Table 4.
Antimicrobial nonsusceptibility in relation to PI carriage among serotype 19A pneumococci
| Antimicrobial | PI-negative* (n = 20) | PI-positive* (n = 29) | P† |
|---|---|---|---|
| No. (%) of nonsusceptible isolates | |||
| PEN | 14 (70%) | 29 (100%) | <0·001 |
| AMX | 0 | 28 (97%) | <0·001 |
| CTX | 0 | 23 (79%) | <0·001 |
| ERY | 7 (35%) | 22 (76%) | 0·004 |
| CLI | 4 (20%) | 16 (55%) | 0·003 |
| SXT | 16 (80%) | 17 (59%) | 0·117 |
| CHL | 1 (5%) | 7 (24%) | 0·075 |
| TET | 16 (80%) | 20 (69%) | 0·390 |
| MDR (yes) | 6 (30%) | 19 (66%) | 0·015 |
AMX, amoxicillin; CHL, chloramphenicol; CLI, clindamycin; CTX, ceftriaxone; ERY, erythromycin; MDR, multidrug resistant; PEN, penicillin; SXT, trimethoprim/sulfamethoxazole; TET, tetracycline.
*
PI, pilus islet. PI-negative, isolates carrying none of the PI; PI-positive, isolates carrying PI1 or both PI1 and PI2.
†
Statistically significant differences in proportions of nonsusceptible isolates among PI-negative and PI-positive pneumococci are in bold typeface.