Annette Schuermans

Methicillin-resistant Staphylococcus aureus colonization is associated with higher mortality in nursing home residents with impaired cognitive status

OBJECTIVES: To assess the effect of methicillin‐resistant Staphylococcus aureus (MRSA) colonization on morbidity and mortality of nursing home residents.

Pasteurization of mother's own milk for preterm infants does not reduce the incidence of late-onset sepsis.

Background: Feeding preterm infants human milk has a beneficial effect on the risk of late-onset sepsis (LOS). Due to lack of microbiological standards, practices such as pasteurization of mother’s own milk differ widely among neonatal intensive care units worldwide. Objectives: To investigate whether pasteurization of mother’s own milk for very-low-birth-weight (VLBW) infants influences the incidence and severity of infection-related outcomes. Methods: In this randomized controlled trial, preterm infants (gestational age <32 weeks and/or birth weight <1,500 g) received either raw or pasteurized mother’s own milk during the first 8 weeks of life. The primary outcome was the incidence of proven LOS. A dose-response relation was verified, i.e. the dependence of the risk of sepsis on the actual and cumulative quantities of mother’s own milk. Results: This study included 303 VLBW infants (mean birth weight: 1,276 g; mean gestational age: 29 weeks) whose baseline and nutritional characteristics were similar. The incidence of laboratory-confirmed sepsis was not statistically different in infants fed raw milk compared to infants who received pasteurized milk: 22/151 (0.15, CI: 0.08–0.20) and 31/152 (0.20, CI: 0.14–0.27), respectively (RR: 0.71; 95% CI: 0.43–1.17). A significant dose-response relation was observed between the adjusted quantity of enteral feeding and the risk of LOS, regardless of the type of feeding. Conclusion: For preterm infants, pasteurization of mother’s own milk shows a trend towards an increase in infectious morbidity, although no statistical significance was reached. Practices should focus on collection, storage and labeling procedures to ensure the safety and quality of expressed milk.

Evaluation of the Copan ESwab transport system for the detection of methicillin-resistant Staphylococcus aureus: a laboratory and clinical study

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as an important pathogen. Successful detection starts with the selection of an appropriate specimen collection device. The Copan ESwab, a new swab, was compared with a commonly used Copan Venturi swab for the recovery of MRSA. In vitro assessment was performed according to the Clinical and Laboratory Standards Institute (CLSI) M40-A protocol. For the clinical evaluation, 24 patients with known MRSA carriage were included. The ESwab fulfilled the CLSI acceptance criteria for MRSA viability. In the clinical study, both swabs performed equally in qualitative terms of positive and negative. However, the in vitro and in vivo evaluation revealed at least 3.6-fold higher recovery of viable MRSA with the ESwab as compared with the Venturi swab. In conclusion, the ESwab may contribute to improve the quality of a MRSA screening protocol.

Expressed breast milk on a neonatal unit: a hazard analysis and critical control points approach.

With the increasing use of human milk and growing evidence of the benefits of mothers milk for preterm and ill newborns, guidelines to ensure its quality and safety are an important part of daily practice in neonatal intensive care units. Operating procedures based on hazard analysis and critical control points can standardize the handling of mothers expressed milk, thereby improving nutrition and minimizing the risk of breast milk-induced infection in susceptible newborns. Because breast milk is not sterile, microorganisms can multiply when the milk is not handled properly. Additional exogenous contamination should be prevented. Strict hygiene and careful temperature and time control are important during the expression, collection, transport, storage, and feeding of maternal milk. In contrast to formula milk, no legal standards exist for the use of expressed maternal milk. The need for additional measures, such as bacteriological screening or heat treatment, remains unresolved.

Fever of unknown origin due to inflammatory pseudotumour of lymph nodes.

The clinical features of inflammatory pseudotumour of lymph nodes, a distinct non-malignant histopathological entity firstly described in 1988, are summarized based upon a detailed analysis of 4 personal cases and 47 cases reported in the literature. The mean age of the patients is 38 years (range 8 to 82 years) and there is no gender predilection. One third present with asymptomatic lymphadenopathy and 47% present with fever, nearly all meeting the criteria of fever of unknown origin. Abdominal complaints are occasionally present. Intermittence of symptoms is common. Hepatosplenomegaly is unusual. All lymph node areas may be involved but abnormalities are mostly confined to one or two anatomic regions. No extranodal involvement has been reported although inflammatory pseudotumour may occur in several organs with similar morphological features and identical signs of inflammations. Routine blood tests are normal except for signs of inflammation. The lesions are Gallium-avid. Diagnosis is based upon typical histopathological features. The prognosis is favorable and surgical resection frequently leads to cure. Spontaneous resolution of symptoms has been reported and nonsteroidal anti-inflammatory drugs may suppress the clinical manifestations.

Intestinal Colonization Patterns of Staphylococci in Preterm Infants in Relation to Type of Enteral Feeding and Bacteremia

OBJECTIVE This study investigated the intestinal colonization with staphylococci in very low birth weight infants in relation to the type of enteral feeding and evaluated the intestine as potential source for staphylococcal bacteremia. PATIENTS AND METHODS Infants born in the Level III neonatal intensive care unit of a university hospital with a gestational age below 32 weeks and/or birth weight below 1,500 g were included in a prospective, observational study. The infants received either preterm formula or mothers own milk, with random allocation to raw or pasteurized milk. Precise viable staphylococcal counts of serial fecal specimens were examined in the first 8 weeks of life. In the case of bloodstream infection, fecal and blood isolates of staphylococci were compared by antibiotypes or pulsed-field gel electrophoresis. RESULTS One hundred fifty neonates, with a mean of 29 weeks of gestation and 1,260 g at birth, had 1,045 fecal samples analyzed and were found to be heavy carriers of staphylococci in the intestine with 10(6)-10(7) colony-forming units/g of feces from the first week of life. Colonization rate and patterns were not different in relation to the type of enteral feeding. In nearly 80% of 42 patients exhibiting a staphylococcal bloodstream infection, intestinal colonization retrieved a predominant strain that was different from the one recovered from the blood. CONCLUSIONS In very low birth weight infants, predominance of staphylococci in the gut is not related to the type of enteral feeding. An endogenous origin of staphylococcal bloodstream infection seems to play a minor role.

Prevention of fracture-related infection: a multidisciplinary care package

Fracture-related infection (FRI) remains a challenging complication. It may result in permanent functional loss or even amputation in otherwise healthy patients. For these reasons, it is important to focus attention on prevention. In treatment algorithms for FRI, antibiotic stewardship programmes have already proved their use by means of a multidisciplinary collaboration between microbiologists, surgeons, pharmacists, infectious disease physicians and nursing staff. A similar approach, however, has not been described for infection prevention. As a first step towards achieving a multidisciplinary care package for infection prevention, this review summarises the most recent guidelines published by the World Health Organization (WHO) and US National Institutes of Health Centers for Disease Control and Prevention (CDC), primarily focusing on the musculoskeletal trauma patient. The implementation of these guidelines, together with close collaboration between infection control physicians, surgeons, anaesthesiologists and nursing staff, can potentially have a beneficial effect on the rate of FRI after musculoskeletal trauma surgery. It must be stated that most evidence presented here in support of these guidelines was not obtained from musculoskeletal trauma research. Although most preventive measures described in these studies can be generalised to the musculoskeletal trauma patient, there are still important differences with nontrauma patients that require further attention. Future research should therefore focus more on this very defined patient population and more specifically on FRI prevention.

OXA-427, a new plasmid-borne carbapenem-hydrolysing class D β-lactamase in Enterobacteriaceae

Objectives: To describe a novel plasmid‐borne class D carbapenemase (CHDL) named OXA‐427 identified in several Enterobacteriaceae clinical isolates from nine patients in one Belgian hospital. Methods: OXA‐427‐producing isolates were analysed by an electrochemical imipenem hydrolysis method (BYG Carba test), Carba NP test, conventional phenotypic assays and by molecular methods (PCR, whole sequencing of the OXA‐427‐encoding plasmid and cloning). The antimicrobial resistance profile of OXA‐427 was analysed by expression of the cloned gene in Escherichia coli DH10B and J53. Results: Eleven OXA‐427‐producing Enterobacteriaceae isolates of various species were identified from clinical specimens of nine patients between March 2012 and June 2014. OXA‐427 shares only 22%‐29% amino acid identity with OXA‐48‐like enzymes and other acquired CHDL (e.g. OXA‐23, ‐24/40 and ‐58 of Acinetobacter spp.). Conversely, it appeared closely related to the chromosomal class D &bgr;‐lactamase of Aeromonas media, Aeromonas hydrophila and Aeromonas sobria (99%, 89% and 77% of identity, respectively). When expressed in E. coli, OXA‐427 hydrolysed imipenem and conferred resistance to extended‐spectrum cephalosporins (mostly ceftazidime), penicillins including temocillin, and reduced susceptibility to carbapenems. The blaOXA‐427 gene was located in a 45 kb resistance island on a 177 kb IncA/C plasmid. Conclusions: OXA‐427 is a novel CHDL most closely related to chromosomal class D &bgr;‐lactamase of A. media WS. It confers resistance to penicillins, ceftazidime and aztreonam and in some instances to carbapenems. OXA‐427, which is not detectable by classical molecular tests, caused a protracted outbreak in one university hospital over a 2 year period.

Tracing delays in infection control measures in a nosocomial norovirus outbreak.

Journal of Hospital Infection - In Press.Proof corrected by the author Available online since vendredi 11 septembre 2015

Performance of three generations of Xpert MRSA in routine practice: approaching the aim?

The aim of this study was to evaluate retrospectively the performance of the Xpert MRSA assay in routine practice and its current use in the intensive care unit (ICU) setting of our hospital, since a pre-emptive isolation strategy has been applied. A total of 6473 patients were routinely screened with ESwab for methicillin-resistant Staphylococcus aureus (MRSA) using three generations of rapid real-time polymerase chain reaction (PCR) (Cepheid GeneXpert) over three consecutive periods of time. Performance was evaluated using broth enrichment culture as the reference method. Our results show that the last generation of Xpert MRSA (NxG) assay is more specific (99.2% vs. 97.9%) but not more sensitive (77.8% vs. 86.9%) than the third generation. Considering the low prevalence of MRSA in our hospital, we obtained an overall low positive predictive value. In conclusion, it remains difficult to abandon the reference method in routine practice considering the possible implications of an erroneous MRSA result in the ICU.