Systemic epidermal nevus with involvement of the oral mucosa due to FGFR3 mutation
1 Department of Dermatology and Allergy Centre, Odense University Hospital, 5000 Odense, Denmark
2 Department of Clinical Genetics, Odense University Hospital, 5000 Odense, Denmark
3 Department of Clinical Pathology, Odense University Hospital, 5000 Odense, Denmark
4 Institute of Human Genetics, University of Regensburg, 93042 Regensburg, Germany
5 Department of Dermatology, University of Regensburg, 93042 Regensburg, Germany
BMC Medical Genetics 2011, 12:79 doi:10.1186/1471-2350-12-79Published: 5 June 2011
Epidermal nevi (EN) represent benign congenital skin lesions following the lines of Blaschko. They result from genetic mosaicism, and activating FGFR3 and PIK3CA mutations have been implicated.
We report a female patient with a systemic keratinocytic nevus also involving the oral mucosa. Molecular genetic analysis revealed a mosaicism of the FGFR3 hotspot mutation R248C in the EN lesions of the skin and of the oral mucosa. The detection of the R248C mutation in a proportion of blood leukocytes and a slight scoliosis suggest an EN syndrome.
Our results show that activating FGFR3 mutations can also affect the oral mucosa and that extracutaneous manifestations of EN syndrome can be subtle. We highlight the theoretical risk of the patient having an offspring with thanatophoric dysplasia as gonadal mosaicism for the R248C mutation cannot be excluded.