Bovine Coagulase-Negative Staphylococci: Biochemistry and Polymerase Chain Reaction

S. aureus and some species of coagulase-negative staphylococci, including S. chromogenes and S. simulans, commonly cause intramammary infections. However, little attention was paid to the antimicrobial resistance of these species with respect to their occurrence in dairy products, for example, popular sheep and goat cheeses made from unpasteurized milk. The aim of this study was to investigate such sheep and goat cheeses for the occurrence and antimicrobial resistance of the relevant staphylococci species. The staphylococcal isolates were identified by polymerase chain reaction (130 isolates) and matrix assisted laser desorption/ionization time-of-flight mass spectrometry. The most common species of S. aureus (56 isolates) were identified, as well as S. chromogenes (16 isolates) and S. simulans (10 isolates). Antimicrobial resistance to penicillin, oxacilin, ceftaroline, teicoplanin, gentamicin, erythromycin, tetracycline and ofloxacin was subsequently determined in these species using the agar dilution method. The highest resistance was confirmed in all species, especially to penicillin (91%) and erythromycin (67%). The highest sensitivity was confirmed to ofloxacin (83%). Due to the high incidence of penicillin and oxacilin-resistant staphylococci, the mecA gene was detected by polymerase chain reaction, which was confirmed only in S. aureus isolates (19%). Our study shows that the tested strains (77%) were resistant to more than one antibiotic at a time.

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Antimicrobial Stewardship Pharmacist Interventions for Coagulase-Negative Staphylococci Positive Blood Cultures Using Rapid Polymerase Chain Reaction

Annals of Pharmacotherapy ◽

10.1345/aph.1r439 ◽

2012 ◽

Vol 46 (11) ◽

pp. 1484-1490 ◽

Cited By ~ 44

Author(s):

Jordan R Wong ◽

Karri A Bauer ◽

Julie E Mangino ◽

Debra A Goff

Keyword(s):

Polymerase Chain Reaction ◽

Blood Culture ◽

Blood Cultures ◽

Hospital Length Of Stay ◽

Chain Reaction ◽

Coagulase Negative Staphylococci ◽

Pharmacist Interventions ◽

Rapid Polymerase Chain Reaction ◽

Polymerase Chain ◽

The Impact

BACKGROUND: No studies exist regarding the value of pharmacist interventions using rapid identification of coagulase-negative staphylococci (CoNS) by rapid polymerase chain reaction (rPCR) from blood cultures. OBJECTIVE: To evaluate the impact of interventions by infectious diseases pharmacists (ID PharmDs) on blood cultures positive for CoNS using rPCR and assess the duration of antistaphylococcal antibiotic therapy, hospital length of stay (LOS), and related costs. METHODS: A quasi-experimental, pre- and postintervention study of patients with positive blood cultures for CoNS, identified using rPCR, was conducted. Patients were included if there was a blood culture for CoNS from January 1, 2011, to March 31, 2011 (preintervention), or October 1, 2011, to January 18, 2012 (post-intervention). Exclusion criteria included age younger than 18 years or 89 years or older, neutropenia, incomplete records, and duplicate or mixed blood cultures. The setting was a 1200-bed academic medical center. The ID PharmD intervened on blood cultures identified in the postintervention group as CoNS after notification from the microbiology laboratory. The pre- and postintervention groups were compared to analyze the effect of the intervention. The primary outcome was time to discontinuation of antistaphylococcal antibiotics by the pharmacist intervention in patients with a positive blood culture for CoNS that was determined to be a contaminant. RESULTS: We analyzed 53 patients (31 preintervention, 22 postintervention) with CoNS blood culture contaminants. In the postintervention group, antistaphylococcal antibiotics were discontinued 32.0 hours sooner from time of rPCR result (median 57.7 vs 25.7 hours; p = 0.005), total antibiotic exposure decreased 43.5 hours (97.6 vs 54.1 hours; p = 0.011), infection-related LOS decreased 4.5 days (10 vs 5.5 days; p = 0.018), and infection-related costs decreased $8338 ($28,973 vs $20,635; p = 0.144). The pharmacist initiated vancomycin in 7 (21.9%) patients with CoNS bloodstream infections. CONCLUSIONS: Timely interventions by ID PharmDs using rPCR are required to impact the outcomes of patients with positive blood cultures for CoNS.

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Characterization of coagulase-negative staphylococci by primer-specific polymerase chain reaction and ribotyping

Clinical Microbiology and Infection ◽

10.1111/j.1469-0691.1998.tb00330.x ◽

1998 ◽

Vol 4 (1) ◽

pp. 27-32 ◽

Cited By ~ 4

Author(s):

Anna Gaszewska-Mastalarz ◽

Marzena Bartoszewicz-Potyrała ◽

Anna Przondo-Mordarska ◽

Marian Mordarski ◽

Jolanta Zakrzewska-Czerwińka

Keyword(s):

Polymerase Chain Reaction ◽

Chain Reaction ◽

Coagulase Negative Staphylococci ◽

Specific Polymerase Chain Reaction ◽

Polymerase Chain

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Determination of toxigenic capacity by reverse transcription polymerase chain reaction in coagulase-negative staphylococci and Staphylococcus aureus isolated from newborns in Brazil

Microbiology and Immunology ◽

10.1111/j.1348-0421.2011.00336.x ◽

2011 ◽

Vol 55 (6) ◽

pp. 394-407 ◽

Cited By ~ 7

Author(s):

Regina Adriana de Oliveira Calsolari ◽

Valéria Cataneli Pereira ◽

João Pessoa Araújo Júnior ◽

Maria de Lourdes Ribeiro de Souza da Cunha

Keyword(s):

Staphylococcus Aureus ◽

Polymerase Chain Reaction ◽

Reverse Transcription ◽

Chain Reaction ◽

Coagulase Negative Staphylococci ◽

Polymerase Chain ◽

And Staphylococcus Aureus

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Development and Validation of a Molecular Beacon Probe–Based Real-Time Polymerase Chain Reaction Assay for Rapid Detection of Methicillin Resistance in Staphylococcus aureus

Archives of Pathology & Laboratory Medicine ◽

10.5858/2003-127-845-davoam ◽

2003 ◽

Vol 127 (7) ◽

pp. 845-849 ◽

Cited By ~ 1

Author(s):

Sameer Elsayed ◽

Barbara L. Chow ◽

Nina L. Hamilton ◽

Daniel B. Gregson ◽

Johann D. D. Pitout ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Polymerase Chain Reaction ◽

Real Time ◽

Molecular Beacon ◽

Analytical Sensitivity ◽

Chain Reaction ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant ◽

Polymerase Chain ◽

Development And Validation

Abstract Context.—A rapid, real-time, duplex, fluorescent molecular beacon probe–based polymerase chain reaction (PCR) assay was recently developed for the detection of methicillin-resistant Staphylococcus aureus. Objective.—To describe the development and validation of this unique assay. Design.—Prospective laboratory analysis. Setting.—Urban health region/centralized diagnostic microbiology laboratory. Bacterial Strains.—One hundred eighty-one previously characterized clinical and American Type Culture Collection isolates, including 50 strains each of methicillin-resistant and methicillin-sensitive S aureus, plus 50 strains of coagulase-negative staphylococci and 31 nonstaphylococcal isolates to ensure assay specificity. Intervention.—Assays were performed on purified genomic DNA extracted from growing bacterial colonies. Two sets of oligonucleotide primers were used to specifically amplify the mecA and nuc genes, followed by detection of amplicons using fluorophore-labeled molecular beacon probes. Assays were performed on the Mx4000 Multiplex Quantitative PCR System (Stratagene Inc, La Jolla, Calif). Main Outcome Measures.—(1) Assay sensitivity and specificity, and (2) analytical sensitivity. Results.—The assay demonstrated 100% sensitivity and 100% specificity, and accurately characterized isolates as methicillin-resistant S aureus, methicillin-sensitive S aureus, or methicillin-resistant coagulase-negative staphylococci, with test results available in 2.5 hours. The analytical sensitivity of the assay was determined to be between 6 and 60 genomic equivalents. Conclusions.—This assay is rapid, accurate, easy to perform, and is compatible with other real-time PCR instruments, making it a suitable alternative to conventional PCR methodologies.

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Triplex real-time polymerase chain reaction assay for simultaneous detection of Staphylococcus aureus and coagulase-negative staphylococci and determination of methicillin resistance directly from positive blood culture bottles

Diagnostic Microbiology and Infectious Disease ◽

10.1016/j.diagmicrobio.2009.11.010 ◽

2010 ◽

Vol 66 (4) ◽

pp. 349-355 ◽

Cited By ~ 33

Author(s):

Abdullah Kilic ◽

Kenneth L. Muldrew ◽

Yi-Wei Tang ◽

A. Celal Basustaoglu

Keyword(s):

Staphylococcus Aureus ◽

Polymerase Chain Reaction ◽

Blood Culture ◽

Positive Blood Culture ◽

Methicillin Resistance ◽

Simultaneous Detection ◽

Chain Reaction ◽

Coagulase Negative Staphylococci ◽

Polymerase Chain

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Detection ofmecA, femA, andfemBgenes in clinical strains of staphylococci using polymerase chain reaction

Epidemiology and Infection ◽

10.1017/s0950268800051682 ◽

1994 ◽

Vol 113 (2) ◽

pp. 259-266 ◽

Cited By ~ 92

Author(s):

N. Kobayashi ◽

H. Wu ◽

K. Kojima ◽

K. Taniguchi ◽

S. Urasawa ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Methicillin Resistance ◽

Chain Reaction ◽

Coagulase Negative Staphylococci ◽

Base Pairs ◽

Pcr Product ◽

Resistant Strains ◽

Dna Fragment ◽

Polymerase Chain ◽

Almost All

SUMMARYMecA, a structural gene located on the chromosome ofStaphylococcus aureus, characterizes methicillin-resistantS. aureus(MRSA), andfemAandfemB(fem)genes encode proteins which influence the level of methicillin resistance ofS. aureus. In order to examine effectiveness of detectingmecAandfemgenes in identification of MRSA, the presence of these genes in 237 clinically isolated strains of staphylococci was investigated by polymerase chain reaction (PCR). An amplifiedmecADNA fragment of 533 base pairs (bp) was detected in 100% of oxacillin-resistantS. aureus, in 16·7 % of oxacillin-sensitiveS. aureus, in 81·5% ofS. epidermidis, and in 58·3% of other coagulase-negative staphylococci (CNS). While the PCR product offemA(509 bp) orfemB(651 bp) was obtained from almost all theS. aureusstrains except for five oxacillin-resistant strains (2·5%), neither of these genes were detected in CNS. Therefore, the detection offemAandfemBtogether withmecAby PCR was considered to be a more reliable indicator to identify MRSA by differentiating it frommecA-positive CNS than single detection ofmecA.

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Polymerase Chain Reaction Identification of Coagulase-Negative Staphylococci and of Strain Diversity and Spread of Staphylococcus epidermidis in a Major Medical Center in Lebanon

Infection Control and Hospital Epidemiology ◽

10.1086/505093 ◽

2006 ◽

Vol 27 (7) ◽

pp. 781-783 ◽

Cited By ~ 3

Author(s):

Inaya M. Abdallah ◽

George E Araj ◽

Ghassan M. Matar ◽

George Abdelnour ◽

Marwan Uwaydah ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Staphylococcus Epidermidis ◽

Rapd Analysis ◽

Medical Center ◽

Chain Reaction ◽

Coagulase Negative Staphylococci ◽

Strain Diversity ◽

Polymerase Chain ◽

Biochemical Testing ◽

Polymerase Chain Reaction Identification

A 2-step polymerase chain reaction (PCR) assay and random amplification of polymorphic DNA (RAPD) analysis, respectively, were assessed to identify coagulase-negative staphylococci organisms to the species level and to determine the strain diversity and spread of Staphylococcus epidermidis, the most frequently isolated species, in a medical center in Beirut, Lebanon. Our data indicated that PCR was faster and was more efficient in identifying S. epidermidis isolates than is conventional biochemical testing. RAPD analysis have shown that S. epidermidis strains were scattered across the different clinical services, demonstrating various clusters of infection in the medical center.

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