Table 5.
Minimal inhibitory concentrations (MIC) for selected β-lactam antibiotics for 55 pneumococcal isolates obtained during AOM and post-treatment visits
| Antibiotics | Number of strains with MIC (mg/L) | Range | MIC50 | MIC90 | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ≤0.023 | 0.064 | 0.12 | 0.19 | 0.38 | 0.5 | 0.75 | 1.0 | 1.5 | 2 | 3 | 4 | 16 | 24 | 32 | 48 | 64 | ≥256 | |||||
| Penicilin | MEF AOM | 4 | 1 | 1 | 2 | 4 | 3 | 1 | 1 | 0.023–2.0 | 0.75 | 2.0 | ||||||||||
| NP/OP AOM | 3 | 1 | 1 | 2 | 4 | 3 | 1 | 2 | 0.023–2.0 | 0.75 | 2.0 | |||||||||||
| PT visit | 1 | 2 | 1 | 4 | 3 | 1 | 0.19–2.0 | 1.0 | 2.0 | |||||||||||||
| Ampicillin | MEF AOM | 4 | 1 | 2 | 2 | 5 | 1 | 2 | 0.023–3.0 | 0.75 | 3.0 | |||||||||||
| NP/OP AOM | 3 | 1 | 1 | 2 | 2 | 4 | 2 | 2 | 0.023–3.0 | 0.75 | 3.0 | |||||||||||
| PT visit | 1 | 2 | 2 | 1 | 2 | 1 | 2 | 1 | 0.12–4.0 | 1.0 | 3.0 | |||||||||||
| Cefaclor | MEF AOM | 4 | 1 | 1 | 1 | 2 | 5 | 1 | 1 | 1 | 0.38–256 | 24 | 64 | |||||||||
| NP/OP AOM | 3 | 1 | 1 | 1 | 1 | 2 | 5 | 1 | 2 | 0.38–256 | 24 | 256 | ||||||||||
| PT visit | 1 | 1 | 1 | 2 | 3 | 1 | 1 | 2 | 1.5–256 | 32 | 256 | |||||||||||
| Cefotaxime | MEF AOM | 4 | 1 | 2 | 1 | 3 | 4 | 1 | 1 | 0.023–1.5 | 0.5 | 1.0 | ||||||||||
| NP/OP AOM | 3 | 1 | 1 | 2 | 1 | 3 | 3 | 1 | 1 | 1 | 0.023–2.0 | 0.5 | 1.5 | |||||||||
| PT visit | 1 | 1 | 1 | 2 | 4 | 2 | 1 | 0.12–2.0 | 0.75 | 1.0 | ||||||||||||
| Imipenem | MEF AOM | 4 | 2 | 3 | 3 | 5 | 0.023–0.38 | 0.12 | 0.38 | |||||||||||||
| NP/OP AOM | 3 | 3 | 3 | 2 | 5 | 1 | 0.023–0.75 | 0.12 | 0.38 | |||||||||||||
| PT visit | 1 | 4 | 3 | 2 | 1 | 1 | 0.064–0.75 | 0.19 | 0.5 | |||||||||||||
MEF middle ear fluid, nasopharyngeal (NP)/oropharyngeal (OP) samples, PT post-treatment