title: Marked increase in the frequency of psoriatic arthritis in psoriasis patients with HLA-DR+ keratinocytes.
abstract: Immunocytochemical studies with a monoclonal anti-HLA-DR antibody were performed on skin sections and keratinocyte (KTC) suspensions obtained from suction blisters of active psoriatic plaques. HLA-DR+ KTCs were found in the plaques of 23 of 38 patients with active psoriasis. Of these 23, 16 had clinical findings typical of psoriatic arthritis (PA); none of the 15 patients who lacked HLA-DR+ KTCs had PA. Although KTC HLA-DR expression was more prevalent in patients with severe skin disease, 7 of the 23 patients with HLA-DR+ KTCs in active psoriatic plaques had mild skin disease; 4 of these 7 had PA. Nail pitting or duration of skin disease did not account for increased incidence of PA in patients with HLA-DR+ KTCs. All psoriasis patients with arthritis received nonsteroidal antiinflammatory drug therapy; 14 received additional therapy directed primarily to the cutaneous manifestations of psoriasis. Nine of these noted arthritis improvement with concurrent skin response; however, in 5 patients, arthritis activity increased, despite improvement of the cutaneous disease. Two other patients, treated with methotrexate, also had concurrent skin and joint improvement. These data suggest that psoriasis patients with HLA-DR+ KTCs are at increased risk for the development of associated arthritis.
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D001168:Arthritis / Q000150:complications / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D004817:Epidermis / Q000473:pathology*; D006681:HLA-D Antigens / Q000032:analysis*; D006684:HLA-DR Antigens / Q000032:analysis*; D006651:Histocytochemistry; D006801:Humans; D007120:Immunochemistry; D007633:Keratins; D011565:Psoriasis / Q000150:complications / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D006681:HLA-D Antigens; D006684:HLA-DR Antigens; D007633:Keratins