A case of pachydermodactyly.

Pachydermodactyly (PDD) is a rare, benign form of digital fibromatosis and this is characterized by asymptomatic soft tissue swelling that affects the lateral aspects of the proximal interphalangeal (PIP) joints of the fingers. Although the etiology of PDD is unknown, the possibility of repetitive minor trauma by habitual or compulsive habits of interlacing the fingers or rubbing of the fingers has been suggested as a cause by several authors. We experienced a 14-year-old boy who was diagnosed as having PDD by the clinical manifestations and this was supported by a radiological study and the routine laboratory tests. He also had the habit of repetitively manipulating his hands when feeling emotional distress. PDD sometimes can be misdiagnosed as a rheumatic condition. Although an unusual disorder, PDD should be considered in the differential diagnosis of patients who present with digital bulbous swelling.