Evidence of an association between bullous pemphigoid and psoriasis.

The medical records of 62 consecutive patients with bullous pemphigoid and 62 case-matched leg ulcer controls were examined to determine whether psoriasis and bullous pemphigoid are associated. Psoriasis occurred in seven of the pemphigoid patients (11%) but in none of the controls. The prevalence of psoriasis in the pemphigoid sample was significantly higher than expected (P less than 0.01, Poisson distribution). This difference, together with the clinical course, suggests that there may be an association between pemphigoid and psoriasis.