Risk Factors For Nasal Colonization Research Articles

Identification of Risk Factors for Nasal Colonization of Methicillin-resistant Staphylococcus aureus and Vancomycin-resistant Staphylococcus aureus in Health Workers at a Tertiary Hospital, Indonesia

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin-resistant S. aureus (VRSA) frequently cause nosocomial infections yearly. During the COVID-19 pandemic, the potential for excessive use of antibiotics is a global threat to the increasing incidence of multiresistant bacteria. AIM: This study aimed to determine MRSA and VRSA colonization and identify factors associated with the risk of MRSA and VRSA nasal colonization in health workers at Dr. Soemarno Sosroatmodjo General Hospital, Kuala Kapuas, as one of the type C hospitals in Indonesia. METHODS: This cross-sectional analytic study at Dr. Soemarno Sosroatmodjo General Hospital, a tertiary hospital in Indonesia. A 128 health workers’ subjects had undergone nasal swab screening for MRSA and VRSA colonization examinations. Then, they were asked to complete a questionnaire concerning the risk factors of MRSA and VRSA infections. RESULTS: Nasal swab results obtained as many as 30 (23.5%) MRSA positive subjects and 6 (4.7%) subjects with positive VRSA. The most common risk factors that led to MRSA colonization included a history of positive MRSA in the previous hospital (60%), a history of ear, nose, and throat infection (41.7%), and did not do hand rub/handwash (36.7%). In comparison, the most risk factors for VRSA colonization were having pigs farm at home (33.3%), a history of positive MRSA in the previous hospital (20%), and a history of hospitalization in the past 6–12 months (16.7%). The results of multivariate analysis showed the most powerful and statistically significant risk factors in influencing nasal MRSA colonization were a history of positive MRSA in the previous hospital (OR 13.69, 95% confidence intervals [CI]: 1.34–140.25, p = 0.028) and did not do hand rub/handwash (OR 2.95, 95% CI: 1.167–7.49, p = 0.023). Meanwhile, marital status (OR 0.160, 95% CI: 0.02–1.06), p = 0.058) and home care service (OR 6.10, 95% CI: 0.79–46.96, p = 0.082) were the strongest risk factors for nasal colonization of VRSA but not statistically significant. CONCLUSION: As many as, 23.5% and 4.7% of healthcare workers’ subjects were found with nasal colonization of MRSA and VRSA, respectively. Accordingly, strict policies are needed to minimize the transmission of these organisms from the hospital setting to the community.

P18 Prevalence and risk factors for nasal colonization with MRSA among children attending immunization in Port Harcourt, Nigeria

Background Staphylococcus aureus is a bacterial agent commonly found on the skin and anterior nares of healthy individuals. There has been an increase in the carriage of MRSA globally. Nasal MRSA colonization is a public health problem because it is a significant risk factor for staphylococcal infection. This study explores the prevalence, antibiotic susceptibility profile and risk factors for nasal colonization of healthy children under 5 years old attending immunization.MethodsNasal swabs were collected from 176 healthy children 0–60 months old, attending routine immunization in Port Harcourt. Questionnaires covering demographic information and potential risk factors were administered to caregivers of the children. Collected samples were tested for the presence of MSSA and MRSA. Antibiotic susceptibility testing was carried out on all MSSA and MRSA samples.ResultsThe prevalence of MSSA and MRSA were 10/176 (5.68%) and 48/176 (27.3%), respectively. The MDR rate among the 58 S. aureus samples was 53/58 (91.38%). Children who had an ear infection in the preceding 1 month were at a higher risk of being colonized with MRSA at P = 0.048 (95% CI). There was also a significant association P = 0.036 (95% CI) between the educational status of mother and nasal colonization, with higher educational status reducing the chances of association.ConclusionsThere is a rising prevalence of MRSA colonization and MDR strains. A history of ear infections and a poor level of education of the mother were identified as significant risk factors for MRSA colonization.Table 1.Association between potential risk factors and MRSA carriageFactorsMRSAχ2 P valuepositivenegativeHospitalization0.3770.539f Yes01 No48127Hospital visit0.1400.708 Yes511 No43117RTI0.8630.353 Yes2474 No2454Ear infection4.8600.048* f Yes42 No44126Antibiotic use1.3750.241 Yes935 No3993Family health worker0.3040.582 Yes510 No43118Smoker1.6380.243f Yes213 No46114*Significant at 95%; fFisher's exact test.

Risk Factors Association for MRSA Nasal Colonization in Preoperative Patients in Azadi Teaching Hospital-Duhok, Kurdistan Region, Iraq

Background: Nasal colonization with Methicillin-resistant Staphylococcus aureus (MRSA) can predispose to subsequent infections in surgical and non-surgical patients, making the management challenging with increased rates of morbidity, mortality and cost burden.
 Objectives: The present study was carried out to evaluate the risk factors of MRSA nasal colonization in preoperative patients in Azadi Teaching Hospital in Duhok Province - Kurdistan Region-Iraq.
 Methods: Nasal swabs were obtained from 150 patients after completing a questionnaire. Conventional laboratory methods were carried out to identify Staphylococcus aureus (S. aureus) and antimicrobial susceptibility test was conducted for recognizing MRSA isolates.
 Results: A total of 41 (27.3%) of 150 patients were MRSA carriers. The mean age of participants MRSA carriers was 35.27±20.40 years old. The highest prevalence rate of nasal colonization with MRSA was in males (27.94%) than females (26.82%). In logistic regression analysis, no significant differences was detected between MRSA carriage and the associated risk factors including age [OR: 0.99 (95 % CI: 0.97- 1.01); P = 0.45], gender [OR: 1.05 (95 % CI: 0.51- 2.17); P = 0.87] and medical comorbidities [OR: 1.11 (95 % CI: 0.42- 2.92); P = 0.82].
 Conclusions: Age, gender and medical comorbidities were not associated common risk factors for nasal colonization of MRSA in preoperative patients. This study should be considered preliminary and studies with larger sample sizes and with using advance molecular tools are needed in the future.

Colonization of HIV-Infected Children with Methicillin-Resistant Staphylococcus aureus.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) poses a public health threat owing to its extensive resistance to antibiotics, association with persistent outbreaks, and markedly increased healthcare costs. Moreover, HIV-infected individuals are at a greater risk for colonization with MRSA, and may act as reservoirs for subsequent transmission to other individuals. In Ghana, little is known about MRSA in relation to at-risk populations, such as HIV-infected children. The aim of this study was to investigate nasal carriage of S. aureus and MRSA among HIV-infected children in Accra, including the prevalence, risk factors and antibiotic resistance. Methodology: The study was cross-sectional, and involved 107 children with HIV infection and an equal number of sex- and age group- matched apparently healthy controls recruited from the Princess Marie Louis Children’s Hospital in Accra. Nasal swab specimens were collected from the study participants and cultured for bacteria. S. aureus isolates were confirmed by the coagulase test while MRSA was confirmed by PCR of the mecA gene. Antimicrobial susceptibility testing of S. aureus isolates was done by the Kirby Bauer method. A structured questionnaire was used to collect data on demographic, household and clinical features of the study participants. A logistic regression analysis was performed to identify determinants of S. aureus and MRSA carriage among participants of both study groups. Results: The carriage prevalence of S. aureus and MRSA were 44.9% (48) and 5.6% (6), respectively, among the HIV-infected individuals, and the corresponding values within the control group were 23.4% (25) and 0.9% (1). There was a significant association between HIV infection and S. aureus colonization (p < 0.001), but not MRSA colonization (p = 0.055). The main predictor of S. aureus colonization in both study groups was absence of colonization with coagulase negative staphylococcus (p < 0.001). Furthermore, the main predictor of MRSA colonization was regular hand washing with soap (p = 0.043); this was observed among HIV-infected individuals but not the control group. The proportion of S. aureus isolates that were multidrug resistant was 62.3% (33/53) in the HIV-infected group and 80% (20/25) in the control group (p = 0.192). Conclusions: HIV infection is a risk factor for nasal colonization of S. aureus among children in Accra but may not be for MRSA. Both the HIV-infected and uninfected children are reservoirs of multidrug resistant S. aureus. Demographic, household and clinical features appear to have little or no relationship with S. aureus and MRSA colonization in the study children.

School environmental contamination of methicillin-sensitive Staphylococcus aureus as an independent risk factor for nasal colonization in schoolchildren: An observational, cross-sectional study.

ObjectiveWe aim to assess the similarities of proportional, phenotypic, and molecular characteristics between the school environment and schoolchildren on methicillin-sensitive S. aureus (MSSA) isolates.MethodsA cross-sectional study was conducted between March 2016 and August 2016 in eight elementary schools in Guangzhou, China. Nasal swabs from students and environmental swabs from school environments were collected. Univariate and multivariate logistic regression analyses under a multistage stratified cluster cross-sectional survey design were performed to access the prevalence relationship and influencing factors, respectively. Phenotypic and molecular characterizations of MSSA isolates were conducted using the Kirby-Bauer disk diffusion method and polymerase chain reaction assays, respectively.ResultsIn total, 1705 schoolchildren and 1240 environmental samples from 40 classes in eight elementary schools obtained between March and August 2016 were include in this study. The rates of MSSA prevalence among schoolchildren and the environment were 11.44% (195/1705) and 4.60% (57/1240), respectively. The odds ratios and 95% confidence intervals (CIs) on the prevalence of MSSA isolates were 1.11 (95% CI, 1.05–1.29; P = 0.010) and 1.04 (95% CI, 1.01–1.07; P = 0.003) for the school or class environment and students, respectively. Similar phenotypic and molecular characteristics were identified between schoolchildren and the environment. A cause and effect relationship could not be established because the study design was cross-sectional.ConclusionsBecause of the cross-sectional design, we can reveal the association between school environment and schoolchildren on MSSA, but it is not a cause and effect relationship.

A community-based study on nasal carriage of Staphylococcus aureus among healthy schoolchildren and its antimicrobial susceptibility pattern

BACKGROUND: Invasive infections from Staphylococcus aureus are increasingly being encountered in healthy children. Nasal colonization of S. aureus is associated with increased risk for acquiring invasive disease. The objective of this study was to determine the prevalence and risk factors for S. aureus nasal colonization among a healthy pediatric population and to determine antibiotic susceptibilities of the S. aureus isolates. MATERIALS AND METHODS: Using a cross-sectional study design, a total of 468 children of age group 5–16 years from 15 different schools of urban Belgaum (Belagavi) located under Ramnagar Urban Health Centre of KLE University's Jawaharlal Nehru Medical College, India, were screened for S. aureus colonization. Information on selected risk factors for nasal colonization of S. aureus was obtained through a questionnaire. Samples were obtained from the anterior nares and processed. S. aureus isolates were confirmed by growth on selective media and coagulase testing. Disc diffusion antibiotic susceptibility tests were performed according to the Clinical and Laboratory Standard Institute guidelines. RESULTS: Of the 468 children included in the study, S. aureus was isolated from the anterior nares in 142 (30.3%) children. S. aureus isolates exhibited resistance to multiple classes of antibiotics including co-trimoxazole resistance (19.7%), ciprofloxacin (47.9%), erythromycin resistance (33.1%), clindamycin resistance (4.9%), amoxiclav (1.4%), and linezolid (4.9%). CONCLUSION: Children in India have a high rate of nasal colonization of S. aureus. The high rate of resistance to many classes of antibiotics among S. aureus strains is of great concern warranting continued surveillance and antimicrobial stewardship.

Risk Factors for Staphylococcus aureus Nasal Colonization in Joint Arthroplasty Patients

BackgroundSeveral studies have shown that Staphylococcus aureus (S aureus) nasal colonization is associated with surgical site infection and that preoperative decolonization can reduce infection rates. Up to 30% of joint arthroplasty patients have positive S aureus nasal swabs. Patient risk factors for colonization remain largely unknown. The aim of this study was to determine whether there is a specific patient population at increased risk of S aureus nasal colonization. MethodsThis study is a retrospective review of 716 patients undergoing hip or knee arthroplasty beginning in 2011. All patients were screened preoperatively for nasal colonization. Univariate and multivariate analyses were used to assess risk factors for nasal colonization. ResultsA total of 716 patients undergoing joint arthroplasty had preoperative nasal screening. One hundred twenty-five (17.50%) nasal swabs were positive for methicillin-susceptible S aureus (MSSA), 13 (1.80%) were positive for methicillin-resistant S aureus (MRSA), and 84 (11.70%) were positive for other organisms. In bivariate analysis, diabetes (P = .04), renal insufficiency (P = .03), and immunosuppression (P = .02) were predictors of nasal colonization with MSSA/MRSA. In multivariate analysis, immunosuppression (P = .04; odds ratio, 2.0; 95% confidence interval, 1.03-3.71) and renal insufficiency (P = .04; odds ratio, 2.5; 95% confidence interval, 1.01-6.18) were independent predictors of nasal colonization with MSSA/MRSA. ConclusionOverall, 17.5% of patients undergoing primary hip or knee arthroplasty screened positive for S aureus. Diabetes, renal insufficiency, and immunosuppression are risk factors for such colonization. Given that these comorbidities are already known independent risk factors for periprosthetic joint infection, these patients should be particularly screened and when necessary, decolonized.

Risk Factors for Nasal Colonization by Methicillin-Resistant Staphylococci in Healthy Humans in Professional Daily Contact with Companion Animals in Portugal.

Methicillin-resistant staphylococci (MRS), namely Staphylococcus aureus (MRSA) and Staphylococcus pseudintermedius (MRSP), are opportunistic agents of great importance in human and veterinary medicine. The aims of this study were to investigate the frequency, persistence, and risk factors associated with nasal colonization by MRS in people in daily contact with animals in Portugal. Seventy-nine out of 129 (61.2%) participants were found to be colonized by, at least, one methicillin-resistant (MR) staphylococci species (MR Staphylococcus epidermidis [n = 68], MRSA [n = 19], MR Staphylococcus haemolyticus [n = 7], MRSP [n = 2], and other coagulase-negative staphylococci [n = 4]). Three lineages were identified among the MRSA isolates (n = 7): the major human healthcare clone in Portugal (ST22-t032-IV, n = 3), the livestock-associated MRSA (ST398-t108-V, n = 3), and the New York-/Japan-related clone (ST105-t002-II, n = 1). MRSP isolates belonged to the European clone ST71-II-III. We identified two risk factors for nasal colonization by MRS in healthy humans: (i) being a veterinary professional (veterinarian and veterinary nurse) (p < 0.0001, odds ratio [OR] = 6.369, 95% confidence interval [CI, 2.683-15.122]) and (ii) have contacted with one MRSA- or MRSP-positive animal (p = 0.0361, OR = 2.742, 95% CI [1.067-7.045]). The follow-up study revealed that the majority (85%) remain colonized. This study shows that MRS in veterinary clinical practice is a professional hazard and highlights the need to implement preventive measures to minimize spread.

Skin and soft tissue infections in intercontinental travellers and the import of multi-resistant Staphylococcus aureus to Europe

Staphylococcus aureus is emerging globally. Treatment of infections is complicated by increasing antibiotic resistance. We collected clinical data and swabs of returnees with skin and soft tissue infections (SSTI) at 13 travel-clinics in Europe (www.staphtrav.eu). Sixty-two percent (196/318) SSTI patients had S. aureus-positive lesions, of which almost two-thirds (122/196) were Panton–Valentine leukocidin (PVL) positive. PVL was associated with disease severity, including hospitalization for SSTI (OR 5.2, 95% CI 1.5–18.2). In returnees with SSTI, longer travel and more intense population contact were risk factors for nasal colonization with PVL-positive S. aureus. Imported S. aureus frequently proved resistant to trimethoprim-sulfamethoxazole (21%), erythromycin (21%), tetracycline (20%), ciprofloxacin (13%), methicillin (12%) and clindamycin (8%). Place of exposure was significantly (p < 0.05) associated with predominant resistance phenotypes and spa genotypes: Latin America (methicillin; t008/CC24/304), Africa (tetracycline, trimethoprim-sulfamethoxazole; t084/CC84, t314/singleton, t355/CC355), South Asia (trimethoprim-sulfamethoxazole, ciprofloxacin; t021/CC21/318), South-East Asia (clindamycin; t159/CC272). USA300-like isolates accounted for 30% of all methicillin-resistant S. aureus imported to Europe and were predominantly (71%) acquired in Latin America. Multi-resistance to non-β-lactams were present in 24% of imports and associated with travel to South Asia (ORcrude 5.3, 95% CI 2.4–11.8), even after adjusting for confounding by genotype (ORadjusted 3.8, 95% 1.5–9.5). Choosing randomly from compounds recommended for the empiric treatment of severe S. aureus SSTI, 15% of cases would have received ineffective antimicrobial therapy. These findings call for the development of regionally stratified guidance on the antibiotic management of severe imported S. aureus disease and put the infected and colonized traveller at the centre of interventions against the global spread of multi-resistant S. aureus.

Risk Factors for Methicillin Resistant Staphylococcus aureus Nasal Colonization of Healthy Children.

Background:Nasal colonization of healthy children with Staphylococcus aureus is an important risk factor for different infections. Detection of colonized individuals with methicillin resistant S. aureus (MRSA) and its eradication is the proper prevention strategy for infection spread in the community and health-care centers.Objectives:The aim of this study was to determine the prevalence, associated risk factors and antibiotic resistance pattern among healthy children who were nasal carriers of S. aureus.Patients and Methods:This cross-sectional study was conducted on 350 one month to 14-year-old healthy children living in Kashan/Iran. The nasal specimens were cultured in blood agar medium for S. aureus. Positive cultures were evaluated for cephalothin, co-trimoxazole, clindamycin, ciprofloxacin, oxacillin and vancomycin susceptibility by the disc diffusion method and E-test. Risk factors for nasal carriage of S. aureus and MRSA were evaluated.Results:Frequency of S. aureus nasal carriage was 92 from 350 cases (26.2%), amongst which 33 (35.9%) were MRSA. Isolates indicated an overall resistance of 52.2% to cephalothin, 33.7% to co-trimoxazol, 26.1% to ciprofloxacin, 26.1% to clindamycin, 35.9% to oxacillin and 4.3% to vancomycin. Factors associated with MRSA nasal carriage included gender (P value 0.001), age of less than four years (P value 0.016), number of individuals in the family (P value < 0.001), antibiotic use (P value < 0.001) and admission (P value < 0.001) during the previous three months, parental smoking (P value < 0.001) and sleeping with parents (P value 0.022).Conclusions:Age of less than four years, male sex, family size being more than four, antibiotic use and admission during the previous three months, parental smoking and sleeping with parents were independent risk factors for nasal colonization with MRSA.

Prevalence of Community-Acquired Methicillin-Resistant Staphylococcus aureus Nasal Colonization Among Children.

Invasive infections from community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are increasingly being encountered in healthy children. Nasal colonization of MRSA is associated with increased risk for acquiring invasive disease. The objective of this study was to determine prevalence and risk factors for CA-MRSA nasal colonization among a healthy paediatric population and to determine antibiotic susceptibilities of S. aureus isolates. Using a cross-sectional study design, children aged 1mnth-17y attending well-child clinic at an academic hospital and a local public school in Mangalore, India were screened for S. aureus colonization via nasal swabs. A questionnaire was administered and data on risk factors for nasal colonization was collected. Samples were obtained from the anterior nares and cultured quantitatively. S. aureus isolates were confirmed by growth on selective media and coagulase testing. Disk diffusion antibiotic susceptibility tests were performed according to Clinical and Laboratory Standard Institute guidelines. Of the 500 children included in the study, S. aureus was isolated from the anterior nares in 126 (25%) children; four (3%) isolates were classified as CA-MRSA. Factors associated with S. aureus nasal colonization were children <6 y old (p=0.030) and members of joint families (p=0.044). Resistance to many classes of antibiotics were noted among S. aureus isolates including trimethoprim-sulfamethoxazole (39%), ciprofloxacin (16%), erythromycin (19%) and clindamycin (5%). Inducible clindamycin resistance (positive D test) was detected in 11 of the erythromycin-resistant strains not already classified as resistant to clindamycin. No resistance to vancomycin was observed. Children in India have a high rate of nasal colonization of S. aureus. Nasal colonization of community-associated methicillin-resistant S. aureus exists but is still low among healthy children. The high rate of resistance to many classes of antibiotics among S. aureus strains is of great concern warranting continued surveillance and antimicrobial stewardship.

Prevalence and risk factors for nasal carriage of Staphylococcus aureus in children attending anganwaries (preschools) in Ujjain, India

BackgroundChildren with nasal carriage of S. aureus play an important role in community spread of S. aureus and methicillin-resistant S. aureus (MRSA). Screening the nasal carriage isolates of S. aureus for antibiotic resistance patterns will provide guidelines for empiric therapy of community-acquired infections. The aim of the present study was to determine the prevalence of S. aureus and MRSA and it’s in vitro antibiotic susceptibility pattern among children in anganwaries (preschools) of Ujjain city India. This work is an extension to our previous publication in BMC Pediatrics (http://www.biomedcentral.com/1471-2431/10/100).MethodsA prospective study was done among children aged 1 to 6 years of age attending 100 anganwaries chosen purposely for the study to evenly cover the city. From each anganwari 10 children were randomly selected for nasal swabbing. Children having pyoderma were not included. Information on risk factors for nasal colonization was collected using a pre-tested questionnaire. Swabs from anterior nares were plated on 5% sheep blood agar. Antibiotic susceptibility tests were performed using Kirby-Bauer’s disc diffusion method according to performance standards of Clinical and Laboratory Standard Institute guidelines.ResultsA total of 1002 children were included in the study. The prevalence of S. aureus nasal carriage was 35% (95% confidence interval CI 32.07 to 37.98) and that of MRSA nasal carriage was 29% (95% CI 24.28 to 33.88). The factors that were independently associated with nasal carriage of S. aureus were: “age-group” i.e. as the age increased beyond the age of 2 years the OR of nasal carriage decreased, “family size of more than 10 members” OR 2.59 (95% CI 1.53-4.37; P < 0.001), and protein energy malnutrition Grade 3 or 4 (OR 1.40, 95% CI 1.04-1.90; P = 0.026). The resistance pattern of S. aureus and MRSA showed resistance not only to single antibiotic class but co-resistance and multi-drug resistance was also common.ConclusionsThe high rates of nasal carriage of S. aureus and MRSA and presence of resistance to commonly used antibiotics are disturbing. Antibiotic stewardship programmes that promote judicious use of antibiotic along with strategies to prevent community spread of S. aureus are urgently needed.

ASSOCIATION BETWEEN STAPHYLOCOCCUS AUREUS IN THE HOME EVIRONMENT AND DECREASED LUNG FUNCTION IN ASTHMATIC CHILDREN IN BARBADOS

Background and Aims. Staphylococcus aureus, a gram-positive bacterium, can survive in the environment for weeks to months. While asthma is a known risk factor for nasal colonization with methicilli...

Nasal Carriage and Antimicrobial Susceptibility of Staphylococcus aureusin healthy preschool children in Ujjain, India

BackgroundThere is increasing evidence that community acquired S. aureus infections are spreading among healthy children. Nasal colonization with S. aureus plays pivotal role in the increasing prevalence of resistant community acquired S. aureus infections worldwide. A regular surveillance system is important in ensuring quality of patient care. The aim of the study was to assess the prevalence of and the factors associated with nasal carriage of S. aureus and its antibiotic sensitivity pattern among healthy children in Ujjain, India.MethodsA prospective study was done in paediatric outpatient clinics of R.D. Gardi medical college Ujjain, India. Healthy children from 1 month to 59 months of age were included. Information on previously known risk factors for nasal colonization was collected using a pre-tested questionnaire. Swabs from anterior nares were collected and transported in Amies transport media with charcoal and cultured on 5% sheep blood agar. Antibiotic sensitivity tests were performed using Kirby Bauer's disc diffusion method according to performance standards of Clinical and Laboratory Standard Institute guidelines.ResultsOf the 1,562 children from 1-month up-to five years of age included in the study 98 children tested positive for nasal carriage of S. aureus. The prevalence of nasal carriage of S. aureus was 6.3% (95% CI 5.1-7.5) out of which 16.3% (95% CI 8.9-23.8) were methicillin-resistant S. aureus (MRSA). The factors associated with nasal carriage were "child attending preschool" (OR 4.26, 95% CI 2.25-8.03; P = 0.007) or "school" (OR 3.02, 95% CI 1.27-7.18; P < 0.001) and "family size more than 10 members" (OR 2.76 95% CI 1.06-7.15; P = 0.03). The sensitivity pattern of isolated S. aureus showed resistance to commonly used oral antibiotics while resistance to glycopeptides was not noted.ConclusionsWe found a relatively low rate of nasal carriage of S. aureus in children below five years when compared to children of older age groups in India. Yet, prevalence of MRSA was relatively high.

Molecular analysis and risk factors for nasal colonization with methicillin-resistant Staphylococcus aureus among community individuals attending a Family Health Care Program in Rio de Janeiro, Brazil

tests for detection of Mycobacteria and Fungi in urine specimens. Methods: Study was done in Department of Microbiology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India, from October 2005 to September 2007. Urine samples of 50 patients with clinical suspicion of Tubercular and Fungal etiology of Urinary tract infection of immunocompromised patients [Diabetes mellitus (14), AIDS (13), Renal transplant recipient (09), Malignancies (07), End stage renal disease/ Chronic renal failure (06), Systemic lupus erythematosus (01)] & 50 apparently immunocompetant patients were taken as diseased control. For Mycobacteria microscopy (Ziehl-Neelsen staining), Culture (Lowenstein Jensen Medium and BACTEC medium), PCR and NAP test were done. For Fungus microscopy (Direct wet mount, Gram’s stain), Culture (Sabouraud’s Dextrose Agar), Germ tube test, Corn meal agar, Sugar Fermentation & assimilation test were done. Culture was considered as gold standard. Results: Out of 50 immunocompromised patients, 7(14%) were positive for mycobacteria [MTBC 5(10%), MOTT 2(4%)] and 10(20%) were positive for fungi [C. albicans 4(8%), C. glabrata 4(8%) and C. tropicalis 2(4%)]. Out of 50 apparently immunocompetant patients (diseased control), 4(8%) were positive for mycobacteria [MTBC 3(6%), MOTT 1(2%)] and 3(6%) were positive for fungi [C. albicans 2(4%) and C. tropicalis 1(2%)]. Sensitivity and specificity were 71.42%, 90.69% of Ziehl-Neelsen stain, 88%, 100% of Lowenstein Jensen culture, 57%, 100% of PCR for Mycobacteria, 80%, 100% respectively for wet mount for fungi. Conclusion: Incidence of mycobacterial/fungal infection in immunocompromised patients is more then to immunocompetent individuals and with immunocompromised conditions, urinary tract infection should be screened for mycobacterial and fungal pathogens.

Nasal carriage of inducible dormant and community-associated methicillin-resistant Staphylococcus aureus in an ambulatory population of predominantly university students

BackgroundWe studied risk factors for nasal colonization with inducible dormant methicillin-resistant Staphylococcus aureus (ID-MRSA) and community-associated MRSA (CA-MRSA) in a cohort of predominantly university students. MethodsNasal surveillance cultures were performed in student health and ambulatory clinics. Molecular features were identified and risk factors for CA-MRSA and ID-MRSA colonization were determined by logistic regression. ResultsOf the 1000 participants, 89% (n = 890) were university students. Sixty-four percent were female, 59% Caucasian. The mean age was 23.5 years; 1.6% (n = 16) were CA-MRSA and 1.4% (n = 14) were ID-MRSA colonized. Fifteen (94%) of the CA-MRSA strains were PFGE type IV. pvl (Panton–Valentine leukocidin gene) positivity was 75% in CA-MRSA and 57% in ID-MRSA. ID-MRSA isolates were pulsed-field gel electrophoresis (PFGE) type I, 7%; type II, 14%; type V, 7%; and type IV, 71%. CA-MRSA SCCmec classification was 94% type IV and 6% type V. Risk factors for carriage of CA-MRSA were older age (OR 1.046, p=0.040) and dog ownership (OR 1.450, p=0.019). Single family home (OR 0.040, p=0.007) was a protective factor. There were no significant variables of association found for ID-MRSA colonization. ConclusionsID-MRSA/CA-MRSA colonization was low. Most isolates were PFGE types IV and II, pvl-positive and susceptible to several antibiotics. Older age and dog ownership were risk factors for CA-MRSA. Future studies are needed to assess the impact of ID-MRSA carriage.

Staphylococcus aureus Nasal Colonization in Preoperative Orthopaedic Outpatients

Nasal colonization with Staphylococcus aureus (SA) increases the risk of surgical site infection (SSI). We first (1) determined the prevalence of asymptomatic nasal colonization with SA, (2) assessed trends in methicillin resistance with time, (3) ascertained risk factors for nasal colonization; and (4) correlated SSI to nasal colonization status and procedure. We performed a cross-sectional analysis of SA nasal colonization among healthy preoperative orthopaedic outpatients between 2003-2005 who were within 2 weeks of surgery. Of 284 patients, 86 (30%) carried SA; of these, 81 (94%) were colonized with methicillin-sensitive and five (6%) with methicillin-resistant SA (MRSA). Total SA colonization increased from 25/78 (32%) in 2003 to 37/97 (38%) in 2005, and colonization with MRSA increased from 0/78 (0%) to four of 97 (4%), respectively. We found no associations between nasal carriage and demographics or procedures. Surgical site infection occurred in nine of 282 (3%), four of which were attributable to SA; these included 0/43 (0%) carriers who received decolonization with 2% mupirocin, two of 43 (4.7%) who declined decolonization, and two of 196 (1.0%) who were noncarriers. Nasal colonization with SA, including MRSA, among preoperative orthopaedic outpatients is increasing and their rates reflect community rates. Knowledge of colonization status may be important in decolonization, choosing perioperative or any subsequent empiric antibiotics.

Methicillin-resistant Staphylococcus aureus: prevalence, incidence and risk factors associated with colonization in Sri Lanka

We studied the prevalence of and risk factors for nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) on admission and the incidence and risk factors for nosocomial acquisition of MRSA in a 60 bed, male surgical unit in the National Hospital of Sri Lanka (NHSL). Nasal swab cultures were obtained from 271 patients admitted for routine surgery within 36 h of admission and repeated every other day until discharge. Clinical and epidemiological risk factors for colonization were compared between patients with MRSA at the time of admission or colonized after admission, and patients who were not colonized. MRSA was isolated from 35 patients (12.9%) with 20 (7.4%) colonized on admission and 15 (6%) acquiring MRSA after admission. Hospitalization within the previous year, antibiotic use within the previous two months, and transfer from another ward within the NHSL were associated with colonization with MRSA on admission. Risk factors for nosocomial acquisition of MRSA were the prophylactic and empiric use of antibiotics. The duration of antibiotic use and the duration of stay in hospital were significantly longer in patients who acquired MRSA. MRSA surveillance and control programmes in this unit would be more cost-effective if targeted at patients with these risk factors.

Population-based community prevalence of methicillin-resistant Staphylococcus aureus in the urban poor of San Francisco.

The study objective was to determine the prevalence and risk factors for nasal colonization with Staphylococcus aureus and methicillin resistance among the urban poor and to compare antibiotic resistance and genetic similarity to concurrently collected clinical isolates of methicillin-resistant S. aureus (MRSA). A population-based community sample of 833 homeless and marginally housed adults were cultured and compared with 363 clinical isolates of MRSA; 22.8% of the urban poor were colonized with S. aureus. Of S. aureus isolates, 12.0% were methicillin resistant. Overall prevalence of MRSA was 2.8%. Significant multivariate risk factors for MRSA were injection drug use (odds ratio [OR], 9.7), prior endocarditis (OR, 4.1), and prior hospitalization within 1 year (OR, 2.4). Resistance to antimicrobials other than beta-lactams was uncommon. Only 2 individuals (0.24%) with MRSA had no known risk factors. A total of 22 of 23 community MRSA genotypically matched clinical MRSA isolates, with 15 of 23 isolates identical to MRSA clones endemic among hospitalized patients.