Deposits of complement and immunoglobulins in dermal and synovial vessels in psoriasis.

Deposits of complement C3 and/or immunoglobulin were found in the vessel walls and/or at the dermal-epidermal junction in skin lesions of all of 11 patients with psoriatic arthritis and guttate psoriasis. Similar deposits were seen in 6 out of 15 patients with psoriasis vulgaris. Synovial tissue available from 2 patients revealed deposits in the vessel walls.