Volume 12, Number 4—April 2006
Research
Contrasting Pediatric and Adult Methicillin-resistant Staphylococcus aureus Isolates
, Susan E. Crawford*, Susan Boyle-Vavra*, Mark A. Hostetler*, Daniel C. Kim*, and Robert S. Daum*
Table 2
Percentage of methicillin-resistant Staphylococcus aureus isolates resistant to non–β-lactam antimicrobial drugs among pediatric and adult patients, stratified by hospital- and community-associated designation
| Antimicrobial drug | Adult outpatient isolates (n = 105) | Pediatric outpatient isolates (n = 115) | p value* |
|---|---|---|---|
| Ciprofloxacin | 55.2 | 9.6 | <0.001 |
| Clindamycin | |||
| Resistant† | 37.1 | 6.1 | <0.001 |
| D-test positive‡ | 20.4 | 14.8 | 0.39 |
| Erythromycin | 91.4 | 88.7 | 0.16 |
| Gentamicin | 8.6 | 1.7 | 0.03 |
| Rifampin | 1.9 | 0 | 0.23 |
| Tetracycline§ | 13.3 | 3.6 | 0.01 |
| TMP-SMX¶ | 0 | 0 | NA |
| Vancomycin | 0 | 0 | NA |
*p value compares resistance to indicated antimicrobial drugs or positive test result among adult vs. pediatric isolates by χ2 test or Fisher exact test. NA, not applicable.
†Figures in this row represent Vitek testing results for clindamycin.
‡54 (97.1%) and 88 (93.9%) of the adult and pediatric isolates, respectively, that were erythromycin resistant and clindamycin susceptible by Vitek were evaluated by D-testing.
§Tetracycline susceptibility was not tested for 5 pediatric outpatient isolates and 2 adult outpatient isolates.
¶TMP-SMX, trimethoprim-sulfamethoxazole. Only 42 adult and 27 pediatric isolates that were erythromycin resistant and clindamycin susceptible were tested.