Streptococcus pneumoniae Disease
Table 1. Activity of ß-lactam drugs against DRSP causing acute otitis media. Compiled from references 12,13,20,21,37,46,58,59
|
ß-lactam Agent |
Penicillin susceptible strains |
Penicillin intermediate strains |
Penicillin resistant strains |
Peak serum concentration (ug/mL)* |
Peak MEF concentration (ug/mL) |
| |
MIC90 (ug/mL) |
|
|
| Amoxicillin† |
0.03 |
0.1-1 |
2-4 |
3.5-7 |
1-6 |
| Cefuroxime |
0.125 |
1-4 |
4-16 |
2-7 |
1-2 |
| Ceftriaxone (IM) |
0.06 |
1 |
1-4 |
171‡ |
35‡ |
| Cefpodoxime |
0.06 |
1-4 |
4-16 |
1-4 |
0.2-1 |
| Cefprozil |
0.25-1 |
4-8 |
32 |
6-10 |
2 |
| Cefaclor |
1 |
64 |
128 |
7-13 |
0.5-4 |
| Loracarbef |
2 |
64 |
128 |
13-19 |
2-4 |
| Ceftibuten |
0.25-1 |
8-32 |
> 32 |
3-4.6 |
4-9 |
| Cefixime |
0.5 |
16-32 |
64 |
3-4 |
1-2 |
Cefuroxime=cefuroxime axetil. IM=intramuscular. TMP/SMX=trimethoprim/sulfamethoxazole. MEF=middle ear fluid. Penicillin susceptible=MIC <0.1 ug/mL; intermediate=MIC 0.1-1 ug/mL; resistant=MIC>2 ug/mL.
* Obtained with standard dosing
† Applies to amoxicillin-clavulanate as well, at 40 mg/kg/day of the amoxicillin component
‡ Peak concentration after a one-time dose
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Table 2. Activity of erythromycin, trimethoprim/sulfamethoxazole, and clindamycin against DRSP. Compiled from references 12,13,15,58,59
|
Agent |
Penicillin susceptible strains |
Penicillin intermediate strains |
Penicillin resistant strains |
| |
% of isolates resistant |
| TMP/SMX |
6 |
40 |
80 |
| Erythromycin* |
4 |
20 |
49 |
| Clindamycin |
2 |
10 |
15 |
Note: Unlike the graded resistance seen with ß-lactam agents, resistance to these agents tends to be either present or absent, therefore MIC90 values and middle ear fluid concentrations are less useful measures of activity than the proportion of isolates that are resistant to each drug.
TMP/SMX=trimethoprim/sulfamethoxazole
* Applies to clarithromycin and azithromycin as well
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Table 3. Acute otitis media treatment recommendations* for children who have not or have received antimicrobial therapy during the prior month.
|
Antibiotics in prior month |
Day 0 |
Clinically defined treatment failure on day 3 |
Clinically defined treatment failure on day 10 to 28 |
| No |
High dose amoxicillin; usual dose amoxicillin |
High dose amoxicillin-clavulanate; cefuroxime axetil; IM ceftriaxone† |
Same as day 3 |
| Yes |
High dose amoxicillin; high dose amoxicillin-clavulanate; cefuroxime axetil |
IM ceftriaxone;† clindamycin‡
or
Tympanocentesis |
High dose amoxicillin-clavulanate; cefuroxime axetil; IM ceftriaxone†
or
Tympanocentesis |
Note. IM=intramuscular. High dose amoxicillin=80-90 mg/kg/day. High dose amoxicillin-clavulanate=80-90 mg/kg/day of the amoxicillin component, with 6.4 mg/kg/day of clavulanate (requires newer formulations, or combination with amoxicillin).
* Recommended drugs are those for which strong evidence for efficacy currently exists. Other drugs also may prove efficacious. Please see text for details.
† Documented efficacy in AOM treatment failures if three daily doses are used.
‡Clindamycin is not effective against H. influenzae or M. catarrhalis.
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Table 4. Antimicrobial agents useful for AOM treatment which should be included in surveillance for pneumococcal resistance.
|
Agent |
Testing method available |
Notes |
| Penicillin* |
D (oxacillin screen), E, M |
|
| Amoxicillin |
E, M |
Different breakpoints than Penicillin |
| Cefuroxime axetil |
E, M |
|
| Ceftriaxone |
E, M |
|
| Erythromycin* |
D, E, M |
Results apply to azithromycin and clarithromycin |
| TMP/SMX* |
D, E, M |
|
| Clindamycin* |
D, E, M |
|
| Levofloxacin |
D, E, M |
representative fluoroquinolone |
Note. *=included in most current surveillance systems, D=disk diffusion, E=E-test (AB Biodisk), M=microdilution, TMP/SMX=trimethoprim-sulfamethoxazole
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