The coexistence of systemic lupus erythematosus and psoriasis.

Systemic and discoid lupus erythematosus (LE) have both been reported in association with psoriasis. Four additional patients who had systemic LE are reported. All of them had a high titer of antinuclear antibodies (ANAs) and were SS-A(Ro)-negative. Only one patient exhibited photosensitivity. SS-A(Ro) antibodies do not appear to be specific markers for the coexistence of LE and psoriasis, and screening for them in all psoriatics prior to ultraviolet B phototherapy is not recommended. Pitfalls in the management of patients with systemic LE and psoriasis are discussed.