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


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).


METHODS
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.
Giordano
Philip A
PA
Orlando Regional Medical Center, Department of Emergency Medicine, Orlando, FL 32806, USA.
Elston
Dirk
D
Akinlade
Bolanle K
BK
Weber
Kurt
K
Notario
Gerard F
GF
Busman
Todd A
TA
Cifaldi
Mary
M
Nilius
Angela M
AM
D000038:Abscess / Q000188:drug therapy; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077525:Cefdinir; D002481:Cellulitis / Q000188:drug therapy; D002506:Cephalexin / Q000009:adverse effects / Q000627:therapeutic use*; D002511:Cephalosporins / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017192:Skin Diseases, Bacterial / Q000188:drug therapy*; D013211:Staphylococcus aureus / Q000187:drug effects; D013212:Staphylococcus epidermidis / Q000187:drug effects; D014946:Wound Infection / Q000188:drug therapy
D002511:Cephalosporins; D000077525:Cefdinir; D002506:Cephalexin