Neurofibromatosis 1: clinical review and exceptions to the rules.

Neurofibromatosis 1 is an autosomal dominant, multisystem disorder with myriad clinical manifestations. Between 1991 and 1998, 495 adults and children were diagnosed with neurofibromatosis 1 at a specialized neurogenetics clinic in Sydney, Australia. This review establishes the prevalence of the clinical manifestations of neurofibromatosis 1 in these patients and provides guidelines for assessment and management. In addition, we review in detail patients who had unusual presentations and who represent important "exceptions to the rules" of clinical practice.