The Bacteriological Study of Impetige Contagiosa / 대한피부과학회지

ABSTRACT

Our present knowledge of impetigo contagiosa extends from its first description as a separate clinical entity by Fox in I864, and the proof of its bacterial etiology by Radcliffe-Crocker in 1881. Both staphylococci and streptococci have been discovered from the lesions, but the relative preponderance of each varies greatly, and reports are contradictory. Seventy-eight patients with impetigo contagiosa were studied bacteriologically in order to ascertain the primary etiologic agent. Also, a susceptibility test (Bauer- Kirby method) was done on the isolated organisms with 7 antibiotics which are used frequently in the clinical field. Specimens obtained from the skin lesions were cultured and organisms were isolated. They were identified by various biochemical and serological tests. A DN ase test, a carbohydrate fermentation test, and a coagulase test were done for the isolated staphylococci. A bacitracin disc method and a precipitin test(Lancefield method) were done for the isolated B-hemolytic streptococci. The results were as follows Fifty-six cases(71.8%) were infected by staphylococcus only. Twenty cases(25.6%) were infected by a mixture of staphylococcus and p-hemo- lytic streptococcus. Only 2 cases(2.6%) were infected by B-hemolytic streptococcus alone. All 76 strains of staphylococci were identified as coagulase positive staphylococci. Among the 22 strains of B-hemolytic streptococci, 15 strains were identified as group A and remaining 7 strains were identified as group B. Coagulnse negative sta,phylococcus was not found. In the susceptibility test to 7 antibiotics, staphylococci showed susceptibility to lincomycin, erythromycin, cloxacillin, and chloramphenicol, and resistance to tetra-cycline, penicillin, and ampicillin. Streptococci showed susc.ptibility to all of the above antibiotics except tetracycline. From the results of this experiment, it was concluded that the primary etiologic agent of impetigo contagiosa was coagulase positive staphylococcus and streptococcus for the most part can be considered as a secondarily infecting agent. Coagulase negative staphylococcus apparently is not implicated as an etiologic agent of impetigo contagiosa. The results of the antibiotic susceptibility tests would seem to indicate that the use of such antibiotics as tetracycline, penicillin, and ampicillin is not indicated in the treatment of impetigo contagiosa.