Prevalence Of Methicillin-resistant Coagulase-negative Staphylococci Research Articles

Methicillin-Resistant Coagulase Negative Staphylococci and Their Antibiotic Susceptibility Pattern from Healthy Dogs and Their Owners from Kathmandu Valley.

This cross-sectional study was designed to identify information on the frequency, antimicrobial resistance and species diversity of methicillin-resistant coagulase negative staphylococci (MRCoNS) among pet dogs and humans within households. Fifty five nasal swabs each from dogs and their owners were collected. MRCoNS were identified based on gram staining, culture on mannitol salt agar, biochemical tests, and mecA gene amplification. The antibiotic susceptibility of the isolates was assessed by a disc diffusion test. Uniplex and multiplex polymerase chain reaction (PCR) were employed for the species identification of MRCoNS and SCCmec typing, respectively. Species were further confirmed by MALDI-TOF-MS. The prevalence of MRCoNS was 29% in dog owners and 23.6% in dogs. Four different species of MRCoNS, Staphylococci saprophyticus (48.3%), S. haemolyticus (24.1%), S. warneri (17.2%), and S. epidermidis (10.3%), were detected. Two isolates each from dog owners and dogs showed a constitutive resistance to macrolide-lincosamide-streptogramin B (cMLSB) resistance, eight isolates each from dogs and their owners showed a macrolide-streptogramin B (MSB) resistance, and only two isolates from dog owners revealed an inducible resistance to macrolide-lincosamide-streptogramin B (iMLSB) resistance. SCCmec types were SCCmec type IV (55.2%), SCCmec type V (24.1%), SCCmec III (10.3%), SCCmec II (3.4%); two isolates were non-typable. MRCoNS are prevalent and genetically diverse in companion animals and humans. Different species of MRCoNS were found in dogs and their owners.

Prevalence of methicillin-resistant coagulase-negative staphylococci among Egyptian patients after surgical interventions.

Coagulase-negative staphylococci (CoNS) are frequently isolated from wound infections. There are limited data examining the prevalence of methicillin-resistant CoNS (MRCoNS) among Egyptian patients after surgery. Thus, we studied 208 hospitalised patients, who had skin and soft tissue infections (SSTIs) due to various causes. Samples were cultured for isolation and identification of CoNS and isolates were screened for susceptibility against 23 different antimicrobials. Out of 241 Staphylococcal isolates, 114 (47.3%) were CoNS. The prevalence of MRCoNS among surgical site infection, diabetic foot, abscess, and burn patients was 13.4%, 11.5%, 15.6%, and 10.3%, respectively. The lowest resistance of the 27 identified MRCoNS isolates was to vancomycin, amikacin and gatifloxacin (7% each). We conclude that CoNS isolates are major pathogens associated with wound infections at our institution and MRCoNS probably poses a substantial threat for patients in Egypt, though most MRCoNS isolates demonstrated susceptibility to vancomycin.

Study of methicillin-resistant Staphylococcus aureus among patients admitted in tertiary care rural hospital

Background: Methicillin-resistant Staphylococcus aureus (MRSA) has become a major health-care issue today in community hospitals, long-term care facilities, and tertiary care hospitals. Colonization and infection by Staphylococcus aureus are known to be significantly associated with infection among hospitalized patients. MRSA nasal carriage among hospital patients on admission will increase the likelihood of MRSA infection during the same episode of hospitalization. Objectives: The study was carried out to know the prevalence of MRSA and methicillin-resistant coagulase-negative staphylococci (MRCoNS) colonization from nasal swabs, gender-wise, age-wise, and stay-wise distribution of MRSA and MRCoNS. \ Materials and Methods: A prospective cross-sectional study was carried out from the period of December 2013 to April 2014. Nasal swabs were collected from 229 patients, who were admitted for more than 48 h admission in the hospital from various clinical departments. Informed consent was obtained from the patients or their relatives. Results: Of 229 patients, S. aureus was isolated in 63 (27.51%) and coagulase-negative S. aureus in 91 (39.74%). The prevalence of MRSA was 9.17% and MRCoNS - 11.79%. Colonization was seen more in males. Higher prevalence of MRSA was seen in 60 years. Higher prevalence of MRSA was seen in the 1st week of admission and higher prevalence of MRCoNS was noted from the 2nd week onward. Conclusion: We observed higher prevalence of MRSA in the 1st week of admission and from the 2nd week onward MRCoNS among the hospitalized patients. The higher prevalence of MRSA was also seen in the under-fives followed by geriatric age group who are vulnerable. Hence, we strongly advised that every patient should be screened for MRSA at the time of admission to reduce the burden of MRSA infection during hospitalization.

High prevalence of methicillin-resistant coagulase-negative staphylococci isolated from a university environment in Thailand.

The present study was conducted to isolate and characterize the molecular epidemiology of the methicillin-resistant staphylococci in the general university environment, where all five locations; the library, restrooms, canteens, computer rooms and outdoor surfaces, are in common use by a large population of students. We used Mannitol Salt Agar (MSA) supplemented with 4 μg/ml of oxacillin to screen the methicillin-resistant staphylococci. The species level was identified by PCR of rdr (Staphylococcus epidermidis), groESL (Staphylococcus haemolyticus) and nuc (Staphylococcus aureus and Staphylococcus warneri) genes and DNA sequencing of tuf and dnaJ genes. The susceptibility patterns of the isolates were determined using the disk diffusion method. Antibiotic and disinfectant resistance genes, together with SCCmec types, were detected by the PCR method. The methicillin resistant-staphylococci were isolated from 41 of 200 samples (20.5%), and all of them were found to be methicillin-resistant coagulase negative staphylococci (MR-CoNS). The library had the highest percentage of contamination, with 43.3% of the samples found to be contaminated. All isolates belonged to 6 different species including S. haemolyticus, S. epidermidis, S. warneri, S. cohnii, S. saprophyticus and S. hominis. The antimicrobial resistance rates were highest against penicillin (100%), then cefoxitin (73.1%), erythromycin (73.1%) and oxacillin (68.3%). Altogether, the isolates were approximately 61.0% multidrug resistant (MDR), with the S. epidermidis isolates being the most multidrug resistant. The prevalence of the qacA/B gene was detected in 63.4% of the isolates, and SCCmec could be typed in 43.9% (18/41) of the isolates. The type range was: II (n = 1), IVd (n = 1), I (n = 2), V (n = 6), IVa (n = 8) and untypeable (n = 23). This result indicates that these university environments are contaminated with methicillin-resistant coagulase negative staphylococci that carry various SCCmec types and high rate of disinfectant resistance genes. [Int Microbiol 20(2):65-73 (2017)].

Genotypic Diversity of Methicillin-Resistant Coagulase-Negative Staphylococci Isolated from Inpatients and Outpatients.

We investigated the prevalence of methicillin-resistant coagulase-negative staphylococci (MRCoNS) isolated from hospitalized patients and outpatients (OP). Out of 350 staphylococcal isolates collected from three hospitals, 190 were coagulase-negative staphylococci (CoNS). These isolates were subjected to antimicrobial susceptibility tests, detection of mecA, and pulsed-field gel electrophoresis (PFGE) typing. Among the 190 isolated CoNS, Staphylococcus epidermidis (47.3%) and Staphylococcus haemolyticus (44.2%) were the most prevalent species. Other CoNS species that were isolated were Staphylococcus saprophyticus (2.1%), Staphylococcus warneri (2.1%), Staphylococcus simulans (1.6%), Staphylococcus capitis (1.1%), Staphylococcus schleiferi (1.1%), and Staphylococcus hominis (0.5%). The rate of resistance to methicillin was 60% with 58 (50%) S. epidermidis and 55 (49%) S. haemolyticus. The rate of resistance to 13 antibiotics tested with the lowest and highest to chloramphenicol and penicillin, respectively. High clonal diversity with different PFGE patterns was obtained for methicillin-resistant S. epidermidis and S. haemolyticus by 32 and 31 types, respectively. Our results indicated that the dissemination of MRCoNS is widespread in Tehran. The majority of these isolates showed distinct genotyping patterns. At the same time, the common patterns were found among the MRCoNS obtained from outpatient and inpatient isolates, suggestive of an epidemiological link.

Peritonitis in Peritoneal Dialysis Patients in Uruguay

Uruguay is a South American country (3241003 inhabitants) where renal replacement treatment is universally available. The aim of this study was to analyze the incidence and outcome of peritonitis, and the causative organisms and their sensitivity, in order to recommend an empiric initial antibiotic treatment. A retrospective descriptive study of all peritonitis during the period 2004-2005 was performed (144 peritonitis, 44% due to gram-positive bacteria). We conclude that the high prevalence of methicillin-resistant coagulase-negative staphylococci justifies the use of vancomycin in the national empiric initial antibiotic protocols.