A Study on the Role of Bacteria in the Pathogenesis of Confluent and Reticulated Papillomatosis / 대한피부과학회지

ABSTRACT

BACKGROUND: The pathogenesis of confluent and reticulated papillomatosis(CRP) is still unknown, although many theories have been suggested. It is stressed that abnormal host response to colonization of pityrosporum orbiculare might play a role in the pathogenesis of CRP, but is not completely understood. Frequently, we have observed bacterial colonies in the stratum corneum and, especially, within the hair follicles from biopsy specimens of patients with CRP. In addition, successful treatment for CRP with minocycline, a derivative of tetracyclines, has been reported continuously. OBJECTIVE: The purpose of this study was to document the possible association of bacterial factors in the pathogenesis of CRP and to elucidate the effectiveness of minocycline. METHODS: We performed Brown and Brenn gram staining in 12 biopsy specimens, bacterial cultures, identification of microorganisms and antibiotics sensitivity testing including minocycline. We administered oral minocycline with an initial dose of 100mg per day for 1 to 3 months and a maintenance dose 50mg per day for I to 2 months, then evaluated the response of treatment. RESULTS: 1. On Brown and Brenn staining, the gram positive bacterial colonies that stained dark bluish or nearly black were observed within the infundibulum of hair follicles in 10 out of 12 biopsy specimens(83.3%) and on the keratotic invagination of stratum corneum in 11 out of 12 biopsy specimens(91.7%). 2. Histological features of regions where bacterial colonies were observed showed, hyperkeratosis and keratotic invagination on the stratum corneum in all cases. Hyperkeratosis(66.7%), parakeratosis(16.7%), inflammatory cell infiltration(25.0%), perifollicular fibrosis(33.3%), and abnormal keratin in sebaceous ducts(50.0%) were shown in hair follicles. 3. In anaerobic cultures, no bacteria was grown. In aerobic cultures, staphylococcus species were identified in 6 cases, streptococcus viridans in one case, sternotrophomonas maltophilia in one case. In the susceptibiliity test, minocycline was sensitive in 7 from 8 cases. 4. The therapeutic response to minocycline was observed within one month in all cases, and the time to clear the lesions was 1/2 month in 2 cases, 1 month in 4 cases, 2 months in 5 cases, 3 months in one case, respectively. CONCLUSION: Form these results, we suggest that bacterial factors may play an important role in the pathogenesis of CRP and that the action mechanism of minocycline in the treatment of CRP may be due to antibacterial effects.