Dermatology Online Journal

We report a case of pachydermodactyly (PDD). PDD is a benign, asymptomatic soft tissue swelling affecting the skin of the lateral aspects of the proximal interphalangeal joints of the fingers, mostly in young adolescent males. It has often been interpreted as a consequence of tic-like behavior as part of an obsessive-compulsive disorder. Although the diagnosis is essentially clinical, skin biopsy shows compact orthokeratotic hyperkeratosis, increased numbers of collagen fibers and fibroblasts, and no inflammatory changes. A rapid clinical recognition of PDD should avoid many unproductive and expensive diagnostic tests.