Faecal incontinence due to atrophy of the anal sphincter in myotonic dystrophy: a case report.

Myotonic dystrophy or Steinert disease is an autosomal dominant multisystemic disorder with variable penetrance. The genetic defect is an amplified trinucleotide repeat in the 3-prime untranslated region of a proteinkinase gene on chromosome 19. Severity of symptoms increases with the number of repeats. Patients with myotonic dystrophy often present with gastrointestinal motility problems, such as intermittent diarrhoea, constipation, and also faecal incontinence. The underlying physiopathological mechanism of faecal incontinence differs from classic soiling due to faecal retention. We present a girl with congenital myotonic dystrophy and faecal incontinence due to anal sphincter atrophy; and give an overview of present knowledge on the pathophysiology of gastrointestinal problems associated with myotonic dystrophy.