Coagulase gene polymorphism of Staphylococcus aureus isolates: A study on dairy food products and other foods in Tehran, Iran

Coagulase is considered as a major determinant factor for the identification of Staphylococcus aureus strains.The 3-end coding region of the coagulase(coa)gene contains a series of 81-bp tandem repeats,which differ in the number and location of enzymatic restriction sites among different isolates.coa PCR-RFLP has been used widely to type S.aureus isolates in epidemiological studies.The current study was conducted to investigate the coagulase gene polymorphisms in S.aureus isolated from various food samples using an in house PCR-RFLP method.A total of 100 strains of S.aureus were isolated from food samples.Isolates were typed by PCR-RFLP analysis using NdeI restriction digestion of the coagulase gene PCR products.Results showed that amplification of coagulase genes from S.aureus produced different PCR products.The isolates were grouped into 18 genotypes using RFLP analysis results of the genes.In this study,the S.aureus isolates have been shown to include more than one coagulase genotype,but only had a few coa genotypes predominated.

Characteristics of Archived Coagulase Negative <i>Staphylococci</i>Isolates at a University Hospital, Nairobi, Kenya

Background: Coagulase negative Staphylococci (CoNS) are normal inhabitants of the skin and mucous membranes and thus have been dismissed for a long time as culture contaminants even if they have been isolated from sterile specimens. The risk factors for CoNS infections include patients who are immunocompromised, implanted with foreign bodies or with indwelling devices. The aim of this study was to determine the antimicrobial susceptibility patterns and presence of mecA gene in methicillin resistant CoNS isolated in a teaching and referral hospital in Kenya. Methodology: This was a cross sectional retrospective study. Archived isolates were sub-cultured on 5% sheep blood agar. Speciation and antimicrobial susceptibility patterns were performed by Vitek2 technique. The presence of mecA gene was determined by (PCR). Results: A total of seven species were identified with Staphylococcus epidermidis having the highest percentage at 45.4% and Staphylococcus warneri with the lowest at 2.6%. High resistance to antibiotics that were tested was observed regardless of the source of the isolate. MecA gene was found in 90% of the isolates. Conclusion: Coagulase negative Staphylococci exhibited high levels of resistance generally. Most of the isolates carried the mecA gene. Despite some of the isolates being resistant to Cefoxitin, the mecA gene was not found. There is a possibility that methicillin resistance in these isolates is mediated using a different mechanism.

Coagulase Negative Staphylococcus Causes Catheter Associated Bacteriemia in a Patient with Esophagus Adenocarcinome

We report a case of a man suffering esophagus adenocarcinome who acquired catheter associated bacteriemia caused by a coagulase negative Staphylococcus. This CoNS was sensible to linezolid, teicoplanine, vancomycin and rifampicin. This information was relevant for antibiotherapy planning. The patient was successfully treated with teicoplanin together with the catheter exchange. In conclusion, infections should be treated with adequate doses and duration of antibiotics together with catheter exchange. Pre-emptive measurements in the cancer patient and establishing the most adequate treatment are imperative for obtaining good results.

Coagulase Gene Typing with Emphasis on Methicillin-Resistance Staphylococci: Emergence to Public Health

Emerging antimicrobial resistance among CNS is a concern in veterinary and human medicine. Coagulase test is considered as the key test to differentiate staphylococci to two groups, coagulase positive staphylococci (CPS) and coagulase negative staphylococci (CNS). A total of 200?Staphylococci?strains were isolated with percentage 66.7% (200/300) from quarter milk samples. The total of?S. aureus?strains are 70 with percentage 35% (70/200). Among 70 strains of?S. aureus, 30 strains are coagulase positive?S. aureus?with percentage 43% (30/70) and coagulase negative?S. aureus?57% (40/70). CNS other than?S. aureus?was detected with percentage 65% (130/200) from subclinical mastitic cows. We examine sixty isolates of staphylococci recovered from subclinical mastitis in dairy cattle which divided as ten isolates of coagulase positive?S. aureus?(CP?S. aureus), ten isolates of coagulase negative?S. aureus(CN?S. aureus) and forty isolates of coagulase negative staphylococci (CNS) which identified using API-Staph Kits as?S. chromogenes,?S. simulans,?S. haemolyticus,?S. epidermidis?and?S. cohnii.?The genotypic detection of?coa?gene and?mecA gene was screened in CP?S. aureus, CN?S. aureus?and CNS.

Diversity and Distribution of Staphylococcal Chromosomal Cassettes Mec (SCCmec) Types I, II and III in Coagulase-Negative Staphylococcal Strains Isolated from Surfaces and Medico-Technical Materials of the University Hospital of Abomey-Calavi/Sô-Ava

The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA+ strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA− SCCmec+ methicillin-resistant strains deserve to be sequenced for further studies.

Determination of antimicrobial resistance profile and inducible clindamycin resistance of coagulase negative staphylococci in pediatric patients: the first report from Iran

Background:Currently,coagulase negative staphylococci(CoNS)have got much attention as a serious health problem especially in neonates and children.High incidence of antibiotic resistance,in particular methicillin resistance,has complicated the treatment of these organisms.The aim of this study is to determine the susceptibility to different antimicrobial agents and the prevalence of macrolides-lincosamides-streptogramins B(MLS_(B))resistance in CoNS isolates obtained from pediatric patients.Methods:Totally 157 CoNS isolates from various clinical samples were examined for antibiotic resistance using disk diffusion and E-test methods.Double-disk test was applied to detect constitutive and inducible MLSB resistance(cMLS_(B)and iMLS_(B))phenotypes.Results:Resistance to methicillin was seen in 98(62.4%)isolates.All isolates were susceptible to vancomycin and linezolid.The prevalence of resistance to antibiotics tested was as follows:fusidic acid(n=58,36.9%),gentamicin(n=73,46.5%),ciprofloxacin(n=81,51.6%),clindamycin(n=112,71.3%),erythromycin(n=129,82.2%)and trimethoprim/sulfamethoxazole(n=133,84.7%).iMLS_(B)phenotype was seen in 14(8.9%)isolates,and 18(11.5%)and 98(62.4%)isolates showed MS and cMLS_(B)phenotypes,respectively.We observed that high overall antibiotic resistance rates were associated significantly with methicillin resistance.Conversely,iMLS_(B)phenotype was correlated neither with methicillin resistance nor with invasiveness.Conclusion:Given the similarity observed between the prevalence of iMLS_(B)and MS phenotypes,the performance of disk diffusion induction test is strongly recommended in our region.

Identification of Microbes in Patients with Lumbar Disc Herniation

Apart from the conventional factors, recent evidences have suggested that lumbar disc herniation (LDH) is also associated with microbes, which is completely ignored in the management of patients with disc prolapse and disc degeneration. Therefore, the present study was carried out to identify the different microorganisms in subjects with LDH. Subjects (n = 101) who were confirmed for LDH with Magnetic Resonance Imaging and undergoing lumbar discectomy, were recruited in this study. Standard protocols for disinfection of the skin and surgical instruments were adhered. Skin scrapings, muscle biopsies and portion of the inter-vertebral disc were transferred into individually labeled Robertson’s cooked meat enrichment broth for anaerobic identification. Remaining portions of the excised disc material and muscle biopsy were taken for aerobic identification. Anaerobic isolates were identified using Gram stain and catalase test while the species identification was done by RapID ANA II ID kit. Gram stain, catalase test, DNase test and coagulase tests were used for identification of aerobic bacteria. Study confirmed 6/101 disc cultures (6%) with positive anaerobes and 12 disc cultures with coagulase negative Staphylococci spp. Among the anaerobes, two disc cultures were identified as Propionibacterium acnes and one as Gemella morbillorum. Due to slow growth, other three anaerobic cultures were not confirmed. However, they resembled the colony morphology of Gram positive bacilli. None of the control samples (skin and muscles) had any positive growth. The present study adds to the literature confirming the role of microorganisms in LDH. Present study newly identified Gemella morbillorum in the intervertebral tissue in addition to the previously reported microorganisms associated with LDH.

Staphylococcus cohnii: Not so innocuous

Staphylococcus cohnii is not known to causes meningitis. We present a case of mennigitis due to this organism. We are highlighting this case not only for its rarity but rapidity of worsening also. This report indicates that Staphylococcus cohnii are not as innocuous as once thought to be and these organisms should not be disregarded as possible skin contaminants. Before labelling them as contaminants their possible association with disease should be ruled out.

Risk Factors for Conjunctival Microorganism Colonization in Adults Undergoing Intraocular Surgery

Purpose: To assess prevalence of and risk factors for conjunctival colonization and types of organisms among adults undergoing elective intraocular surgery. Setting: Ha’Emek Medical Center, Afula, Israel. Methods: A prospective study conducted in the Ophthalmology Department at Ha’Emek Medical Center, Afula, Israel between May 1, 2006 and August 31, 2007. Included were adults undergoing elective intraocular surgeries. Conjunctival cultures were obtained from the lower fornix, prior to application of prophylactic decolonization treatment and were processed using routine microbiological techniques. Demographic, socioeconomic and medical data of our patient cohort were obtained from all participants. Results: Cultures were obtained from 501 patients. (Mean age 69.7 ± 12.0 years) of whom 52.1% were females. In 208 patients (40.5%) bacteria grew in conjunctival cultures, one type in 175 (34.9%) one, and two types in 28 (5.6%). In none fungi were isolated. Coagulase negative Staphylococcus was the most frequent bacteria isolated. By multivariate analysis, significant risk factors for conjunctival bacterial colonization were spring/summer seasons (OR 1.64, CI 1.15 - 2.36, P < 0.007), and showering on the day of the operation (OR 1.73, CI 1.11 - 2.69, P < 0.01). Conclusions: In addition to previously known risk factors for conjunctival microorganism colonization, the present study found showering on the morning of the operation, possibly related to bacteria on towels or in the eyelids and lashes, and time of year (spring/summer) perhaps resulting from higher temperature and humidity related to the presence of conjunctival bacteria to be significant in adults undergoing intraocular surgery.