Mupirocin resistance in nasal carriage of Staphylococcus aureus among healthcare workers of a tertiary care rural hospital

Prevalence of Mupirocin and Methicillin-Resistant Staphylococcus aureus in Nasal Carriage Among Healthcare Workers in an Intensive Care Unit and Post-decolonization Screening Outcomes at a Tertiary Care Hospital: A Prospective Study

INTRODUCTION

Nasal carriage of Staphylococcus species plays an important role in the epidemiology and pathogenesis of both community and healthcare-associated infections. Coinciding the emergence of methicillin-resistant Staphylococcus aureus (MRSA) is a challenge for clinicians to prevent their spread. Mupirocin is a topical antimicrobial agent approved for eradicating nasal carriage of staphylococcal species in adult patients and healthcare workers (HCWs). The increasing prevalence of mupirocin resistance among Staphylococcus aureus and coagulase-negative staphylococci species could be an important threat to the future use of mupirocin against MRSA.

OBJECTIVE

The aim of this study is to determine the prevalence of MRSA from nasal swabs of HCWs in intensive care units and its level of resistance pattern of mupirocin in all isolates of Staphylococcus species by disk diffusion and epsilometer test (E-test) and to determine post decolonization screening.

MATERIALS AND METHODS

 A total of 67 HCWs (doctors, nursing staff, technicians, and housekeeping staff) in the medical and surgical intensive care units were included in the study. Nasal swabs were collected from the subjects and cultured onto nutrient and blood agar, which were then incubated at 37ºC for 18 to 24 hours. Staphylococcus aureus and coagulase-negativeStaphylococcus species (CoNS) were identified by standard biochemical techniques. Methicillin resistance was detected by the disk diffusion method using a 30 µg cefoxitin disk as per the Clinical and Laboratory Standards Institute (CLSI) guidelines, and mupirocin resistance was detected using a 5 µg mupirocin disk. The resistance strains were further subjected to E-strip testing to determine the level of mupirocin resistance.

RESULTS

 A total of 72 isolates were grown from the 67 subjects used in this study. Nine strains (12.5%) grew S. aureus, and 52 strains (72.2%) grew CoNS. Methicillin resistance was seen in five isolates (6.9%) of S. aureus and 45 isolates (62.5%) of CoNS. Mupirocin resistance was seen in 11 isolates of methicillin-resistant coagulase-negative Staphylococcus species (MRCoNS), where three isolates (4.1%) showed low-level mupirocin resistance MuL and eight isolates (11.11%) showed high-level mupirocin resistance MuH. None of the isolates of MRSA, methicillin-sensitive Staphylococcus aureus (MSSA), and methicillin-sensitive coagulase-negative Staphylococcusspecies (MSCoNS) were resistant to mupirocin. Seven out of nine HCWs (77.8%) showed clearance of the organism after decolonization therapy.

CONCLUSION

The prevalence of emerging resistance to mupirocin in MRSA and MRCoNS is of great concern, especially in the nasal carrier state of HCWs. Hence, methicillin and mupirocin resistance in S. aureus and CoNS must be detected in HCWs as a routine protocol, and decolonization measures should be undertaken to prevent healthcare-associated infections.

OUP accepted manuscript

Background

Carriers of Staphylococcus aureus among healthcare workers (HCWs) can spread the bacteria to patients and the environment, in addition to their own risk of infection.

Objectives

To determine the prevalence of S. aureus carriers among HCWs and the rate of recolonization after decolonization therapy with mupirocin.

Methods

Nasal and hand swabs from HCWs of a tertiary care hospital in Nepal were cultured on mannitol salt agar and S. aureus isolated were identified using standard microbiological procedures. Detection of MRSA and mupirocin-resistant S. aureus (MupRSA) isolates were done phenotypically. Identified S. aureus carriers were decolonized with 2% mupirocin nasal ointment. Recolonization of the carriers was assessed monthly for the next 5 months.

Results

Among the 213 HCWs, 18.3% were S. aureus carriers (35 nasal carriers, 4 both nasal and hand carriers, and no hand carriers). Overall, 9.4% of the HCWS were MRSA carriers and none were MupRSA carriers. After decolonization, 25.6% of them were recolonized and 50.0% of the recolonization was detected after 3 months of decolonization. All recolonized carriers had only MSSA strains (which colonized only nose), and none were recolonized with MupRSA.

Conclusions

HCWs are frequent carriers of S. aureus and MRSA. Due to their continuous exposure to the hospital environment, they are at risk of colonization by this MDR organism. Regular screening and decolonization of HCWs working with high risk, vulnerable patients would reduce the risk of MRSA transmission from HCWs to patients.

Admission platelet count and indices as predictors of outcome in children with severe Sepsis: a prospective hospital-based study

BACKGROUND

Sepsis is still one of the main causes of infants and children mortality especially in developing, economically challenged countries with limited resources. Our objective in this study was to determine, the prognostic value of platelet count, mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (PCT) in critically ill infants and children with severe sepsis, as they are readily available biomarkers, that can guide clinicians during managing of severe sepsis.

METHODS

Sixty children were included; they were diagnosed with severe sepsis according to the international pediatric sepsis consensus conference criteria. At admission to Pediatric intensive care unit, complete blood count with platelet count and parameters (MPV, PDW and PCT) and C-reactive protein (CRP) level were determined for all children. Also, assessment of the Pediatric Risk of Mortality (PRISM III) score was done to all. These children were followed up till discharge from hospital or death. Accordingly, they were grouped into: (1) Survivor group: included 41 children. (2) Non-survivor group: included 19 children.

RESULTS

Platelet count and PCT were significantly lower (p < 0.001) and MPV was significantly higher in non-survivor than survivors (p = 0.004). MPV/PLT, MPV/PCT, PDW/PLT, PDW/PCT ratios were found to be significantly higher in the non-survivors than survivor (p < 0.001 in all). PCT with sensitivity = 94.74%, was the most sensitive platelet parameter for prediction of death, while MPV/PCT was the most sensitive ratio (sensitivity = 94.7%).

CONCLUSION

Thrombocytopenia, platelet indices and their ratios, especially plateletcrit and MPV/PCT, are readily available, sensitive, prognostic markers, that can identify the severe sepsis patients with poorest outcome.

The relationship between hand hygiene practices and nasal Staphylococcus aureus carriage in healthcare workers

Background:

The nasal carriage rate of Staphylococcus aureus in healthcare workers (HCWs) is higher than the general population. Their hands serve as vectors for transmitting S.aureus colonized in the nose to patients.

Objectives:

To determine the rate of nasal S.aureus carriage and methicillin resistance in HCWs and to evaluate the relationship between carriage and personal risk factors and hand hygiene behaviors.

Methods:

The questionnaire included questions about sociodemographic characteristics, occupational and personal risk factors for S.aureus carriage, the “Hand Hygiene Belief Scale (HHBS),” and “Hand Hygiene Practices Inventory (HHPI)”. Nasal culture was taken from all participants. Presence of S.aureus, methicillin and mupirocin resistance were investigated in samples.

Results:

The study was carried out with 269 HCWs. The prevalence of S.aureus carriage was 20.1% (n:54). Among 54 S.aureus carriers, only one person had MRSA (0.37%). All S.aureus isolates were susceptible to mupirocin. S.aureus carriage was found to be significantly lower in the smoker group (p:0.015) and in the personnel wearing gloves during the procedures of each patient (p:0.002). S.aureus culture positivity was found to decrease significantly with increasing handwashing frequency (p:0.003). The mean HHPI score was higher in women (p:0.001). The mean HHPI score was lower in the group with nasal carriers than in non-carriers (p:0.176).

Conclusion:

The knowledge of hand hygiene practices, high frequency of handwashing, and wearing different gloves during the procedure of each patient decrease S.aureus nasal carriage in HCWs. In addition mupirocin is still effective in nasal S.aureus carriers.

Screening of methicillin-resistant Staphylococcus aureus in healthcare workers and students and its susceptibility to mupirocin in a tertiary care teaching hospital in South India

BACKGROUND:

Staphylococcus is the most common pathogen causing infection in hospitals. They also colonize the healthcare workers who serve as reservoir of infection. Emergence of methicillin-resistant Staphylococcus aureus (MRSA) is a burning issue throughout the world contributing to significant morbidity and mortality. Use of mupirocin to eradicate the carrier state is the need of the hour.

OBJECTIVES:

To screen healthcare workers (HCWs) and medical students for MRSA and to know the susceptibility of mupirocin in this group.

MATERIALS AND METHODS:

A total of 432 students, nursing staff, doctors and house-keeping staff were screened for MRSA for 4 months. The MRSA and methicillin-resistant coagulase-negative Staphylococcus (MRCoNS) isolates were then tested for mupirocin resistance.

RESULTS:

Out of 432 samples, 24 (5.55%) were MRSA and 104 (24.07%) were MRCoNS. Only 4.16% (n = 1) showed high-level resistance to mupirocin among the MRSA isolates, while resistance among MRCoNS was higher at 6.7% (n = 7) for low-level resistance and 17.30% (n = 18) for high-level resistance.

CONCLUSION:

MRSA colonization of HCWs may serve as a source of infection and mupirocin resistance should be screened for all whether working in Intensive Care Units or not and if detected, alternative treatment should be used which will result in appropriate use of this antibiotic for decolonization.

Mupirocin resistance in Staphylococcus aureus: A systematic review and meta-analysis

OBJECTIVES

Staphylococcus aureus is one of the most common pathogens causing nosocomial and community-acquired infections associated with high morbidity and mortality. Mupirocin has been increasingly used for treatment of methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) infections. The aim of this study was to determine the prevalence of mupirocin-resistant S. aureus (MuRSA), mupirocin-resistant MRSA (MuRMRSA), high-level MuRSA (HLMuRSA) and high-level MuRMRSA (HLMuRMRSA) worldwide.

METHODS

Online databases including Medline, Embase and Web of Science were searched (2000-2018) to identify studies addressing the prevalence of MuRSA, MuRMRSA, HLMuRSA and HLMuRMRSA. STATA v. software was used to interpret the data.

RESULTS

Of the 2243 records identified from the databases, 30 and 63 studies fulfilled the eligibility criteria for MuRSA and MuRMRSA, respectively. Finally, 27 and 60 studies were included separately for HLMuRSA and HLMuRMRSA, respectively. The analyses revealed pooled and averaged prevalences of MuRSA, MuRMRSA, HLMuRSA and HLMuRMRSA of 7.6% [95% confidence interval (CI) 6.2-9.0%], 13.8% (95% CI 12.0-15.6%), 8.5% (95% CI 6.3-10.7%) and 8.1% (95% CI 6.8-9.4%), respectively.

CONCLUSION

Overall, these results show a global increase in the prevalence of HLMuRSA and HLMuRMRSA among clinical S. aureus isolates over time. However, there was only a significant increase in the prevalence of MuRMRSA compared with the other categories, especially MuRSA. Since mupirocin remains the most effective antibiotic for MSSA and MRSA decolonisation both in patients and healthcare personnel, a reduction of its effectiveness presents a risk for invasive infection. Monitoring of mupirocin resistance development remains critical.

Mitral Annular Plane Systolic Excursion as a Predictor of Mortality in Children With Septic Shock

OBJECTIVES

Myocardial dysfunction is well recognized in severe sepsis and septic shock. Echocardiography provides rapid, noninvasive, and bedside evaluation of cardiac function in patients with hemodynamic instability. Mitral annular plane systolic excursion is an M-mode-derived echocardiographic variable used to assess longitudinal left ventricular systolic function. No data are available about the uses of mitral annular plane systolic excursion in children with septic shock. Therefore, we aimed to assess the prognostic significance of mitral annular plane systolic excursion in children with septic shock and to correlate it with the most commonly used measures of left ventricular systolic function and myocardial injury.

DESIGN

A prospective cohort study.

SETTING

The study carried out at the PICU of Menoufia University Hospital in the period from March 2015 to September 2016.

PATIENTS

We serially enrolled 50 children with septic shock.

INTERVENTIONS

Complete diagnostic workup was performed for each patient including calculation of Pediatric Risk of Mortality III score. Transthoracic echocardiography was done to obtain mitral annular plane systolic excursion and the left ventricular ejection fraction measurement within 24 hours of inclusion then repeated on third and fifth days. Patients were followed up until hospital discharge or death. The predictive power of mitral annular plane systolic excursion was determined using the receiver operating characteristic curve.

MEASUREMENTS AND MAIN RESULTS

Mitral annular plane systolic excursion was significantly lower in nonsurvivors compared with survivors (p < 0.001). Receiver operating characteristic curve analysis showed an area under the curve of 0.892 for mitral annular plane systolic excursion on day 1. The cut-off point was 7.9 mm with 82.76% sensitivity and 80.95% specificity. Furthermore, follow-up of the patient's systolic function showed that mitral annular plane systolic excursion was significantly lower in nonsurvivors compared with survivors on days of follow-up, whereas left ventricular ejection fraction was not significantly different between survivors and nonsurvivors at any day. Mitral annular plane systolic excursion was positively correlated with left ventricular ejection fraction (p = 0.044) and duration of hospital stay (p < 0.001) and negatively correlated with Pediatric Risk of Mortality III score (p < 0.001) and cardiac troponin I level (p < 0.001).

CONCLUSIONS

Measurement of mitral annular plane systolic excursion at admission added a prognostic value in septic shock children. Compared with the left ventricular ejection fraction, longitudinal systolic function might be more sensitive in the detection of myocardial dysfunction in critically ill children and should receive more attention.

Effectiveness of provider strategies for the early recognition of clinical deterioration due to sepsis in pediatric patients: a systematic review protocol

REVIEW QUESTION

The objective of this review is to determine the effectiveness of provider strategies for the early recognition of clinical deterioration due to sepsis in pediatric patients. Specifically, the review question is: among pediatric, hospitalized patients, up to 18 years of age, what is the effectiveness of clinical assessment compared with use of early recognition screening tools for the recognition of clinical deterioration due to sepsis?

Vitamin D deficiency and clinical outcomes related to septic shock in children with critical illness: a systematic review

PURPOSE

Low vitamin D blood levels are related to many clinical outcomes in children with critically illness. However, the relationship of it and septic shock has not been systematically analyzed. The objective of this review was to evaluate the effect of vitamin D on septic shock and predict if vitamin D administration can improve prognosis of it.

MATERIALS AND METHODS

Online databases were searched up to June 1st, 2017 for studies on the relation of vitamin D deficiency (VDD) and clinical outcomes on septic shock in children with critical illness. The primary end point was the effect of VDD on occurrence of septic shock. The secondary endpoints were the association of VDD and clinical outcomes related to septic shock. We summarized the strength of association between VDD and each factor on septic shock. Individual factors were defined as strong, moderate, weak, or inconclusive according to the numbers of the article supporting the relation between them.

RESULTS

Eight studies published between 2012 and 2017, for a total of 1367 patients, were included in the final analysis. We extracted eight patient-level factors and among them one showed strong association of VDD and septic shock. Four factors demonstrated moderate or weak strength of evidence for it: nonresolution of shock, catecholamine refractory shock, fluid boluses, vasopressor use. But evidence for the association between VDD and severity of illness, stay of pediatric intensive care unit (PICU), are weak. Most of the articles showed no significant association between VDD and mortality.

CONCLUSIONS

Among critically ill children, VDD might be associated with the occurrence and resolution of septic shock. A larger multicenter trial could conclusively confirm these findings. Further research is also needed to identify vitamin D administration for better outcomes in pediatric patients.

Methicillin-resistant Staphylococcus aureus bacteremia among liver transplant recipients: epidemiology and associated risk factors for morbidity and mortality

Bacteremia due to Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), complicates the clinical course of liver transplantation and is associated with high morbidity and mortality. Intravascular catheters had been reported to be the most frequent source of MRSA bacteremia. Among bacteremic liver recipients, 26.3%-100% of S. aureus were MRSA. Previous studies identified pre-transplant and post-transplant acquired S. aureus carriage, greater severity of liver disease, hepatocellular carcinoma and infection with immuno-modulatory viruses as predictors of S. aureus bacteremia in liver recipients. MRSA bacteremia accompanied by pneumonia and abdominal infections was related to mortality. Vancomycin, as well as daptomycin, is a first-line antibiotic for MRSA bacteremia. The purpose of this review is to better understand the characteristics of MRSA bacteremia by summarizing the epidemiology and antimicrobial resistance of S. aureus, the primary source, and related risk factors for morbidity and mortality of MRSA bacteremia. We have also explored the diagnostic, therapeutic and preventive measures for MRSA bacteremia to improve the outcomes of liver recipients.

Staphylococcus epidermidis isolates from nares and prosthetic joint infections are mupirocin susceptible

The objective of the present study was to investigate the antibiotic susceptibility including mupirocin among Staphylococcus. epidermidis isolated from prosthetic joint infections (PJIs) (n=183) and nasal isolates (n=75) from patients intended to undergo prosthetic joint replacements. Susceptibility to mupirocin (used for eradication of nasal carriership of Staphylococcus aureus) was investigated by gradient test, and susceptibility to various other antimicrobial agents was investigated by disc diffusion test. All isolates, except three from PJIs and one from the nares, were fully susceptible to mupirocin. Multi-drug resistance (≥3 antibiotic classes) was found in 154/183 (84.2%) of the PJI isolates but only in 2/75 (2.7%) of the nares isolates, indicating that S. epidermidis causing PJIs do not originate from the nares.

Perioperative participation of orthopedic patients and surgical staff in a nasal decolonization intervention to reduce Staphylococcus spp surgical site infections

With the goal of reducing rates of surgical site infections in our spine patients, we initiated a trial to investigate the impact of adding perisurgical nasal decolonization involving patients and surgical and nursing staff. We combined immediate presurgical application of a nonantibiotic alcohol-based nasal antiseptic with existing chlorhexidine bath or wipes in a comprehensive pre- and postoperative decolonization protocol. Mean infection rates were significantly decreased by 81% from 1.76 to 0.33 per 100 surgeries during the 15-month trial, when compared with the prior 9-month baseline.

Predictors of mortality in a paediatric intensive care unit in Kigali, Rwanda

BACKGROUND

The enormous burden of critical illness in resource-limited settings has led to a growing interest in paediatric critical care in these regions. However, published data on the practice of critical care and patient outcomes in these settings are scant.

OBJECTIVE

This study sought to identify risk factors associated with mortality in the newly established Paediatric Intensive Care Unit (PICU) at Kigali University Teaching Hospital (KUTH) in Rwanda and test the predictive ability of a newly devised mortality risk score, the modified PRISM (MP) score.

METHODS

All admissions to the PICU at KUTH from October 2012 to October 2014 were included. Demographic and physiological data on each patient were gathered and each was assigned a MP score. This prospective cross-sectional study examined the association between the characteristics and physiological status of these patients and mortality. Using logistic regression, factors associated with mortality in the PICU were analysed.

RESULTS

A total of 213 children were admitted to the PICU during the study period. Three patients were excluded because of missing data. Of this total, 59% were male, 25% were neonates and nearly 60% were moderately to severely malnourished. The overall mortality rate was 50%. On bivariate analysis, factors associated with increased mortality were male sex, use of vasoactive medications, a MP score ≥ 5, a discharge diagnosis of septic shock, and malnutrition on admission. On multivariate analysis, only the use of vasoactive drugs [odds ratio (OR) 12.24, 95% confidence interval (CI) 4.4-35.4, p < 0.001] and MP score ≥ 5 (OR 16.1, CI 6.3-40.8, p < 0.001) were associated with mortality.

CONCLUSION

The observed mortality rate was in the range reported in other resource-limited settings. The initial attempt to create and implement a risk of mortality tool for this setting determined a score that could identify those patients at higher risk of mortality. In PICUs in resource-limited settings, the gathering of data and use of severity of illness tools could improve care in a number of ways.

Prevalence and genetic mechanisms of antimicrobial resistance in Staphylococcus species: A multicentre report of the indian council of medical research antimicrobial resistance surveillance network

PURPOSE

Routine surveillance of antimicrobial resistance (AMR) is an essential component of measures aimed to tackle the growing threat of resistant microbes in public health. This study presents a 1-year multicentre report on AMR in Staphylococcus species as part of Indian Council of Medical Research-AMR surveillance network.

MATERIALS AND METHODS

Staphylococcus species was routinely collected in the nodal and regional centres of the network and antimicrobial susceptibility testing was performed against a panel of antimicrobials. Minimum inhibitory concentration (MIC) values of vancomycin (VAN), daptomycin, tigecycline and linezolid (LNZ) against selected methicillin-resistant Staphylococcus aureus(MRSA) isolates were determined by E-test and MIC creep, if any, was determined. Resistant genotypes were determined by polymerase chain reaction for those isolates showing phenotypic resistance.

RESULTS

The prevalence of MRSA was found to be range from moderate (21%) to high (45%) among the centres with an overall prevalence of 37.3%. High prevalence of resistance was observed with commonly used antimicrobials such as ciprofloxacin and erythromycin in all the centres. Resistance to LNZ was not encountered except for a single case. Full-blown resistance to VAN in S. aureus was not observed; however, a few VAN-intermediate S. aureus isolates were documented. The most common species of coagulase negative staphylococci (CoNS) identified was Staphylococcus haemolyticus and Staphylococcus epidermidis. Resistance among CoNS was relatively higher than S. aureus. Most phenotypically resistant organisms possessed the corresponding resistance genes.

CONCLUSION

There were localised differences in the prevalence of resistance between the centres. The efficacy of the anti-MRSA antimicrobials was very high; however, almost all these antimicrobials showed evidence of creeping MIC.

Virulence and resistance profiles of MRSA isolates in pre- and post-liver transplantation patients using microarray

Methicillin-resistant Staphylococcus aureus (MRSA) screening plays a great role in preventing infections in surgical patients. This study aims to evaluate clonality, virulence and resistance of MRSA in pre- and post-liver transplantation (LT) patients. Nasal and groin swabs of 190 patients were collected. PCR for virulence genes and staphylococcal cassette chromosome mec (SCCmec) types, microarray, PFGE, multilocus sequence typing and MIC were performed. MRSA carriers were detected in 20.5 % (39/190) of the patients. However, only three colonized patients developed infections post-LT. Sixty-nine MRSA isolates were identified, and the most frequent SCCmec type was type II (29/69; 42.0 %). Most isolates (57/69; 82.6 %) were susceptible to trimethoprim-sulfamethoxazole (TMP/SMX) and harboured the lukD, lukE, clf and fnbA genes as determined by PCR. Five sequence types (ST) were identified among nine clones; 36.2 % (25/69) isolates belonged to a predominant clone (ST105 and SCCmec type II) that was susceptible to TMP/SMX, mupirocin and chlorhexidine, which had 87.9 % similarity with the New York/Japan clone. The array showed virulence difference in isolates of the same clone and patients and that colonized isolates (pre-LT patients) were less virulent than those post-LT and those infected. Therefore, despite the high frequency of MRSA colonization, infection due to MRSA was uncommon in our LT unit. MRSA isolates presented great diversity. Isolates of the same clone expressed different virulence factors by array. Colonizing isolates pre-LT expressed less virulent factors than post-LT and infecting isolates.

Investigation of biofilm formation ability, antimicrobial resistance and the staphylococcal cassette chromosome mec patterns of methicillin resistant Staphylococcus epidermidis with different sequence types isolated from children

This study investigated the molecular characterizations of 80 methicillin resistant Staphylococcus epidermidis (MRSE) collected during 2012-2013 in Tehran Children's Medical Center, Iran. About 90% of MRSE isolates were multi-drug resistant (MDR) and the highest resistance was observed to cotrimoxazole and they were quite sensitive to quinupristin-dalfopristin and linezolid. Though vanA gene was not detected, the majority of isolates showed intermediate resistance to vancomycin (MIC90 16 μg/ml). Resistance to mupirocin was observed in 18 isolates. Staphylococcal cassette chromosome mec (SCCmec) types V, III, IV and II were detected in 23.75%, 7.5%, 6.25% and 5% of isolates respectively, in some of which the additional parts of mec or ccr complexes were observed. In 57.5% MRSE isolates SCCmec types were not classified. 41.2% of MRSE isolates were carrying intercellular adhesion (ica) operon and 40% had strong or intermediate biofilm. The types of arginine catabolic mobile element (ACME) were limited to type I and II. Nine sequence types (STs) were seen in mupirocin resistant MRSE isolates. The common STs were ST2, ST5 and ST22 with 27.7% (5/18), 22.2% (4/18) and 16.6% (3/18) frequencies, respectively. ST23, ST54 and ST179 plus three novels STs 580, 581,588 were also observed. The majority of STs, 83.3% (15/18) belonged to clonal complex 2 (CC2). The spread of antibiotic resistance and virulence factors among MRSE species is an alarming sign in Children's Hospitals. The combination of these two issues leads to increase the chance of successfully establishing of common STs in hospital environments, and promotes the device-related infections and bacteremia.

Correlation of mupirocin resistance with biofilm production in methicillin-resistant Staphylococcus aureus from surgical site infections in a tertiary centre, Egypt

The aim of this study was to detect mupirocin-resistant isolates from pus/wound swabs taken postoperatively in a tertiary centre in Egypt and to determine their ability to form biofilm in order to establish its correlation with mupirocin resistance. This was a prospective study including 513pus/wound swabs from patients suffering from postoperative surgical site infections over the period July 2013-January 2015. Samples were cultured and isolates were identified by coagulase activity, DNase test, mannitol fermentation by mannitol salt agar followed by API Staph 32. Oxacillin agar screen test, agar dilution test for mupirocin, and mupA gene detection by PCR were performed for all methicillin-resistant Staphylococcus aureus (MRSA) isolates. Biofilm detection was carried out by the microtitre plate and Congo red agar methods. Of the 161 S. aureus isolates identified, 73 (45.3%) were MRSA, among which 82.2% were mupirocin-susceptible and 17.8% were mupirocin-resistant. Among the resistant isolates, 38.5% showed low-level resistance and 61.5% were high-level mupirocin-resistant. The mupA gene was detected in 75.0% of high-level mupirocin-resistant strains and in none of the low-level mupirocin-resistant strains. Among the mupirocin-susceptible isolates, 95.0% were biofilm-producers and 5.0% did not produce biofilm. All mupirocin-resistant isolates produced biofilm. Moreover, 15.3% of high-level mupirocin-resistant strains were negative for the mupA gene but showed evidence of biofilm formation. In conclusion, biofilm formation may be suggested to play a role in mupirocin resistance besides the presence of a genetic element encoding abnormal isoleucyl-tRNA synthetase, however further studies are needed to confirm these findings.

Mupirocin Resistance in Isolates of Staphylococcus spp. from Nasal Swabs in a Tertiary Hospital in France

Mupirocin is a topical antibiotic largely used to eradicate staphylococcal nasal carriage. Here, we investigated the prevalence of mupirocin-resistant Staphylococcus aureus and coagulase-negative staphylococcal isolates recovered from patients in different wards in a hospital (Lyon, France), which were determined both phenotypically with an Epsilometer test (Etest) and genetically by PCR for mupA and mupB.