Table 1. Antimicrobial susceptibility of the methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered in 1998 and 2008 from a Brazilian tertiary hospital.
| Antimicrobial agent | Number of susceptible isolates (%) | |
|---|---|---|
| 1998 (N = 48) | 2008 (N = 56) | |
| Chloramphenicol | 2 (4.2) | 39 (69.6)a* |
| Ciprofloxacin | 0 (0) | 1 (1.8) |
| Clindamycin | 0 (0) | 2 (3.6) |
| Erythromycin | 0 (0) | 0 (0) |
| Gentamicin | 0 (0) | 4 (7.1) |
| Linezolid | 48 (100) | 56 (100) |
| Norfloxacin | 0 (0) | 2 (3.6) |
| Rifampicin | 7 (14.6) | 24 (42.9)b* |
| Tetracycline | 3 (6.3) | 6 (10.7) |
| Trimethoprim-sulfamethoxazole | 0 (0) | 8 (14.3)c* |
| Vancomycin | 48 (100) | 56 (100) |
a
Thirty-one (79.5%) of the 39 and
b
17 (70.8%) of the 24 MRSA isolates susceptible to chloramphenicol and rifampicin, respectively, carried SCCmec III.
c
None of the 8 MRSA isolates susceptible to trimethoprim-sulfamethoxazole carried SCCmec III. SCCmec III = staphylococcal chromosomal cassette mec III; MRSA = methicillin-resistant Staphylococcus aureus.
*
P < 0.05 compared to 1998 (chi-square or Fisher exact test).