Multiple pilomatrixomata and myotonic dystrophy: a familial association.

The association of pilomatrixoma and myotonic dystrophy has been described in the past in 13 publications in the English literature. The association seems to involve the development of pilomatrixomata before signs of myotonic dystrophy. Myotonic dystrophy is the commonest adult dystrophy and is an autosomaldominant disease with a variable phenotypic penetrance. The disease is determined by a genetic locus on chromosome 19q and can be diagnosed using methods of DNA testing. We describe the 25th case of a patient with both conditions together with a review of the literature. To our knowledge, no other patient has had such a large number of histologically proven pilomatrixomata.