TABLE 1.
MICs of drugs against 221 pneumococcal strains
| Drug and type of strain testeda | MIC (μg/ml)b |
||
|---|---|---|---|
| Range | 50% | 90% | |
| Penicillin G | 0.008->16 | 1 | 4 |
| Penicillin S | 0.008-0.06 | 0.03 | 0.06 |
| Penicillin I | 0.125-1 | 0.5 | 1 |
| Penicillin R | 2->16 | 4 | 8 |
| Macrolide S | 0.015-8 | 1 | 2 |
| erm(B) | 0.03-16 | 1 | 4 |
| mef(A) | 0.008-4 | 0.125 | 4 |
| erm(A) | 0.03-0.03 | ||
| erm(B) mef(A) | 0.03-8 | 2 | 4 |
| L4 mutations | 1->16 | 4 | 16 |
| 23S rRNA mutations | 0.015-0.5 | ||
| Quinolone S | 0.008->16 | 1 | 4 |
| Quinolone R | 0.015-8 | 0.25 | 4 |
| CEM-101 | 0.002-1 | 0.03 | 0.25 |
| Penicillin S | 0.002-0.25 | 0.03 | 0.125 |
| Penicillin I | 0.002-0.25 | 0.03 | 0.25 |
| Penicillin R | 0.004-1 | 0.06 | 0.25 |
| Macrolide S | 0.002-0.015 | 0.008 | 0.015 |
| erm(B) | 0.004-1 | 0.03 | 0.5 |
| mef(A) | 0.008-0.25 | 0.03 | 0.125 |
| erm(A) | 0.008-0.015 | ----- | ----- |
| erm(B) mef(A) | 0.015-1 | 0.125 | 0.25 |
| L4 mutations | 0.03-0.125 | 0.06 | 0.125 |
| 23S rRNA mutations | 0.002-0.03 | ||
| Quinolone S | 0.002-1 | 0.03 | 0.25 |
| Quinolone R | 0.004-0.25 | 0.008 | 0.06 |
| Erythromycin | 0.03->64 | 64 | >64 |
| Penicillin S | 0.03->64 | 4 | >64 |
| Penicillin I | 0.03->64 | >64 | >64 |
| Penicillin R | 0.03->64 | >64 | >64 |
| Macrolide S | 0.03-0.25 | 0.06 | 0.125 |
| erm(B) | 16->64 | >64 | >64 |
| mef(A) | 1->64 | 4 | 32 |
| erm(A) | 2-4 | ||
| erm(B) mef(A) | 4->64 | >64 | >64 |
| L4 mutations | 4->64 | >64 | >64 |
| 23S rRNA mutations | 8->64 | ||
| Quinolone S | 0.03->64 | >64 | >64 |
| Quinolone R | 0.03->64 | 0.06 | >64 |
| Azithromycin | 0.06->64 | 16 | >64 |
| Penicillin S | 0.06->64 | 4 | >64 |
| Penicillin I | 0.06->64 | >64 | >64 |
| Penicillin R | 0.06->64 | >64 | >64 |
| Macrolide S | 0.06-0.25 | 0.125 | 0.0125 |
| erm(B) | >64->64 | >64 | >64 |
| mef(A) | 1->64 | 4 | 8 |
| erm(A) | 2-8 | ||
| erm(B) mef(A) | 2->64 | >64 | >64 |
| L4 mutations | 2->64 | >64 | >64 |
| 23S rRNA mutations | 32->64 | ||
| Quinolone S | 0.06->64 | >64 | >64 |
| Quinolone R | 0.06->64 | 0.125 | >64 |
| Clarithromycin | 0.125->64 | 8 | >64 |
| Penicillin S | 0.015->64 | 1 | >64 |
| Penicillin I | 0.03->64 | 16 | >64 |
| Penicillin R | 0.015->64 | 16 | >64 |
| Macrolide S | 0.015-0.06 | 0.03 | 0.06 |
| erm(B) | 4->64 | >64 | >64 |
| mef(A) | 0.5-32 | 2 | 4 |
| erm(A) | 0.25-0.5 | ||
| erm(B) mef(A) | 1->64 | >64 | >64 |
| L4 mutations | 1-32 | 16 | 32 |
| 23S rRNA mutations | 8-16 | ||
| Quinolone S | 0.015->64 | 16 | >64 |
| Quinolone R | 0.015->64 | 0.03 | >64 |
| Telithromycin | 0.015-2 | 0.06 | 0.5 |
| Penicillin S | 0.015-1 | 0.06 | 0.25 |
| Penicillin I | 0.015-1 | 0.06 | 0.5 |
| Penicillin R | 0.015-2 | 0.125 | 0.5 |
| Macrolide S | 0.015-0.03 | 0.03 | 0.03 |
| erm(B) | 0.03-2 | 0.06 | 1 |
| mef(A) | 0.03-0.5 | 0.125 | 0.25 |
| erm(A) | 0.03-0.06 | ||
| erm(B) mef(A) | 0.03-2 | 0.5 | 1 |
| L4 mutations | 0.06-0.25 | 0.125 | 0.25 |
| 23S rRNA mutations | 0.03-0.06 | ||
| Quinolone S | 0.015-2 | 0.125 | 0.5 |
| Quinolone R | 0.015-1 | 0.03 | 0.125 |
| Clindamycin | 0.015->64 | 0.06 | >64 |
| Penicillin S | 0.03->64 | 0.06 | >64 |
| Penicillin I | 0.03->64 | 0.125 | >64 |
| Penicillin R | 0.015->64 | 0.06 | >64 |
| Macrolide S | 0.015-0.06 | 0.03 | 0.06 |
| erm(B) | 0.06->64 | >64 | >64 |
| mef(A) | 0.03-0.125 | 0.06 | 0.06 |
| erm(A) | 0.125-0.25 | ||
| erm(B) mef(A) | 0.03->64 | 0.06 | >64 |
| L4 mutations | 0.03-0.125 | 0.06 | 0.125 |
| 23S rRNA mutations | 0.03-1 | ||
| Quinolone S | 0.015->64 | 0.06 | >64 |
| Quinolone R | 0.03-64 | 0.03 | 64 |
| Amoxicillin-clavulanate | 0.015-16 | 0.05 | 8 |
| Penicillin S | 0.015-0.125 | 0.03 | 0.06 |
| Penicillin I | 0.03-2 | 0.5 | 1 |
| Penicillin R | 0.125-16 | 2 | 8 |
| Macrolide S | 0.015-8 | 0.5 | 2 |
| erm(B) | 0.015-8 | 0.5 | 8 |
| mef(A) | 0.015-8 | 0.125 | 2 |
| erm(A) | 0.03-0.03 | ||
| erm(B) mef(A) | 0.03-16 | 2 | 8 |
| L4 mutations | 0.125-8 | 4 | 8 |
| 23S rRNA mutations | 0.03-0.06 | ||
| Quinolone S | 0.015-16 | 1 | 8 |
| Quinolone R | 0.015-4 | 0.5 | 2 |
| Levofloxacin | 0.06-32 | 1 | 8 |
| Penicillin S | 0.06-32 | 1 | 16 |
| Penicillin I | 1-32 | 1 | 2 |
| Penicillin R | 0.5-16 | 1 | 2 |
| Macrolide S | 1-32 | 1 | 16 |
| erm(B) | 0.5-32 | 1 | 2 |
| mef(A) | 0.5-8 | 1 | 2 |
| erm(A) | 1-1 | ||
| erm(B) mef(A) | 1-16 | 1 | 16 |
| L4 mutations | 0.5-16 | 1 | 2 |
| 23S rRNA mutations | 0.06-1 | ||
| Quinolone S | 0.06-2 | 1 | 2 |
| Quinolone R | 4-32 | 16 | 16 |
| Moxifloxacin | 0.125-8 | 0.25 | 2 |
| Penicillin S | 0.125-8 | 0.5 | 4 |
| Penicillin I | 0.125-4 | 0.25 | 0.5 |
| Penicillin R | 0.125-4 | 0.25 | 0.5 |
| Macrolide S | 0.125-8 | 0.25 | 4 |
| erm(B) | 0.125 | 0.25 | 0.5 |
| mef(A) | 0.125-4 | 0.25 | 0.5 |
| erm(A) | 0.25-0.5 | ||
| erm(B) mef(A) | 0.125-2 | 0.25 | 0.5 |
| L4 mutations | 0.125-4 | 0.25 | 0.5 |
| 23S rRNA mutations | 0.25-0.5 | ||
| Quinolone S | 0.125-1 | 0.25 | 0.5 |
| Quinolone R | 0.5-8 | 4 | 4 |
a
S, susceptible; I, intermediate; R, resistant. A total of 53 penicillin-susceptible, 63 penicillin-intermediate, 105 penicillin-resistant, 50 macrolide-susceptible, 54 erm(B), 51 mef(A), 4 erm(A), and 31 erm(B) mef(A) strains, 27 strains with L4 mutations, 4 strains with 23S rRNA mutations, 195 quinolone-susceptible strains, and 27 quinolone-resistant strains were tested.
b
50% and 90%, MICs at which 50% and 90% of isolates, respectively, are inhibited.