Twin Sisters with an Odd, Progressive Rash

Twin sisters visiting from another city for a well-child visit.

Initial history reveals nothing out of the ordinary in the perinatal or early developmental period.

Mother describes a rash that appeared on both girls shortly after birth--linear, inflammatory vesicles on their trunks and extremities.

Vesicles were unroofed, stained and showed eosinophilia. Initial diagnosis was made and close follow-up initiated.

Vesicular rash followed in 3-4 weeks verrucous lesions on extremities and back. Now seen are "Chinese" forms that are smooth/macular and slate brown to bluish-grey in color.

Twins showing lesions that are smooth, macular, slate-brown-bluish grey.

Hyperpigmented whorls on chest and abdomen of one twin sister.

Hyperpigmented whorls on side of one twin sister.

Swirled lesion on upper leg of one twin sister.

Diffuse swirled lesion covers child's lower abdomen, anterior thorax, and extends to groin and upper legs.

Diffuse swirled lesion on one twin's axilla and lateral thorax.

Differential diagnosis, partial: Bullous impetigo, herpes simplex, varicella, epidermolysis bullosa, mastocytosis, ichthyosiform erythroderma, incontinentia pigmenti, congenital bullous pemphigoid, linear IgA bullous disease of childhood.

Lesions have progressed through 3 distinct stages: stage 1. vesicular; stage 2.verrucous; 3. smooth, hyperpigmented.

Lesions have progressed through 3 distinct stages: stage 1. vesicular; stage 2.verrucous; 3. smooth, hyperpigmented.

Diagnosis: incontinentia pigmenti. Rare, X-linked dominant neurocutaneous syndrome with cutaneous, neurologic, ophthalmologic, and dental manifestations.

Incontinetia pigmenti: male lethal syndrome; gene normally codes for the NEMO or NF-kappaB protein.

Without family history, diagnosis requires presence of one major criterion: typical neonatal vesicular rash with eosinophilia, typical blaschkoid hyperpigmentation on trunk, linear, atrophic hairless lesions

If there is a definitive family history, finding of any single major criterion strongly supports the diagnosis of incontinentia pigmenti.

Spectrum of anomalies include dental, orthopedic, ophthalmologic, neurologic, neurodevelopmental.

In absence of neonatal neuropathology, long-term prognosis considered normal, including intelligence.