Critical care of severe bronchiolitis during shortage of ICU resources.

Large seasonal outbreaks of bronchiolitis put pressure on healthcare systems and particularly on intensive care units (ICUs). ICU admission is necessary to provide respiratory support to the severest cases, otherwise bronchiolitis can result in substantial mortality. ICU resources are often insufficient and there is scant evidence to guide the ICU clinical management. Most available studies do not cover the ICU-admitted cases and do not consider the associated public health issues. We review this topic through a multidisciplinary approach from both the clinical and public health perspectives, with an analysis based on pathophysiology and cost-effectiveness. We suggest ways to optimise respiratory care, minimise ICU stay, "protect" ICU beds and, whenever possible, make them available for other critically ill children. We also provide guidance on how to prepare ICUs to work under stressful conditions due to outbreaks and to reduce the risk of nosocomial cross-contamination, particularly in ICUs caring for high-risk children. Funding: None.

Contaminated Incubators: Source of a Multispecies Enterobacter Outbreak of Neonatal Sepsis.

The genus Enterobacter includes species responsible for nosocomial outbreaks in fragile patients, especially in neonatal intensive care units (NICUs). Determining the primary source of infection is critical to outbreak management and patient outcomes. In this investigation, we report the management and control measures implemented during an Enterobacter outbreak of bloodstream infections in premature babies. The study was conducted in a French NICU over a 3-year period (2016 to 2018) and included 20 premature infants with bacteremia. The clinical and microbiological characteristics were identified, and whole-genome sequencing (WGS) was performed on bacteremia isolates. Initially, several outbreak containment strategies were carried out with no success. Next, outbreak investigation pinpointed the neonatal incubators as the primary reservoir and source of contamination in this outbreak. A new sampling methodology during "on" or "in use" conditions enabled its identification, which led to their replacement, thus resulting in the containment of the outbreak. WGS analysis showed a multiclonal outbreak. Some clones were identified in different isolation sources, including patients and neonatal incubators. In addition, microbiological results showed a multispecies outbreak with a high prevalence of Enterobacter bugandensis and Enterobacter xiangfangensis. We conclude that the NICU health care environment represents an important reservoir for Enterobacter transmission and infection. Finally, extracting samples from the neonatal incubator during active use conditions improves the recovery of bacteria from contaminated equipment. This method should be used more frequently to achieve better monitoring of the NICU for HAIs prevention. IMPORTANCE Neonatal incubators in the NICU can be an important reservoir of pathogens responsible for life-threatening outbreaks in neonatal patients. Traditional disinfection with antiseptics is not sufficient to eradicate the microorganisms that can persist for long periods in the different reservoirs. Identification and elimination of the reservoirs are crucial for outbreak prevention and control. In our investigation, using a new strategy of microbiological screening of neonatal incubators, we demonstrated that these were the primary source of contamination. After their replacement, the outbreak was controlled. This new methodology was effective in containing this outbreak and could be a viable alternative for infection prevention and control in outbreak situations involving incubators as a reservoir.

Risk factors for respiratory tract bacterial colonization in adults with neuromuscular or neurological disorders and chronic tracheostomy.

The aim of this study was to describe the endotracheal respiratory flora in a population of adults suffering from neuromuscular or neurological disorders requiring a long-term tracheostomy and to identify risk factors for colonization. We conducted a prospective and single-center observational study among patients with chronic tracheostomy admitted for planned respiratory assessment between February 2015 and December 2016. Data were collected from patient interview and medical charts with a standardized questionnaire. A tracheal aspiration was performed for each patient. Humidifiers were analysed for bacteriological contamination. Overall 77 tracheal aspirates (TA) were obtained from patients included. Pathogenic bacteria were found in 90% of cases (69/77) with a majority of Pseudomonas aeruginosa (32/77, 41%), Staphylococcus aureus (34/77, 44%) and Serratia marcesens. (22/79, 38%) Amoxicillin + Clavulanic-acid and Cefotaxime were adapted for respectively in only 28% and 35% of the subjects due to the natural resistance of organisms. No pathogenic bacteria were isolated from humidifier samples. Risk factors significantly associated with P. aeruginosa colonization were residence in a medical-care home (p = 0.01, OR = 3.8 [1.1; 15.1]) and the presence of a cuff (p = 0.003, OR = 4.4 [1.1; 20.6]). Significant quantities of pathogenic bacteria are frequently isolated from TA of tracheostomised patients in the absence of infection. The frequent resistance of these pathogens to Amoxicillin + Clavulanic-acid precludes the use of this antibiotic in the empiric treatment of pneumonia in this population.

Emergence and Within-Host Genetic Evolution of Methicillin-Resistant Staphylococcus aureus Resistant to Linezolid in a Cystic Fibrosis Patient.

Methicillin-resistant Staphylococcus aureus (MRSA) infection has increased in recent years among cystic fibrosis (CF) patients. Linezolid (LZD) is one of the antistaphylococcal antibiotics widely used in this context. Although LZD resistance is rare, it has been described as often associated with long-term treatments. Thirteen MRSA strains isolated over 5 years from one CF patient were studied for LZD resistance emergence and subjected to whole-genome sequencing (WGS). Resistance emerged after three 15-day LZD therapeutic regimens over 4 months. It was associated with the mutation of G to T at position 2576 (G2576T) in all 5 rrl copies, along with a very high MIC (>256 mg/liter) and a strong increase in the generation time. Resistant strains isolated during the ensuing LZD therapeutic regimens and until 13 months after LZD stopped harbored only 3 or 4 mutated rrl copies, associated with lower MICs (8 to 32 mg/liter) and low to moderate generation time increases. Despite these differences, whole-genome sequencing allowed us to determine that all isolates, including the susceptible one isolated before LZD treatment, belonged to the same lineage. In conclusion, LZD resistance can emerge rapidly in CF patients and persist without linezolid selective pressure in colonizing MRSA strains belonging to the same lineage.

Comparative Evaluation of Two PCR-Based Methods for Detection of Methicillin-Resistant Staphylococcus aureus (MRSA): Xpert MRSA Gen 3 and BD-Max MRSA XT.

We compared two walk-away molecular diagnostic assays, the GeneXpert MRSA Gen 3 assay and the BD-Max MRSA XT assay. A total of 119 prospective swabs and 36 culture-positive samples were tested. Xpert MRSA Gen 3 had sensitivity of 95.7% and specificity of 100% versus 87.5% and 97.1% for BD-Max. The difference in agreement with the enriched culture results was significantly in favor of the Xpert assay (P < 0.02, McNemar nonparametric text).

Role of the central venous catheter in bloodstream infections caused by coagulase-negative staphylococci in very preterm neonates.

BACKGROUND: Pathogenesis of coagulase-negative staphylococcal bloodstream infections among preterm neonates is debated: central venous catheters (CVCs) are considered the major cause and the cornerstone of prevention measures. The role of other means of transmission is unknown. METHODS: We developed a specific quantitative polymerase chain reaction assay targeting the dnaJ gene from Staphylococcus epidermidis and Staphylococcus capitis to detect DNA from CVC used in preterms. Performance of the polymerase chain reaction was tested against 2 control groups of CVC yielding positive (n = 24) or negative (n = 63) conventional cultures. We also explored retrospectively the DNA load of CVC having a negative conventional bacterial culture and obtained from 34 very preterm neonates with catheter-related bloodstream infections (CR-BSIs) established by usual clinical and biologic criteria. RESULTS: The molecular approach allowed detection of corresponding DNA from all the positive control catheters. Among the 34 episodes of CR-BSI yielding a negative conventional CVC culture, 8 (23.5%) had a positive polymerase chain reaction signal (5 S. epidermidis and 3 S. capitis). This percentage did not significantly differ according to the staphylococcal species, the delay between the CVC insertion and the beginning of the sepsis or between the blood culture collection and the CVC removal. These results conform to the previously published 70% of CR-BSI for whom the origin could be questioned. CONCLUSIONS: CVC removal in preterms is often performed in cases of CR-BSI; our study supports the hypothesis that in some cases the responsibility of CVC is questionable.

Link between carbapenemase-producing Enterobacteria carriage and cross-border exchanges: eight-year surveillance in a large French multihospitals institution.

Assistance Publique-Hôpitaux de Paris launched a specific strategy to survey and control the spread of emerging multidrug-resistant bacteria such as carbapenemase-producing Enterobacteria (CPE). Among the 63 CPE events that occurred between 2004 and 2011, 87% involved patients with a link with cross-border exchanges, justifying the recommendation to screen and isolate such patients.