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Published on: September 3, 2016
Effects of amoxicillin and cefdinir on nasopharyngeal bacterial flora
1Department of Pediatrics, Georgetown University School of Medicine, Washington, DC, USA. ib6@georgetown.edu
Objective:
To compare the effects of cefdinir (14 mg/kg per day) and amoxicillin (90 mg/kg per day) antimicrobial therapy on the nasopharyngeal flora of children with acute otitis media.
Design:
Nasopharyngeal cultures for aerobic and facultative bacteria were obtained before therapy and 2 to 4 days after completion of therapy.
Setting:
Outpatient clinic.
Patients:
Fifty children, aged 7 months to 5 years 4 months.
Main Outcome Measures:
After completion of therapy, 22 (88%) of the 25 patients treated with cefdinir and 16 (64%) of the 25 patients treated with amoxicillin were considered clinically cured (P<.05). A significant reduction in the number of all isolates occurred following therapy in those treated with cefdinir (36 vs 71, P<.01) or with amoxicillin (56 vs 73, P<.05). However, the total number of isolates recovered after therapy was significantly lower in those treated with cefdinir (36) compared with those treated with amoxicillin (56) (P<.01).
Results:
The recovery of potential pathogenic organisms (eg, Streptococcus pneumoniae, Staphylococcus aureus, beta-hemolytic streptococci, Haemophilus species, and Moraxella catarrhalis), as well as penicillin-resistant bacteria, was lower following completion of therapy in the cefdinir group (6 pathogens, including 5 that were penicillin resistant), compared with the amoxicillin group (27 pathogens, including 16 that were penicillin resistant) (P<.01).
Conclusion:
This study illustrates the greater ability of cefdinir compared with amoxicillin to reduce the number of potential nasopharyngeal pathogens as well as penicillin-resistant bacteria in children with acute otitis media.
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