title: Mosaic NRAS Q61R mutation in a child with giant congenital melanocytic naevus, epidermal naevus syndrome and hypophosphataemic rickets.
abstract: The association of hypophosphataemic rickets with verrucous epidermal naevus (EN) and elevated fibroblast growth factor 23 levels is known as cutaneous-skeletal hypophosphataemia syndrome (CSHS), and can be caused by somatic activating mutations in RAS genes. We report a unique patient with CSHS associated with giant congenital melanocytic naevus (CMN), neurocutaneous melanosis and EN syndrome, manifesting as facial linear sebaceous naevus, developmental delay and ocular dermoids. An activating mutation Q61R in the NRAS gene was found in affected skin and ocular tissue but not blood, implying that the disparate manifestations are due to a multilineage activating mutation (mosaic RASopathy). We speculate on the apparently rare association of CSHS with CMN compared with EN. We also report the favourable outcome of this patient at the age of 8 years after extensive neonatal curettage of the giant CMN and use of vitamin D and phosphate supplementation.
authors.affiliation: Birmingham Skin Centre, Sandwell and West Birmingham Hospitals NHS Trust, Birmingham, UK.|Department of Paediatric Dermatology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK.
authors.forename: R
authors.initials: R
authors.lastname: Ramesh
authors.affiliation: Department of Paediatric Endocrinology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK.
authors.forename: N
authors.initials: N
authors.lastname: Shaw
authors.affiliation: Department of Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK.
authors.forename: E K
authors.initials: EK
authors.lastname: Miles
authors.affiliation: Department of Plastic Surgery, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK.
authors.forename: B
authors.initials: B
authors.lastname: Richard
authors.affiliation: Department of Histopathology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK.
authors.forename: I
authors.initials: I
authors.lastname: Colmenero
authors.affiliation: Department of Paediatric Dermatology, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK.|University of Birmingham, Birmingham, UK.
authors.forename: C
authors.initials: C
authors.lastname: Moss
mesh_terms: D002675:Child, Preschool; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000235:genetics*; D020558:GTP Phosphohydrolases / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D009030:Mosaicism; D009154:Mutation; D009506:Nevus / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism; D009508:Nevus, Pigmented / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism; D063730:Rickets, Hypophosphatemic / Q000151:congenital / Q000175:diagnosis / Q000235:genetics*; D012867:Skin / Q000473:pathology*; D012878:Skin Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism
chemical_list: D004273:DNA, Neoplasm; D008565:Membrane Proteins; D020558:GTP Phosphohydrolases; C579846:NRAS protein, human