TABLE 1.
Susceptibility of S. pneumoniae to all antimicrobials tested
| Antimicrobial agent and phenotypea (no. of isolates) | MIC (μg/ml)
|
% of isolates that were:
|
||||
|---|---|---|---|---|---|---|
| Range | Mode | 90% | S | I | R | |
| Penicillin | ||||||
| All | ≤0.03–>8 | ≤0.03 | 2 | 63.9 | 22.5 | 13.7 |
| Pen S | ≤0.03–0.06 | ≤0.03 | 0.06 | 100.0 | 0.0 | 0.0 |
| Pen I | 0.12–1 | 1 | 1 | 0.0 | 100.0 | 0.0 |
| Pen R | 2–>8 | 2 | 4 | 0.0 | 0.0 | 100.0 |
| Amoxicillin-clavulanate | ||||||
| All | ≤0.01–>16 | ≤0.01 | 1 | 81.5 | 9.3 | 9.2 |
| Pen S | ≤0.01–0.5 | ≤0.01 | 0.03 | 100.0 | 0.0 | 0.0 |
| Pen I | ≤0.01–4 | 0.5 | 1 | 76.1 | 19.7 | 4.2 |
| Pen R | 0.25–>16 | 2 | 4 | 4.2 | 35.6 | 60.3 |
| Cefuroxime | ||||||
| All | ≤0.12–64 | ≤0.12 | 4 | 71.9 | 3.4 | 24.8 |
| Pen S | ≤0.12–1 | ≤0.12 | ≤0.12 | 100.0 | 0.0 | 0.0 |
| Pen I | ≤0.12–16 | 2 | 4 | 35.5 | 14.8 | 49.7 |
| Pen R | ≤0.12–64 | 4 | 8 | 0.3 | 0.1 | 99.6 |
| Ceftriaxone | ||||||
| All | ≤0.01–8 | ≤0.01 | 1 | 84.6 | 11.2 | 4.1 |
| Pen S | ≤0.01–0.5 | ≤0.01 | ≤0.06 | 100.0 | 0.0 | 0.0 |
| Pen I | ≤0.01–8 | 0.5 | 1 | 35.5 | 14.8 | 49.7 |
| Pen R | ≤0.01–8 | 1 | 2 | 13.9 | 60.3 | 25.8 |
| Erythromycin | ||||||
| All | ≤0.03–>4 | ≤0.03 | 4 | 75.9 | 0.1 | 24.0 |
| Pen S | ≤0.03–>4 | ≤0.03 | 0.03 | 93.9 | 0.0 | 6.1 |
| Pen I | ≤0.03–>4 | ≤0.03 | >4 | 54.1 | 0.5 | 45.5 |
| Pen R | ≤0.03–>4 | 4 | >4 | 27.5 | 0.1 | 72.3 |
| Azithromycin | ||||||
| All | ≤0.03–>4 | ≤0.03 | 4 | 75.9 | 3.4 | 20.6 |
| Pen S | ≤0.03–>4 | ≤0.03 | 0.06 | 93.9 | 0.8 | 5.3 |
| Pen I | ≤0.03–>4 | ≤0.03 | >4 | 54.3 | 7.8 | 37.9 |
| Pen R | ≤0.03–>4 | >4 | >4 | 27.5 | 8.4 | 64.0 |
| Clarithromycin | ||||||
| All | ≤0.01–>32 | 0.03 | 4 | 75.9 | 3.4 | 20.6 |
| Pen S | ≤0.01–>32 | 0.03 | 0.03 | 93.9 | 0.4 | 5.7 |
| Pen I | ≤0.01–>32 | 0.03 | 32 | 54.2 | 2.1 | 43.7 |
| Pen R | ≤0.01–>32 | 2 | >32 | 27.5 | 1.4 | 71.0 |
| Levofloxacin | ||||||
| All | ≤0.004–>8 | 0.5 | 1 | 99.8 | 0.0 | 0.2 |
| Pen S | ≤0.004–>8 | 0.5 | 1 | 93.9 | 0.0 | 0.0 |
| Pen I | ≤0.004–>8 | 0.5 | 1 | 99.8 | 0.0 | 0.2 |
| Pen R | 0.12–>8 | 0.5 | 1 | 99.4 | 0.0 | 0.6 |
| Grepafloxacin | ||||||
| All | ≤0.002–>4 | 0.12 | 0.25 | 99.8 | 0.1 | 0.1 |
| Pen S | ≤0.002–1 | 0.12 | 0.25 | 99.9 | 0.1 | 0.0 |
| Pen I | ≤0.004–>4 | 0.12 | 0.25 | 99.8 | 0.0 | 0.2 |
| Pen R | ≤0.01–>4 | 0.12 | 0.25 | 99.2 | 0.1 | 0.6 |
| Sparfloxacin | ||||||
| All | ≤0.002–>4 | 0.25 | 0.5 | 99.8 | 0.0 | 0.2 |
| Pen S | ≤0.002–2 | 0.25 | 0.5 | 99.9 | 0.0 | 0.1 |
| Pen I | 0.004–>4 | 0.25 | 0.5 | 99.8 | 0.0 | 0.2 |
| Pen R | 0.03–>4 | 0.25 | 0.5 | 99.2 | 0.1 | 0.6 |
| Moxifloxacinb | ||||||
| All | ≤0.002–4 | 0.12 | 0.25 | 99.8 | 0.1 | 0.1 |
| Pen S | ≤0.002–2 | 0.12 | 0.25 | 100.0 | 0.0 | 0.0 |
| Pen I | ≤0.002–4 | 0.12 | 0.25 | 99.8 | 0.1 | 0.2 |
| Pen R | 0.01–4 | 0.12 | 0.25 | 99.4 | 0.5 | 0.1 |
| Trovafloxacin | ||||||
| All | ≤0.002–4 | 0.12 | 0.12 | 99.9 | 0.1 | 0.1 |
| Pen S | ≤0.002–1 | 0.12 | 0.12 | 100.0 | 0.0 | 0.0 |
| Pen I | 0.004–4 | 0.12 | 0.12 | 99.8 | 0.1 | 0.2 |
| Pen R | 0.01–4 | 0.12 | 0.12 | 99.5 | 0.4 | 0.1 |
| SXT | ||||||
| All | ≤0.01–>4 | 0.12 | 4 | 67.1 | 16.5 | 16.4 |
| Pen S | ≤0.01–>4 | 0.12 | 1 | 89.5 | 4.9 | 5.6 |
| Pen I | ≤0.01–>4 | 2 | 4 | 40.2 | 35.3 | 24.5 |
| Pen R | 0.06–>4 | 4 | >4 | 6.6 | 39.9 | 53.5 |
a
Pen, penicillin; S, susceptible; I, intermediate; R, resistant. Of the 5,640 S. pneumoniae isolates, 3,603 were Pen S, 1,267 were Pen I, and 770 were Pen R.
b
Moxifloxacin interpretive breakpoints based on U.S. FDA breakpoints.