Von recklinghausens disease: a series of four cases with variable expression.

Though neurofibromatosis type I (NFI) is a fairly common condition, it has a variable expressivity and penetrance. Here we present a series of cases with striking differences in the presentation especially in the oral cavity. NFI, also known as von Recklinghausen's neurofibromatosis, is an autosomal dominantly inherited neurogenetic disorder affecting 1:3000 newborn (Bongiorno et al., Oral Dis 12:125-129, 2006). About 50 % of NFI patients have no family history of the disease. There is no prevalence for gender or race in NFI. Expressivity in NFI is tremendously variable, but subtle phenotypic patterns may exist within subgroups of affected patients. Furthermore, 50 % of cases are sporadic and arise from germ cell mutation (Bongiorno et al., Oral Dis 12:125-129, 2006). The precise constellation of findings in any one individual is extremely variable, both within a family and between different families (Batsakis, Tumors of the head and neck: clinical and pathological considerations, 2nd edn. Williams and Wilkins, Baltimore, pp 313-333, 1979). Only 4-7 % of patients affected by neurofibromatosis exhibit oral manifestations (Güneri et al., Turk J Pediatr 48(2):155-158, 2006).