Screening and decolonization of MRSA among joint arthroplasty patients: efficacy, cost-effectiveness and durability

Application of 233 nm far-UVC LEDs for eradication of MRSA and MSSA and risk assessment on skin models

A newly developed UVC LED source with an emission wavelength of 233 nm was proved on bactericidal efficacy and skin tolerability. The bactericidal efficacy was qualitatively analysed using blood agar test. Subsequently, quantitative analyses were performed on germ carrier tests using the MRSA strain DSM11822, the MSSA strain DSM799, S. epidermidis DSM1798 with various soil loads. Additionally, the compatibility of the germicidal radiation doses on excised human skin and reconstructed human epidermis was proved. Cell viability, DNA damage and production of radicals were assessed in comparison to typical UVC radiation from discharge lamps (222 nm, 254 nm) and UVB (280–380 nm) radiation for clinical assessment. At a dose of 40 mJ/cm², the 233 nm light source reduced the viable microorganisms by a log₁₀ reduction (LR) of 5 log₁₀ levels if no soil load was present. Mucin and protein containing soil loads diminished the effect to an LR of 1.5–3.3. A salt solution representing artificial sweat (pH 8.4) had only minor effects on the reduction. The viability of the skin models was not reduced and the DNA damage was far below the damage evoked by 0.1 UVB minimal erythema dose, which can be regarded as safe. Furthermore, the induced damage vanished after 24 h. Irradiation on four consecutive days also did not evoke DNA damage. The radical formation was far lower than 20 min outdoor visible light would cause, which is classified as low radical load and can be compensated by the antioxidant defence system.

Prevalence of Staphylococcus aureus colonization in patients for total joint arthroplasty in South Africa

BACKGROUND

Periprosthetic joint infections (PJIs) are a major source of morbidity and mortality for patients undergoing total joint arthroplasty (TJA). Staphylococcus aureus (S. aureus) colonization is an independent, modifiable risk factor for periprosthetic joint infections. Post-operative infections are reported to be ten times greater in S. aureus carriers than in non-carriers in developed countries though recorded data is lacking for the developing world. This study aims to determine the prevalence of S. aureus colonization in patients awaiting TJA in South Africa.

METHODS

We prospectively assessed 119 patients awaiting total knee arthroplasty and total hip arthroplasty between May and October 2016. We screened three separate anatomical sites on each patient for S. aureus. Patients with positive cultures were treated with intranasal mupirocin ointment and chlorhexidine body wash. Univariate and comparative statistical analyses to determine risk factors for colonization was conducted using t tests, Fisher's exact tests, and chi-square analyses.

RESULTS

The overall prevalence of methicillin-sensitive S. aureus colonization was 31.9% (n = 38). There were no patients colonized with methicillin-resistant S. aureus. Nasal swabs returned a yield of 81.6% (n = 31), with groin swabs and axillary swabs at 39.5% (n = 15) and 28.9% (n = 11), respectively. Eradication was successful in 94.74% (n = 36) after 5 days treatment. All patients (100%) were decolonized after counseling and repeat eradication treatment. The overall complication rate was 7.6% (n = 9). The 30-day readmission rate in the S. aureus-colonized group was 7.9% (n = 3) as opposed to 7.4% (n = 6) in the non-colonized cohort. There were no 60- and 90-day readmissions and no cases were revised at a mean follow-up of 2.26 years.

CONCLUSIONS

The rate of S. aureus colonization in patients undergoing elective TJA in a developing country was 31.9% and is equivalent to reported rates in developed countries. Eradication treatment with combined intranasal mupirocin ointment and chlorhexidine body wash is a successful treatment modality. A larger cohort of patients is recommended to determine risk factors and post-operative septic sequelae in this population group.

[Spectrum of pathogens in postoperative complications of visceral surgery : The problem of multidrug resistance]

In general surgery the etiology of surgical site infections has not significantly changed over the last 30 years. Gram-positive bacteria, e.g. coagulase negative staphylococci (CNS), Staphylococcus aureus and Enterococcus spp. as well as Gram-negative bacteria, e.g. Escherichia coli, Enterobacter spp., Klebsiella spp. and Pseudomonas aeruginosa, are the most common findings. Although in general surgery 10% of the S. aureus causing postoperative wound infections were methicillin resistant (MRSA), no cases of multidrug-resistant Gram-negative (MRGN) bacteria were reported. Yeasts (particularly Candida spp.) are rarely the pathogen causing surgical site infections (≤3%) and concomitant risk factors are typical (e.g. diabetes, chemotherapy, immunosuppression and malnutrition). Viruses are rarely the cause of surgical site infections. Transmission can occur by HBV, HCV or HIV positive surgical staff or in organ transplantations and postoperative reactivation of persistent infections is possible (especially for HBV, HCV, CMV, EBV and HIV). The principles for prevention of surgical site infections are dealt with as consequences of preoperative colonization by MRSA, methicillin-sensitive S. aureus (MSSA) and MRGN and reviewed with respect to screening, perioperative antibiotic prophylaxis and decolonization. In nosocomial peritonitis, the selection of antibiotics should consider previous antibiotic treatment. A single intra-abdominal detection of Candida spp. usually does not require antimycotic treatment in postoperatively stable and immunocompetent patients but is recommended in severe community-acquired or nosocomial peritonitis. Viral infections can be avoided by screening of organ donors and serological surveillance of surgery personnel.

Systematic review of a patient care bundle in reducing staphylococcal infections in cardiac and orthopaedic surgery

Surgical site infections (SSIs) are serious adverse events hindering surgical patients' recovery. In Australia and New Zealand, SSIs are a huge burden to patients and healthcare systems. A bundled approach, including pre-theatre nasal and/or skin decolonization has been used to reduce the risk of staphylococcal infection. The aim of this review is to assess the effectiveness of the bundle in preventing SSIs for cardiac and orthopaedic surgeries. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Published literature was searched in PubMed, Embase and Cochrane Library of Systematic reviews. Identified articles were selected and extracted based on a priori defined Population-Intervention-Comparator-Outcome and eligibility criteria. Data of randomized controlled trials (RCTs) and comparative observational studies were synthesized by meta-analyses. Quality appraisal tools were used to assess the evidence quality. The review included six RCTs and 19 observational studies. The bundled treatment regimens varied substantially across all studies. RCTs showed a trend of Staphylococcus aureus SSIs reduction due to the bundle (relative risk = 0.59, 95% confidence interval (CI) = 0.33, 1.06) with moderate heterogeneity. Observational studies showed statistically significant reduction in all-cause and S. aureus SSIs, with 51% (95% CI = 0.41, 0.59) and 47% (95% CI = 0.35, 0.65), respectively. No publication biases were detected. SSIs in major cardiac and orthopaedic surgeries can be effectively reduced by approximately 50% with a pre-theatre patient care bundle approach.

Colonization With Methicillin-resistant Staphylococcus aureus and Risk for Infection Among Asymptomatic Athletes: A Systematic Review and Metaanalysis

BACKGROUND

Athletes are a vulnerable population for methicillin-resistant Staphylococcus aureus (MRSA) infection. Our aim was to determine MRSA colonization in asymptomatic athletes and estimate the risk for subsequent MRSA infection.

METHODS

We searched the PubMed and EMBASE (through 29 October 2015) for studies on MRSA colonization among asymptomatic athletes.

RESULTS

The pooled prevalence of MRSA colonization among athletes was 6% (95% confidence interval [CI], 1,13), and it was higher in the United States (8%; 95% CI, 2,17). USA300 was the most common strain detected (22%), and 62% and 36% of isolates were resistant to clindamycin and trimethoprim/sulfamethoxazole, respectively. The prevalence of MRSA colonization among collegiate athletes reached 13% (95% CI, 4,25). Sports with the highest prevalence among collegiate athletes were wrestling (22%; 95% CI, 0,85), football (8%; 95% CI, 3,15) and basketball (8%; 95% CI, 0,28). The risk for MRSA skin and soft tissue infection within 3 months after documented colonization among MRSA-colonized athletes was significantly higher than for noncolonized athletes (relative risk = 7.37, 95% CI, [2.47,21.94]). Decolonization treatment among colonized athletes decreased significantly the risk for infection (relative risk reduction = 0.33; 95% CI, .03,4.28).

CONCLUSIONS

The prevalence of MRSA colonization among asymptomatic athletes is comparable to that among individuals with chronic illness, it is higher among collegiate athletes and can be twice that for patients in intensive care units. Importantly, colonization is associated with a >7-fold increase in the incidence of subsequent MRSA infection. Infection control and decontamination protocols for this population need to be studied and implemented with urgency.