Investigating the relation between resistance pattern and type of Staphylococcal cassette chromosome (SCC) in methicillin-resistant .

BACKGROUND AND OBJECTIVES

MRSA became a widely recognized cause of mortality worldwide with necessity of its epidemiological pattern study. Typing of MRSA isolates was performed molecularly based on SCC type and relation to resistance pattern was investigated.

MATERIALS AND METHODS

Out of 200 clinical specimens, was detected phenotypically and confirmed as MRSA by PCR in 124 isolates obtained from associated laboratories of different hospitals of Zagazig, during 2018-2019. Antimicrobial resistance pattern was detected and MRSA SCC was typed by two methods.

RESULTS

rate was high in wounds, sputum, blood, and urine isolates. Antimicrobial resistance rates against cefotaxime, tetracycline, gentamicin, ciprofloxacin, erythromycin, azithromycin, clindamycin, chloramphenicol, sulfamethoxazole-trimethoprim, linezolid and vancomycin were 82.3%, 65.3%, 56.4%, 45.1%, 37.1%, 32.3%, 32.3%, 25%, 7.3%, 2.4% and 0%, respectively. Multiplex-PCR(M-PCR) was able to detect SCC element among 57% of isolates classified as SCC II (n=40), III (n=21), IVa (n=3), IVd (n=2), V(n=1), and four isolates contain both SCC II and SCC IV. Traditional typing by PCR for and gene complexes was almost concordant with M-PCR. Furthermore, it was able to identify SCC types VI, IX, and XIV among 1, 3 and 18 isolates, respectively. No Statistical correlation was established between type of cassette and rate of antimicrobial resistance. Phylogenetic analysis reveals that all types were related to each other and no significant variation in the same type of different SCC cassettes.

CONCLUSION

Most MRSA isolates were MDR reflecting antimicrobials misuse. Detection of various SCC types among MRSA isolates indictae the complexity of MRSA epidemiology and increase chance for gene sharing creating new types. The presented investigation was important in understanding MRSA epidemiology and diversity in Egypt providing advice for improving therapeutic protocols.