Background: Impetigo is a common infectious skin disease and most
commonly occurs in children. Etiologic agents are Staphylococcus aureus
or Beta-heamolytic Streptococcus group A or combination of these
organisms. Adequacy of treatment is related on sensitivity of bacteria
to common prescribed antibiotics.Methods: Study of the frequency of
bacterial culture results from lesions and antibiograms for four
systemic antibiotics cephalexin, erythromycin, cloxacillin and
penicillin were assayed. Impetigo cases admitted to the dermatology
clinic of Ghaem hospital in Mashhad for one year beginning from June
2001, were studied. These patients had no history of systemic or
topical antimicrobial agents application. Results of antibiograms
obtained from culture of skin lesions were analyzed with Chi-Square
test.Findings: Twenty two (88%) patients were younger than 20 years.
Twenty one cases (84%) had non bullous impetigo. In 17 (68%) cases
lesions were localized on the face. Because of secondary contamination
in 3 cases, statistical analysis was performed on 22 cases. The most
common bacteria (95.5%) was Staphylococcus aureus. Antibiograms of
S.aureus showed complete sensitivity to cephalxin in 85.3%,
erythromycin in 63.6%, cloxacillin in 40.9%, and penicillin in 13.6% of
cases. Conclusions: Staphylococcus aureus was the most common organism
in 95.5% of cases and cephalexin was the first choice oral antibiotic
followed by erythromycin