The lack of sensitivity of methicillin resistant Staphylococcus aureus (MRSA) toward teicoplanin

A total of 60 methicillin resistant Staphylococcus aureus (MRSA) strains clinical samples in children were collected from cellulitis, abscess, and wound samples in Al-Hilla, and Babylon teaching hospital was identified to species level and antibiotic susceptibility testing with a VITEK-2 system. In the present study, 24 (40%) of MRSA isolates were community- acquired methicillin resistant Staphylococcus aureus (CA-MRSA), and 36 (60%) were hospitalized-acquired methicillin resistant Staphylococcus aureus (HA-MRSA). The results showed that 35 of female, and 25 of male of MRSA isolates, and these isolates were taken from 7 of infants aged less than 6 months, and 53 children aged between 6 months and 4 years of MRSA isolates. In the present study, antimicrobial susceptibility testing with the VITEK 2 system gave resistant to 10 and sensitive to 6 antibiotics to all bacterial isolates, but only 3(5%) of bacterial isolates were resistant to teicoplanin

Novel molecular analysis for characterization of staphylococcal cassette chromosome in a methicillin-resistant staphylococcus aureus isolated from Malaysian hospital.

Methicillin-resistant Staphylococcus aureus strains have appeared in countries worldwide and continue to be one of the most common hospital pathogens and it has become increasingly prevalent in community-acquired infections and provided strong evidence for the independent origins of health care-associated Methicillin-resistant Staphylococcus aureus and community-acquired. It has been shown that methicillin-susceptible S. aureus strains become MRSA strains by the acquisition of a staphylococcal cassette chromosome mec element carrying the mecA gene, which is responsible for methicillin resistance and has become essential for the characterization of Staphylococcus aureus clones in epidemiological studies. The objective of this study to identify the staphylococcal cassette chromosome mec types of methicillin-resistant Staphylococcus aureus isolated from different Malaysian Hospitals. PCR amplification and sequencing analysis were performed to determine the SCCmec type of MRSA. The present research successfully established molecular characteristics of local MRSA contribute as initial database of these isolates in order to fully understand the epidemiology, microbiology and pathophysiology of these infections

Occurrence of Multidrug Resistant Methicillin-Resistant Staphylococcus aureus and Methicillin-Susceptibility Staphylococcus aureus in Chon Buri Province

บทคัดย่อ การศึกษาครั้งนี้มีจุดประสงค์เพื่อศึกษาความไวและแบบแผนการดื้อยาต้านจุลชีพของ Methicillin-resistant Staphylococcus aureus (MRSA) จำนวน 103 ไอโซเลท และ Methicillin-susceptibility Staphylococcus aureus (MSSA) จำนวน 136 ไอโซเลท ที่แยกได้จากผู้ป่วยในโรงพยาบาลชลบุรี และโรงพยาบาลสมเด็จพระบรมราชเทวี ณ ศรีราชา จังหวัดชลบุรี พบว่า พบว่า MSSA ทุกไอโซเลทมีความไวต่อยาต้านจุลชีพ Oxacillin, Cefoxitin, Cefuroxime และ Vancomycin และเกือบทุกไอโซเลทดื้อต่อ Penicillin G และ Ampicillin ยกเว้น MSSA ที่แยกได้จากโรงพยาบาลชลบุรี คิดเป็น 2.88% เท่ากัน ส่วน MRSA ทุกไอโซเลทที่แยกได้จากทั้ง 2 โรงพยาบาล มีความไวต่อ Vancomycin และดื้อต่อ Penicillin G, Ampicillin, Oxacillin และ Cefoxitin ส่วนแบบแผนการดื้อยาหลายชนิดของ MRSA ที่แยกได้จากโรงพยาบาลสมเด็จพระบรมราชเทวี ณ ศรีราชา และโรงพยาบาลชลบุรี พบว่ามีแบบแผนการดื้อยาต้านจุลชีพมากกว่า 6 ชนิดขึ้นไปมากที่สุด คิดเป็น 94.74% และ 97.62% ตามลำดับ และ MSSA มีแบบแผนการดื้อต่อยาต้านจุลชีพ 3 ชนิดมากที่สุด คิดเป็น 71.87% และ 60.58% ตามลำดับ จากการศึกษาครั้งนี้ชี้ให้เห็นว่าทั้ง MRSA และ MSSA ที่คัดแยกมาจากจังหวัดชลบุรีมีการดื้อต่อยาต้านจุลชีพหลายชนิด  โดยเฉพาะอย่างยิ่ง MRSA ดื้อต่อยาต้านจุลชีพในกลุ่มเบต้าแลคแตมมากที่สุด คำสำคัญ: Methicillin-resistant Staphylococcus aureus (MRSA)Methicillin-susceptibility Staphylococcus aureus (MSSA) ความไวต่อยาต้านจุลชีพ การดื้อยาปฏิชีวนะหลายชนิด ABSTRACTThe aim of this study was to investigate the antimicrobial susceptibility and pattern of multidrug resistance of methicillin-resistant Staphylococcus aureus (MRSA; 103 isolates) and methicillin-susceptibility Staphylococcus aureus (MSSA; 136 isolates) recovered from the patients in Chon Buri Hospital and Queen Savang Vadhana Memorial Hospital in Chon Buri Province. All isolates of MSSA were susceptible to oxacillin, cefoxitin, cefuroxime and vancomycin. Almost all MSSA isolates were resistant to penicillin G and ampicillin, except 2.88% MSSA isolated from Chon Buri Hospital. All MRSA isolates recovered from both hospitals exhibited susceptibility to vancomycin and were resistant to penicillin G, ampicillin, oxacillin and cefoxitin. In case of antimicrobial resistant pattern of S. sureus isolated from Queen Savang Vadhana Memorial Hospital and Chon Buri Hospital, MRSA showed the highest resistance to more than 6 types of antimicrobial agents (94.74% and 97.62%, respectively) while MSSA presented the highest resistance to 3 types of those agents (71.87% and 60.58%, respectively). This finding indicated that both MRSA and MSSA collected from hospitals in Chon Buri Province were resistant to multiple antimicrobial agents, particularly, beta-lactam antibiotics resistance of MRSA.Keywords: Methicillin-resistant Staphylococcus aureus (MRSA), Methicillin-susceptibility Staphylococcus aureus (MSSA), Antimicrobial susceptibility, Multidrug resistan

PREVALENCE AND ANTIMICROBIAL SUSCEPTIBILITY OF METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS AND COAGULASE-NEGATIVE STAPHYLOCOCCI IN A TERTIARY CARE HOSPITAL.

Background: Globally nosocomial infection is a major problem. Prevalence and antibiotic resistance of methicillin-resistant Staphylococcus aureus (MRSA) strains is reported to be increasing globally. MRSA and methicillin resistant coagulase negative staphylococci (MRCoNS) are the important agents causing nosocomial infections. Objective: The study was conducted to find out the prevalence rate of MRSA and MRCoNS and antibiotic susceptibility pattern. Materials and Methods: This was a retrospective study conducted from June 2011 to November 2012 in a tertiary care hospital in south India. All isolates were identified by Clinical and Laboratory Standards Institute (CLSI) guidelines and antibiotic susceptibility pattern determined by modified Kirby Bauer disc diffusion method. The information was recorded and analyzed using Microsoft Excel (2007 version). Results: A total of 210 Staphylococcus strains were isolated from various clinical samples, 180 were coagulase positive staphylococcus (CoPS) and 30 were coagulase negative staphylococcus (CoNS). Among 180 CoPS, 58 (32.22%) were Methicillin resistant and among CoNS, 12 (40%) were methicillin resistant. In MRSA maximum resistance was seen with oxacillin (93.2%) and least with vancomycin (3.5%). In MRCoNS maximum resistance was seen with oxacillin (91.7%) and least with vancomycin (0 %). Conclusion: There is need for continuous monitoring of the antimicrobial susceptibility pattern of methicillin staphylococcus aureus and methicillin resistant coagulase negative staphylococci for the selection of appropriate therapy, developing the antibiotic policy and for limiting the use of powerful antibiotics. Key words: Methicillin-resistant Staphylococcus aureus (MRSA), Methicillin resistant coagulase negative staphylococci, Vancomycin, Nosocomial infection, Susceptibility patter

Clinical, Microbiological, and Genetic Characteristics of Heteroresistant Vancomycin-Intermediate Staphylococcus aureus Bacteremia in a Teaching Hospital

The emergence of vancomycin intermediate Staphylococcus aureus (VISA) and heterogeneous VISA (hVISA) is of major concern worldwide. Our objective was to investigate the prevalence, phenotypic and molecular features of hVISA strains isolated from bacteremic patients and to determine the clinical significance of the hVISA phenotype in patients with bacteremia. A total of 104 S. aureus blood isolates were collected from a teaching hospital of Argentina between August 2009 and November 2010. No VISA isolate was recovered, and 3 out of 92 patients (3.3%) were infected with hVISA, 2 of them methicillin-resistant S. aureus (MRSA) (4.5% of MRSA). Macro Etest and prediffusion method detected 3/3 and 2/3 hVISA respectively. Considering the type of bacteremia, the three cases were distributed as follows: two patients had suffered multiple episodes of bacteremia (both hVISA strains recovered in the second episode), while only one patient had suffered a single episode of bacteremia with hVISA infection. MRSA bloodstream isolates exhibiting the hVISA phenotype were related to HA-MRSA Cordobes clone (ST5-SCCmec I-spa t149) and MRSA Argentinean pediatric clone (ST100-SCCmec IVNV-spa t002), but not to CA-MRSA-ST30-SCCmec IV-spa t019 clone that was one of the most frequent in our country. Although still relatively infrequent in our hospital, hVISA strains weresignificantly associated with multiple episodes of bacteremia ( p = 0.037) and genetically unrelated.Fil: Di Gregorio, Sabrina Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Perazzi, Beatriz Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Martinez Ordoñez, Andrea. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Bioquímica Clínica; ArgentinaFil: de Gregorio, Stella. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Focoli, Mónica. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Lasala, María Beatriz. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Garcia, Susana. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Vay, Carlos Alberto. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Famiglietti, Angela María Rosa. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Mollerach, Marta Eugenia. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentin

Death associated to methicillin resistant staphylococcus aureus ST8 infection in two dolphins maintained under human care, Italy

The present study describes the isolation of Methicillin-resistant Staphylococcus aureus (MRSA) from respiratory tract of 2 dolphins of different origin, a stranded juvenile Risso's dolphin (Grampus griseus) and a captive born common bottlenose dolphin (Tursiops truncatus) calf, which died in the same institution at 1-month distance from the other. A complete microbiological and genetic investigation confirmed the presence of MRSA clone-complex 8, sequence type (ST) 8, spa-type t008 in both individuals. This strain differs from the one previously reported in walruses and dolphins and has never been described in dolphins before, but it is randomly isolated from Italian human patients. Vertical transmission of the infection may also occurs in other species and considering the description and location of the pathological lesions, this seems to be the most likely route of transmission implied in the young bottlenose dolphin. Staphylococcus aureus is known as an opportunistic agent, usually secondary to other pathogens, but its multiple antibiotic resistance and its zoonotic implications suggest a thorough and strict application of animal management hygiene protocols

The Frequency of MRSA carriers in health care workers in Gorgan, North of Iran

Methicillin resistant Staphylococcus aureus (MRSA) is one of the most important pathogen in hospitals. Healthcare personnel are the main source of nosocomial infections and identification and control of MRSA carriers can reduce incidence of infections. The aim of this study was to determine the frequency of methicillin resistant Staphylococcus aureus (MRSA) and their antibiotic susceptibility profile among healthcare workers in Gorgan located in northern Iran. Three hundred and thirty three of healthcare workers were participated in this cross-sectional study in 2010. Samples were taken with sterile cotton swabs from both anterior nares. Swabs were plated onto Mannitol salt agar. S. aureus were identified by Gram stain, Catalase, Coagulase and DNase tests. MIC (micro dilution broth) method was used to determine resistance of strains to methicillin. Antimicrobial susceptibility pattern to other antibiotics was performed by diffusion method. Frequency of S. aureus and MRSA carriers among healthcare workers was 24% (80.33) and 3% (10.33) respectively. MIC of isolates was varied between 0.5 and 65.31 (39%) of cases were showed MIC of intermediate that ranged between 4 and 8. Penicillin and Imipenem resistance were seen in 97.5% and 1.4% of isolated S. aureus strains, respectively. Frequency of S. aureus carriers in healthcare workers in our area was median in compare with other region in Iran but the MRSA carriage in healthy staff was lower than most part of Iran. It would be considering to monitor healthy carrier staff because of high rate intermediate MIC in this group to prevent conversion to MRSA

Prevalence of qacA/B genes and mupirocin resistance among methicillin-resistant Staphylococcus aureus (MRSA) isolates in the setting of chlorhexidine bathing without mupirocin

OBJECTIVE: We aimed to determine the frequency of qacA/B chlorhexidine tolerance genes and high-level mupirocin resistance among MRSA isolates before and after the introduction of a chlorhexidine (CHG) daily bathing intervention in a surgical intensive care unit (SICU). DESIGN: Retrospective cohort study (2005–2012) SETTING: A large tertiary-care center PATIENTS: Patients admitted to SICU who had MRSA surveillance cultures of the anterior nares METHODS: A random sample of banked MRSA anterior nares isolates recovered during (2005) and after (2006–2012) implementation of a daily CHG bathing protocol was examined for qacA/B genes and high-level mupirocin resistance. Staphylococcal cassette chromosome mec (SCCmec) typing was also performed. RESULTS: Of the 504 randomly selected isolates (63 per year), 36 (7.1%) were qacA/B positive ( + ) and 35 (6.9%) were mupirocin resistant. Of these, 184 (36.5%) isolates were SCCmec type IV. There was a significant trend for increasing qacA/B (P= .02; highest prevalence, 16.9% in 2009 and 2010) and SCCmec type IV (P< .001; highest prevalence, 52.4% in 2012) during the study period. qacA/B( + ) MRSA isolates were more likely to be mupirocin resistant (9 of 36 [25%] qacA/B( + ) vs 26 of 468 [5.6%] qacA/B(−); P= .003). CONCLUSIONS: A long-term, daily CHG bathing protocol was associated with a change in the frequency of qacA/B genes in MRSA isolates recovered from the anterior nares over an 8-year period. This change in the frequency of qacA/B genes is most likely due to patients in those years being exposed in prior admissions. Future studies need to further evaluate the implications of universal CHG daily bathing on MRSA qacA/B genes among hospitalized patients

Low MRSA prevalence in horses at farm level

Background: In Europe, methicillin-resistant Staphylococcus aureus (MRSA) belonging to the clonal complex (CC) 398 has become an important pathogen in horses, circulating in equine clinics and causing both colonization and infection. Whether equine MRSA is bound to hospitals or can also circulate in the general horse population is currently unknown. This study, therefore, reports the nasal and perianal MRSA screening of 189 horses on 10 farms in a suspected high prevalence region (East-and West-Flanders, Belgium). Results: Only one horse (0.53%) from one farm (10%) tested positive in the nose. It carried a spa type t011-SCCmecV isolate, resistant to beta-lactams and tetracycline, which is typical for livestock-associated MRSA CC398. Conclusion: In the region tested here, horses on horse farms seem unlikely to substantially contribute to the large animal associated ST398 MRSA reservoir present at intensive animal production units

Community-associated methicillin-resistant Staphylococcus aureus skin and soft tissue infections in a pediatric hospital in Argentina

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) emerged at the Pediatric Hospital of Misiones Province, north Argentina, in 2003 as a cause of community-acquired (CA) infections, mostly associated with skin and soft tissue infections (SSTIs). This study aimed to assess the microbiological, epidemiological, and clinical features of CA-MRSA SSTIs treated at the hospital. Methodology: From 2003 through 2006, a longitudinal study on CA-MRSA SSTIs was conducted. Clinical, bacteriological, and molecular data were collected and analyzed by multiple correspondences and cluster analysis (MCCA). Results: A total of 138 children were enrolled; 55.8% of the children required hospitalization. The main clinical presentation was abscesses (51%). Antibiotic therapy in the previous six months was registered in 41% of the patients, and 72% of the patients had relatives with similar symptoms. Resistance to non-b-lactam antibiotics was found in less than 12% of patients. All 44 isolates carried staphylococcal cassette chromosomemec (SCCmec) type IV, and 30/44 had Panton-Valentine leucocidin (PVL) coding genes. Six pulsed-field gel electrophoresis (PFGE) patterns were detected from 17 isolates. MCCA hierarchic classification resulted in four distinctive patient classes (new variable). No relationship could be observed regarding the PVL detection, as PVL (+) isolates were detected in all classes; the same lack of significance was observed concerning the distribution of resistance to non-β-lactam antibiotics. Conclusions: This study increases the understanding and knowledge about CA-MRSA skin and soft tissue infections in pediatric patients. Continuous efforts should be made to control this significant public health problem.Fil: Von Specht, Martha Helena. Provincia de Misiones. Ministerio de Salud de la Provincia de Misiones. Hospital Publico Provincial de Pediatria de Autogestion Dr. Fernando Barreyro; Argentina. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; ArgentinaFil: Gardella, Noella Mariel. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Ubeda, Clotilde. Dirección Nacional del Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr.C.G.Malbran". Instituto Nacional de Epidemiologia; ArgentinaFil: Grenon, Sandra Liliana. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina. Provincia de Misiones. Ministerio de Salud de la Provincia de Misiones. Hospital Publico Provincial de Pediatria de Autogestion Dr. Fernando Barreyro; ArgentinaFil: Gutkind, Gabriel Osvaldo. Dirección Nacional del Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr.C.G.Malbran". Instituto Nacional de Epidemiologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mollerach, Marta Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Dirección Nacional del Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud "Dr.C.G.Malbran". Instituto Nacional de Epidemiologia; Argentin