scholarly journals Predominance of PVL-negative community-associated methicillin-resistant Staphylococcus aureus sequence type 8 in newly diagnosed HIV-infected adults, Tanzania

2021 ◽  
Author(s):  
Joel Manyahi ◽  
Sabrina J. Moyo ◽  
Said Aboud ◽  
Nina Langeland ◽  
Bjørn Blomberg
Keyword(s):  
Staphylococcus Aureus ◽  
Hiv Infection ◽  
Diffusion Method ◽  
Molecular Characteristics ◽  
People Living With Hiv ◽  
Newly Diagnosed ◽  
Beta Lactam ◽  
Disk Diffusion Method ◽  
Methicillin Resistant ◽  
Inducible Clindamycin Resistance

AbstractDifficult-to-treat infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are of concern in people living with HIV infection as they are more vulnerable to infection. We aimed to identify molecular characteristics of MRSA colonizing newly diagnosed HIV-infected adults in Tanzania. Individuals newly diagnosed with HIV infection were recruited in Dar es Salaam, Tanzania, from April 2017 to May 2018, as part of the randomized clinical trial CoTrimResist (ClinicalTrials.gov identifier: NCT03087890). Nasal/nasopharyngeal isolates of Staphylococcus aureus were susceptibility tested by disk diffusion method, and cefoxitin-resistant isolates were characterized by short-reads whole genome sequencing. Four percent (22/537) of patients carried MRSA in the nose/nasopharynx. MRSA isolates were frequently resistant towards gentamicin (95%), ciprofloxacin (91%), and erythromycin (82%) but less often towards trimethoprim-sulfamethoxazole (9%). Seventy-three percent had inducible clindamycin resistance. Erythromycin-resistant isolates harbored ermC (15/18) and LmrS (3/18) resistance genes. Ciprofloxacin resistance was mediated by mutations of the quinolone resistance-determining region (QRDR) sequence in the gyrA (S84L) and parC (S80Y) genes. All isolates belonged to the CC8 and ST8-SCCmecIV MRSA clone. Ninety-five percent of the MRSA isolates were spa-type t1476, and one exhibited spa-type t064. All isolates were negative for Panton-Valentine leucocidin (PVL) and arginine catabolic mobile element (ACME) type 1. All ST8-SCCmecIV-spa-t1476 MRSA clones from Tanzania were unrelated to the globally successful USA300 clone. Carriage of ST8 MRSA (non-USA300) was common among newly diagnosed HIV-infected adults in Tanzania. Frequent co-resistance to non-beta lactam antibiotics limits therapeutic options when infection occurs.

scholarly journals Molecular investigation of methicillin-resistant staphylococcus aureus isolates from blood: USA600 emerges as the major type

2018 ◽  
Vol 12 (05) ◽  
pp. 336-341 ◽  
Author(s):  
Mehdi Goudarzi ◽  
Fattaneh Sabzehali ◽  
Mohsen Heidary ◽  
Hadi Azimi ◽  
Hossein Goudarzi
Keyword(s):  
Staphylococcus Aureus ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Meca Gene ◽  
Diffusion Method ◽  
Major Type ◽  
Molecular Characteristics ◽  
Disk Diffusion Method ◽  
Cross Sectional ◽  
Methicillin Resistant ◽  
Encoding Genes

Introduction: The widespread emergence of methicillin-resistant Staphylococcus aureus is turning into a real worry in public health. The goals of the present study were to identify resistance and virulence encoding genes and molecular characteristics of methicillin-resistant S. aureus bloodstream isolates. Methodology: A cross-sectional study was conducted on 84 S. aureus bloodstream isolates during a 10-month period. To evaluate antibiotic susceptibility of the isolates, we used Kirby-Bauer disk diffusion method. In addition, the prevalence of antimicrobial resistance and toxins genes was assessed using polymerase chain reaction. Isolates were typed according to polymorphisms seven housekeeping genes by MLST. Results: All the isolates were resistant to methicillin. The most prevalent resistance gene was mecA gene (100%) followed by tetM (57.1%), aac (6΄)-Ie/aph (2˝) (53.6%), ant (4΄)-Ia (46.4%), ermA (45.2%), msrA (35.7%), msrB (33.3%), aph (3΄)-IIIa (33.3%), ermB (31%), ermC (16.7%), and mupA (14.3%) genes. The presence of toxin encoding genes tst, pvl, eta, and etb were detected in 25%, 14.3%, 3.6% and 3.6%, respectively. The isolates were classified into five different sequence types: ST45 (29.8%), ST239 (27.4%), ST858 (21.4%), ST22 (17.8%), and ST59 (3.6%). All the high-level mupirocin-resistant (HLMUPR) strains belonged to ST239, while the low-level mupirocin resistant (LLMUPR) strains belonged to ST22 (13%) and ST239 (6%). Conclusions: To the best of our knowledge, the present study is the first report of ST59 in MRSA bloodstream isolates in Iran. Our data demonstrated the need for thorough epidemiological monitoring to detect emergence and dissemination of MDR- MRSA types in our hospitals.

scholarly journals Methicillin and Inducible Clindamycin-resistant Staphylococcus aureus Isolates from Clinical Samples in Abia State

2019 ◽  
pp. 1-9
Author(s):  
A. C. Ifediora ◽  
R. N. Nwabueze ◽  
E. S. Amadi ◽  
C. I. Chikwendu
Keyword(s):  
Staphylococcus Aureus ◽  
Bacterial Pathogen ◽  
Resistance Rate ◽  
Diffusion Method ◽  
Multi Drug Resistance ◽  
Clinical Samples ◽  
P Value ◽  
Disk Diffusion Method ◽  
Methicillin Resistant ◽  
Inducible Clindamycin Resistance

Staphylococcus aureus is a major bacterial pathogen that causes different community and hospital-acquired infections. S. aureus resistant to methicillin has become a big and expanding problem of concern in many developing countries. Clindamycin has also been discovered to be a preferred therapeutic alternative for the treatment of both methicillin susceptible and resistant staphylococcal infections. This study examined the prevalence of Methicillin-resistant Staphylococcus aureus (MRSA) in clinical samples of patients in Abia state, Nigeria using standard recommended procedures. A total of 750 clinical specimens of blood and urine samples, wound, ear, nasal, high vaginal and ear swabs were collected from three major health facilities in Abia state, Nigeria. Each sample was cultured for bacterial isolates and examined for colonial and cellular morphology while biochemical identification was performed. Antimicrobial susceptibility test was performed on Mueller-Hinton agar (MHA) by disc diffusion method and MRSA screening was done using cefoxitin disc.  A total of 265 (35.3%) S. aureus isolates were recovered, out of which 126(47.5%) were from males and 139(52.5%) were from females, however there was no association between the prevalence and gender (p-value = 0.05) and also prevalence and age (p-value = 0.52). Of the 265 S. aureus isolates recovered, 164(61.9%) were MRSA. All 100% of the MRSA were susceptible to vancomycin, 120(73.2%) to clindamycin, 92(56.1%) to gentamycin. All 100% were resistant to ceftazidine, 157(95.7%) to cloxacillin, 146(89.0%) to augmentin, 136(82.9%) to ceftriaxone and 103(61.6%) to erythromycin. The MRSA strains showed much higher resistance rate than their MSSA counterparts to all tested antibiotic except clindamycin. 64(39.0%) of the MRSA were resistant to 4 classes of antibiotics indicating multi drug resistance (MDR). The overall prevalence of inducible clindamycin resistance among methicillin resistant isolates was 29(17.7%). This implies that 17.7% could have been misidentified as clindamycin susceptible by Kirby-Bauer disk diffusion method. In conclusion prevalence of MRSA was high and it is important to routinely carry out the D-test for detection of inducible clindamycin resistance if clindamycin is considered as a treatment option.

scholarly journals Methicillin-resistant Staphylococcus aureus bloodstream infection: risk factors and clinical outcome in non-intensive-care units

2012 ◽  
Vol 45 (2) ◽  
pp. 189-193 ◽  
Author(s):  
Karinne Spirandelli Carvalho Naves ◽  
Natália Vaz da Trindade ◽  
Paulo Pinto Gontijo Filho
Keyword(s):  
Risk Factors ◽  
Staphylococcus Aureus ◽  
Bloodstream Infection ◽  
Antimicrobial Agents ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Methicillin Resistance ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Methicillin Resistant ◽  
Staphylococcus Aureus Bloodstream Infection

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is spread out in hospitals across different regions of the world and is regarded as the major agent of nosocomial infections, causing infections such as skin and soft tissue pneumonia and sepsis. The aim of this study was to identify risk factors for methicillin-resistance in Staphylococcus aureus bloodstream infection (BSI) and the predictive factors for death. METHODS: A retrospective cohort of fifty-one patients presenting bacteraemia due to S. aureus between September 2006 and September 2008 was analysed. Staphylococcu aureus samples were obtained from blood cultures performed by clinical hospital microbiology laboratory from the Uberlândia Federal University. Methicillinresistance was determined by growth on oxacillin screen agar and antimicrobial susceptibility by means of the disk diffusion method. RESULTS: We found similar numbers of MRSA (56.8%) and methicillin-susceptible Staphylococcus aureus (MSSA) (43.2%) infections, and the overall hospital mortality ratio was 47%, predominantly in MRSA group (70.8% vs. 29.2%) (p=0.05). Age (p=0.02) was significantly higher in MRSA patients as also was the use of central venous catheter (p=0.02). The use of two or more antimicrobial agents (p=0.03) and the length of hospital stay prior to bacteraemia superior to seven days (p=0.006) were associated with mortality. High odds ratio value was observed in cardiopathy as comorbidity. CONCLUSIONS: Despite several risk factors associated with MRSA and MSSA infection, the use of two or more antimicrobial agents was the unique independent variable associated with mortality.

Evaluation of antibiotic resistance pattern and mecA gene frequency in methicillin-resistant Staphylococcus aureus strains collected from clinical specimens in Marand hospital and treatment centers, Iran

2021 ◽  
Author(s):  
Abolfazl Jafari-Sales ◽  
Zahra Sadeghi Deylamdeh ◽  
Afsoon Shariat
Keyword(s):  
Staphylococcus Aureus ◽  
Antibiotic Resistance ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Meca Gene ◽  
Disk Diffusion ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Methicillin Resistant ◽  
Medical Centers ◽  
Wide Range

Introduction: Staphylococcus aureus causes a wide range of infections and as a multivalent pathogen is one of the causative agents of nosocomial and community infections. Therefore, the aim of this study was to identify and determine the pattern of antibiotic resistance of methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients in hospitals and medical centers in Marand city and also to evaluate the presence of mecA gene. Materials and Methods: In this cross-sectional descriptive study, 385 samples of S. aureus were collected from different clinical samples of patients in hospitals and medical centers of Marand city. S. aureus was identified using standard biochemical methods.  Methicillin resistance was determined by disk diffusion method in the presence of oxacillin and cefoxitin. The pattern of antibiotic resistance of the strains was determined by disk diffusion method and according to CLSI recommendation and also PCR method was used to evaluate the frequency of MecA gene. Results: In the present study, out of 385 samples of S. aureus, 215 (55.84%) samples were methicillin resistant. PCR results for mecA gene showed that 110 samples had mecA gene.  The highest antibiotic resistance was observed against penicillin (100%) and erythromycin (83.63%). Most MRSA were isolated from urine and wound samples. Conclusion: The results of this study indicate the prevalence of methicillin-resistant species and also the increase in antibiotic resistance of MRSA to various antibiotics.  Therefore, in order to prevent increased resistance to other antibiotics, it is recommended to avoid inappropriate use of antibiotics.

Assessment of Mupirocin Resistance among Clinical Isolates of Methicillin Resistant Staphylococcus aureus

2021 ◽  
Vol 30 (1) ◽  
pp. 109-114
Author(s):  
Nancy M. Attia ◽  
Abeer Abd El Rahim Ghazal ◽  
Omnia M. Khaleel ◽  
Ahmed Gaballah
Keyword(s):  
Staphylococcus Aureus ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Methicillin Resistant ◽  
Mupirocin Resistance ◽  
High Level ◽  
Research Institute Hospital ◽  
Low Prevalence ◽  
Mrsa Colonization

Background: Methicillin-resistant Staphylococcus aureus (MRSA) colonization is considered a major risk factor for nosocomial infections and its decolonization has reduced these infections. Mupirocin (MUP) is the topical antibiotic of choice for decolonization. MUP decolonization failure is attributed to MUP resistance. Objective: The aim of the current study is to assess MUP resistance among MRSA isolates phenotypically and genotypically. Methodology: Fifty MRSA isolates were identified in Microbiology Department in the Medical Research Institute hospital, Alexandria University. Antibiotic susceptibility to different classes of antibiotics by disk diffusion method was done. MUP minimum inhibitory concentration (MIC) was determined phenotypically by MUP Ezy MIC™ Strips. MUP resistance was determined genetically by multiplex PCR detection of mupA and mupB. Results: Of all MRSA isolates, 6% exhibited high level and none showed low level MUP resistance. Only mupA was detected in all resistant isolates. Conclusion: Despite low prevalence of MUP resistance, it is appropriate to test MUP resistance prior nasal decolonization

Molecular Characterization, Virulence Determinants, and Antimicrobial Resistance Profile of Methicillin-Resistant Staphylococcus aureus in the North of Iran; a High Prevalence of ST239-SCCmec III/t037 Clone

Chemotherapy ◽  
2021 ◽  
pp. 1-10
Author(s):  
Hao Ying ◽  
Trias Mahmudiono ◽  
Tawfeeq Alghazali ◽  
Walid Kamal Abdelbasset ◽  
Parand Khadivar ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Health Concern ◽  
Diffusion Method ◽  
Virulence Determinants ◽  
Disk Diffusion Method ◽  
Methicillin Resistant ◽  
The North ◽  
Effective Manner ◽  
High Prevalence ◽  
North Of Iran

<b><i>Objectives:</i></b> Emergence and prevalence of methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) have become a major universal health concern, limiting therapeutic options. <b><i>Methods:</i></b> A total number of 37 MRSA isolates, including 19 clinical isolates from hospitalized patients and 18 colonizing isolates from health care workers were identified from 3 hospitals, in Gorgan, North of Iran. Antimicrobial susceptibility test was performed using the disk diffusion method and E-test. The presence of virulence and antibiotic resistance determinants were evaluated by PCR. The genotypical characterization was further analyzed using multi-locus sequence, <i>spa</i>, staphylococcal cassette chromosome, <i>mec</i> (SCC<i>mec)</i>, and <i>agr</i> typing. <b><i>Results:</i></b> The frequency of MRSA among <i>S. aureus</i> isolates was 38.14% (37/97). The most frequent <i>S. aureus</i> resistant isolates were found to be obstinate against penicillin (98%) and gentamicin (82.5%). Additionally, the lowest resistance rates were found against daptomycin (0%), vancomycin (2.7%), and quinupristin-dalfopristin (5.4%). All MRSA isolates were susceptible to daptomycin with minimum inhibitory concentration (MIC)50/MIC90 of 0.25/0.5 μg/mL. One isolate belonging to sequence type 239 (ST239)-SCC<i>mec</i>III/t037 clone (MIC ≥16 μg/mL) was resistant to vancomycin. All but 1 isolate that shares ST22-SCC<i>mec</i> IV/t790 strain were positive for both <i>tsst</i> and <i>pvl</i> genes. The most predominant MRSA isolates (27%) were associated with ST239-SCC<i>mec</i> III/t037, and ST239-SCC<i>mec</i> III/t924 (16.2%) clones, subsequently. In our study, circulating MRSA strains were genetically diverse with a high prevalence of ST239-SCC<i>mec</i> III/t037 clone. <b><i>Conclusion:</i></b> These findings emphasize the need for future and continuous surveillance studies on MRSA to prevent the dissemination of existing multidrug resistance MRSA clones in an effective manner.

scholarly journals Antimicrobial Activity of Cultivable Endophytic and Rhizosphere Fungi Associated with “Mile-a-Minute,” Mikania cordata (Asteraceae)

2020 ◽  
Vol 2020 ◽  
pp. 1-7 ◽  
Author(s):  
Pavithra L. Jayatilake ◽  
Helani Munasinghe
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Antimicrobial Properties ◽  
Pharmaceutical Products ◽  
Diffusion Method ◽  
Molecular Characteristics ◽  
Disk Diffusion Method ◽  
Rhizosphere Fungi

Endophytic and rhizosphere fungi are understood to be aiding the host plant to overcome a range of biotic and abiotic stresses (nutrition depletion, droughts, etc.) hence, they remain to be reservoirs of plethora of natural products with immense use. Consequently, this investigation of endophytic and rhizosphere fungi isolated from Mikania cordata (a perennial vine that is well established in Sri Lanka) for their antimicrobial properties was performed with the aim of future derivation of potential beneficial pharmaceutical products. Leaves, twigs, and roots of M. cordata were utilized to isolate a total of 9 endophytic fungi out of which the highest amount (44%) accounted was from the twigs. A sample of the immediate layer of soil adhering to the root of M. cordata was utilized to isolate 15 rhizosphere fungi. Fusarium equiseti and Phoma medicaginis were endophytes that were identified based on colony and molecular characteristics. The broad spectrum of antimicrobial activity depicted by F. equiseti (MK517551) was found to be significantly greater (p≤0.05, inhibitory against Bacillus cereus ATCC 11778, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 25853) than P. medicaginis (MK517550) (inhibitory against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 25853) as assessed using the Kirby-Bauer disk diffusion method. Trichoderma virens and Trichoderma asperellum were rhizospere fungi that exhibited remarkable antimicrobial properties against the test pathogens chosen for the study. T. asperellum indicated significantly greater bioactivity against all four bacterial pathogens and Candida albicans ATCC 10231 under study. The ranges of minimum inhibitory concentrations (MICs) of the fungi depicting antimicrobial properties were determined. The results obtained suggest that F. equiseti, P. medicaginis, T. asperellum, and T. virens of M. cordata harness bioprospective values as natural drug candidates. This is the first report on isolation and evaluation of the antimicrobial properties of endophytic and rhizosphere fungi of Mikania cordata.

scholarly journals Characterization of SCCmec, spa types and Multi Drug Resistant of methicillin-resistant Staphylococcus aureus isolates among inpatients and outpatients in a referral hospital in Shiraz, Iran

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Zahra Hashemizadeh ◽  
Nahal Hadi ◽  
Samane Mohebi ◽  
Davood Kalantar-Neyestanaki ◽  
Abdollah Bazargani
Keyword(s):  
Staphylococcus Aureus ◽  
Diffusion Method ◽  
Biochemical Tests ◽  
Spa Typing ◽  
Disk Diffusion Method ◽  
Methicillin Resistant ◽  
Tertiary Hospitals ◽  
Antimicrobial Susceptibility Tests ◽  
Susceptibility Tests ◽  
Spa Types

Abstract Objectives Molecular typing such as spa typing is used to control and prevent Staphylococcus aureus widespread in hospitals and communities. Hence, the aim of this study was to find the most common types of S. aureus strain circulating in Shiraz via spa and SCCmec typing methods. Results Total of 159 S. aureus isolates were collected from two tertiary hospitals in Shiraz. Isolates were identified by biochemical tests. Antimicrobial susceptibility tests were performed by standard disk diffusion method and then genetic analysis of bacteria was performed using SCCmec and spa typing. In this study 31.4% of the isolates were methicillin-resistant S. aureus. The majority of isolates were SSCmec type III. Spa type t030 was the most prominent type among MRSA strains. For the first time in Iran, spa003, t386, t1877, t314, t186, t1816, t304, t325, t345 were reported in this study. It was shown that there is a possibility that these spa types are native to this region. Our findings showed that SCCmec II, III and IV disseminate from hospital to community and vice versa. Thus, effective monitoring of MRSA in hospital and community is necessary.

scholarly journals Genetic Characterization of Methicillin-Resistant Staphylococcus aureus Isolates from Human Bloodstream Infections: Detection of MLSB Resistance

Antibiotics ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 375
Author(s):  
Vanessa Silva ◽  
Sara Hermenegildo ◽  
Catarina Ferreira ◽  
Célia M. Manaia ◽  
Rosa Capita ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Agents ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Bloodstream Infections ◽  
Disk Diffusion ◽  
Diffusion Method ◽  
Accessory Gene ◽  
Spa Typing ◽  
Disk Diffusion Method ◽  
Methicillin Resistant

In this study we aimed to characterize antimicrobial resistance in methicillin-resistant Staphylococcus aureus (MRSA) isolated from bloodstream infections as well as the associated genetic lineages of the isolates. Sixteen MRSA isolates were recovered from bacteremia samples from inpatients between 2016 and 2019. The antimicrobial susceptibility of these isolates was tested by the Kirby–Bauer disk diffusion method against 14 antimicrobial agents. To determine the macrolide–lincosamide–streptogramin B (MLSB) resistance phenotype of the isolates, erythromycin-resistant isolates were assessed by double-disk diffusion (D-test). The resistance and virulence genes were screened by polymerase chain reaction (PCR). All isolates were characterized by multilocus sequence typing (MLST), spa typing, staphylococcal chromosomal cassette mec (SCCmec) typing, and accessory gene regulator (agr) typing. Isolates showed resistance to cefoxitin, penicillin, ciprofloxacin, erythromycin, fusidic acid, clindamycin, and aminoglycosides, confirmed by the presence of the blaZ, ermA, ermC, mphC, msrA/B, aac(6’)-Ie-aph(2’’)-Ia, and ant(4’)-Ia genes. Three isolates were Panton–Valentine-leukocidin-positive. Most strains (n = 12) presented an inducible MLSB phenotype. The isolates were ascribed to eight spa-types (t747, t002, t020, t1084, t008, t10682, t18526, and t1370) and four MLSTs (ST22, ST5, ST105, and ST8). Overall, most (n = 12) MRSA isolates had a multidrug-resistance profile with inducible MLSB phenotypes and belonged to epidemic MRSA clones.

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