Incontinentia Pigmenti Health Article

Signs and symptoms

Familial, male-lethal (type II) IP is characterized by progressive rashes of the skin. These have been classified into four stages: the red (erythematic) and blister-like (vesicular) stage; the wart-like (verrucous) stage; the darkened skin (hyperpigmented) stage; and the scarred (atrophic) stage.

The first, or erythematic vesicular, stage consists of patches of red skin containing blisters and/or boils. This condition usually appears in affected individuals at or near birth and is generally localized to the scalp, the arms, and the legs. This stage generally lasts from a few weeks to a few months and may recur within the first few months of life. It rarely recurs after the age of 6 months. This condition is often misdiagnosed as chicken pox, herpes, impetigo, or scabies. Each of these alternative diseases is potentially life-threatening in an infant, so most IP affected infants are treated for one of these diseases before the appropriate diagnosis of incontinentia pigmenti can be made.

The second, or verrucous, stage of IP is characterized by skin lesions that look like adolescent acne (pustules). Upon healing, these pustules generally leave darkened skin. This stage almost exclusively affects the arms and legs, but it may be observed elsewhere. The verrucous stage may occur at birth, which may indicate that the erythematic vesicular stage occurred prior to birth. But, more generally, the second stage of IP skin disorder is observed after the first stage has completed. The verrucous stage tends to persist for months. Rarely it may last for an entire year.

The third, or hyperpigmented, stage is characterized by "marbled skin," in which darkened areas of skin seem to make swirling patterns across the normal and less pigmented skin. This third stage generally occurs between six and 12 months of life. In 5-10% of affected individuals, this third stage is present at birth. These areas of hyperpigmentation tend to fade with age such that they are barely visible in adults affected with type II IP.

Areas of scarred skin caused by the first two stages characterize the fourth, or atrophic, stage. These scars are often noticeable before the third stage has begun to fade. Adolescents and adults affected with type II IP will generally have pale, hairless patches or streaks, most visibly on the scalp or calves, that are associated with this fourth stage. In many adults affected with IP, the skin abnormalities may have faded to such a significant degree that they are no longer noticeable to the casual observer. Many type II IP affected individuals have a loss or lack of hair on the crown of the head (alopecia). This is suspected to be caused by the underlying skin atrophies of IP.

More than 80% of individuals affected with type II IP have abnormalities of the teeth including missing teeth, late eruption of both the baby teeth and the adult teeth, unusually pegged or cone-shaped teeth, and deficiencies in the enamel. A smaller percentage (approximately 40%) of affected individuals have irregular formations of the finger and toe nails including missing nails, thickened nails, and ridged or pitted nails. In a small number of cases, the skin lesions associated with the first two stages of skin abnormalities may be present underneath a nail. In these cases, it is possible for this lesion to develop into a benign tumor that may cause abnormal bone development in the affected finger or toe.

Approximately 30% of all individuals affected with IP experience visual problems. Less than ten percent of type II IP affected individuals have vision problems related to an abnormal growth of blood vessels in the retina which may, if untreated, lead to a detachment of the retina possibly resulting in blindness. These symptoms generally are seen before the affected individual reaches the age of five. Other vision problems that have been observed in type II IP affected individuals include crossed eyes or "wall eyes" resulting from an improper alignment of the eyes (strabismus); partial or complete opaqueness in one or both lens (cataract); and, occasionally abnormally small eyes (microphthalmia). Because of these vision problems, some individuals affected with IP are blind at birth or will go blind if corrective treatment is not sought.

The incidence of breast development anomalies in type II IP affected girls is quite common. It is estimated to be more than ten times that of the general population. These anomalies range from the presence of an extra nipple to the complete absence of breasts.

Approximately 25% of all IP affected individuals have disorders of the central nervous system. These include mental retardation, slow motor development, epilepsy, an abnormally small brain (microcephaly) and increased muscle tone in both legs (spastic diplegia) or in all four limbs (spastic tetraplegia) similar to that seen in the classic case of cerebral palsy.