Incontinentia pigmenti (IP) should be suspected in individuals with characteristic clinical findings of the skin, teeth, hair, nails, eyes, CNS, and family history as detailed below.
The major criteria (skin lesions that occur in stages from infancy to adulthood) for IP clinical diagnosis are:
- Erythema followed by blisters (vesicles) anywhere on the body except the face, usually in a linear distribution (first weeks of life to age 24 months).
- Verrucous lesions that respect Blaschko’s lines, occurring mainly on the limbs; stage II (first weeks of life to 24 months).
- Hyperpigmented streaks and whorls that respect Blaschko’s lines, occurring mainly on the trunk and fading in adolescence (age 4 months to 16 years).
- Pale, hairless, atrophic linear streaks or patches (adolescence through adulthood).
Minor criteria:
- Teeth: Hypodontia or anodontia (partial or complete absence of teeth), microdontia (small teeth), abnormally shaped teeth.
- Hair:. Alopecia, woolly hair (lusterless, wiry, coarse).
- Nails: Mild ridging or pitting; onychogryposis (hypertrophied, curved nails).
- Retina: Peripheral neovascularization.
- CNS: Seizures, intellectual disability, learning disabilities, brain anomaly, spastic paresis (30% of IP).
- Family history consistent with X-linked inheritance or a history of multiple miscarriages.
Identification of eosinophilic infiltration and/or extracellular melanin granules on histologic examination of a skin biopsy may be more helpful in males.