Molecular characterization of Staphylococcus aureus isolates from a 2005 clinical trial of uncomplicated skin and skin structure infections.

A clinical trial of uncomplicated skin and skin structure infections (39 locations in 19 states) observed that community-associated or community-onset methicillin-resistant Staphylococcus aureus (CO-MRSA) represented 23% of all pathogens at baseline culture and 53% of 190 S. aureus isolates. CO-MRSA strains typically were Panton-Valentine leukocidin (PVL) positive (95%), contained staphylococcal cassette chromosome mec type IVa (99%), were USA300 or USA400 clones (92%), and exhibited minimal coresistances (macrolides and/or fluoroquinolones). Clinical results remained identical (89% cures) regardless of the antimicrobial used or CO-MRSA molecular patterns, PVL production, or antimicrobial susceptibility profiles.

Efficacy, tolerability, and parent reported outcomes for cefdinir vs. high-dose amoxicillin/clavulanate oral suspension for acute otitis media in young children.

OBJECTIVES: To compare efficacy, tolerability, and parental satisfaction of cefdinir and high-dose amoxicillin/clavulanate oral suspensions given to young children with non-refractory acute otitis media (AOM) based on clinical endpoints and outcomes measures. RESEARCH DESIGN AND METHODS: This was an investigator-blinded, multicenter study in which 318 children 6 months through 6 years of age with a clinical diagnosis of AOM were randomized to receive 10 days of either cefdinir (14 mg/kg divided BID) or high-dose amoxicillin/clavulanate (90/6.4 mg/kg divided BID). MAIN OUTCOME MEASURES: Investigators evaluated clinical response at an end-of-therapy (EOT) office visit conducted on day 12-15. Outcomes of satisfaction, tolerability, and adherence were also assessed at that visit using an Otitis Parent Questionnaire. RESULTS: The treatment groups were similar at baseline with respect to patient demographics. At the EOT visit, for cefdinir and amoxicillin/clavulanate, respectively, intent-to-treat (ITT) clinical cure rates were 82% (129/158) and 85% (134/158) (p = 0.547; 95% confidence interval [CI] -11.7 to 5.4) and per-protocol cure rates were 82% (123/150) and 90% (129/143) (p = 0.045; 95% CI -16.4 to 0.0). This difference was driven primarily by reduced cefdinir response in patients with recurrent AOM (p = 0.010) and those younger than 24 months (p = 0.039). Comparing cefdinir with amoxicillin/clavulanate, parents more often reported significantly better ease of use (89% vs. 57%; p < 0.0001), better taste (85% vs. 39%; p < 0.0001), and better adherence (at least 95% of doses) (82% vs. 61%; p < 0.0001). Diarrhea/loose stools were more common in the amoxicillin/clavulanate group than in the cefdinir group (28% vs. 18%, respectively; p = 0.0341). One patient in the cefdinir group and eight patients in the amoxicillin/clavulanate group withdrew from the study prematurely due to at least one adverse event (p = 0.0364). Study limitations included assessment of clinical recurrence by telephone call rather than office visit, exclusion of children with refractory AOM, and no assessment of middle ear microbiology. CONCLUSIONS: Among young children with non-refractory AOM, cefdinir was as efficacious as high-dose amoxicillin/clavulanate in the ITT group, but somewhat less effective in per-protocol analysis. From the parental perspective, cefdinir was easier to administer, had a better taste, caused less diarrhea, and resulted in higher treatment adherence than high-dose amoxicillin clavulanate.

Cefdinir vs. cephalexin for mild to moderate uncomplicated skin and skin structure infections in adolescents and adults.

OBJECTIVES: To compare the efficacy and safety of cefdinir to that of cephalexin in adolescents and adults with mild to moderate uncomplicated skin and skin structure infections (USSSI). RESEARCH DESIGN AND METHODS: This was an investigator-blinded, multicenter study in which patients at least 13 years of age with USSSI were randomized to receive 10 days of cefdinir 300 mg twice daily (BID) or cephalexin 250 mg four times daily (QID). Patients were evaluated at baseline, by telephone on Days 3-5, and during office visits on Days 12-14 (end-of-therapy [EOT] visit) and Days 17-24 (test-of-cure [TOC] visit). MAIN OUTCOME MEASURES: Clinical response was evaluated at the TOC visit. Patient reported outcomes, including a usefulness questionnaire, were also assessed. RESULTS: Three hundred and ninety-one patients were treated. The treatment groups were well matched with regard to demographic characteristics and types of infection. Abscess(es) (26%), wound infection (24%), and cellulitis (21%) were the most common infections. At the TOC visit, the clinical cure rate for both treatment groups was 89% (151/170 for cefdinir and 154/174 for cephalexin) in clinically evaluable patients (95% CI for difference in cure rates [-6.7 to 7.3]). In the intent-to-treat analysis, cure rates were 83% for cefdinir vs. 82% for cephalexin. Clinical cure rates for infections caused by methicillin-susceptible (MSSA) and methicillin-resistant (MRSA) Staphylococcus aureus were 93% (37/40) and 92% (35/38) for cefdinir vs. 91% (29/32) and 90% (37/41) for cephalexin (p > 0.999 comparing treatment groups for MSSA; p > 0.999 for MRSA). The usefulness questionnaire demonstrated that cefdinir was more highly rated in the mean composite score (87.4 vs. 83.6, p = 0.04), with the difference primarily due to the respondents' preference for the convenience of taking the study medication (mean score 93.5 vs. 74.1 for cephalexin, p < 0.001). The study had the following limitations: the requirement for culture at baseline likely skewed the enrollment of patients towards those with abscesses; the results of culture in patients with USSSIs are often nonspecific; in some patients entering the study with a diagnosis of cellulitis, the cellulitis was associated with an abscess; and, incision and drainage (I&D), spontaneous drainage, and needle aspiration are likely to have contributed to clinical response for purulent infections, and in particular MRSA-associated infections. Both study drugs were well tolerated. The most common treatment-related adverse events were diarrhea (10% cefdinir, 4% cephalexin, p = 0.017), nausea (3% and 6%, respectively, p = 0.203), and vaginal mycosis (3% and 6% of females, respectively, p = 0.500). CONCLUSIONS: This study demonstrated that empiric coverage of USSSIs with cephalosporin therapy remains an appropriate clinical strategy. MRSA infections responded well in both arms of the study, suggesting that the choice of a cephalosporin did not adversely affect patient outcome. However, cephalosporins do not have accepted, clinically relevant in vitro activity against MRSA. Hence, the clinical response rates seen in this study against MRSA infections must be interpreted with caution. Cefdinir was more highly rated than cephalexin in a composite usefulness assessment.