Synopsis
Use skin, hair, nail and dental patterns to recognise inherited and mosaic disorders, detect urgent neurological and ocular disease, choose phenotype-led genomic testing and coordinate lifelong multi-organ surveillance.
- A genodermatosis may be inherited or post-zygotic mosaic; distribution along Blaschko lines or a body segment can be as informative as family history.
- Neurofibromatosis type 1 evolves with age: café-au-lait macules appear early, axillary or groin freckling later, then neurofibromas, with eye, bone, blood-pressure and developmental risks.
- Tuberous sclerosis clues include three or more hypomelanotic macules at least 5 mm, facial angiofibromas, shagreen patch and ungual fibromas alongside seizures and renal, cardiac or lung disease.
- Use a Wood lamp to reveal subtle hypomelanotic macules, especially in light skin, but record shape, size and number rather than treating fluorescence as a diagnosis.
- A capillary malformation over the forehead or upper eyelid can signal Sturge–Weber syndrome and glaucoma; early ophthalmology and neurological assessment is more urgent than cosmetic planning.
- Incontinentia pigmenti usually follows Blaschko lines through vesicular, verrucous and hyperpigmented stages and can associate with retinal, dental and neurological abnormalities.
- Recurrent blistering after minimal trauma suggests epidermolysis bullosa; wound care, pain, nutrition, infection prevention and avoidance of adhesive injury begin before subtype confirmation.
- Congenital scaling, hair-shaft abnormality, missing or conical teeth, reduced sweating or extreme photosensitivity can reveal ichthyosis, ectodermal dysplasia or DNA-repair disease.
- Choose genomic testing from a defined phenotype and discuss uncertain findings, mosaicism, familial implications and future autonomy before sampling.
- A normal early scan or examination does not end surveillance because many neurocutaneous manifestations emerge at predictable ages.
Key red flags
New seizures, developmental regression, persistent headache or vomiting, focal neurology, sudden visual symptoms, painful or rapidly enlarging nerve tumour, hypertension, haematuria, respiratory decline, extensive blistering or infection, inability to sweat with hyperthermia, or an evolving tumour within a mosaic lesion requires urgent syndrome-specific assessment.
A painful rapidly enlarging hard plexiform-neurofibroma area, new weakness, sphincter symptom or persistent night pain raises malignant or compressive transformation risk.
Investigation priorities
Define diagnostic criteria, mosaic distribution and inheritance probability before testing.
Management branches
Multiple congenital, patterned or syndromic skin signs are identified.
- Record lesion type, size, count, distribution and age of appearance and examine hair, nails, teeth, eyes, blood pressure, growth, development and neurology.
- Construct a three-generation pedigree and identify the organ complication that would cause most immediate harm, arranging its specialist assessment first.
- Refer to clinical genetics or the appropriate neurocutaneous service with photographs, measurements and a focused diagnostic question rather than an unfiltered feature list.