Disks with oxacillin
on the sensitivity of microorganisms to antibiotics
Isolates from his third incident infection culture in August 2012 showed the same molecular characteristics as previous samples, but 2 different susceptibility patterns: 1 isolate was the same as previous, while another showed additional phenotypic resistance to oxacillin
(MIC 4 [micro]g/mL by broth dilution), making this a borderline-resistant S.
A dilution series was prepared using oxacillin
aureus being resistant to oxacillin
(MRSA) decreased from 47.
was used to detect resistant isolates of S.
23% of hospital sites including the skin of the healthcare providers; 14% of these strains were oxacillin
resistant, thus S.
It was utilized disks with 12 antibiotics of ordinary use, for the Gram positive bacteria: cefepime (COM, 30 [micro]g), ciprofloxacin (CIP, 5 [micro]g), clindamycin (CLI, 2 [micro]g), chloramphenicol (CLO, 30 gg), erythromycin (ERI, 15 [micro]g), gentamicin (GEN, 10 [micro]g), oxacillin
(OXA, 1 [micro]g), penicillin G (PEN, 10 un), rifampicin (RIF, 5 [micro]g), sulfazotrim (SUT, 23.
12 The antibiotics that were used against gram-positive bacteria were (20 ug of amoxicillin + 10 ug of clavulanate), ceftazidime (30ug), cephalothin (30ug), clindamycin (2ug), erythromycin (15ug), gentamycin (10ug), oxacillin
(1ug), penicillin (10ug) and vancomycin (30ug).
The antimicrobial agents tested were oxacillin
, vancomycin, erythromycin, tetracycline, levofloxacin, clindamycin, trimethoprim-sulfamethoxazole, and linezolid.
The Clinical and Laboratory Standards Institute (CLSI) (4) states that the 1-[micro]g oxacillin
disk diffusion (ODD) test is an effective screening method commonly used in clinical laboratories for the detection of penicillin-resistant pneumococci.
aureus isolates, classified as MRSA if found resistant to cefoxitin, methicillin, or oxacillin
and as methicillin susceptible (MSSA) if susceptible to those antimicrobials.
The emergence of high level resistance to penicillin way back in 1948 followed by development and spread of the strains resistant to synthetic penicillin's (methicillin, oxacillin
, and naficillin), macrolides, tetracycline, and aminoglycosides has made the therapy of Staphylococcal infections a global challenge.