Inducible clindamycin resistance in erythromycin-resistant, non-multiresistant, methicillin-resistant Staphylococcus aureus

Background Resistance to antimicrobial agents is prevalent among Staphylococci. This has led to wide uses of macrolide-lincosamide-streptogramin B (MLSB) antibiotics to Staphylococcus aureus (S. aureus) infections. MLSB though chemically distinct, have similar target site and mode of action. The multiple mechanisms are responsible for resistance to MLSB antibiotics which can lead to clinical failure. The aim of the study was to investigate the frequency of inducible and constitutive clindamycin resistance among clinical isolates of S. aureus and their relationship with Methicillin-resistant Staphylococcus aureus (MRSA).Material & Methods A total of 336 unique Staphylococcus aureus isolates from different clinical samples obtained from patients were studied. Antibiotic susceptibility test was performed by Kirby- Bauer disc diffusion method. “D test” was performed to detect inducible clindamycin resistance as per CLSI guidelines. MRSA was detected using Cefoxitin (30μg) and results were interpreted according to CLSI criteria.Results Inducible clindamycin resistance was seen in 45 (13.39%), constitutive clindamycin resistance was seen among 58 (17.26%) while MS phenotype was observed among 38(11.30%) of isolates. Inducible resistance as well as constitutive resistance was higher among MRSA as compared to MSSA (21.11%, 4.48% and 21.11%, 12.82%respectively).Conclusion The Successful use of clindamycin for the treatment of infection caused by S. aureus can be predicted based on the result of simple and inexpensive D test.Journal of Nobel Medical CollegeVolume 5, Number 1, Issue 8, January-July 2016, 1-5

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Prevalence of inducible clindamycin resistance in methicillin-resistant Staphylococcus aureus: the first study in Jordan

The Journal of Infection in Developing Countries ◽

10.3855/jidc.8316 ◽

2017 ◽

Vol 11 (04) ◽

pp. 350-354 ◽

Cited By ~ 9

Author(s):

Dua’a Jarajreh ◽

Amin Aqel ◽

Hamed Alzoubi ◽

Wael Al-Zereini

Keyword(s):

Staphylococcus Aureus ◽

Polymerase Chain Reaction ◽

Methicillin Resistant Staphylococcus Aureus ◽

High Rate ◽

Chain Reaction ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance ◽

Standard Procedures ◽

Polymerase Chain

Introduction: A high rate of infections with methicillin-resistant Staphylococcus aureus (MRSA) has been documented, in both hospital- (HA-MRSA) and community-acquired (CA-MRSA) diseases in Jordan. Erythromycin and clindamycin are considered treatments of choice. However, resistance to erythromycin with false susceptibility to clindamycin in vitro may lead to therapeutic failure. Hence, it is mandatory to study the prevalence of inducible resistance to macrolide-lincosamide-streptogramin B (iMLSB) antibiotics conferred by erm genes in those bacteria. Methodology: S. aureus isolates were identified morphologically and biochemically, and MRSA were appraised using standard procedures. Induction in resistance to MLSB antibiotics among MRSA isolates was detected phenotypically using the D-test, and the presence of erm genes was revealed by polymerase chain reaction (PCR). Results: Of 126 collected Staphylococcus isolates, 71 (56.3%) isolates were S. aureus, of which 55 (77.5%) were MRSA. A total of 43 (78.2%) MRSA-discordant isolates were resistant to erythromycin, of which 33 (76.7%) exhibited the iMLSB (D-test positive), 2 (4.7%) the MSB (D-test negative), and 8 (18.6%) the constitutive resistant (cMLSB) phenotypes. Induction of clindamycin resistance was 1.6 times greater in CA-MRSA than in HA-MRSA. Furthermore, ermA and ermC were significantly prevalent in HA-MRSA and CA-MRSA, respectively. Conclusions: Continuous surveillance of the MLSB resistance is important and required before the prescription of clindamycin to treat MRSA infections.

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Characteristics of Erythromycin Resistance in Methicillin-Resistant Staphylococcus aureus Isolated From Raw Milk

International Journal of Enteric Pathogens ◽

10.15171/ijep.2019.25 ◽

2019 ◽

Vol 7 (4) ◽

pp. 121-125

Author(s):

Fatemeh Mahdavi ◽

Fatemeh Zaboli ◽

Rahem Khoshbakht

Keyword(s):

Staphylococcus Aureus ◽

Resistance Genes ◽

Methicillin Resistant Staphylococcus Aureus ◽

Methicillin Resistance ◽

Meca Gene ◽

Raw Milk ◽

Erythromycin Resistance ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance ◽

Mrsa Strains

Background: Methicillin-resistant Staphylococcus aureus (MRSA) strains are one of the most important multidrug resistant microorganisms that threaten human health. Objective: The present study was conducted to evaluate genotypic and phenotypic characteristics of erythromycin resistance among MRSA isolates recovered from raw milk in Iran. Materials and Methods: A total of 50 MRSA isolates were recovered from raw milk. Tests for erythromycin and clindamycin susceptibility and inducible clindamycin resistance were done. In addition, the presence of the methicillin resistance determinant (mecA), erythromycin resistance genes (ermA, ermB, ermC and msrA) and an important virulence gene (Panton– Valentine leukocidin) were investigated using polymerase chain reaction (PCR) method. Results: Forty-eight percent (24/50) and 46% (23/50) of the isolates were resistant to erythromycin and clindamycin, respectively. Seven (14%) isolates showed inducible clindamycin resistance phenotype. The mecA gene was detected in 88% (44/50) of MRSA isolates. The incidence of the ermA, ermB, ermC and msrA genes was 14%, 64%, 12%, and 26%, respectively and the PVL gene was present in 18% (9/50) of MRSA isolates. Conclusion: According to the results of the study, the incidence of erythromycin resistance genes and inducible clindamycin-resistant MRSA strains was high in raw milk samples in Iran.

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Phenotypic characterization and Molecular detection of Inducible and Constitutive Clindamycin resistance among Staphylococcus aureus isolates in a Tertiary Care Hospital

Research Journal of Pharmacy and Technology ◽

10.52711/0974-360x.2021.00658 ◽

2021 ◽

pp. 3799-3804

Author(s):

Mahalakshmi G. ◽

Neelusree P. ◽

Kalyani M.

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Tertiary Care ◽

Phenotypic Characterization ◽

Clinical Samples ◽

Resistance Pattern ◽

Care Hospital ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance ◽

Significant Difference

Background: Staphylococcus aureus is Gram positive cocci. The pyogenic bacteria which is responsible for a variety of diseases that ranges in severity from mild skin and soft tissue infections to life-threatening conditions such as endocarditis, pneumonia, and sepsis. There is a scenario of increasing Methicillin-resistant Staphylococcus aureus (MRSA) infections, the macrolide-lincosamide-streptogramin B (MLSB) group of antibiotics they have different structure with same mechanism of action which serves as one good alternative. There is a frequency of increasing Methicillin Resistant Staphylococcus aureus (MRSA) infections and their change in antimicrobial resistance pattern. There is a concern about use of this antibiotic in the presence of Erythromycin resistance because of the possibility of inducible resistance among the members of Macrolide, lincosamide, Strepto-gramin B (MLSB) group. The invitro resistance exhibited by Staphylococcus aureus to erythromycin, Clindamycin, and other drugs of MLSB groups is due to the expression of ribosomal methylases(erm) genes. The detection of inducible Clindamycin resistance can limit the effectiveness of these drugs. Objective of the study: To isolate of Staphylococcus aureus from various clinical samples to differentiate between Methicillin resistant Staphylococcus aureus (MRSA) and Methicillin sensitive Staphylococcus aureus (MSSA) by conventional methods. To detect inducible and constitutive Clindamycin resistance in Staphylococcus aureus isolates by D test. To detect ermA gene responsible for resistance by PCR. Methodology: This cross sectional study was done for a period of six months. Totally 106 Staphylococcus aureus isolates was obtained various clinical samples were processed using standard guidelines. Result: From the 106 isolates of Staphylococcus aureus 67(63.3%) were MSSA and 39(36.7%) were MRSA. D-test was positive in n=9 of the n=21 MRSA and n=17 of the n=85 MSSA, which denotes inducible Clindamycin resistance. N- 9 of MRSA and n=13(22%) of MSSA showed Constitutional Clindamycin resistance. The statistics show that there is a significant Difference in constitutive resistance between MRSA and MSSA. In India ermA gene is most prevalent, out of 22 d-test positive n=13 ermA gene were detected (n=3-MRSA and n=10-MSSA) by using conventional PCR. Conclusion: The MLSB family of antibiotics is one such alternative and CD is preferred. Clinical microbiology laboratories should report inducible Clindamycin resistance in Staphylococcus aureus and D-test can be used as a simple, auxiliary and reliable method to Delineate inducible and constitutive Clindamycin resistance in routine clinical laboratories.

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PREVALENCE OF INDUCIBLE CLINDAMYCIN RESISTANCE IN CLINICAL ISOLATES OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS MEDIATED THROUGH GENE ERMC EXPRESSION

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i9.25928 ◽

2018 ◽

Vol 11 (9) ◽

pp. 106

Author(s):

Nimisha Tandon ◽

Madhuri Kulkarni ◽

Sowmya Gs ◽

Fauzia Tabassum ◽

Sayeed Akhtar Md

Keyword(s):

Staphylococcus Aureus ◽

Methicillin Resistant Staphylococcus Aureus ◽

Good Alternative ◽

Clinical Isolates ◽

University Teaching ◽

Diffusion Method ◽

Disc Diffusion ◽

Cross Sectional ◽

Methicillin Resistant ◽

Inducible Clindamycin Resistance

Objective: The objective of this study is to determine the phenotypic and genotypic expression of inducible clindamycin resistance due to the expression of ermA, ermB, and ermC genes in clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) by double disc diffusion and uniplex PCR.Method: This cross-sectional study was conducted in microbiology department of an university teaching hospital. A total of 604 non-duplicate clinical isolates of S. aureus evaluated for MRSA and were subjected to uniplex PCR for ermA, ermB, and ermC genes, respectively.Result: The analysis of 604 isolates showed that 220 (36.42%) were of MRSA. Out of which, 69 (11.42%) were demonstrated as inducible clindamycin resistance by double-disc diffusion method, and among inducible resistant isolates, 25 isolates of ermC (84%) were positive and 4 (16%) were negative, whereas, ermA and ermB genes could not be demonstrated by the genotypic method.Conclusion: We observed that clindamycin may serve as a good alternative and advocated in severe MRSA infection based on susceptibility pattern. We observed D test as a mandatory method to detect inducible clindamycin Staphylococcus. Importantly, ermC gene is a major determinant of resistance to macrolides among MRSA.

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