Prevalence Of Nasal Colonization Research Articles

Prevalence of nasal colonization by methicillin-resistant Staphylococcus aureus in medical students in Chile: comparison between pre-clinical and clinical environment

The primary objective of this study was to determine the prevalence of nasal colonization of methicillin resistant Staphylococcus aureus (MRSA) in medical students in pre-clinical versus clinical courses at the Pontificia Universidad Católica de Chile and to describe the epidemiological, clinical and molecular pattern of the MRSA strains obtained. A cross-sectional descriptive study was carried out on 299 undergraduate and graduate medical students from the Pontificia Universidad Católica de Chile, 44 first-year students and 29 second-year students, corresponding to students of courses without regular clinical exposure and 26 sixth-year students, 58 seventh-year and 142 residents, who are daily exposed to hospital environments. A carriage of 0% (0/73) was found in students not exposed to the clinic (pre-clinical courses) and 0.9% (2/226) in students of clinical courses, a difference that was not statistically significant (p-value 0.42). The MRSA nasal carriage found in our medical students was low, finding positive samples only in students with clinical exposure. This prevalence is similar to the one reported in other studies in Chile with similar characteristics.

Nasal Carriage of Staphylococcus aureus among staff and Students of University of Sciences and Technology, Aden-Yemen

Background: Colonization of human nose by Staphylococcus aureus represent up to 30% of the human population. S. aureus must defeats the host’s defense mechanisms in order to colonize the nasal epithelial cells of human. Some factors such as bacterial interaction in human nose can prevent such colonization.Aim: The aim of current study was to determine the prevalence of nasal colonization by S. aureus among the staff and students of University of Science & Technology, Aden; as well as the associated risk factors for nasal carriage.Subjects and Methods: The type of study was an institution-based cross-sectional study which performed during the period from January to March 2020. The total samples were 1030 nasal swabs obtained from all the staff and students, the specimens were transported to the laboratory and the swabs were processed within 4 hrs. of collection.Results: The mean age of the study sample was 21.4 (±5.8 SD). The prevalence S. aureus isolated from nasal carriages was 31%. S. aureus nasal carriage show high frequency among age group 27-36 (32.4%) followed by those at age of 17-26 years (31%), however, there was no a statistically significant association in relation to the age groups (P=0.9). Regarding gender, it was considered a risk factor. S. aureus more common in male than female. The pattern of sleep, smoking, and frequent touching the nose were statistically associated with the S. aureus nasal colonization. Those who had nasal sensitivity was considered risk factor (RR=1.3) but with non-significant association with S. aureus nasal colonization (P=0.4).Conclusion: The current study revealed that community acquired was the potential colonizers of S. aureus. With the prevalence of 31% of the study sample, age, gender, and smoking, and other were potential risks. Regular screening of carriers is required for prevention of community acquired infections.

Methicillin Resistant Staphylococcus Aureus Carrier Status among Indian Healthcare Workers: A Systematic Review and Meta-Analysis

Infection with Methicillin Resistant Staphylococcus aureus (MRSA) is a threat to quality care in the hospital.Asymptomatic colonization of MRSA escalates the burden of infection. The rate of MRSA colonizationamong healthcare workers (HCW) is not homogenous across the globe. Even though there are individualstudy reports on MRSA colonization, no pooled data is available in India. Therefore, it is important toevaluate the problem of MRSA colonization to develop a policy on preventive measures. We performeda systematic review and meta-analysis of MRSA carrier status among Indian HCWs using five databases(Scopus, PubMed-Medline, IndMed, CINAHL and Google-Scholar) from the articles published from 2008to 2017 (10 years). STATA 13.0 with metaprop package in STATA was used to find the rate of colonization.Among 2,349 HCWs, the pooled prevalence of MRSA colonization in throat, nose, axilla, palm, fingertipsand web-spaces was nine percent (CI 6% - 13%; p=0.001, I291.68%). Further, the forest plot of MRSAcolonization in nasal cavity alone was performed, and the prevalence of nasal colonization of MRSA among1,251 Indian HCWs was found to be 11% (CI 5-17%, p=0.001, I2 93.3%). The colonization rate is not veryhigh nor negligible. Therefore, the hospital administrator along with the hospital infection control committeeneeds to formulate a policy on periodic screening and decolonization of HCWs in high-risk areas.

Staphylococcus aureus Nasal Carriage and Autoimmune Diseases: From Pathogenic Mechanisms to Disease Susceptibility and Phenotype.

The role of infective agents in autoimmune diseases (ADs) development has been historically investigated, but in the last years has been strongly reconsidered due to the interest in the link between the microbiome and ADs. Together with the gut, the skin microbiome is characterized by the presence of several microorganisms, potentially influencing innate and adaptive immune response. S. aureus is one of the most important components of the skin microbiome that can colonize anterior nares without clinical manifestations. Data from the literature demonstrates a significantly higher prevalence of nasal colonization in ADs patients in comparison with healthy subjects, suggesting a possible role in terms of disease development and phenotypes. Thus, in the present narrative review we focused on the mechanisms by which S. aureus could influence the immune response and on its relationship with ADs, in particular granulomatosis with polyangiitis, rheumatoid arthritis, and systemic lupus erythematosus.

Nasal colonization with methicillin-resistant Staphylococcus aureus associated with elevated homocysteine levels in the general US adults.

Given the emergence of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) as a global health threat, understanding the risk factors for MRSA infection in the community may be a reasonable strategy to prevent it. We investigated the associations between serum homocysteine levels and prevalence of nasal colonization with S aureus and MRSA among United States adults. We conducted a cross-sectional analysis of a nationally representative sample of 7832 adults (20 years or older). The main outcome variables were nasal colonization with S aureus and MRSA. Percentages of colonization with S aureus and MRSA were calculated by the quartiles of serum homocysteine. A total of 7832 of 2051 subjects (26.2%) were culture positive for S aureus, 98 (4.8%) of whom had nasal colonization with MRSA. In comparison with subjects having the lowest serum homocysteine, the odds of nasal colonization with MRSA were significantly higher in those with the highest homocysteine (odds ratio, 3.09; 95% confidence interval, 1.11–8.61) in multivariate analysis, adjusted for all confounding variables. By contrast, homocysteine elevation was not significantly associated with S aureus colonization. Nasal colonization with MRSA in the general community was significantly associated with increases in serum homocysteine levels.

Prevalence of Nasal Colonization with Staphylococcus aureus in Patients with Rheumatoid Arthritis.

Two hundred and seven patients with RA and 37 healthy controls were prospectively included in a cross-sectional study. A nasal secretion sample was collected by swab from both anterior nostrils and was referred to the hospital's microbiology department for culturing. The mean age of the patients (168 women, 78%) was 61 ± 12 years old. The mean disease duration was 13 ± 10 years. Seventy-six percent of the patients were positive for Rheumatoid Factor (RF), and 71% were positive for Anti-citrullinated Peptides Antibodies (ACPA). Seventy percent had joint erosions. The mean DAS28 was 3.1 ± 2.2. S. aureus nasal colonization was found in 36% of the RA patients and 35% of the controls. Three patients and no controls were resistant to oxacilin/ mupirocin. The patients who were positive for ACPA had a higher prevalence of S. aureus colonization (43% vs. 17%; p < 0.05). The colonization prevalence in the patients treated with glucocorticoids was 32% (n: 133); methotrexate and/or leflunomide, 37% (n: 167); anti-TNF agents, 46% (n: 54), p < 0.05 versus patients not treated with anti-TNF agents; rituximab, 22% (n: 18); tocilizumab, 39% (n: 18). The prevalence of S. aureus nasal colonization in patients with RA does not appear to be greater than that of the general population. Anti-TNF agents might confer a higher prevalence of colonization.

Prevalence of nasal colonization of methicillin-resistant Staphylococcus aureus among schoolchildren of Barabanki district, Uttar Pradesh, India.

Introduction:The study aimed to determine the prevalence of nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA), the minimum inhibitory concentration (MIC) of oxacillin and vancomycin, inducible clindamycin resistance, and antimicrobial resistance pattern of S. aureus among children of Barabanki district, Uttar Pradesh, India.Materials and Methods:School-going children of age group of 5–15 years were identified and selected according to the inclusion and exclusion criteria. Two nasal swabs were collected from each child as per the Centers for Disease Control and Prevention guidelines and transported to laboratory. Swabs were cultured on mannitol salt agar and 5% blood agar and incubated for 18–24 h at 37°C. Identification was done as per routine laboratory protocol. Detection of MRSA was done through cefoxitin 30 μg discs and D-zone test. Antibiotic susceptibility pattern of S. aureus by Kirby–Bauer disc diffusion method along with MIC for oxacillin and vancomycin was performed simultaneously according to Clinical Laboratory Standards Institute guidelines.Results:Out of 300 children, 140 (46.67%) were found to be nasal carriage for S. aureus, among which MRSA was found to be 23 (7.67%). All S. aureus and MRSA isolates were sensitive to vancomycin with MIC <2 μg/ml, whereas 23 S. aureus were found resistant to oxacillin with MIC value >4 μg/ml. Resistance to penicillin and co-trimoxazole was highest, whereas all were sensitive to linezolid. MRSA showed 100% susceptibility to linezolid, followed by gentamicin (91.4%) and tetracycline (87%).Conclusion:With the risk involved in transmission of infection, steps for identifying the carriers and its eradication should be carried out. Rational use of antibiotics should be given preference too.

Nasal Colonization by Staphylococcus aureus in Children with Atopic Dermatitis

Background: The cutaneous and nasal microbiota, especially Staphylococcus aureus (S. aureus), plays a key role in atopic dermatitis (AD). Although this association is well known, it is difficult to establish whether colonization by these bacteria is a cause or a consequence of the disease. Objectives: The primary objectives of our study are to determine the prevalence of nasal colonization by S. aureus and its relationship with disease severity in children with AD, as well as to describe the magnitude of the association between the two. Methods: This was an analytical case-control study in children with and without AD. Participants were recruited consecutively upon presenting to the Department of Pediatric Dermatology at the General University Hospital until reaching the estimated sample size of 157 cases and 314 controls (N=471; ratio 1:2). Results: The prevalence of S. aureus nasal colonization was significantly higher in children with AD than in those without (32.5% vs. 23.9%; odds ratio (OR) 1.5, 95% CI 1.0, 2.3; p=0.047). Prevalence of colonization was not higher in the children with severe AD than in those with less severe AD. In multivariable analysis, an independent association (borderline significant) between nasal colonization by S. aureus and AD persisted after adjusting for all other study variables (OR 1.5; 95% CI 0.9, 2.6; p=0.11). Conclusions: Our paper provides further evidence of an association between atopy and nasal colonization by S. aureus, though not between nasal colonization and AD severity. The role of nasal S. aureus and the microbiota in people with AD is a controversial but crucial area of study. Greater knowledge of this topic could be clinically applicable in AD patients.

A one-year prospective study of colonization with antimicrobial-resistant organisms on admission to a Vietnamese intensive care unit.

There is a paucity of data regarding initial bacterial colonization on admission to Intensive Care Units (ICUs) in low and middle-income countries (LMICs). Patients admitted to ICUs in LMICs are at high-risk of subsequent infection with antimicrobial-resistant organisms (AROs). We conducted a prospective, observational study at the Hospital for Tropical Diseases in Ho Chi Minh City, Vietnam from November 2014 to January 2016 to assess the colonization and antimicrobial susceptibility of Staphylococcus aureus, Escherichia coli, Klebsiella spp., Pseudomonas spp. and Acinetobacter spp. among adult patients within 48 hours of ICU admission. We found the admission colonization prevalence (with at least one of the identified organisms) was 93.7% (785/838) and that of AROs was 63.1% (529/838). The colonization frequency with AROs among patients admitted from the community was comparable to those transferred from other hospitals (62.2% vs 63.8%). Staphylococcus aureus was the most commonly isolated bacteria from nasal swabs (13.1%, 110/838) and the methicillin-resistant Staphylococcus aureus nasal colonization prevalence was 8.6% (72/838). We isolated Escherichia coli from rectal swabs from almost all enrolled patients (88.3%, 740/838) and 52.1% (437/838) of patients were colonized by extended spectrum β-lactamase producing Escherichia coli. Notably, Klebsiella pneumoniae was the most frequently isolated bacteria from the tracheal swabs (11.8%, 18/153). Vietnamese ICU patients have a high rate of colonization with AROs and are thus at risk of subsequent infections with these organisms if good infection control practices are not in place.

Pneumococcal Neuraminidase A (NanA) Promotes Biofilm Formation and Synergizes with Influenza A Virus in Nasal Colonization and Middle Ear Infection.

Even in the vaccine era, Streptococcus pneumoniae (the pneumococcus) remains a leading cause of otitis media, a significant public health burden, in large part because of the high prevalence of nasal colonization with the pneumococcus in children. The primary pneumococcal neuraminidase, NanA, which is a sialidase that catalyzes the cleavage of terminal sialic acids from host glycoconjugates, is involved in both of these processes. Coinfection with influenza A virus, which also expresses a neuraminidase, exacerbates nasal colonization and disease by S. pneumoniae, in part via the synergistic contributions of the viral neuraminidase. The specific role of its pneumococcal counterpart, NanA, in this interaction, however, is less well understood. We demonstrate in a mouse model that NanA-deficient pneumococci are impaired in their ability to cause both nasal colonization and middle ear infection. Coinfection with neuraminidase-expressing influenza virus and S. pneumoniae potentiates both colonization and infection but not to wild-type levels, suggesting an intrinsic role of NanA. Using in vitro models, we show that while NanA contributes to both epithelial adherence and biofilm viability, its effect on the latter is actually independent of its sialidase activity. These data indicate that NanA contributes both enzymatically and nonenzymatically to pneumococcal pathogenesis and, as such, suggest that it is not a redundant bystander during coinfection with influenza A virus. Rather, its expression is required for the full synergism between these two pathogens.

Prevalence of Nasal Colonization by Methicillin-Resistant Staphylococcus aureus in Persons Using a Homeless Shelter in Kansas City.

Nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA) plays an important role in the epidemiology and pathogenesis of disease. Situations of close-quarter contact in groups are generally regarded as a risk factor for community-acquired MRSA strains due to transmission via fomites and person-to-person contact. With these criteria for risk, homeless individuals using shelter facilities, including showers and toilets, should be considered high risk for colonization and infection. The aim of this study was to determine the prevalence of nasal colonization of MRSA in a homeless population compared to established rates of colonization within the public and a control group of subjects from a neighboring medical school campus, and to analyze phylogenetic diversity among the MRSA strains. Nasal samples were taken from the study population of 332 adult participants and analyzed. In addition, participants were surveyed about various lifestyle factors in order to elucidate potential patterns of behavior associated with MRSA colonization. Homeless and control groups both had higher prevalence of MRSA (9.8 and 10.6%, respectively), when compared to the general population reported by previous studies (1.8%). However, the control group had a similar MRSA rate compared to health-care workers (4.6%), while the homeless population had an increased prevalence. Risk factors identified in this study included male gender, age over 50 years, and use of antibiotics within the past 3 months. Phylogenetic relationships between nine of the positive samples from the homeless population were analyzed, showing eight of the nine samples had a high degree of relatedness between the spaA genes of the MRSA strains. This indicates that the same MRSA strain might be transmitted from person-to-person among homeless population. These findings increase our understanding of key differences in MRSA characteristics within homeless populations, as well as risks for MRSA associated with being homeless, such as age and gender, which may then be a useful tool in guiding more effective prevention, treatment, and health care for homeless individuals.

Association between Staphylococcus aureus nasal carriage and disease phenotype in patients affected by systemic lupus erythematosus.

BackgroundStaphylococcus aureus (SA) is a commensal bacterium representing one of the most important components of the skin microbiome, mostly isolated in the anterior nares. A higher rate of SA nasal colonization in patients affected by Wegener’s granulomatosis and rheumatoid arthritis compared with healthy subjects (HS) has been described. No studies focusing on systemic lupus erythematosus (SLE) are available. We aimed at analyzing the prevalence of SA nasal carriers in an SLE cohort and evaluating correlation between nasal colonization and clinical, laboratory and therapeutic features.MethodsWe enrolled 84 patients with SLE (number of male/female patients 6/78; mean age 41.3 ± 12.2 years, mean disease duration 142.1 ± 103.8 months) and 154 HS blood donors. Patients with SLE underwent a physical examination and the clinical/laboratory data were collected. All the patients with SLE and the HS received a nasal swab for SA isolation and identification.ResultsSA nasal colonization prevalence was 21.4 % in patients with SLE and 28.6 % in HS (P not significant). We analyzed patients with SLE according to the presence (n = 18, SA-positive SLE) or the absence (n = 66, SA-negative SLE) of nasal colonization. Renal involvement was significantly more frequent in SA-positive SLE (11.6 % vs 3.0 %; P = 0.0009). Moreover, the presence of anti-dsDNA, anti-Sm, anti-SSA, anti-SSB, anti-RNP antibodies was significantly higher in SA-positive SLE (P < 0.0001, P = 0.01, P = 0.008, P = 0.03, P = 0.03, respectively).ConclusionSA colonization is a relatively frequent condition in patients with SLE, with a frequency similar to HS. The presence of SA seems associated with a peculiar SLE phenotype characterized by renal manifestations and autoantibody positivity, confirming the role of the microbiome in disease phenotype.

Prevalence of Nasal colonization with Staphylococcus aureus in 4 cities in Peru.

BackgroundAntimicrobial resistance (AMR) is a growing public health threat around the world and is not well characterized in the developing setting. Specifically, there is a lack of information regarding nasal colonization with S. aureus and methicillin-resistant Staphylococcus aureus (MRSA) in Latin America and Peru.MethodsThis is the report of the baseline findings of a prospective cohort study followed up over 1 year at four geographically and ecologically distinct Peruvian Air Force bases in order to determine S. aureus nasal colonization prevalence and risk factors. Additionally, all MRSA isolates underwent molecular analysis which included pulsed-field gel electrophoresis and determination of virulence and resistance genes.ResultsWe enrolled 756 military personnel. Anterior nares colonization with Staphylococcus aureus was detected in 73 of 756 participants (9.7 %) and MRSA was detected in 2 of 756 (0.3 %). Colonization rates differed significantly (P = 0.02) between geographic enrollment sites: Talara-4.3 %, Iquitos-9.1 %, Arequipa-14.0 % and Lima-11.3 %. Risk factors for S. aureus colonization included being male and a reported history of respiratory disease.ConclusionOverall, we found low prevalence of S. aureus and MRSA nasal colonization in this Peruvian military population. These findings contribute to the overall epidemiological understanding of S. aureus and MRSA in Latin America. The colonization rates which varied based on geographical location warrants further study.

Persistence of nasal colonization with human pathogenic bacteria and associated antimicrobial resistance in the German general population.

The nares represent an important bacterial reservoir for endogenous infections. This study aimed to assess the prevalence of nasal colonization by different important pathogens, the associated antimicrobial susceptibility and risk factors. We performed a prospective cohort study among 1878 nonhospitalized volunteers recruited from the general population in Germany. Participants provided nasal swabs at three time points (each separated by 4–6 months). Staphylococcus aureus, Enterobacteriaceae and important nonfermenters were cultured and subjected to susceptibility testing. Factors potentially influencing bacterial colonization patterns were assessed. The overall prevalence of S. aureus, Enterobacteriaceae and nonfermenters was 41.0, 33.4 and 3.7%, respectively. Thirteen participants (0.7%) were colonized with methicillin-resistant S. aureus. Enterobacteriaceae were mostly (>99%) susceptible against ciprofloxacin and carbapenems (100%). Extended-spectrum β-lactamase–producing isolates were not detected among Klebsiella oxytoca, Klebsiella pneumoniae and Escherichia coli. Several lifestyle- and health-related factors (e.g. household size, travel, livestock density of the residential area or occupational livestock contact, atopic dermatitis, antidepressant or anti-infective drugs) were associated with colonization by different microorganisms. This study unexpectedly demonstrated high nasal colonization rates with Enterobacteriaceae in the German general population, but rates of antibiotic resistance were low. Methicillin-resistant S. aureus carriage was rare but highly associated with occupational livestock contact.

Comparison of Methicillin Resistant Staphylococcus Aureus in Healthy Community Hospital Visitors [CA-MRSA] and Hospital Staff [HA-MRSA

BackgroundThe prevalence of community-associated methicillin-resistant Staphylococcus aureus [CA-MRSA] is unknown in Oman.MethodsNasal and cell phones swabs were collected from hospital visitors and health-care workers on sterile polyester swabs and directly inoculated onto a mannitol salt agar containing oxacillin, allowing growth of methicillin-resistant microorganisms. Antibiotic susceptibility tests were performed using Kirby Bauer’s disc diffusion method on the isolates. Minimum inhibitory concentration (MIC) was determined for vancomycin and teicoplanin against the resistant isolates of MRSA by the Epsilometer [E] test. A brief survey questionnaire was requested be filled to ascertain the exposure to known risk factors for CA-MRSA carriage.ResultsOverall, nasal colonization with CA-MRSA was seen in 34 individuals (18%, 95% confidence interval [CI] =12.5%–23.5%), whereas, CA-MRSA was additionally isolated from the cell phone surface in 12 participants (6.3%, 95% CI =5.6%–6.98%). Nasal colonization prevalence with hospital-acquired [HA] MRSA was seen in 16 individuals (13.8%, 95% confidence interval [CI] =7.5%–20.06%), whereas, HA-MRSA was additionally isolated from the cell phone surface in 3 participants (2.6%, 95% CI =1.7–4.54). Antibiotic sensitivity was 100% to linezolid and rifampicin in the CA-MRSA isolates. Antibiotic resistance to vancomycin and clindamycin varied between 9–11 % in the CA-MRSA isolates. Mean MIC for vancomycin amongst CA- and HA-MRSA were 6.3 and 9.3 μg/ml, whereas for teicoplanin they were 13 and 14 μg/ml respectively by the E-test. There was no statistically significant correlation between CA-MRSA nasal carriage and the risk factors (P>0.05, Chi-square test).ConclusionsThe prevalence of CA-MRSA in the healthy community hospital visitors was 18 % (95% CI, 12.5% to 23.5%) as compared to 13.8% HA-MRSA in the hospital health-care staff. Despite a significant prevalence of CA-MRSA, these strains were mostly sensitive. Recommendation: The universal techniques of hand washing, personal hygiene and sanitation are thus warranted.

Molecular epidemiology of methicillin resistant staphylococcus aureus colonizing the anterior Nares of school children of Udupi Taluk

Context: Community associated methicillin resistant Staphylococcus aureus (CA-MRSA) cause serious skin and soft tissue infections including necrotizing fasciitis and necrotizing pneumonia. Production of Panton Valentine Leucocidine (PVL) toxin is implicated in its enhanced virulence. A variant of epidemic MRSA-15 (EMRSA-15) which produces PVL toxin has been isolated and characterized by pulsed-field gel electrophoresis (PFGE) method from the Indian population both in hospital and community settings. Aims: Identify the epidemiological type of MRSA colonizing the anterior nares of school children in Udupi taluk. Settings and Design: The study population included children of the age group of 5-16 years belonging to the Udupi taluk of Karnataka, India. A total of 1503 children were screened for MRSA colonization during July 2009 to December 2010. Materials and Methods: PVL assay, Staphylococcal Cassette Chromosome (SCC) mec typing and PFGE typing were carried out with all the MRSA isolates. Statistical Analysis Used: Frequency distribution of different variables was assessed by SPSS. Results: Among the 1.1% of MRSA, 58.8% (10/17) of isolates were positive for pvl and 41.7% (7/17) were identified as SCC mec type IV. PFGE patterns of all the strains were identical with Indian variant EMRSA-15; however they were different from classical EMRSA-15 in 3-4 bands. Conclusions: The Indian variant EMRSA-15 gains much epidemiological relevance owing to the acquisition of pvl gene. In spite of low prevalence of nasal colonization of MRSA, emergence of the virulent Indian variant EMRSA-15 in our community is a worrisome fact to be reckoned with.

Molecular analysis and susceptibility pattern of meticillin-resistant Staphylococcus aureus strains in emergency department patients and related risk factors in Iran

Meticillin-resistant Staphylococcus aureus (MRSA) has become widespread in the hospital and in the community. Nasal colonization with MRSA has been identified as a risk factor for MRSA infection. To determine the prevalence of nasal colonization with MRSA among adult patients in the emergency department (ED) by considering the risk factors for MRSA carriage and antibiotic susceptibility patterns. A cross-sectional study was conducted among 810 patients in the ED in Kashan, Iran. A questionnaire concerning the risk factors for MRSA colonization was completed for each patient. Specimens were obtained from the anterior nares. A multiplex polymerase chain reaction (PCR) assay was used for SCCmec typing, and a PCR assay was used to detect Panton-Valentine leukocidin (PVL) genes. MRSA susceptibility to amikacin, clindamycin, gentamicin, ciprofloxacin, penicillin, trimethoprim/sulfamethoxazole, erythromycin, tetracycline, vancomycin and cefoxitin was determined by the disc diffusion method. Two hundred and ninety-six (36.5%) and 26 (3.2%) out of 810 patients were S. aureus and MRSA nasal carriers, respectively. Of these, nine (34.6%), seven (26.9%), two (7.7%), two (7.7%), two (7.7%), one (3.8%) and one (3.8%) MRSA isolates were classified as type V, III, I, IVb, IVh, II and IVa, respectively, and seven (26.9%) MRSA isolates were non-typeable. PVL genes were not detected. All MRSA isolates were multi-drug resistant. A significant association was found between previous hospitalization, use of urinary and/or venous catheters and MRSA colonization. Further work on the epidemiology and risk factors for MRSA nasal colonization may be useful to guide the treatment and prevention of MRSA infections.

AB0512 Nasal Carriage of Staphylococcus Aureus in Patients with Systemic Lupus Erythematosus: Cause or Effect?

BackgroundStaphylococcus aureus (SA) is a commensal bacterium which can be isolated mostly in the anterior nares. In immunosuppressive patients, SA could cause various infections, ranging from minor skin infections to...

Methicillin-resistant Staphylococcus aureus nasal colonization in a department of pediatrics: a cross-sectional study

BackgroundWe describe methicillin-resistant Staphylococcus aureus (MRSA) nasal carriage at admission in patients admitted to a Department of Pediatrics.MethodsAll patients received a nasal swab at admission. A questionnaire was administered and molecular genetics analyses were performed on all identified MRSA isolates.ResultsWe enrolled 785 patients, affected with both acute and chronic diseases. MRSA nasal colonization prevalence was 1.15% (CI: 0.5607%-2.093%). Methicillin-sensitive Staphylococcus aureus (MSSA) nasal colonization prevalence at admission was 19.75% (CI 17.07%-22.64%). Only one MRSA isolate carried the SCCmec V variant; all other isolates carried the SCCmecIV variant. Five out of 9 MRSA-colonized patients had an underlying condition. Antibiotic therapy in the previous 6 months was a protective factor for both MRSA (OR 0,66; 95% CI: 0,46-0,96) and MSSA (OR 0,65; 95% CI: 0,45-0,97) colonization. A tendency to statistical significance was seen in the association between hospitalization in the 6 months prior to admission and MRSA colonization at admission (OR 4,92; 95% CI: 0,97-24,83). No patient was diagnosed with an S. aureus infection during hospitalization.ConclusionsThe majority of our MRSA colonizing isolates have community origins. Nevertheless, most MRSA-colonized patients had been hospitalized previously, suggesting that strains that circulate in the community also circulate in hospital settings. Further studies should elucidate the role of children with frequent contact with health care institutions in the circulation of antibiotic resistant strains between the hospital and the community.

Nasal colonization with Staphylococcus aureus in individuals with HIV/ AIDS attended in a Brazilian Teaching Hospital

to evaluate the prevalence of nasal colonization with Staphylococcus aureus in individuals with HIV/AIDS under inpatient treatment in a teaching hospital in the state of São Paulo (Brazil). a cross-sectional study undertaken in two units specialized in attending people living with HIV/AIDS, in the period August 2011 - July 2012. Socio-demographic and clinical data was collected through individual interviews and from the medical records; samples of nasal secretion were collected with Stuart swabs on the first day of inpatient treatment. Ethical aspects were respected. of the 229 individuals with HIV/AIDS hospitalized in this period, 169 participated in the study, with Staphylococcus aureus being identified in the culture tests of 46 (27.2%) of the individuals, resistance to oxacillin being evidenced in 10 (21.8%) participants. the results of the research indicate that the prevalence of colonization with Staphylococcus aureus in individuals with HIV/AIDS in the specialized units was considered relevant, possibly contributing to future investigations and, moreover, to the implementation of measures to prevent and control this pathogen in this population.