Methicillin-resistant Staphylococcus Aureus Infections In Patients Research Articles

Assessing the Concordance of MRSA Carriage Screening With MRSA Infections.

This study focused on children with confirmed methicillin-resistant Staphylococcus aureus (MRSA) infections to determine MRSA screening utility in guiding empirical anti-MRSA treatment of children without history of MRSA infection. We examined the concordance of screens to assess differences by infection type and used statistical analysis to determine significant contributors to concordance. Pediatric hospital patients admitted from 2002 through 2022 were included. Subjects had MRSA infections subsequent to MRSA surveillance screens performed the preceding year. Statistical analysis identified associations between MRSA screens and infections. Number needed to treat analysis calculated the utility of rescreening. Among 246 subjects, 39.0% had concordant screens; 151 (61.4%) screens were obtained in the 2 weeks preceding infection. Sensitivity for bacteremia was 50.0% (n = 42), for endotracheal/respiratory 44.4% (n = 81), and 29.4% (n = 102) for skin and soft-tissue infection. For children aged younger than 6 months, sensitivity was 35.9% (n = 78). Multivariable analysis significantly associated days since screening with decreasing likelihood of concordance. Regression modeled the probability of concordance to drop below 50.0% for all infections after 4 days, after 6 days for bacteremia specifically, and 12 days for endotracheal/respiratory infections. The concordance of screens was far lower than negative predictive values found previously; earlier studies were possibly impacted by low prevalence and exclusion of children at high risk to inform high negative predictive values. We suggest that negative MRSA screens should not invalidate reasonable suspicion for MRSA infection in patients with high pretest probabilities.

Population Pharmacokinetic and Pharmacodynamic Analysis for Maximizing the Effectiveness of Ceftobiprole in the Treatment of Severe Methicillin-Resistant Staphylococcal Infections.

Ceftobiprole is a fifth-generation cephalosporin used for different Gram-positive bacterial infections. A population pharmacokinetic analysis was conducted in real-life clinical patients to assess the adequacy of current dosages. Population pharmacokinetics was conducted using non-linear mixed effect modeling. Monte Carlo simulations were performed to determine the probability of target attainment (PTA) of free trough or steady-state concentration over MIC (fCtrough/MIC or fCss/MIC) ≥ 1 or ≥4 associated with both the standard and intensified dosing regimens adjusted for renal function. Cumulative fraction of response (CFR) against methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE) were also calculated. A total of 132 patients with 503 concentrations were included. Most of them (107/132, 81.1%) had hospital- or community-acquired pneumonia, endocarditis, and bacteremia. A three-compartment model adequately fitted ceftobiprole concentration-time data. Estimated glomerular filtration rate significantly affected drug clearance. Monte Carlo simulations showed that the optimal target of fCtrough/MIC or fCss/MIC ≥ 4 is achieved only with the use of the standard dosages administered by continuous infusion (CI) against MRSA infections in patients with preserved renal function. Intensified dosages administered by CI are needed in patients with impaired renal function and/or augmented renal clearance against MRSA and in patients with preserved renal functions against MRSE.

Transmission and microevolution of methicillin-resistant Staphylococcus aureus ST88 strain among patients, healthcare workers, and household contacts at a trauma and orthopedic ward.

Surgical sites infections (SSIs) caused by Methicillin-resistant Staphylococcus aureus (MRSA) constitute a major clinical problem. Understanding the transmission mode of MRSA is important for its prevention and control. We investigated the transmission mode of a MRSA outbreak in a trauma and orthopedic hospital ward. Clinical data were collected from patients (n = 9) with MRSA infection in a trauma and orthopedic ward from January 1, 2015 to December 31, 2019. The wards (n = 18), patients (n = 48), medical staff (n = 23), and their households (n = 5) were screened for MRSA. The transmission mode of MRSA isolates was investigated using next-generation sequencing and phylogenetic analyses. The resistance genes, plasmids, and single-nucleotide variants of the isolates were analyzed to evaluate microevolution of MRSA isolates causing SSIs. The MRSA colonization-positive doctor was asked to suspend his medical activities to stop MRSA spread. Nine MRSA infected patients were investigated, of which three patients were diagnosed with SSI and had prolonged hospitalization due to the persistent MRSA infection. After screening, MRSA isolates were not detected in environmental samples. The surgeon in charge of the patients with SSI caused by MRSA and his son were positive for MRSA colonization. The MRSA from the son was closely related to the isolates detected in MRSA-induced SSIs patients with 8-9 single-nucleotide variants, while ST88-MRSA isolates with three different spa types were detected in the surgeon's nasal cavity. Comparative genomic analysis showed that ST88-MRSA isolates acquired mutations in genes related to cell wall synthesis, colonization, metabolism, and virulence during their transmission. Suspending the medical activity of this surgeon interrupted the spread of MRSA infection in this ward. Community-associated MRSA clones can invade hospitals and cause severe postoperative nosocomial infections. Further MRSA surveillance in the households of health workers may prevent the transition of MRSA from colonization to infection.

Evaluating linezolid dose regimens against methicillin-resistant Staphylococcus aureus based on renal function in populations with different body weight.

Linezolid is an alternative first-line agent for MRSA pneumonia. This study assessed whether dose adjustments of linezolid against methicillin-resistant Staphylococcus aureus (MRSA) infections were needed based on renal function in populations with different body weight. Monte Carlo simulations were conducted to evaluate renal function in relation to the probability of target attainment (PTA) in three population groups with different body weight. Area under the concentration time curve (AUC)/ minimum inhibitory concentration (MIC) ratio and percentage of time above the MIC (%T > MIC) were regarded as pharmacokinetic/pharmacodynamic targets. The PTA and cumulative fractions of response (CFR) were calculated to assess the efficacy. Regarding safety, trough plasma concentration (Cmin ) > 8mg/L was used as target for toxicity. Using AUC/MIC >100 as the target pharmacodynamic (PD) index, the CFR of linezolid at the standard dose (600 mg every 12 h [q12h]) were 57.01%, 93.22%, and 99.93% in patients with normal renal function, patients with renal dysfunction and low body weight patients with renal dysfunction, respectively. Using 100%T> MIC as the target PD index, all the CFR of three population groups were more than 90% at the standard dose. The percentages of Cmin > 8mg/L at the standard dose of linezolid were 24.16%, 53.24%, and 90.10% in three population groups on day 7. The risk of thrombocytopenia of linezolid was extremely higher in low body weight patients with renal impairment when receiving standard linezolid dose compared with patients with normal renal function. 450 mg q12h and 300 mg q12h might be effective and safe against MRSA infection in patients with renal dysfunction and low body weight patients with renal dysfunction, respectively.

Evaluation of the impact of nasal colonization with methicillin-resistant Staphylococcus aureus on left ventricular assist device infections.

In this retrospective cohort study, we evaluated the predictive value of methicillin-resistant Staphylococcus aureus (MRSA) nasal swabs for the development of MRSA infections in patients with left ventricular assist devices. In 106 patients, the MRSA nasal swab had a negative predictive value of 92.9% demonstrating a potential role in antibiotic de-escalation.

Does the removal of contact precautions for MRSA and VRE infected patients change health care-associated infection rate?: A systematic review and meta-analysis

Update existing meta-analysis to analyze if discontinuation of contact precautions (CPs) for Methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin resistant Enterococcus (VRE) colonization or infection affects hospital-associated MRSA or VRE infection rates. We conducted a systematic review of 17 studies evaluating discontinuation of CPs for MRSA and VRE. Random-effects and fixed-effects models were used to determine the pooled risk ratios (RR) of preincidence hospital-associated infection rate to postincidence rate. Subgroup analysis was used to assess sources of heterogeneity. No significant difference between rates of hospital-associated MRSA infection before and after stopping the CPs was observed (RR, 0.84; 95% confidence internal [CI], 0.71-1.01; P = .06). An inverse association was observed between discontinuation of CPs and rates of hospital-associated VRE infection (RR, 0.82; 95% CI, 0.72-0.94; P = .005). A subgroup analysis of 6 studies that used chlorhexidine, showed no difference between rates of hospital-associated MRSA infection with discontinuation of CPs (RR, 0.83; 95% CI, 0.69-1.00; P = .05). In 5 studies that did not use chlorhexidine, there was no difference between rates of hospital-associated MRSA infection with discontinuation of CPs (RR, 1.02; 95% CI, 0.55-1.88; P= .95). There was no significant difference in rates of hospital-associated MRSA infection before and after removing CPs. Additionally, there were decreased rates of hospital-associated VRE infection following stoppage of CPs.

Methicillin-Resistant Staphylococcus aureus Prevalence Among Healthcare Workers in Contact Tracings in a Dutch Hospital

Background: In The Netherlands, the national guidelines on Methicillin-Resistant Staphylococcus aureus (MRSA) prevention and control advocate screening of healthcare workers (HCWs) after unprotected exposure to MRSA carriers. Although this strategy is largely successful, contact tracing of staff is a time-consuming and costly component. We evaluated our contact tracing policy for HCWs over the years 2010–2018. Methods: A retrospective, observational study was performed in a Dutch teaching hospital. All HCWs who had unprotected contact with an MRSA carrier were included in contact tracing. When there had been a long period of unprotected admission prior to an MRSA finding, or when the index case was an HCW, the entire (nursing) team was tested. All samples of HCWs who were tested for MRSA carriage as part of contact tracing from 2010 until 2018 were included. A pooled nose, throat, and perineum swab was collected using the eSwab medium (Copan) and inoculated on chromID MRSA agar plates (bioMérieux) after enrichment in a broth. Molecular typing was performed using multiple-locus variable number of tandem repeat analysis (MLVA). Results: In total, we included 8,849 samples (range, 677–1,448 samples per year) from 287 contact tracings (range, 26–55 contact tracings per year). Overall, 32 HCWs were colonized with MRSA (0.36%; 95% CI, 0.26%–0.51%). None of them developed a clinical infection. Moreover, 8 HCWs (0.10%; 95% CI, 0.05%–0.19%) were colonized with the same MLVA type as the index case and were detected in 6 of 287 contact tracings (2%). In 4 of 8 of these cases, a positive HCW was the index for undertaking contact tracing. In 3 of 8 cases, it was clear that the HCW who was identified in the contact tracing was the source of the outbreak and was the cause of invasive MRSA infections in patients. Notably, a different MLVA type as the index case was found in 24 HCWs (0.27%; 95% CI, 0.18%–0.40%) of whom 7 of 24 HCWs (29.2%) were intermittent carriers. Conclusions: This study revealed a sustained low MRSA prevalence among samples in contact tracing of HCWs over 9 years. Furthermore, it shows that when MRSA contact tracing is performed according to the national guideline, only 1 of 1,000 samples results in a secondary case. This is similar to the population carriage rate of MRSA in The Netherlands. More frequently, an unrelated strain is found. These findings raise questions regarding the efficacy of the current strategy to perform contact tracing after unprotected exposure.Funding: NoneDisclosures: None

Methicillin-Resistant Staphylococcus aureus Infections in Patients With Renal Disorders: A Review

Methicillin-resistant Staphylococcus aureus (MRSA) infection is a rapidly escalating global health burden. It is not only restricted to patients in the hospital settings but has also rooted deeply in the community settings. With increasing prevalence of life style and kidney diseases, the prevalence of MRSA infections is also expected to rise. MRSA infection plays a major role in renal disorders due to its direct vascular access (VA) thereby making patients undergoing dialysis and renal transplant more vulnerable to infections. Prolonged hospital stay, close proximity to MRSA-infected individual, exposure to broad-spectrum antibiotics, surgery and presence of foreign bodies such as central venous catheters predispose an individual to MRSA infection. Current panel of antibiotic treatment includes vancomycin, teicoplanin, linezolid, daptomycin, tigecycline and ceftaroline. However, emergence of resistant strains and several undesirable features pertaining to safety and tolerability of these drugs have led to limited options available for the management of multidrug-resistant MRSA infection in patients with renal disorders. Therefore, there is an increasing need for developing a new potent antibacterial agent with established renal safety that decreases the mortality and morbidity rates in MRSA-infected renal patients. World J Nephrol Urol. 2019;8(1):8-13 doi: https://doi.org/10.14740/wjnu384

Virulence Potential of Staphylococcus aureus Strains Isolated from Diabetic Foot Ulcers Among Patients from Southern Poland.

The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) was investigated among infected diabetic foot ulcers in hospitalized and nonhospitalized patients in southern Poland to assess the virulence patterns and antimicrobial resistance among these strains. MRSA was detected in 10.3% of all studied isolates, from the hospitalized patients only. The rest of the isolates was methicillin susceptible. The minimal inhibitory concentration that inhibits 50% of bacterial isolates (MIC50) for vancomycin was 1.0 mg/mL. The mupA gene was detected in six (8.8%) isolates, in one MRSA strain and five methicillin-sensitive S. aureus (MSSA) strains. Among the mupA-positive strains, two were resistant to mupirocin (1 MRSA and 1 MSSA). Such results raise serious concern about the usage of mupirocin in MRSA decolonization. The pvl gene was not detected among the study isolates. The majority of isolates (70.6%) possessed the lukE gene, with no significant difference in prevalence between MRSA and MSSA isolates. An interesting finding was the presence of enterotoxin genes among the study isolates. Diabetic foot may therefore be a reservoir of bacteria, containing genes localized on mobile genetic elements that could be easily transferred to other non-pathogenic strains. The prevalence of MRSA was alarmingly high (as also suggested by others), as evaluated by the presence of the mup gene among strains, highlighting the importance of appropriate clinical management of MRSA infections in patients with diabetic foot ulcers. In this group of patients, screening of ulcer samples before antimicrobial therapy would enable informed choices regarding the selection of antimicrobial agents (e.g. octenidine, authorized for the treatment of chronic wounds) maximizing the chances of positive therapy.

Risk of MRSA Infection in Patients with Intermittent versus Persistent MRSA Nares Colonization.

To determine the relative risk of invasive methicillin-resistant Staphylococcus aureus (MRSA) infection among non-colonized (NC) patients, intermittently colonized (IC) patients, and persistently colonized (PC) patients. Observational cohort study of patient data collected longitudinally over a 41-month period. Department of Veterans Affairs Eastern Colorado Healthcare System, a tertiary care medical center. Any patient who received ≥5 MRSA nasal swab tests between February 20, 2010, and July 26, 2013. In total, 3,872 patients met these criteria, 0 were excluded, 95% were male, 71% were white, and the mean age was 62.9 years on the date of study entry. Patients were divided into cohorts based on MRSA colonization status. Physicians reviewed medical records to identify invasive infection and were blinded to colonization status. Cox and Kaplan-Meier analyses were used to assess the relationship between colonization status and invasive infection. In total, 102 patients developed invasive MRSA infections, 16.3% of these were PC patients, 11.2% of these were IC patients, and 0.5% of these were NC patients. PC patients were at higher risk of invasive infection than NC patients (hazard ratio [HR] 36.8; 95% CI, 18.4-73.6; P<.001). IC patients were also at higher risk than NC patients (HR, 22.8; 95% CI, 13.3-39.3; P<.001). The difference in risk between PC and IC patients was not statistically significant (HR, 1.61; 95% CI, 0.94-2.78, P=.084). Alternate analysis methods confirmed these results. The risk of invasive MRSA infection is much higher among PC and IC patients, supporting routine clinical testing for colonization. However, this risk is similar among PC and IC patients, suggesting that distinguishing between the 2 colonization states may not be clinically important.

Risk Factors for Intensive Care Unit Acquired Nasal Colonization of MRSA and Its Impact on MRSA Infection

We aimed to determine the risk factors of methicillin-resistant Staphylococcus aureus (MRSA) colonization, and the impact of colonization on MRSA infection to evaluate the necessity of MRSA survey program in intensive care units (ICUs) in Turkey. The patients hospitalized in medical and neurosurgical ICUs longer than 24 hr were included into the study. To determine anterior nares MRSA colonization, swabs were taken from each patient in the first 48 hr, and followed by once a week till discharge from ICUs. During the one-year follow-up period, the number of the hospitalized patients who spent more than 24 hr in ICUs was 195 of 372 and 85 of 619 in medical and neurosurgical ICUs, respectively. Totally, 23 out of 280 patients (14 from medical ICU, 9 from neurosurgical ICU) were colonized with MRSA, and 11 out of 23 colonized patients were accepted as ICU-acquired infection. The duration of ICU hospitalization in patients with ICU-acquired MRSA colonization was found to be longer than the noncolonized patients (18 days vs. 8 days, P value < 0.001). The presence of gastrostomy and femoral catheter were determined as risk factors for ICU-acquired MRSA colonization. The percentages of MRSA infection in patients with and without MRSA colonized were 8.6% and 1.1%, respectively (P value: 0.009). The presence of gastrostomy and femoral catheter, and the duration of ICU hospitalization were found to be related with ICU-acquired MRSA colonization. Also, MRSA nares colonization increased the rates of both MRSA infection and ICU hospitalization.

Population Pharmacokinetic Analysis of Linezolid in Low Body Weight Patients with Renal Dysfunction

Linezolid has antibacterial activity against aerobic Gram-positive cocci, including methicillin-resistant Staphylococcus aureus (MRSA). Adjustment of the dose of linezolid has been proposed to be unnecessary in patients with reduced renal function. However, platelet counts and hemoglobin levels were shown to be significantly lower in such patients than in patients with normal renal function. The population pharmacokinetic (PPK) of linezolid was investigated in MRSA infected patients with renal dysfunction. Linezolid concentrations in serum were measured by high-performance liquid chromatography. PPK analysis was performed in the nonlinear mixed effects model (NONMEM) computer program. In the final PPK model, total body weight (TBW), estimated glomerular filtration rate (eGFR), hemoglobin (HB), and alanine amino transferase (ALT) were influential covariates on total body clearance (CL), and the volume of distribution (Vd) was affected by TBW, which was expressed as CL (L/h) = 0.00327 × TBW × eGFR(0.428) × HB(0.502) × 0.283 (ALT ≥ 100 IU/L) and CL (L/h) = 0.00327 × TBW × eGFR(0.428) × HB(0.502) (ALT < 100 IU/L), Vd (L) = 1.310 × TBW. The PPK parameters of linezolid obtained here are useful for the optimal use of linezolid with similar patient population characteristics.

Risk factors for development of methicillin-resistant Staphylococcus aureus infection among colonized patients

This study was conducted to identify clinical factors associated with development of infection caused by methicillin-resistant Staphylococcus aureus (MRSA) among hospitalized patients with nasal MRSA colonization. We conducted a prospective cohort with nested case-control study at a 672-bed, public, academic hospital in Dallas, Texas. The study duration was from January 1, 2008, to July 28, 2009. From the cohort of patients who had presence of nasal colonization with MRSA at admission, we identified patients who developed subsequent infection with MRSA during a 3-month period. We compared these patients (cases) with colonized patients who remained uninfected (controls; 2 controls per case). We collected demographic and clinical data and performed statistical analyses. During the 19-month study period, 426 patients were found to have nasal colonization with MRSA. Of these, 36 (8.5%) developed a subsequent infection with MRSA within 3 months. When these 36 cases were compared with 72 controls, the factors independently associated with the development of subsequent infection were development of pressure ulcer during hospital stay (adjusted odds ratio, 5.82; 95% confidence interval: 2.21-15.31; P value=.000) and preadmission steroid therapy (adjusted odds ratio, 13.2; 95% confidence interval: 2.44-70.97; P value=.003). History of steroid therapy prior to admission and development of pressure ulcer are associated with increased risk of subsequent MRSA infection in patients nasally colonized with MRSA.

The Efficacy and Safety of Arbekacin and Vancomycin for the Treatment in Skin and Soft Tissue MRSA Infection: Preliminary Study

BackgroundMethicillin-resistant Staphylococcus aureus (MRSA) has become a one of the most important causes of nosocomial infections, and use of vancomycin for the treatment of MRSA infection has increased. Unfortunately, vancomycin-resistant enterococcus have been reported, as well as vancomycin-resistant S. aureus. Arbekacin is an antibacterial agent and belongs to the aminoglycoside family of antibiotics. It was introduced to treat MRSA infection. We studied the clinical and bacteriological efficacy and safety of arbekacin compared to vancomycin in the treatment of infections caused by MRSA.Materials and MethodsThis was a retrospective case-control study of patients who were admitted to tertiary Hospital from January 1st, 2009 to December 31st, 2010, and received the antibiotics arbekacin or vancomycin. All the skin and soft tissue MRSA infected patients who received arbekacin or vancomycin were enrolled during the study period. The bacteriological efficacy response (BER) was classified with improved and failure. The improved BER was defined as no growth of MRSA, where failure was defined as growth of MRSA, culture at the end of therapy or during treatment. Clinical efficacy response (CER) was classified as improved and failure. Improved CER was defined as resolution or reduction of the majority of signs and symptoms related to the original infection. Failure was defined as no resolution and no reduction of majority of the signs and symptoms, or worsening of one or more signs and symptoms, or new symptoms or signs associated with the original infection or a new infection.ResultsTotally, 122 patients (63/99 in arbekacin, 59/168 in vancomycin group) with skin and soft tissue infection who recieved arbekacin or vancomcyin at least 4 days were enrolled and analysed. The bacteriological efficacy response [improved, arbekacin vs vancomycin; 73.0% (46/63), 95% confidence interval (CI) 60.3 to 83.4% vs 83.1% (49/59), 95% CI 71.0 to 91.6%] and clinical efficacy response [improved, arbekacin vs vancomycin; 67.2% (41/61), 95% CI 52.0 to 76.7% vs 78.0% (46/59), 95% CI 65.3 to 87.7%] were similar between the two groups (P=0.264, 0.265). The complication rate was significantly higher in the vancomycin group [29/59(49.2%), 95% CI 35.9 to 62.5%] than arbekacin [10/63(15.9%), 95% CI 8.4 to 29.0%] (P<0.001).ConclusionsArbekacin could be considered as an alternative antibiotics for vancomycin in skin and soft tissue infection with MRSA. However, further prospective randomized trials are needed to confirm this finding.

A negative nares screen in combination with absence of clinical risk factors can be used to identify patients with very low likelihood of methicillin-resistant Staphylococcus aureus infection in a Veterans Affairs hospital

Screening for nares carriage of methicillin-resistant Staphylococcus aureus (MRSA) could be used to identify patients at reduced risk for MRSA infection. However, recent studies suggest that negative results of nares surveillance testing are not reliable to predict a low risk for MRSA infection. To derive a clinical prediction rule, logistic regression was performed to identify predictors of MRSA infection in patients with negative nares surveillance results. To validate the prediction rule and modifications of the rule, the sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated in a prospective cohort of inpatients receiving empiric vancomycin. A prediction rule that included 8 clinical risk factors and nares surveillance results was sensitive with NPV of 99.9%. In the validation cohort, 43 of 451 (10%) patients receiving empiric vancomycin had MRSA infection. In comparison with nares surveillance results (sensitivity, 72%; NPV, 96%), the prediction rule was more reliable for prediction of low risk for MRSA infection (sensitivity, 93%; NPV, 98%). A modified rule that included additional indications for empiric MRSA coverage based on practice guidelines reliably predicted MRSA infection (sensitivity, 100%) while excluding those at low risk (NPV, 100%). Negative nares screening results in combination with absence of certain clinical risk factors or syndromes could provide a useful strategy to predict patients with low likelihood of MRSA infection.

Association of nutritional status, plasma, albumin levels and pulmonary function in cystic fibrosis.

Malnutrition is related with pulmonary disease. The aim was to analyze the association of lung function respectively to nutritional status, identified pulmonary pathogens and socioeconomic condition of patients attending a pediatric CF reference center. Cross-sectional study performed with CF patients aged 6 to 18 years attending a CF-Center in southern Brazil. Nutritional status, plasma albumin level and pulmonary bacterial colonization were assessed. The outcome studied was forced expiratory volume in 1 second (FEV1). Eighty-five patients were included in this study. FEV1 was significantly associated with body mass index (BMI) percentiles, plasma albumin level and methicillin resistant Staphylococcus aureus (MRSA) pulmonary colonization. Regression analysis showed that BMI below the 10th percentile was associated with a 25.58% drop in FEV1, and plasma albumin levels equal to or lower than 4.1 mg/dL was associated with 18.6% FEV1 reduction. FEV1 was 14.4% lower in the MRSA infected patients. Plasma albumin of 4.25 mg/dL predicted FEV1 of 60% with 76.9% sensitivity and 72.2% specificity, and 85.7% accuracy. The socioeconomic status was not association with pulmonary function. BMI below the 10th percentile and albumin below 4.1 mg/dL were predictors of low FEV1. Chronic MRSA infection was associated with lower FEV1. Longitudinal studies may better complement these results.

Asociación entre el estado nutricional, niveles de albúmina plasmática y función pulmonar en pacientes con fibrosis quística

Background & aims: Malnutrition is related with pulmonary disease. The aim was to analyze the association of lung function respectively to nutritional status, identified pulmonary pathogens and socioeconomic condition of patients attending a pediatric CF reference center. Methods: Cross-sectional study performed with CF patients aged 6 to 18 years attending a CF-Center in southern Brazil. Nutritional status, plasma albumin level and pulmonary bacterial colonization were assessed. The outcome studied was forced expiratory volume in 1 second (FEV1). Results: Eighty-five patients were included in this study. FEV1 was significantly associated with body mass index (BMI) percentiles, plasma albumin level and methicillin resistant Staphylococcus aureus (MRSA) pulmonary colonization. Regression analysis showed that BMI below the 10th percentile was associated with a 25.58% drop in FEV1, and plasma albumin levels equal to or lower than 4.1 mg/dL was associated with 18.6% FEV1 reduction. FEV1 was 14.4% lower in the MRSA infected patients. Plasma albumin of 4.25 mg/dL predicted FEV1 of 60% with 76.9% sensitivity and 72.2% specificity, and 85.7% accuracy. The socioeconomic status was not association with pulmonary function. Conclusion: BMI below the 10th percentile and albumin below 4.1 mg/dL were predictors of low FEV1. Chronic MRSA infection was associated with lower FEV1. Longitudinal studies may better complement these results.

Community‐acquired Staphylococcus aureus pneumonia among hospitalized children in Hawaii

Invasive community acquired (CA) Staphylococcus aureus (SA) disease has been endemically observed in Hawaiian children. We wanted to evaluate the clinical, laboratory findings, and outcomes of methicillin-resistant SA (MRSA) and methicillin-susceptible SA (MSSA) associated pneumonia admissions. We performed retrospective chart reviews of 38 culture proven SA pneumonia patients admitted to a pediatric tertiary medical center in Hawaii between January 1996 to December 2007. Twenty-six patients (68%) had MRSA and 12 patients (32%) had MSSA infection. The mean age of MRSA patients was 2.8 and 6.7 years for MSSA patients (P < 0.05). Pacific Islander and Native Hawaiian patients were affected disproportionately compared to non-Pacific Islander and Hawaiian groups (P < 0.0001). Demographic data, days of fever, tachypnea, hypoxia, and length of stay (LOS) were not significantly different between MRSA and MSSA infected patients. The mean LOS was 26.2 days (range 6-138 days); mean length of fever was 12.4 days. Seventy five percent (15 of 20) of patients who required intubation had MRSA. Twenty-one of the 29 (72%) total patients with pleural effusions had MRSA infection and all required chest tube placements. Two (5%) patients died; both had MRSA infection. Younger Pacific Islander/Native Hawaiian children were affected disproportionately and had MRSA infection more frequently. MRSA infected patients appeared to have severe disease with frequent chest tube placement, intubation, and fatality. Overall, both MRSA and MSSA pneumonia resulted in prolonged hospitalization, multiple complications, and significant healthcare costs.

Panton–Valentine leukocidin‐positive methicillin‐resistant Staphylococcus aureus infections in children with cancer

New strains of methicillin-resistant Staphylococcus aureus (MRSA) which frequently carry the Panton-Valentine leukocidin (PVL) genes have been recognized to cause invasive infections in otherwise healthy children and adults. However, the epidemiology of PVL-positive MRSA infections has not been described in children or adults with cancer. The epidemiology of MRSA infections in patients with cancer was retrospectively studied from 2000 to 2007. Molecular typing was performed by polymerase chain reaction (PCR) for the detection of the PVL genes. Staphylococcus cassette chromosome (SCC) mec and spa typing was performed on all PVL-positive isolates. A total of 88 MRSA isolates from clinically distinct infectious episodes were collected from 88 patients with cancer during the 8-year study period. Infections were predominant in the skin and soft tissues (SSTI; P = 0.0003). PVL-positive isolates, bearing the type IV SCCmec element, encoding the gene for methicillin resistance, increased significantly during this period (P = 0.043) and comprised 35 of 88 (40%) MRSA isolates. Of these 35 isolates, 32 belonged to spa type 8 and were USA300 genotype. Patients infected with PVL-positive strains did not have more SSTI (P = 0.166) or bacteremia (P = 0.510) as compared to patients with PVL-negative strains. A greater percentage of PVL-positive isolates were susceptible to ciprofloxacin (P = 0.006). PVL-positive MRSA infections are not associated with a higher morbidity as compared to PVL-negative MRSA infections in children with cancer.

Community-Acquired Methicillin-Resistant Staphylococcus Aureus in the Suburban Hand Surgery Patient Population

Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause for patients to present to a physician's office or emergency department. We observed increasing numbers of community-acquired MRSA infections in patients admitted to the hand surgery service at our suburban academic center. It is an important issue as unsuspected community-acquired MRSA hand infections can be admitted to the hospital, inadequately treated, and allowed for nosocomial spread. This study was performed to examine the trend in the incidence of community-acquired MRSA infections in patients admitted to the hand surgery service in order to sensitize practitioners to have a high index of suspicion for this entity and promote early recognition and treatment of this organism. A multihospital retrospective chart review was undertaken to compare the total number of community-acquired MRSA infections in our hospital as well as the number in patients admitted to the hand surgery service with community-acquired MRSA from 2000 through 2008. Statistical analysis was provided by linear regression. Two community-acquired hand MRSA infections were treated in 2000, as compared to three in 2001 and 2002, four in 2003, five in 2004, six in 2005, 14 in 2006, 13 in 2007, and ten in 2008. This increase was statistically significant (p = 0.038). This retrospective review documents a rapidly rising number of community-acquired MRSA hand infections in the suburban environment. The hand surgeon must be aware of the increased prevalence of this entity to adequately combat this organism and prevent prolonged hospital stays, expanded morbidity, and inflated treatment costs.