal (n=120, 64.5%) than in normal carriers (n=185, 42.5%) (P < 0.0001), with an odds ratio of 2.46 (95% confidence interval 1.72 to 3.51). Third generation cephalosporins covered ICU admission flora in 482 (78%) of the studied population. AGNB resistant to cephalosporins and MRSA were detected in surveillance cultures of 139 patients (22%), while the same resistant micro-organisms were identified only in 49 diagnostic samples (7.9%). Parenteral cephalosporins were modified in patients with abnormal flora (P < 0.0001). One hundred and ninety-six patients received antibiotics before admission to the ICU and 42% carried AGNB resistant to cephalosporins. Previous antibiotic use was the only risk factor for abnormal carriage in the multivariate analysis (OR 3.5; 95% confidence interval 2.1 to 5.8). The knowledge of carriage on admission using surveillance cultures may help intensivists to identify patients with abnormal carriage on admission and resistant bacterial strains at an early stage even when diagnostic samples are negative. Third generation cephalosporins covered admission flora in about 80% of the enrolled population and were modified in patients with abnormal flora who received antibiotic therapy before ICU admission. Our finding of overgrowth present on admission may justify the immediate administration of enteral antimicrobials.

Candida parapsilosis: a review of its epidemiology, pathogenesis, clinical aspects, typing and antimicrobial susceptibility

The Candida parapsilosis family has emerged as a major opportunistic and nosocomial pathogen. It causes multifaceted pathology in immuno-compromised and normal hosts, notably low birth weight neonates. Its emergence may relate to an ability to colonize the skin, proliferate in glucose-containing solutions, and adhere to plastic. When clusters appear, determination of genetic relatedness among strains and identification of a common source are important. Its virulence appears associated with a capacity to produce biofilm and production of phospholipase and aspartyl protease. Further investigations of the host-pathogen interactions are needed. This review summarizes basic science, clinical and experimental information about C. parapsilosis.

Prophylactic oral/topical non-absorbed antifungal agents to prevent invasive fungal infection in very low birth weight infants

BACKGROUND

Invasive fungal infection is an important cause of mortality and morbidity in very preterm (< 32 weeks gestation) or very low birth weight (VLBW) infants. Clinical uncertainly exists about the effect of prophylactic oral/topical non-absorbed antifungals to reduce mucocutaneous colonisation and so limit the risk of invasive fungal infection in this population.

OBJECTIVES

To assess the effect of prophylactic oral/topical non-absorbed antifungal therapy on the incidence of invasive fungal infection, mortality and morbidity in VLBW infants.

SEARCH STRATEGY

The standard search strategy of the Cochrane Neonatal Review Group was used. This included searches of the Cochrane Controlled Trials Register (The Cochrane Library, Issue 2, 2009), MEDLINE (1966 - May 2009), EMBASE (1980 - May 2009), conference proceedings, and previous reviews.

SELECTION CRITERIA

Randomised controlled trials that compared the effect of prophylactic oral/topical non-absorbed antifungal therapy versus placebo or no drug or another antifungal agent or dose regimen in very preterm or VLBW infants.

DATA COLLECTION AND ANALYSIS

Data were extracted using the standard methods of the Cochrane Neonatal Review Group with separate evaluation of trial quality and data extraction by each review author and synthesis of data using relative risk (RR) and risk difference (RD) and weighted mean difference (WMD).

MAIN RESULTS

Three trials, in which a total of 1625 infants participated, have compared oral/topical non-absorbed antifungal prophylaxis (nystatin or miconazole) with placebo or no drug. These trials had various methodological weaknesses including quasi-randomisation, lack of allocation concealment, and lack of blinding of intervention and outcomes assessment. The incidence of invasive fungal infection was very high in the control groups of two of the included trials. Meta-analysis found a statistically significant reduction in the incidence of invasive fungal infection [typical RR 0.19 (95% confidence interval (CI) 0.14, 0.27); typical RD -0.19 (95% CI -0.22,-0.16)] but substantial statistical heterogeneity was detected. A statistically significant effect on mortality was not found [typical RR 0.88 (95% CI 0.72, 1.06); typical RD -0.02 (95% CI -0.06, 0.01)]. Long-term outcomes were not assessed by any of the trials.One small trial (N = 21) that assessed the effect of oral/topical non-absorbed antifungal prophylaxis (nystatin) compared with systemic antifungal (fluconazole) prophylaxis was underpowered to exclude important clinical effects.

AUTHORS' CONCLUSIONS

The finding of a reduction in risk of invasive fungal infection in infants treated with oral/topical non-absorbed antifungal prophylaxis should be interpreted cautiously because of methodological weaknesses in the included trials. Further large randomised controlled trials in current neonatal practice settings are needed to resolve this uncertainty. These trials might compare oral/topical non-absorbed antifungal agents with placebo, with each other, or with systemic antifungal agents and should include an assessment of effect on long-term neurodevelopmental outcomes.

Candida parapsilosis fungemia in neonates: genotyping results suggest healthcare workers hands as source, and review of published studies

An outbreak of Candida parapsilosis fungemia involving 17 neonatal intensive care unit (NICU) patients was studied. There were 14 blood culture and nine colonizing isolates from other sites available. The hands of NICU healthcare workers (HCW) yielded eight isolates. Screening of the isolates by random amplified polymorphic DNA (RAPD) method showed only three profiles. Typing by restriction fragment length polymorphism (RFLP) revealed all blood isolates were RFLP subtype VII-1. Among the nine infant colonizing isolates, there were four different RFLP subtypes; four of the isolates were subtype VII-1. Seven of the eight isolates from HCW were RFLP subtype VII-1. The majority of infant colonizers were not found in the blood, suggesting a possible direct spread of the epidemic subtype VII-1 strain from HCW hands to infant blood. The source of the infant colonizing strains is unclear, but non-VII-1 strains may be largely of maternal origin and VII-1 strains from HCW. These findings reinforce prior studies that have implicated HCW hands as the source of nosocomial, including neonatal, fungemia.

Enteral vancomycin controls methicillin-resistant Staphylococcus aureus endemicity in an intensive care burn unit: a 9-year prospective study

OBJECTIVE

The aim of this study was to assess the efficacy and safety of enteral vancomycin in controlling MRSA endemicity in an intensive care burn unit.

SUMMARY BACKGROUND DATA

MRSA is a serious clinical and epidemiologic problem. It is not uncommon that the traditional maneuvers, detection and isolation of carriers, fail to control endemicity due to MRSA.

METHODS

All patients admitted to an Intensive Care Burn unit from January 1995 to February 2004 have been included in this prospective cohort study comprised 2 different periods. During period 1 (January 1995 to January 2000), barrier and isolation measures were enforced. During period 2 (February 2000 to February 2004), patients received enteral vancomycin 4 times daily in addition to selective digestive decontamination.

RESULTS

A total of 777 patients were enrolled into the study: 402 in period 1, and 375 in period 2. There were no significant differences in the characteristics of patients between the 2 periods, except for the total body surface burned area, 30.3% in period 1 and 25.61% in period 2 (P = 0.009). There was a significant reduction in the incidence of patients who acquired MRSA from 115 in period 1 to 25 in period 2 (RR, 0.22; 95% confidence interval [CI], 0.15-0.34). Similar reductions were observed in the number of patients with wound (RR, 0.20; 95% CI, 0.12-0.32), blood (RR, 0.13; 95% CI, 0.04-0.35), and tracheal aspirate (RR, 0.07; 95% CI, 0.03-0.19), samples positive for MRSA. There was no emergence of either vancomycin-resistant enterococci or Staphylococcus aureus with intermediate sensitivity to glycopeptides in period 2.

CONCLUSIONS

Enteral vancomycin is an effective and safe method to control MRSA in intensive care burn units without VRE.

Oral nystatin prophylaxis to prevent invasive candidiasis in Neonatal Intensive Care Unit

The use of oral nystatin to prevent fungal colonisation and infection in neonates in the Neonatal Intensive Care Unit (NICU) is still an open question and not yet recommended as a standard of care. To determine whether prophylactic oral nystatin results in a decreased incidence of invasive candidiasis in the newborn infants, a total of 3991 infants were divided randomly into two groups. Group A infants (n = 1995), only those neonates who were identified as yeast carriers (oral moniliasis) were treated with oral nystatin. Group B infants, all neonates who were admitted to the unit received oral nystatin, was routinely administered three times a day. Group A was divided into groups A1 and A2 (who were treated only if identified as yeast carriers). Urine and rectal cultures were taken on admission and then weekly thereafter. There were 215 (14.2%), 27 (5.6%) and 36 (1.8%) patients positive for invasive candidiasis in groups A1, A2 and B respectively. Oral nystatin prophylaxis significantly reduced the invasive candidiasis (P = 0.004) in extremely low-birth weight (ELBW) and very low-birth weight (VLBW) infants. Prophylactic administration of oral nystatine to the ELBW and VLBW infants results in a decreased risk of invasive candidiasis.

Nursing care of the premature infant with severe combined immunodeficiency disease

Diagnosis and treatment of severe combined immunodeficiency disease (SCID) is documented in fetuses, term infants, and older children; however, there is very little information on its diagnosis and treatment in premature infants. When Duke University Medical Center's first preterm infant with a known SCID history was delivered, in June 1999, there was no defined protocol for the infant's nursing care. Although many of the guidelines for nursing care of the premature infant population (< or = 36 weeks) apply, there are important considerations for preterm infants with an SCID diagnosis. This article provides background on SCID and identifies those special considerations--namely, multidisciplinary communication, infection prevention, thorough physical assessments, and parental support.

Use of surveillance cultures and enteral vancomycin to control methicillin-resistant Staphylococcus aureus in a paediatric intensive care unit

This study assessed the effects of throat and gut surveillance, combined with enteral vancomycin, on gut overgrowth, transmission of methicillin-resistant Staphylococcus aureus (MRSA), infections and mortality in patients admitted to a paediatric intensive care unit (PICU). A 4-year prospective observational study was undertaken with 1241 children who required ventilation for >or=4 days. Patients identified as MRSA carriers following surveillance cultures of throat and rectum received enteral vancomycin. Twenty-nine (2.4%) children carried MRSA, 19 on admission and nine during treatment in the PICU; one patient was not able to be evaluated. Overgrowth was present in 22 (75%) of the carriers. Ten (0.8%) children developed 21 MRSA infections (15 exogenous infections in eight children at a median of 8 days (IQR 3-10.5); five primary endogenous infections at a median of 3 days (IQR 1-25) in three children when they were in overgrowth status; one child developed both types of infection). Enteral vancomycin reduced gut overgrowth significantly, completely preventing secondary endogenous infections. Transmission occurred on nine occasions over a period of 4 years. Four patients died, two (5.9%) with MRSA infection, giving a mortality (11.8%) similar to the study population (9.8%). No emergence of vancomycin-resistant enterococci or S. aureus with intermediate susceptibility to vancomycin was detected. A policy based on throat and gut surveillance, combined with enteral vancomycin, for critically-ill children who were MRSA carriers was found to be effective and safe, and challenges the recommended guidelines of nasal swabbing followed by topical mupirocin.

Neonatal candidiasis

In neonates born weighing less than 750 g, invasive candidates is common and often fatal. This situation provides an opportunity to study antifungal prophylaxis and treatment in this patient population, in which the pharmacokinetics, safety, and efficacy of antifungal products are unknown. The disease is less prevalent in larger, more mature, infants. Although some pharmacokinetic data for some products are available for term and near-term infants, optimal product choice, closing, and other treatment strategies also are unknown in this older age group.

Control of imported and acquired methicillin-resistant Staphylococcus aureus (MRSA) in mechanically ventilated patients: a dose-response study of enteral vancomycin to reduce absolute carriage and infection

This study aimed to quantify the animate source provided by the patients using the concept of "absolute carriage" by multiplying the carrier rate by the level of carriage; and to compare the impact of a low and high dose of an oropharyngeal vancomycin gel on the absolute MRSA carriage and infection. In all, 265 patients were included, 126 were MRSA positive. Fifty-five patients received 2% vancomycin gel during the first year whilst 4% vancomycin gel was given to 50 patients during the second year. Surveillance swabs of throat and rectum were obtained from all eligible patients on admission and then twice weekly. The vancomycin protocol was started as soon as the surveillance cultures were positive for MRSA. Those patients received one gram of enteral vancomycin daily, divided into four doses. During the first year 2% vancomycin gel 4 ml (80 mg) was applied in the oropharynx in four doses in addition to the enteral solution (Group A). During the second year 4% vancomycin gel 4 ml (160 mg) was used (Group B). The absolute carriage was high during both periods: 3.6 for Group A, and 3.2 for Group B. The 4% vancomycin protocol significantly reduced the absolute carriage, compared to the 2% vancomycin protocol: 2.6 versus 1.5 (P < 0.01). Significant reduction in secondary endogenous infections was found in the second year: seven versus 15 patients (P < 0.05). A total of 3,588 microbiological samples were processed. Neither Staphylococcus aureus with intermediate sensitivity to vancomycin (VISA) nor vancomycin-resistant enterococci (VRE) were detected.

Handwashing in the intensive care unit: a big measure with modest effects

Handwashing is widely accepted as the cornerstone of infection control in the intensive care unit. Nosocomial infections are frequently viewed as an indicator of poor compliance of handwashing. The aim of this review is to evaluate the effectiveness of handwashing on infection rates in the intensive care unit, and to analyse the failure of handwashing. A literature search identified nine studies that evaluated the impact of handwashing or hand hygiene on infection rates, and demonstrated a low level of evidence for the efforts to control infection with handwashing. Poor compliance cannot be blamed as the only reason for the failure of handwashing to control infection. Handwashing on its own does not abolish, but only reduces transmission, as it is dependent on the bacterial load on the hand of healthcare workers. Finally, recent studies, using surveillance cultures of throat and rectum, have shown that, under ideal circumstances, handwashing can only influence 40% of all intensive care unit infections. A randomised clinical trial with the intensive care as randomisation unit is required to support handwashing as the cornerstone of infection control.

Significance of amplified fragment length polymorphism in identification and epidemiological examination of Candida species colonization in children undergoing allogeneic stem cell transplantation

Candida albicans and non-C. albicans Candida species are increasingly being isolated from patients in high-risk categories, most notably, those who have undergone stem cell transplantation (SCT). Identification of the presence of non-C. albicans Candida species early in the course of the transplant procedure is important, as these species exhibit different sensitivities to the available antifungal treatments and cause mortality at rates that vary from those for C. albicans. Amplified fragment length polymorphism (AFLP) analysis has been shown to be a reliable method of reproducibly identifying medically important Candida species. We investigated the use of serial AFLP analysis of 54 routine surveillance cultures for the identification and epidemiological examination of Candida sp. colonization in five consecutive children undergoing allogeneic SCT. One child became colonized with a C. albicans strain and remained colonized with this strain during the whole admission period. Another child had persistent colonization with a C. albicans strain with striking variations in its AFLP patterns over time, which was considered indicative of microevolution. Candida dubliniensis, Candida lusitaniae, and Saccharomyces cerevisiae were identified in the three remaining patients, with two children being simultaneously and transiently colonized with different species. These findings show that colonization with yeasts during transplantation is a complex and dynamic interaction between the host and the organism(s). In our study three strains from eight separate time points were incorrectly identified as C. albicans by a rapid enzyme test. AFLP analysis of surveillance cultures allowed more accurate and informative epidemiological evaluations of pathogenic yeasts in children during transplantation.

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.

Effectiveness and safety of enteral vancomycin to control endemicity of methicillin-resistant Staphylococcus aureus in a medical/surgical intensive care unit

A prospective trial was undertaken to assess the effectiveness and safety of enteral vancomycin in controlling methicillin-resistant Staphylococcus aureus (MRSA) in an endemic setting. Over the 49 month period patients aged >14 years were enrolled, following admission to a medical/surgical intensive care unit (ICU) and expected to require ventilation for three days or more. A total of 799 patients were included in the trial. Period one, 1 July 1996-30 April 1997, (N=140), was observational. During period two, 1 May 1997-30 September 1998, (N=258), surveillance samples were obtained. MRSA carriers were isolated and received enteral vancomycin. During period three, 1 October 1998-31 July 2000, (N=400), all ventilated patients were given selective digestive decontamination (SDD) with polymyxin E, tobramycin, amphotericin B and vancomycin and four days of intravenous cefotaxime. The primary endpoints were: (1) incidence of patients with diagnostic samples positive for MRSA acquired on the ICU; (2) incidence of patients with vancomycin-resistant enterococci (VRE) in surveillance or diagnostic samples; (3) incidence of patients with samples positive for S. aureus with intermediate sensitivity to glycopeptides (GISA). The incidence of patients with MRSA in diagnostic samples were 31%, 14%, and 2% in periods one, two and three, respectively (P<0.001). There was a VRE outbreak involving 13 patients during period three. VRE disappeared with no change in policy. GISA was not detected. These findings support the effectiveness and safety of enteral vancomycin in the control of MRSA.

Prophylactic oral antifungal agents to prevent systemic candida infection in preterm infants

BACKGROUND

Systemic fungal infection has increased in prevalence in neonatal intensive care units (NICU) caring for very low birth weight infants. It is associated with a prolonged stay and an increase in morbidity and mortality. An assessment of the use of oral prophylactic antifungals to prevent systemic infection is needed.

OBJECTIVES

To assess whether the prophylactic administration of oral antifungal agents to very preterm infants reduces the occurrence of systemic fungal infection.

SEARCH STRATEGY

The standard methods of the Cochrane Collaboration and its Neonatal Review Group were used. Searches were carried out up to July 2003 on the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library Issue 2, 2003), MEDLINE from 1966, EMBASE from 1980, CINAHL from 1992. Abstracts from SPR (1993 - 2003) and ESPR (1995 to 2002) were hand searched.

SELECTION CRITERIA

Randomized and quasi randomized controlled trials in very low birth weight or very preterm infants in which an oral antifungal agent was compared with placebo or no treatment or another oral antifungal agent

DATA COLLECTION AND ANALYSIS

Data were extracted using the standard methods of the Cochrane Neonatal Review Group, with separate evaluation of the trial quality and data extraction undertaken by each author. Results were reported using relative risk (RR) and risk difference (RD) and weighted mean difference (WMD). 95% confidence intervals were reported.

MAIN RESULTS

We identified three eligible trials, one comparing nystatin with no treatment (67 infants), one comparing miconazole with placebo (600 infants), and one comparing nystatin with fluconazole (21 infants). As the two trials comparing nystatin or miconazole with placebo or no treatment were clinically quite different, meta-analysis was not performed. In the trial of nystatin versus no treatment, systemic fungal infection was significantly reduced [RR 0.19 (0.04,0.78)] in the group treated with nystatin. In the study comparing miconazole with placebo there was no significant effect on systemic fungal infection [RR 1.32 (0.46,3.75)]. Neither study found a significant effect on mortality, and there was no significant difference in the mean number of days infants received ventilation or stayed in the neonatal intensive care unit. In the small trial comparing oral fluconazole with nystatin, no significant difference in systemic fungal infection [RR 0.17 (0.01, 2.84)] or mortality [RR 0.17 (0.01, 2.84)] was reported. Adverse drug reactions were not reported in any study.

REVIEWER'S CONCLUSIONS

There is insufficient evidence to support the use of prophylactic oral antifungal agents in very low birth weight infants in the neonatal intensive care unit. Randomised controlled trials in current neonatal practice settings are needed, comparing oral antifungal agents with placebo and with each other and including an assessment of side effects, in order to determine whether oral antifungal agents have a role in preventing systemic fungal infections in preterm infants.

Strategies for prevention of neonatal invasive candidiasis

A single-center randomized, placebo-controlled trial has found that intravenous fluconazole prophylaxis in preterm infants < or = 1,000 g with a central venous catheter or endotracheal tube until such infants no longer required intravenous access or attained 6 weeks postnatal age was effective in preventing fungal sepsis. Infants at high risk for fungal sepsis are preterm infants < or = 32 weeks' gestation with one or more of the following additional risk factors: receipt of more than 2 antibiotics, third-generation cephalosporins, histamine-2 receptor antagonists, postnatal steroids, parenteral nutrition, or intravenous lipids; central venous catheter, skin disruption, dermatitis, necrotizing enterocolitis, or abdominal surgery. Further study in larger populations is needed to explore whether antifungal chemoprophylaxis or other strategies may be effective in preventing fungal infection in high-risk neonates. Effective prophylaxis strategies will decrease the high mortality and morbidity associated with fungal infection in high risk infants.

All great truths are iconoclastic: selective decontamination of the digestive tract moves from heresy to level 1 truth

OBJECTIVE

The objective was to compare evidence of the effectiveness, costs and safety of the traditional parenteral antibiotic-only approach against that gathered from 53 randomised trials involving more than 8,500 patients and six meta-analyses on selective decontamination of the digestive tract (SDD) to control infection on the intensive care unit (ICU). PHILOSOPHY: Traditionalists believe that all infections are due to breaches of hygiene except those established in the first 2 days, and that all micro-organisms can cause death. In contrast, newer insights show that transmission via the hands of carers are responsible only for infections occurring after one week, and that only a limited range of 15 potential pathogens contribute to mortality. INTERVENTIONS TO PREVENT ICU INFECTION: The traditional approach is based on hand disinfection aiming at the prevention of transmission of all micro-organisms, to control all infections that occur after 2 days on the ICU. The second feature is the restrictive use of systemic antibiotics, only in cases of microbiologically proven infection. In contrast, SDD aims to control the three types of infection: primary, secondary endogenous and exogenous due to 15 potential pathogens. The classical SDD tetralogy comprises four components: (i) a parenteral antibiotic, cefotaxime, administered for three days to prevent primary endogenous infections typically occurring "early"; (ii) the oropharyngeal and enteral antimicrobials, polymyxin E, tobramycin and amphotericin B administered in throat and gut throughout the treatment on the ICU to prevent secondary endogenous infections tending to develop "late"; (iii) a high standard of hygiene to control transmission of potential pathogens; and (iv) surveillance samples of throat and rectum to monitor the efficacy of the treatment.

ENDPOINTS

(i) Infectious morbidity; (ii) mortality; (iii) antimicrobial resistance; and (iv) costs.

RESULTS

Properly designed trials on hand disinfection have never demonstrated a reduction in either pneumonia and septicaemia, or mortality. Two randomised trials using restrictive antibiotic policies failed to show a survival benefit at 28 days. In both trials the proportion of resistant isolates obtained from the lower ways was >60% despite significantly less use of antibiotics in the test group. A formal cost effectiveness analysis of the traditional antibiotic policies has not been performed. On the other hand, two meta-analyses have shown that SDD reduces the odds ratio for lower airway infections to 0.35 (0.29-0.41) and mortality to 0.80 (0.69-0.93), with a 6% overall mortality reduction from 30% to 24%. No increase in the rate of super infections due to resistant bacteria could be demonstrated over a period of 20 years of clinical research. Four randomised trials found the cost per survivor to be substantially lower in patients receiving SDD than for those traditionally managed.

CONCLUSIONS

The traditionalists still rely on level 5 evidence, i.e. expert opinion, with a grade E recommendation, whilst the proponents of SDD are able to cite level 1 evidence allowing a grade A recommendation in their attempts to control infection on the ICU. The main reason for SDD not being widely used is the primacy of opinion over evidence.

Enteral vancomycin to control methicillin-resistant Staphylococcus aureus outbreak in mechanically ventilated patients

BACKGROUND

Screening for and treating gut carriage of methicillin-resistant Staphylococcus aureus (MRSA) may control transmission and subsequent endemicity of MRSA.

OBJECTIVE

Enteral vancomycin was evaluated as a measure to control an outbreak of MRSA infection in the intensive care unit (ICU).

METHODS

During the 8-month study of sequential design, 176 patients were admitted, 65 (37%) of whom required a minimum of 3 days of ventilation. Forty-four patients were studied in the first 5 months, during which traditional measures were reinforced (control group). During the following 3 months, 13 of 21 patients developed MRSA carriage and received 2 g/day of enteral vancomycin, with high standards of hygiene maintained (treatment group).

RESULTS

Thirty-three MRSA infections occurred in 22 patients (50%) in the control group, whereas 2 patients (9.5%) had 2 MRSA infections in the treatment group (P <.05 for carriage, infection rates, and episodes). Of the 33 MRSA infections in the control group, 27 were due to MRSA acquired in the ICU, whereas the 2 infections in the treatment group were primary endogenous (ie, caused by MRSA present in the patient's admission flora). The probability of developing an MRSA infection was reduced in patients receiving enteral vancomycin compared with patients in the control group (odds ratio, 0.37; 95% CI, 0.24-0.58). Enteral vancomycin significantly reduced the level of MRSA carriage; the mean carriage index was 1.01 in the control group versus 0.58 in the test group (P <.05). Neither vancomycin-resistant enterococci nor vancomycin-intermediate Staphylococcus aureus were isolated from either surveillance or diagnostic samples.

CONCLUSIONS

The eradication of MRSA gut carriage by enteral vancomycin in a small subset of ICU patients was effective in the control of an MRSA outbreak.

Low rate of Candida parapsilosis-related colonization and infection in hospitalized preterm infants: a one-year prospective study

We determined the rate of Candida parapsilosis colonization in preterm neonates (NN) and the relationship between colonization and systemic infection through a prospective study in the Neonatal Intensive Care Unit of a university hospital. All NN born at a gestational age of 32 weeks or less were included. Specimens from rectum, mouth and retro-auricular skin were obtained at admission and weekly thereafter. All samples were inoculated on to Sabouraud agar, CHROMagar and Dixon media. Candida species were identified using API Candida and API 20C. DNA analysis was performed using pulse field gel electrophoresis.Fifty-four patients were included (mean age: 30 +/- 1.5 weeks; mean birthweight: 1347 +/- 301 g; male: 40%). Fungal colonization was detected in 43 (79.6%). Causative agents were C. parapsilosis (N= 7);Malassezia furfur (N= 30);C. albicans (N= 21), C. guillermondii (N= 1). No sample was positive for two different yeasts at the same time. C. parapsilosis colonization included anal (N= 6), buccal (N= 1), and skin (N= 2). The average age at time of colonization was 17.8+/-9.8 days. Neither fungal septicaemia nor death were observed in colonized infants. Two central venous catheters were found to be colonized, one with C. parapsilosis and one with M. furfur. Logistic regression showed a link between colonization and gestational age alone. Three different DNA profiles were observed. This study suggests that in our units, the occurrence of C. parapsilosis colonization is low and bears no relation to systemic infection. The systematic identification of C. parapsilosis carriers for the purposes of isolation and preventive treatment does not appear to be warranted.

Clinical use of oral nystatin in the prevention of systemic candidosis in patients at particular risk

Systemic candidosis is currently a major concern among certain groups of patients at particular risk because of recent treatment modalities. To prevent spread of Candida albicans, in particular, from the orogastrointestinal tract antimycotic treatment would appear beneficial. So far, however, suitable drugs are rare. Polyenes, and in particular oral nystatin, are the main ones considered so far. More recently, the oral azoles have provided therapeutic alternatives. In this review the current role of nystatin and, in particular nystatin tablets, which are better accepted than suspensions at higher dose levels, is described, focusing on efficacy and safety as determined in controlled trials. Recent evidence suggests that oral application of nystatin tablets can be considered both efficacious and safe in the appropriate context. The relative potency of oral nystatin and systemic azoles, particularly ketoconazole and fluconazole, awaits final determination.