Mannitol Fermenting Methicillin-Resistant Coagulase Negative Staphylococci Isolated From Diabetic Foot Infections

Detection of mannitol fermenting coagulase-negative staphylococci is frequently unnoticed when Staphylococcus aureus is screening in the laboratory. On the other hand, the emergence of coagulase-negative staphylococci as critical human pathogens need dependable methods for the identification of clinically significant coagulase-negative staphylococci to understand the epidemiology of infections caused by these bacteria. The study aimed to identify mannitol fermenting coagulase-negative staphylococci that assumed to be Staphylococcus aureus as they formed yellow colonies on Mannitol Salt agar plates. Samples were taken from eighty-four patients with diabetic foot infections. The specimen was cultured on Blood agar and Mannitol Salt agar. Mannitol fermenting coagulase-negative staphylococci isolates diagnosed through Vitek2 system then confirmed by detecting 16S rRNA gene and absence of the nuc gene. Antibiotic sensitivity and methicillin resistance were detected by Vitek2 system, then methicillin resistance was confirmed by Oxacillin Salt Agar Screen test and detection of the mecA gene. Out of 81 Staphylococcus isolated from foot and nose of diabetic foot patients, twenty isolates were mannitol fermenting coagulase-negative staphylococci, they related to following species; Staphylococcus haemolyticus, staphylococcus lentus, Staphylococcus xylosus, Staphylococcus lugdunensis, Staphylococcus hominis, Staphylococcus galinarum and Staphylococcus saprophyticus). The majority of them (85%) were phenotypically methicillin-resistant and genotypically harbouring mecA gene. 80% were resistant to Erythromycin, 70% to Clindamycin, 35% to Trimethoprim-Sulphamethoxazole, 30% to Gentamicin and Rifampicin, 15% to Levofloxacin and Teicoplanin. 30% expressed inducible clindamycin resistance.

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Molecular detection and typing of methicillin-resistant Staphylococcus aureus and methicillin-resistant coagulase-negative staphylococci isolated from cattle, animal handlers, and their environment from Karnataka, Southern Province of India

Veterinary World ◽

10.14202/vetworld.2019.1760-1768 ◽

2019 ◽

Vol 12 (11) ◽

pp. 1760-1768 ◽

Cited By ~ 4

Author(s):

Nimita Venugopal ◽

Susweta Mitra ◽

Rituparna Tewari ◽

Feroze Ganaie ◽

Rajeswari Shome ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Animal Health ◽

Sccmec Type ◽

Meca Gene ◽

Molecular Characteristics ◽

Rrna Gene ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant

Background and Aim: Methicillin-resistant staphylococci are among the emerging pathogens which have become a threat to both human and animal health. The present investigation intended to examine the occurrence and the molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) recovered from cattle, its handlers, and their environment. Materials and Methods: A total of 666 specimens were subjected to culture method and genus-specific polymerase chain reaction (PCR) for the identification of Staphylococcus. Methicillin resistance was substantiated by PCR identification of mecA and mecC resistance determinants. Species-specific identification of mecA positive isolates was conducted by multiplex PCR. The unidentified species were deciphered by 16S rRNA gene sequencing approach. The mecA positive isolates were further characterized by staphylococcal cassette chromosome mec (SCCmec) typing and multilocus sequence typing (MLST). Results: Duplex PCR identified 728 Staphylococcus isolates, of which 66 (9%) were positive for mecA gene. MRSA constituted 24% of the total mecA positive isolates. Among MRCoNS, Staphylococcus epidermidis (42%), and Staphylococcus haemolyticus (11%) were the most common species identified. Overall, 47% of the mecA positive isolates belonged to SCCmec type V. MLST analysis showed eight different sequence types (STs) among MRSA isolates of which five were novel STs. Among methicillin-resistant S. epidermidis, 19 different STs were found, of which nine novel STs were detected. Conclusion: The increase in the prevalence of mecA positive staphylococci, especially MRCoNS in cattle is a great concern in view of their transmission potential. Hence, continuous monitoring and molecular characterization of methicillin-resistant staphylococci should be elucidated in human and animal sectors so as to prevent the spread of these resistant pathogens.

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Panton Valentine Gene in both Community-acquired and Healthcare-acquired Methicillin Resistant Staphylococcus aureus Isolates from Ain Shams University Hospitals

QJM ◽

10.1093/qjmed/hcaa053 ◽

2020 ◽

Vol 113 (Supplement_1) ◽

Author(s):

R A Mohamed ◽

L F Fathi ◽

N N Salaheldeen

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Cross Sectional Study ◽

P Value ◽

University Hospitals ◽

Cross Sectional ◽

Mannitol Salt Agar ◽

Methicillin Resistant

Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA) is a major pathogen that is associated with both hospital and community infections. Panton Valentine leukocidin (PVL) is an important virulence factor of S. aureus that is considered by many authors a marker of community acquired MRSA (CA-MRSA). Aim of the Work This study aimed to determine the prevalence of PVL genes among healthcare acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) and CA-MRSA isolates, and to test the hypothesis that PVL is a reliable marker of CA-MRSA isolates. Material and Methods This comparative cross-sectional study was done on fifteen community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) and fifteen hospital acquired methicillin resistant Staphylococcus aureus (HA-MRSA), obtained from patients attending outpatient clinics, presenting with community-acquired pyogenic infections and patients with healthcare acquired pyogenic infections in Intensive Care Units (ICUs), during the period from May 2017 till February 2018. Clinical specimens included pus and different body fluids. Staphylococcus aureus was isolated and identified using conventional microbiological methods3. Isolates were then tested for methicillin resistance by culture on mannitol salt agar (MSA) with cefoxitin4. The presence of mecA and pvl genes in all MRSA isolates was subsequently detected by PCR5,6. Results Among 15 HA-MRSA isolates, mecA gene was positive in 40% (6/15) of isolates, while pvl gene was positive in 53.3% (8/15) of isolates. Among 15 CA-MRSA isolates, mecA gene was positive in 46.7% (7/15) of isolates, while pvl gene was positive in 26.7% (4/15) of isolates. Conclusion We conclude that pvl gene is not a sole genetic marker for diagnosis CA-MRSA, as there was no significant correlation between mecA that encodes for methicillin resistance and pvl genes among fifteen CA-MRSA isolates (P value =1).

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Occurrence and characteristics of methicillin resistant Staphylococcus aureus and methicillin resistant coagulase-negative staphylococci in raw milk manufacturing

Czech Journal of Food Sciences ◽

10.17221/4443-cjfs ◽

2012 ◽

Vol 29 (Special Issue) ◽

pp. S11-S16 ◽

Cited By ~ 11

Author(s):

M. Vyletělová ◽

H. Vlková ◽

I. Manga

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Diffusion Method ◽

Biochemical Tests ◽

Coagulase Negative Staphylococci ◽

Disk Diffusion Method ◽

Methicillin Resistant ◽

Staphylococcal Cassette Chromosome

For monitoring the occurrence of MRSA (methicillin resistant Staphylococcus aureus) and MR-CNS (methicillin resistant coagulase-negative staphylococci), cow’s, goat’s, and sheep’s milks (bulk milks and individual samples) were investigated. Human nasal and throat swabs of the farm staff and nasal swabs of animals were also investigated as well. In total 1729 samples were examined and 634 strains were isolated by means of the cultivation method and used in this study. Generic identification of the staphylococci isolates was done performed by biochemical tests and all S. aureus and CNS isolates were checked by the PCR method for the presence of mecA gene which is responsible for methicillin resistance. The presence of the staphylococcal cassette chromosome mec (SCCmec), Panton-Valentine leukocidin (pvl) and genes encoding toxic shock syndrome toxin (tst) was detected in all strains confirmed as MRSA. The species were also examined for antimicrobial susceptibility by using disk diffusion method with antibiotic disks. S. aureus was the most frequently identified species from the samples tested (n = 557; 32.2%), followed by S. haemolyticus (n = 32; 1.9%), S. chromogenes (n = 24; 1.4%), S. epidermidis (n = 20; 1.2%), and S. caprae (n = 1; 0.16%). Among the resistant staphylococci (n = 49), S. aureus (n = 25; 51%) was found the most frequently, followed by S. epidermidis (n = 17; 34.7%), S. chromogenes (n = 6; 12.2%), and S. haemolyticus (n = 1; 2%). The resistant Staphyloccocus sp. occurred mainly in cow’s milk (MRSA, S. epidermidis, S. chromogenes, S. haemolyticus) and in animal’s swabs (S. epidermidis). One MRSA was also found in goat’s milk and one was isolated from human swab. No resistant strains were found in sheep’s milk. The negative results of the analysed genes presence (pvl, tst) were identical with all MRSA tested. The staphylococcal cassette chromosome mec (SCCmec) was classified as type IV or V.

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Methicillin-Resistant Staphylococcus aureus (MRSA) Infection of Diabetic Foot Ulcers at a Tertiary Care Hospital in Accra, Ghana

Pathogens ◽

10.3390/pathogens10080937 ◽

2021 ◽

Vol 10 (8) ◽

pp. 937

Author(s):

Ramzy B. Anafo ◽

Yacoba Atiase ◽

Nicholas T. K. D. Dayie ◽

Fleischer C. N. Kotey ◽

Patience B. Tetteh-Quarcoo ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Multidrug Resistance ◽

Teaching Hospital ◽

Diabetic Foot ◽

Foot Ulcer ◽

Foot Ulcers ◽

Diabetic Foot Ulcers ◽

Coagulase Negative Staphylococci ◽

Methicillin Resistant ◽

Mrsa Infection

Aim: This study investigated the spectrum of bacteria infecting the ulcers of individuals with diabetes at the Korle Bu Teaching Hospital in Accra, Ghana, focusing on Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA), with respect to their prevalence, factors predisposing to their infection of the ulcers, and antimicrobial resistance patterns. Methodology: This cross-sectional study was conducted at The Ulcer Clinic, Department of Surgery, Korle Bu Teaching Hospital, involving 100 diabetic foot ulcer patients. The ulcer of each study participant was swabbed and cultured bacteriologically, following standard procedures. Antimicrobial susceptibility testing was done for all S. aureus isolated, using the Kirby-Bauer method. Results: In total, 96% of the participants had their ulcers infected—32.3% (n = 31) of these had their ulcers infected with one bacterium, 47.9% (n = 46) with two bacteria, 18.8% (n = 18) with three bacteria, and 1.0% (n = 1) with four bacteria. The prevalence of S. aureus and MRSA were 19% and 6%, respectively. The distribution of the other bacteria was as follows: coagulase-negative Staphylococci (CoNS) (54%), Escherichia coli (24%), Pseudomonas spp. (19%), Citrobacter koseri and Morganella morgana (12% each), Klebsiella oxytoca (11%), Proteus vulgaris (8%), Enterococcus spp. (6%), Klebsiella pneumoniae (5%), Proteus mirabilis and Enterobacter spp. (4%), Klebsiella spp. (2%), and Streptococcus spp. (1%). The resistance rates of S. aureus decreased across penicillin (100%, n = 19), tetracycline (47.4%, n = 9), cotrimoxazole (42.1%, n = 8), cefoxitin (31.6%, n = 6), erythromycin and clindamycin (26.3% each, n = 5), norfloxacin and gentamicin (15.8% each, n = 3), rifampicin (10.5%, n = 2), linezolid (5.3%, n = 1), and fusidic acid (0.0%, n = 0). The proportion of multidrug resistance was 47.4% (n = 9). Except for foot ulcer infection with coagulase-negative Staphylococci, which was protective of S. aureus infection of the ulcers (OR = 0.029, p = 0.001, 95% CI = 0.004–0.231), no predictor of S. aureus, MRSA, or polymicrobial ulcer infection was identified. Conclusions: The prevalence of S. aureus and MRSA infection of the diabetic foot ulcers were high, but lower than those of the predominant infector, coagulase-negative Staphylococci and the next highest infecting agent, E. coli. Diabetic foot ulcers’ infection with coagulase-negative Staphylococci protected against their infection with S. aureus. The prevalence of multidrug resistance was high, highlighting the need to further intensify antimicrobial stewardship programmes.

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Detection of mecA gene by latex agglutination and its molecular analysis by PCR in methicillin resistant staphylococcus aureus.

The Professional Medical Journal ◽

10.29309/tpmj/2020.27.07.3752 ◽

2020 ◽

Vol 27 (07) ◽

pp. 1363-1370

Author(s):

Aneela Khawaja ◽

Iffat Javed ◽

Sohaila Mushtaq ◽

Saeed Anwar ◽

Faiqa Arshad ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Latex Agglutination ◽

Medical Institute ◽

Cross Sectional ◽

Methicillin Resistant ◽

Agglutination Method ◽

Resistant Strains

Antimicrobial resistance (AMR) is a devastating question that is threatening the health globally. The extensive and indiscriminative use of antibiotics has evolved a notorious resistance in Staphylococcus aureus. This resistance developed through possession of mecA gene, which codes for modified penicillin binding protein (PBP2a) and the emergent strain being labeled “methicillin resistant Staphylococcus aureus”. Conventional phenotypic techniques for detection of MRSA rely on standardization of cultural characteristics. The drawbacks of diagnostic error to report MRSA include: poor prognosis, expensive treatment, dissemination of multi-drug resistant strains and even treatment failure. Latex agglutination method can be adopted as a more accurate and quick strategy for rapid detection of methicillin resistance. Objectives: To compare detection of mecA gene in methicillin resistant isolates of Staphylococcus aureus by latex agglutination and PCR; by assessing the sensitivity and specificity of both methods. Study Design: Descriptive Cross-Sectional study. Setting: Pathology Department, Post Graduate Medical Institute, Lahore. Period: From January 2015 to December 2015; according to standard operating procedures at Microbiology laboratory. Material & Methods: A total 713 consecutive, non-duplicate isolates of Staphylococcus aureus were processed. Methicillin resistance was determined using cefoxitin (30mg) by Kirby-Bauer method using CLSI guideline (2016), latex agglutination method; and PCR for mecA gene. Results: The results showed that out of 713 Staphylococcus aureus isolates, 92 (12.90%) isolates were resistant to cefoxitin and were labelled as MRSA. majority MRSA isolates recovered from pus (44.57%) and wound swab (20.65%), followed by blood (13.04%), fluid (8.70%), CSF (4.35%), CVP (3.26%), HVS (3.26%) and tracheal secretion (2.17%). By latex agglutination method, 87 (94.50%) were positive for PBP2a; while on PCR mecA gene was detected only in 82 (89.10%) MRSA isolates. When assessed with PCR (gold standard) the sensitivity and diagnostic accuracy of latex agglutination was 100% and 94.57%, respectively. Conclusion: Latex agglutination test can be employed as rapid and reliable diagnostic technique in MRSA isolates for mecA gene detection, where resources for molecular methods are inadequate. This can effectually lessen the misdiagnosis of resistant strains, and over/ ill-use of antibiotics.

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Diabetic Foot Infections: Local Prevalence of and Case–Control Study of Risk Factors for Methicillin-Resistant Staphylococcus aureus and Pseudomonas aeruginosa

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa412 ◽

2020 ◽

Vol 7 (10) ◽

Author(s):

Justin J Kim ◽

Alison Lydecker ◽

Rohini Davé ◽

Jacqueline T Bork ◽

Mary-Claire Roghmann

Keyword(s):

Risk Factors ◽

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Diabetic Foot ◽

Methicillin Resistant Staphylococcus Aureus ◽

Case Control Study ◽

Case Control ◽

Methicillin Resistant ◽

Diabetic Foot Infections ◽

Control Study

Abstract We identified deep diabetic foot infections by culture and conducted a case–control study examining the risk factors for moderate to severe methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PsA) diabetic foot infections. Our MRSA prevalence was lower than literature values; PsA was higher. Gangrene may be predictive of Pseudomonas infection.

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Daptomycin for Methicillin-Resistant Staphylococcus aureus Diabetic Foot Infections

Journal of the American Podiatric Medical Association ◽

10.7547/0003-0538-104.2.159 ◽

2014 ◽

Vol 104 (2) ◽

pp. 159-168 ◽

Cited By ~ 3

Author(s):

Warren S. Joseph ◽

Thomas Quast ◽

Alberto Cogo ◽

Monica G. Crompton ◽

Min Jung Yoon ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Diabetic Foot ◽

Methicillin Resistant Staphylococcus Aureus ◽

Clinical Success ◽

Initial Therapy ◽

Antibiotic Agent ◽

Negative Effects ◽

Methicillin Resistant ◽

Diabetic Foot Infections ◽

Antibiotic Drug

Background Diabetic foot infection (DFI) is a serious, difficult-to-treat infection, especially when caused by methicillin-resistant Staphylococcus aureus (MRSA). Vancomycin has been the standard treatment for MRSA infection, but lower response rates in MRSA skin infections have been reported. This analysis assessed the outcome and safety of daptomycin therapy in patients with a DFI caused by MRSA. Methods Using the Cubicin Outcomes Registry and Experience and the European Cubicin Outcomes Registry and Experience (2006–2009), 79 patients with MRSA DFI were identified and included in this analysis. Results In the 74 evaluable patients, daptomycin was administered at a median dose of 4.8 mg/kg primarily every 24 hours (85.1%) and for a median of 15.0 days. Overall, 77.0% of the patients (57 of 74) received initial therapy with activity against MRSA; however, of patients receiving daptomycin as second-line therapy (n = 31), only 45.2% were treated with an antibiotic agent active against MRSA. The overall clinical success and treatment failure rates were 89.2% and 10.8%, respectively. Success with daptomycin therapy was higher in patients who had surgery and in those whose initial therapy was daptomycin. Eleven patients had 14 adverse events, two of which were possibly related to daptomycin use and led to discontinuation. Conclusions In a large real-world cohort of patients with MRSA DFI, daptomycin therapy was shown to be generally well tolerated and effective. The use of an anti-MRSA antibiotic agent should be considered when implementing first-line antibiotic drug therapy for DFI in countries where MRSA is common to avoid inappropriate empirical treatment and potential negative effects on outcomes.

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Correlation Between Patients With Methicillin-Resistant Staphylococcus aureus (MRSA) Nares Colonization and MRSA Diabetic Foot Infections

The International Journal of Lower Extremity Wounds ◽

10.1177/1534734620963570 ◽

2020 ◽

pp. 153473462096357

Author(s):

Jacquelyn Brondo ◽

Kathleen Morneau ◽

Teri Hopkins ◽

Linda Yang ◽

Jose Cadena-Zuluaga ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Diabetic Foot ◽

Predictive Value ◽

Methicillin Resistant Staphylococcus Aureus ◽

Empiric Therapy ◽

Inclusion Criteria ◽

Methicillin Resistant ◽

Diabetic Foot Infections ◽

Prior Literature ◽

Mrsa Infection

Infectious Diseases Society of America diabetic foot infection (DFI) guidelines indicate empiric methicillin-resistant Staphylococcus aureus (MRSA) coverage for patients with a history of MRSA infection, when local prevalence of MRSA is high, or infection is clinically severe. These recommendations may lead to overutilization of empiric MRSA coverage, which can result in serious consequences. A strong negative predictive value (NPV) has been reported in literature for pneumonia, and recently, for all anatomical sites of infection. While these findings are promising, further validation is needed before clinicians may confidently use MRSA nares to guide empiric therapy for DFIs. A retrospective electronic medical record review was completed between October 1, 2013 and October 1, 2019. Patients met inclusion criteria if they were at least 18, admitted with a DFI, had MRSA nares test results, and DFI cultures. Patients were excluded if pregnant or MRSA infection within 1 year prior to index admission for DFI. A total of 200 patients met inclusion criteria. The majority of study participants were male with a mean age of 63. NPV of MRSA nares for MRSA DFIs was determined to be 94% and positive predictive value 58%. Sensitivity and specificity were 56% and 94%, respectively. Results of this study are consistent with prior literature supporting strong correlation of NPV for MRSA nares. The DFIs evaluated suggest a strong NPV of MRSA nares for MRSA DFIs, which may allow for faster de-escalation of empiric anti-MRSA antibiotic therapy and lower risk of adverse events associated with anti-MRSA therapy.

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Utility of Methicillin-Resistant Staphylococcus aureus Nares Screening for Patients with a Diabetic Foot Infection

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02213-19 ◽

2020 ◽

Vol 64 (4) ◽

Cited By ~ 3

Author(s):

Kari A. Mergenhagen ◽

Michael Croix ◽

Kaitlyn E. Starr ◽

John A. Sellick ◽

Alan J. Lesse

Keyword(s):

Staphylococcus Aureus ◽

Diabetic Foot ◽

International Classification Of Diseases ◽

Methicillin Resistant ◽

Content Type ◽

Diabetic Foot Infection ◽

Entire Cohort ◽

Diabetic Foot Infections ◽

Medical Centers ◽

Classification Of Diseases

ABSTRACT Treatment of suspected methicillin-resistant Staphylococcus aureus (MRSA) is a cornerstone of severe diabetic foot infections; however, antibiotics can be associated with toxicity. The objective of this study was to determine the negative predictive value (NPV) of MRSA nares screening in the determination of subsequent MRSA in patients with a diabetic foot infection. This was a retrospective cohort study across Veterans Affairs (VA) medical centers from 1 January 2007 to 1 January 2018. Data from patients with an International Classification of Diseases (ICD) code for a diabetic foot infection with MRSA nares screening, and subsequent cultures were evaluated for the presence of MRSA. NPVs were calculated for the entire cohort, as well as for a subgroup representing deep cultures. Additionally, the distribution of all pathogens isolated from diabetic foot infections was determined. A total of 8,163 episodes were included in the analysis for NPV. The NPV of MRSA nares screening for MRSA diabetic foot infection was 89.6%. For the deep cultures, the NPV was 89.2%. The NPV for cultures originating from the foot was 89.7%, and the NPV for those originating from the toe was 89.4%. There were 17,822 pathogens isolated from the diabetic foot cultures. MRSA was isolated in 7.5% of cultures, and methicillin-susceptible S. aureus was isolated in 24.8%. Enterococcus was identified in 14.7% of cultures, Proteus in 7.3%, and Pseudomonas in 6.8% of cultures. Given the high NPVs, the use of MRSA nares screening may be appropriate as a stewardship tool for deescalation and avoidance of empirical anti-MRSA therapy in patients who are not nasal carries of MRSA.

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