Decolonization Treatment Research Articles

Carriage of methicillin-resistant Staphylococcus aureus in children

Decolonization treatment of MRSA carriers is recommended in Denmark, except in households with MRSA-positive children <2 years old (wait-and-see approach). To investigate a wait-and-see approach in children 2-5 years old, and the effect of decolonization treatment of MRSA carriage in all children <6 years old. In this retrospective follow-up study, we included MRSA carriers <6 years old in the Capital Region of Denmark from 2007 to 2021. Data were collected from laboratory information systems and electronic patient records. We divided children into age groups of <2 years or 2-5 years and decolonization treatment versus no treatment. Treatment was chlorhexidine body washes and nasal mupirocin, sometimes supplemented with systemic antibiotics. Children were followed until becoming MRSA free, or censoring. The probability of becoming MRSA free was investigated with Cox regression (higher HRs indicate faster decolonization). Of 348 included children, 226 were <2 years old [56/226 (25%) received treatment] and 122 were 2-5 years old [90/122 (74%) received treatment]. Multivariable analyses did not show a larger effect of decolonization treatment versus no treatment in <2-year-olds (HR 0.92, 95% CI 0.52-1.65) or 2-5-year-olds (HR 0.54, 95% CI 0.26-1.12). Without treatment, 2-5-year-olds tended to clear MRSA faster than <2-year-olds (HR 1.81, 95% CI 0.98-3.37). We did not find a larger effect of decolonization treatment versus no treatment in children <6 years old, and 2-5-year-olds tended to become MRSA free faster than <2-year-olds. These results support a wait-and-see approach for all children <6 years old, but further studies are needed.

Genetic Determinants in MRSA Carriage and Their Association with Decolonization Outcome

Methicillin-resistant Staphylococcus aureus (MRSA) colonization increases the risk of infection. Response to decolonization treatment is highly variable and determinants for successful decolonization or failure of eradication treatment are largely unknown. Insight into genetic predictors of eradication failure is potentially useful in clinical practice. The aim of this study was to explore genetic characteristics that are associated with MRSA decolonization failure. This cohort study was performed in a tertiary care hospital in the Netherlands. Patients with ≥ 1 positive MRSA culture from any site and with available whole -genome sequencing data of the MRSA isolate between 2017 and 2022 were included. Lineages, resistance, and virulence factors were stratified by MRSA decolonization outcome. In total, 56 patients were included: 12/56 (21%) with treatment failure and 44/56 (79%) with successful decolonization (with or without preceding treatment). A significant association was found between ciprofloxacin-resistant lineages and failure of eradication (OR 4.20, 95%CI 1.11–15.96, P = 0.04). Furthermore, livestock-associated MRSA and the major community-associated MRSA lineages ST6-t304 and ST8-t008 were associated with successful eradication treatment or spontaneous clearance. In conclusion, this explorative study showed a higher eradication failure rate in complicated MRSA carriers with ciprofloxacin-resistant MRSA lineages, which are predominantly healthcare-associated. Further studies are warranted to confirm the higher eradication failure risk of ciprofloxacin-resistant lineages, and identify the underlying mechanisms.

Identification of Vancomycin Resistance in Methicillin-resistant Staphylococcus aureus in two macaque species and decolonization and long-term prevention of recolonization in Cynomolgus Macaques (Macaca fascicularis).

Methicillin-resistant Staphylococcus aureus (MRSA) is a S. aureus strain with resistance to beta-lactam antibiotics, making it a global human and veterinary health concern. Specifically, immunosuppressed patients have a remarkably higher risk of clinical MRSA infections with significantly increased rates of prolonged clinical recovery, morbidity, and mortality. The current treatment of choice for MRSA is vancomycin. Importantly, we report the first known vancomycin-resistant S. aureus (VRSA) carriers in a cohort of Mauritian cynomolgus macaques (CM) imported to the Oregon National Primate Research Center (ONPRC), with a MRSA carrier rate of 76.9% (10/13 animals). All MRSA isolates also demonstrated resistance to vancomycin with prevalence of vancomycin-intermediate Staphylococcus aureus (VISA) at 30% (3/10 MRSA-positive CMs) and VRSA at 70% (7/10 MRSA-positive CMs). Additionally, we identified VRSA in a rhesus macaque (RM) housed within the same room as the VRSA-positive CMs and identified a MRSA/VISA carrier rate of 18.8% in RMs (3/16 positive for both MRSA and VISA) in unexposed recently assigned animals directly from the ONPRC RM breeding colony. Considering that the MRSA and VRSA/VISA-positive CMs future study aims included significant immunosuppression, MRSA/VRSA/VISA decolonization treatment and expanded "MRSA-free" practices were employed to maintain this status. We report the first controlled study using in-depth analyses with appropriate diagnostic serial testing to definitively show an MRSA decolonization therapy (90% success rate) and expanded barrier practice techniques to successfully prevent recolonization (100%) of a cohort of CMs MRSA-free (up to 529 days with a total of 4,806 MRSA-free NHP days).

The association between socioeconomic factors and the success of decolonization treatment among individuals diagnosed with methicillin-resistant Staphylococcus aureus: A cohort study from 2007 to 2020.

To examine associations between socioeconomic factors and (1) adherence to methicillin-resistant Staphylococcus aureus (MRSA) posttreatment follow-up swab sampling after 1 and 6 months and (2) successful decolonization treatment. Cohort study with 2 years of follow-up. Data on patients diagnosed with MRSA were extracted from a regional MRSA database and national registries. We used a cluster-based logistic regression model to estimate the adjusted odds ratios (aOR) and 95% confidence interval (CI) for associations between socioeconomic factors and decolonization treatment. Danish primary health care. The rate of adherence to posttreatment follow-up swab sampling among 2,536 cases 1 month after decolonization treatment was 66% (95% CI, 64%-68%), and it decreased to 30% (95% CI, 28%-32%) after 6 months. Living in intermediate municipalities (76-159 inhabitants/km2) or having retired were associated with completed posttreatment follow-up swabs 1 month after decolonization treatment: aOR, 1.40 (95% CI, 1.2-1.74) and aOR, 2.67 (95% CI, 1.16-6.13), respectively. The rate of successful decolonization treatment 2 years after initiating treatment was 36% (95% CI, 34%-38%). Factors associated with successful decolonization treatment included individuals with higher education (aOR, 1.62; 95% CI, 1.22-2.15), early retirees (aOR, 1.63; 95% CI, 1.12-2.38), those living in intermediate municipalities (ie, 160-900+ inhabitants/km2; aOR, 1.35; 95% CI, 1.08-1.68), and those living in predominantly urban municipalities (ie, 160-900+ inhabitants/km2; aOR, 2.04; 95% CI, 1.5-2.76). Disparities in the effect of decolonization treatment and adherence to MRSA follow-up sampling among MRSA-positive individuals appear to be largely explained by the level of education, area of residence, and employment status.

Success rates of MRSA decolonization and factors associated with failure

BackgroundWe evaluated the success rate of MRSA decolonization directly after treatment and after one year in patients who were treated at the outpatient MRSA clinic of a large university medical centre to identify potential contributing factors to treatment success and failure.MethodsData from November 1, 2013 to August 1, 2020 were used. Only patients who had undergone complete MRSA decolonization were included. Risk factors for MRSA treatment failure were identified using a multivariable logistic regression model.ResultsIn total, 127 MRSA carriers were included: 7 had uncomplicated carriage, 91 had complicated carriage, and 29 patients had complicated carriage in combination with an infection. In complicated carriers and complicated carriers with an infection final treatment was successful in 75.0%. Risk factors for initial treatment failure included having one or more comorbidities and not testing the household members. Risk factors for final treatment failure were living in a refugee centre, being of younger age (0–17 years), and having one or more comorbidities.ConclusionsThe results of this study indicate that patients with a refugee status and children treated at the paediatric clinic have a higher risk of MRSA decolonisation treatment failure. For this reason, it might be useful to revise decolonization strategies for these subgroups and to refer these patients to specialized outpatient clinics in order to achieve higher treatment success rates.

Exploring the Barriers in the Uptake of the Dutch MRSA 'Search and Destroy' Policy Using the Cascade of Care Approach.

The Dutch ‘search and destroy’ policy consists of screening patients with an increased risk of methicillin-resistant Staphylococcus aureus (MRSA) carriership and subsequent decolonization treatment when carriership is found. Decolonization therapy of individual MRSA carriers is effective. However, the effectiveness of the national ‘search and destroy’ policy is dependent on the entire cascade of care, including identification, referral, and subsequent treatment initiation in MRSA carriers. The aim of this study was to evaluate the leakages in the cascade of MRSA decolonization care. We assessed familiarity with the ‘search and destroy’ policy and the barriers in the uptake of MRSA eradication care using a questionnaire among 114 Dutch general practitioners. The main reasons for treatment were planned hospital visits, occupational reasons, and infections. The main reasons for refraining from eradication treatment were unfamiliarity with the ‘search and destroy’ policy and the assumption that MRSA carriership is often self-limiting. To optimize the continuity of the cascade of care, interventions should be aimed at supporting general practitioners and facilitating treatment and referral.

Estimated Roles of the Carrier and the Bacterial Strain When Methicillin-Resistant Staphylococcus aureus Decolonization Fails: a Case-Control Study.

ABSTRACTMethicillin-resistant Staphylococcus aureus (MRSA) is a common bacterial pathogen that frequently colonizes healthy individuals, with potential to cause invasive infection. In Denmark, to keep the prevalence low, MRSA carriers are recommended to undergo decolonization treatments, but achieving decolonization is challenging. Knowledge about the factors contributing to decolonization is scarce. We aimed to identify bacterial genome and clinical factors influencing MRSA decolonization. We identified all new MRSA patients above 2 years of age within the Hvidovre catchment area, Copenhagen, Denmark, in 2017 and 2018. Carriers were defined as chronic carriers (cases) if they were MRSA positive after two or more treatments and as nonchronic carriers (controls) if they were MRSA free after the first or second treatment. Using whole-genome sequencing (WGS), we constructed a pangenome of bacterial strains. With the incorporation of bacterial genome and clinical patient data, machine learning and multivariate analyses were performed to determine the factors associated with decolonization. A total of 477 MRSA carriers were included. An age of ≥13 years was significantly associated with nonchronic carriage. We identified 278 bacterial genetic features that were statistically significantly associated with chronic carriage (P < 0.05 by Fisher’s exact test). Chronic MRSA carriage was predicted with 68% accuracy using a combination of bacterial genome data and patient clinical data. Decolonization success is multifactorial. Apart from the 68% predicted accuracy found in this study, we estimate that the remaining 32% is a result of host factors and microbiome composition.IMPORTANCE Carriage of methicillin-resistant Staphylococcus aureus (MRSA) and other multiresistant bacteria is a prerequisite for infection and transmission. Successful decolonization treatment removes these risks. We aimed to identify bacterial genome and host clinical factors that influence MRSA decolonization to estimate the roles of the carrier and the bacterial strain, respectively, when decolonization fails. The long-term goal, beyond this study, is to optimize decolonization success, minimize MRSA transmission, and, ultimately, improve the quality of life of MRSA carriers.

A randomized, placebo-controlled, double-blinded trial of MRSA throat carriage treatment, with either standard decolonization alone or in combination with oral clindamycin

BackgroundStaphylococcus aureus is a frequent colonizer of the human skin and mucous membranes but can also cause a variety of serious infections. Antimicrobial resistance is an increasing worldwide challenge and is mainly driven by an overuse of antimicrobials. To avoid the spread of methicillin-resistant Staphylococcus aureus (MRSA) in Denmark, the Danish Health Authority recommends decolonization treatment of MRSA carriers and their household contacts. Standard decolonization treatment includes chlorhexidine body wash and mupirocin nasal ointment, especially throat carriage is difficult to treat. The broad-spectrum antibiotic, clindamycin, is often added to the decolonization treatment, but there is currently low scientific evidence for this treatment.AimTo investigate whether the addition of clindamycin to the standard decolonization treatment increases decolonization success in MRSA throat carriers.MethodsA randomized, placebo-controlled, double-blinded trial, including patients ≥ 18 years, who tested MRSA positive in the throat after completing one standard decolonization treatment. All carriers included in the trial receive standard decolonization treatment and are randomized to treatment with either placebo or clindamycin capsules for 10 days. We plan to include 40 participants in each of the two treatment arms.DiscussionDue to the lack of consistent scientific evidence of clindamycin’s effect in MRSA decolonization and the worldwide urgent need to reduce the use of antibiotics, we judged that a 30% increase in the decolonization success rate in carriers treated with clindamycin is appropriate to justify prescribing clindamycin as part of the decolonization treatment of asymptomatic MRSA carriers.Trial registrationEudraCT number 2019-002631-29

Scaling up Quality Improvement for Surgical Teams (QIST)\u2014avoiding surgical site infection and anaemia at the time of surgery: a cluster randomised controlled trial of the effectiveness of quality improvement collaboratives to introduce change in the NHS

BackgroundThe aim of this trial was to assess the effectiveness of quality improvement collaboratives to implement large-scale change in the National Health Service (NHS) in the UK, specifically for improving outcomes in patients undergoing primary, elective total hip or knee replacement.MethodsWe undertook a two-arm, cluster randomised controlled trial comparing the roll-out of two preoperative pathways: methicillin-sensitive Staphylococcus aureus (MSSA) decolonisation (infection arm) and anaemia screening and treatment (anaemia arm). NHS Trusts are public sector organisations that provide healthcare within a geographical area. NHS Trusts (n = 41) in England providing primary, elective total hip and knee replacements, but that did not have a preoperative anaemia screening or MSSA decolonisation pathway in place, were randomised to one of the two parallel collaboratives. Collaboratives took place from May 2018 to November 2019. Twenty-seven Trusts completed the trial (11 anaemia, 16 infection). Outcome data were collected for procedures performed between November 2018 and November 2019.Co-primary outcomes were perioperative blood transfusion (within 7 days of surgery) and deep surgical site infection (SSI) caused by MSSA (within 90 days post-surgery) for the anaemia and infection trial arms, respectively. Secondary outcomes were deep and superficial SSIs (any organism), length of hospital stay, critical care admissions and unplanned readmissions. Process measures included the proportion of eligible patients receiving each preoperative initiative.ResultsThere were 19,254 procedures from 27 NHS Trusts included in the results (6324 from 11 Trusts in the anaemia arm, 12,930 from 16 Trusts in the infection arm). There were no improvements observed for blood transfusion (anaemia arm 183 (2.9%); infection arm 302 (2.3%) transfusions; adjusted odds ratio 1.20, 95% CI 0.52–2.75, p = 0.67) or MSSA deep SSI (anaemia arm 8 (0.13%); infection arm 18 (0.14%); adjusted odds ratio 1.01, 95% CI 0.42–2.46, p = 0.98). There were no significant improvements in any secondary outcome. This is despite process measures showing the preoperative pathways were implemented for 73.7% and 61.1% of eligible procedures in the infection and anaemia arms, respectively.ConclusionsQuality improvement collaboratives did not result in improved patient outcomes in this trial; however, there was some evidence they may support successful implementation of new preoperative pathways in the NHS.Trial registrationProspectively registered on 15 February 2018, ISRCTN11085475

Efficacy of mupirocin, neomycin and octenidine for nasal Staphylococcus aureus decolonisation: a retrospective cohort study

BackgroundPeriprosthetic joint infection (PJI) causes significant morbidity. Methicillin sensitive Staphylococcus aureus (MSSA) is the most frequent organism, and the majority are endogenous. Decolonisation reduces PJIs but there is a paucity of evidence comparing treatments. Aims; compare 3 nasal decolonisation treatments at (1) achieving MSSA decolonisation, (2) preventing PJI.MethodsOur hospital prospectively collected data on our MSSA decolonisation programme since 2013, including; all MSSA carriers, treatment received, MSSA status at time of surgery and all PJIs. Prior to 2017 MSSA carriers received nasal mupirocin or neomycin, from August 2017 until August 2019 nasal octenidine was used.ResultsDuring the study period 15,958 primary hip and knee replacements were performed. 3200 (20.1%) were MSSA positive at preoperative screening and received decolonisation treatment, 698 mupirocin, 1210 neomycin and 1221 octenidine. Mupirocin (89.1%) and neomycin (90.9%) were more effective at decolonisation than octenidine (50.0%, P < 0.0001). There was no difference in PJI rates (P = 0.452).ConclusionsMupirocin and neomycin are more effective than octenidine at MSSA decolonisation. There was poor correlation between the MSSA status after treatment (on day of surgery) and PJI rates. Further research is needed to compare alternative MSSA decolonisation treatments.

Methicillin-resistant Staphylococcus aureus transmission and hospital-acquired bacteremia in a neonatal intensive care unit in Greece

BackgroundStaphylococcus aureus is a common pathogen causing hospital acquired infections (HAIs) in neonates. In this study, the epidemiology of methicillin-resistant S. aureus (MRSA) colonization and infections in a 30-bed, level III university-affiliated neonatal intensive care unit (NICU) located in a children's hospital was retrospectively investigated for the period 2014–2018. MethodsGenes encoding Panton-Valentine Leukocidin (lukS/lukF-PV, PVL), toxic shock syndrome toxin (tst), exfoliative toxins (eta, etb), and the resistance genes mecA, mecC and fusB, were defined in 46 representative strains by PCRs. Relatedness of strains was assessed by MLST. ResultsOf 1538 neonates, 77 (5%) had a positive culture for MRSA (23/77 were NICU-acquired and 54/77 imported cases). Four MRSA bacteremias occurred. Most isolates were multi-resistant. One major clone was identified, ST225, among 40 tested neonatal strains (23/40, 58%). Of these, 14/23 were imported from the same maternity hospital (MH). Another clone, ST217, was predominant (4/6) among health care workers (HCWs), found colonized. Four isolates classified as ST80 were PVL-positive. Additional four strains carried tst (10%), belonging to ST30 and ST225 (two strains each), and two etb. The implicated MH was notified for the problem, decolonization treatment was successfully performed in HCWs and neonates. Strengthening of infection control measures with emphasis on hand hygiene was applied. ConclusionsUncovering reservoirs for on-going MRSA transmission in NICUs has proved challenging. Well known nosocomial MRSA clones are being constantly introduced and transmitted via MHs and HCWs. Effective infection prevention and control requires constant vigilance.

Methicillin-Resistant Staphylococcus aureus Nasal Colonization Among Health Care Workers of a Tertiary Hospital in Ecuador and Associated Risk Factors.

BackgroundMethicillin-resistant Staphylococcus aureus (MRSA) is resistant to most of the commonly used antibiotics and is therefore a public health issue. Colonization with MRSA is a risk factor for infection or transmission.PurposeTo determine the prevalence of colonization with Staphylococcus aureus (SA) and MRSA strains in health care workers (HCWs) at a tertiary hospital in Ecuador and to determine the risk factors associated with carriage.MethodsOut of a cohort of 3800 HCWs, 481 individuals from different hospital departments were randomly selected, and a single nasal swab was collected. Detection of SA and MRSA was carried out with the LightCycler® MRSA Advanced Test. A questionnaire was performed that gathered demographic and occupational information of the participants to determine risk factors for MRSA colonization. Statistical analysis was performed with univariate and multivariate analysis and the R-software version 4.0.2.ResultsColonization with SA and MRSA occurred in respectively 23.7% (95% CI, 22.7–24.6) and 5% (95% CI, 3.39–7.58) of the individuals. The multivariate analysis showed that being older in age (OD 1.09) and being male (OD 2.78) were risk factors for SA and MRSA colonization (p-value < 0.001). Previous use of antibiotics or the use of nasal ointments diminished the colonization rates of SA (24% versus 3.7% and 10.1% respectively).ConclusionAbout 20% of the HCWs who were colonized with SA were colonized with MRSA, representing a risk for nosocomial infections and hospital outbreaks. Active monitoring and a decolonization treatment of the HCWs can reduce these risks.

Complicated Carriage with Methicillin-Resistant Staphylococcus aureus: Evaluation of the Effectiveness of Decolonization Regimens Advised in the Dutch National Guideline.

ABSTRACTMethicillin-resistant Staphylococcus aureus (MRSA) colonization leads to increased infection rates and mortality. Decolonization treatment has been proven to prevent infection and reduce transmission. As the optimal antimicrobial strategy is yet to be established, different regimens are currently prescribed to patients. This study aimed to evaluate the efficacy of the decolonization treatments recommended by the Dutch guideline. A retrospective multicenter cohort study was conducted in five Dutch hospitals. All patients who visited the outpatient clinic because of complicated MRSA carriage between 2014 and 2018 were included. We obtained data on patient characteristics, clinical and microbiological variables relevant for MRSA decolonization, environmental factors, decolonization regimen, and treatment outcome. The primary outcome was defined as three negative MRSA cultures after treatment completion. Outcomes were stratified for the first-line treatment strategies. A total of 131/224 patients were treated with systemic antibiotic agents. Treatment was successful in 111/131 (85%) patients. The success rate was highest in patients treated with doxycycline-rifampin (32/37; 86%), but the difference from any of the other regimens did not reach statistical significance. There was no difference in the success rate of a 7-day treatment compared to that with 10 to 14 days of treatment (odds ratio [OR], 0.99; 95% confidence interval [CI], 0.39 to 2.53; P = 1.00). Side effects were reported in 27/131 (21%) patients and consisted mainly of mild gastrointestinal complaints. In a multivariable analysis, an immunocompromised status was an independent risk factor for failure at the first treatment attempt (OR, 4.65; 95% CI, 1.25 to 17.25; P = 0.02). The antimicrobial combinations recommended to treat complicated MRSA carriage yielded high success rates. Prolonged treatment did not affect treatment outcome. A randomized trial is needed to resolve whether the most successful regimen in this study (doxycycline plus rifampin) is superior to other combinations.

Oral decontamination with colistin plus neomycin in solid organ transplant recipients colonized by multidrug-resistant Enterobacterales: a multicentre, randomized, controlled, open-label, parallel-group clinical trial

ObjectivesTo evaluate the efficacy of oral colistin-neomycin in preventing multidrug-resistant Enterobacterales (MDR-E) infections in solid organ transplant (SOT) recipients. MethodsMulticentre, open-label, parallel-group, controlled trial with balanced (1:1) randomization in five transplant units. SOT recipients were screened for MDR-E intestinal colonization (extended-spectrum β-lactamase or carbapenemase producing) before transplantation and +7 and + 14 days after transplantation and assigned 1:1 to receive treatment with colistin sulfate plus neomycin sulfate for 14 days (decolonization treatment (DT) group) or no treatment (no decolonization treatment (NDT) group). The primary outcome was diagnosis of an MDR-E infection. Safety outcomes were appearance of adverse effects, mainly diarrhoea, rash, nausea and vomiting. Patients were monitored weekly until 30 days after treatment. Intention-to-treat analysis was performed. ResultsMDR-E rectal colonization was assessed in 768 SOT recipients; 105 colonized patients were included in the clinical trial, 53 receiving DT and 52 NDT. No significant decrease in the risk of infection by MDR-E was observed in the DT group (9.4%, 5/53) compared to the NDT group (13.5%, 7/52) (relative risk 0.70; 95% confidence interval 0.24–2.08; p 0.517). Four patients (5.6%), three (5.6%) in the DT group and one (1.9%) in the NDT group, developed colistin resistance. Twelve patients (22.7%) in the DT group had diarrhoea, eight related to treatment (15.0%); one patient (1.8%) developed skin rash and another (1.8%) nausea and vomiting. Two patients (3.8%) in the NDT group developed diarrhoea. ConclusionsDT does not reduce MDR-E infections in SOT. Colistin resistance and adverse effects such as diarrhoea are a potential issue that must be taken seriously.

Outbreak of community-acquired Staphylococcus aureus skin infections in an Australian professional football team

ObjectivesSkin and soft tissue infections commonly affect athletes and can lead to cluster outbreaks if not managed appropriately. We report the findings of an investigation into an outbreak of community-acquired Staphylococcus aureus infection in an Australian professional football team. DesignRetrospective cross-sectional study. MethodsNose, axilla, groin and throat swab were collected from 47 participants. MRSA and MSSA isolates underwent antibiotic susceptibility testing, binary typing and whole genome sequencing. Infection control practitioners (ICPs) investigated the training grounds for risk factors in the transmission of S. aureus. ResultsAlmost half of the participants (n=23, 48.9%) were found to be colonised with MSSA. An outbreak cluster of MRSA ST5 closely related to the fusidic acid-resistant New Zealand NZAK3 clone was identified in a group of four players. MSSA ST15 and MSSA ST291 strains were found to have colonised and spread between two and five players, respectively. All participants were advised to undergo decolonisation treatment consisting of 4% chlorhexidine body wash and mupirocin nasal ointment for ten days. The ICP team identified several unhygienic practices within the club’s shared facilities that may have played a role in the transmission of S. aureus. ConclusionsWe report for the first time a community-associated S. aureus outbreak involving the highly successful fusidic acid-resistant MRSA ST5 clone in a professional football club associated with inadequate hygiene procedures. Management and prevention of S. aureus relies heavily on hygiene education and adherence to personal and environmental hygiene practices and policies.

Anti-adhesive activity of a Vaccinium corymbosum polyphenolic extract targeting intestinal colonization by Klebsiella pneumoniae

The therapeutic effect of Vaccinium polyphenols against uropathogens has been widely studied. Most attention has focused on the antimicrobial activity against P-fimbriated Escherichia coli strains. The present study investigated the anti-adhesive and anti-biofilm activity of a saline extract of blueberry (Vaccinium corymbosum) targeting intestinal colonization by a highly adherent Klebsiella pneumoniae strain. This strain, responsible for a large outbreak of infection in Spain, was selected on the basis of its remarkable capacity to colonize the gastrointestinal tract of patients.The blueberry extract was obtained using a medium scale ambient temperature system (MSAT) in a novel approach based on the use of an aqueous solvent and addition of mineral salts. The polyphenolic content was determined by liquid chromatography coupled to tandem mass-spectrometry (LC–MS/MS). The findings confirmed that the blueberry extract is a rich source of phenolic compounds, including the most polar polyphenols (mostly non-flavonoids), intermediate polarity compounds (flavan-3-ols and most procyanidins) and low polarity compounds (flavonols and anthocyanins). The extract significantly inhibited biofilm formation and bacterial adhesion to HT-29 colorectal cells by a highly adherent multidrug-resistant K. pneumoniae. Although some individual anthocyanidins (malvidin, delphinidin and cyanidin) and one hydroxycinnamic acid (caffeic acid) proved capable of reducing bacterial adhesion, the unfractionated extract was more active than any of the individual polyphenolic compounds. In addition, the extract displayed considerable potential as an intestinal decolonization treatment in a murine model. The study findings demonstrate the potential value of the V. corymbosum extract as an alternative treatment for K. pneumoniae infections.

Colonización nasal por Staphylococcus aureus resistente a la meticilina en pacientes sometidos a cirugía cardiovascular en un hospital universitario de Bogotá, Colombia

ResumenIntroducción. Staphylococcus aureus resistente a la meticilina (SARM) es un microorganismo que coloniza las fosas nasales y diferentes partes del cuerpo, lo cual se considera un factor de riesgo para adquirir infecciones invasivas, especialmente en pacientes sometidos a cirugía cardiovascular.Objetivo. Determinar la colonización nasal por SARM y establecer las características clínicas en pacientes programados para cirugía cardiovascular.Materiales y métodos. Se hizo un estudio descriptivo entre febrero y diciembre de 2015. Se incluyeron pacientes adultos programados para cirugía cardiovascular en el Hospital Universitario San Ignacio de Bogotá. La colonización se identificó mediante reacción en cadena de la polimerasa (Polymerase Chain Reaction, PCR) en tiempo real en muestras obtenidas mediante hisopados nasales. Los pacientes fueron descolonizados con mupirocina al 2,0 % intranasal dos veces al día y baños con gluconato de clorhexidina al 4 % del cuello hacía abajo durante cinco días, al cabo de lo cual se hizo una PCR de control. Resultados. Se incluyeron 141 pacientes, 52 hospitalizados y 89 ambulatorios. Del total, 19 (13,4 %) tenían colonización nasal por SARM, correspondientes a 9 (17,3 %) de los 52 hospitalizados y 10 (11,2 %) de los 89 ambulatorios. Todos los pacientes sometidos a descolonización tuvieron resultado negativo en la PCR al final del proceso y ninguno presentó infección del sitio operatorio por S. aureus.Conclusiones. Se demostró colonización nasal por SARM tanto en los pacientes hospitalizados como en los ambulatorios. La descolonización con mupirocina fue efectiva para erradicar el estado de portador a corto plazo, lo que podría tener efecto en las tasas de infección del sitio operatorio en las cirugías cardiovasculares.

Outpatient decolonization after recurrent skin infection with Panton-Valentine leukocidin (PVL)-producing S. aureus-The importance of treatment repetition.

BackgroundRecurrent skin abscesses are often associated with Panton-Valentine leukocidin-producing strains of S. aureus (PVL-SA). Decolonization measures are required along with treatment of active infections to prevent re-infection and spreading. Even though most PVL-SA patients are treated as outpatients, there are few studies that assess the effectiveness of outpatient topical decolonization in PVL-SA patients.MethodsWe assessed the results of topical decolonization of PVL-SA in a retrospective review of patient files and personal interviews. Successful decolonization was defined as the absence of any skin abscesses for at least 6 months after completion of the final decolonization treatment. Clinical and demographic data was assessed. An intention-to-treat protocol was used.ResultsOur cohort consisted of 115 symptomatic patients, 66% from PVL-positive MSSA and 19% from PVL-positive MRSA. The remaining 16% consisted of symptomatic patients with close contact to PVL-SA positive index patients but without detection of PVL-SA. The majority of patients were female (66%). The median age was 29.87% of the patients lived in multiple person households. Our results showed a 48% reduction in symptomatic PVL-SA cases after the first decolonization treatment. The results also showed that the decrease continued with each repeated decolonization treatment and reached 89% following the 5th treatment. A built multivariable Cox proportional-hazards model showed that the absence of PVL-SA detection (OR 2.0) and living in single person households (OR 2.4) were associated with an independently increased chance of successful decolonization.ConclusionIn our cohort, topical decolonization was a successful preventive measure for reducing the risk of PVL-SA skin abscesses in the outpatient setting. Special attention should be given to patients living in multiple person households because these settings could confer a risk that decolonization will not be successful.

Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen in erythrodermic cutaneous T-cell lymphoma (CTCL) patients.

Erythroderma can occur in cutaneous T-cell lymphoma (CTCL). Staphylococcus aureus (S. aureus) prevalence is increased in CTCL patients and contributes to CTCL disease flares. Our primary aim was to describe S. aureus infections, including resistance patterns and the antibiotic treatment regimens used, in erythrodermic CTCL patients. This was a retrospective chart review of erythrodermic CTCL patients who had S. aureus infection or colonization and were treated at the UT MD Anderson Cancer Center's Melanoma Skin Center between 2012 and 2016. Twenty-six erythrodermic CTCL patients had 50 documented S. aureus colonization or infection events. Patients had an improvement in body surface area (BSA) or modified Severity Weighted Assessment Tool (mSWAT) in 53% events treated for S. aureus. Seventeen of the 50 (34%) events were due to methicillin-resistant S. aureus (MRSA). One-third (33%) of MRSA events were initially treated with dicloxacillin. The MRSA isolates were sensitive to trimethoprim-sulfamethoxazole (92%) and doxycycline (88%). Patients treated in the outpatient setting (OR 0.073; 95% CI 0.008-0.627; p = 0.017) and patients with a previous history of topical anti-S. aureus decolonization treatments before S. aureus event as stand-alone (OR 0.125; 95% CI 0.018-0.887; p = 0.038) or in combination treatment with systemic antibiotics (OR 0.094; 95% CI 0.009-0.944; p = 0.045) were less likely to see improvement in BSA or mSWAT from S. aureus treatment. Treatment of S. aureus improved CTCL skin score in a high number of erythrodermic patients. The MRSA prevalence was high in erythrodermic CTCL patients. Clinicians should consider using empiric MRSA antibiotic coverage for these patients.

Methicillin-resistant Staphylococcus aureus carriers are vulnerable to bloodstream infection after living donor liver transplantation.

Bloodstream infection (BSI) is a life-threatening complication after living donor liver transplantation (LDLT). We aimed to explore the incidence and predisposing factors of BSI at our institution. We conducted a retrospective cohort analysis on all consecutive adults with BSI within 6months after LDLT performed between 2005 and 2016. For antimicrobial prophylaxis, ampicillin/sulbactam, cefotaxime, and micafungin were administered. From 2011, methicillin-resistant Staphylococcus aureus (MRSA) carriers were decolonized using mupirocin ointment and chlorhexidine gluconate soap. Risk factors for BSI were identified by uni- and multivariate logistic regression. Of a total of 106 LDLTs, 42 recipients (40%) suffered BSI. The BSI group demonstrated significantly higher in-hospital mortality rates compared with the non-BSI group (24% vs. 7%, P=.01). We identified MRSA carrier (odds ratio [OR], 19.1; P<.001), ABO incompatibility (OR, 2.9; P=.03), and estimated glomerular filtration rate <30mL/min/1.73m2 (OR, 15.8; P=.02) as independent risk factors for BSI. Decolonization treatment for MRSA carriers did not reduce the incidence of all-cause BSI but reduced the frequency of BSI caused by MRSA. To our knowledge, for the first time, MRSA carriers were revealed to be highly vulnerable to BSI after LDLT.