Distal interphalangeal joint disease and nail abnormalities.

Psoriatic arthritis has now gained general acceptance as an entity distinct from rheumatoid disease (Garrod and Evans, 1924; McEwen, Ziff, Carmel, DiTata, and Tanner, 1958; Wright, 1961). Distal interphalangeal joint involvement is a prominent feature of psoriatic arthritis (Avila, Pugh, Slocumb, and Winkelmann, 1960; Bauer, Bennett, and Zeller, 1941; Sherman, 1952), but not of rheumatoid arthritis (Thould and Simon, 1966). The nail changes so frequently accompanying the distal interphalangeal joint involvement in psoriatic arthritis are not specific findings (White and Laipply, 1952; Pardo-Castello and Pardo, 1960a) and may be noted in Reiter's syndrome (Weinberger, Ropes, Kulka, and Bauer, 1962) as well as in fungal diseases (Samman, 1965; Pardo-Castello and Pardo, 1960b). A syndrome encompassing features of Reiter's disease and psoriatic arthritis has been observed by a number of investigators (Wright and Reed, 1964; Perry and Mayne, 1965; Khan and Hall, 1965). The entity of psoriatic arthritis without psoriasis or nail changes has been described in the course of family studies (Baker, Golding, and Thompson, 1963). The present report underlines the continuity of disease pattern in patients with nail involvement and distal interphalangeal joint disease, and suggests difficulties in diagnostic categorization. Four selected patients with sero-negative articular disease of 10 or more years duration are described: one with nail and distal interphalangeal joint involvement, but no personal or family history of skin disease of any kind, two with probable "Reiter's disease", one of whom had keratosis blennorrhagica, and one patient with "psoriatic arthritis" or "Reiter's disease".