Relationship of Staphylococcal Aureus Colonization with Severity of Psoriasis Vulgaris Disease According to PASI Score

colonized by staphylococcus aureus were reported in more than 50% of psoriatic lesions. Due to role of epidermal barrier dysfunction on colonization and on the other hands staphylococcal super antigen effect on flare up of disease, this study was conducted to evaluate relationship of staphylococcal aureus colonization with severity of psoriasis disease according to PASI Score. In a descriptive analytic study, 42 psoriasis new cases that had not received any topical or systematic medication for disease underwent study. Necessary demographic and clinical data were collected and PASI score for severity of disease according to erythema, infiltration, desquamation and area was calculated. Skin lesions samples were taken by a swab and sent to the laboratory for culture. Data analysis was done by SPSS ver. 13 using T test. lesions of 19 cases (45.2%) were colonized with staphylococcal aureus. Mean of PASI score in positive culture group was 16.07± 3.6 in comparison to negative culture group as 12.43± 3.67 that this difference was significant (P=0.001). There was not any significant difference between duration of disease between positive and negative culture groups (7.11±4.98vs. 6.39±5.25 years). This study showed a significant difference between PASI Score among negative and positive culture groups that this difference may be due to the staphylococcal super antigen effect on psoriasis lesions.