This rare genetic disorder affects several parts of the body such as the skin, eyes, teeth and the central nervous system. In around 90% of the cases, the skin lesions are evident at the birth of the infant or develop within a few weeks of their life.
Causes
Incontinentia pigmenti develops as the result of the mutation in the gene IKBKG. This gene is necessary for the production of a protein that regulates the nuclear factor-kappa-B that protects the cells from self-destructing. When the genetic material is deleted, this affects the normal production or results in the nonfunctional IKBKG proteins. As the result, the cells are very sensitive to certain signals that trigger their destruction. Hence, the abnormal cell death causes the symptoms that are associated with this condition. This is inherited in an X-linked dominant pattern meaning the defective gene is located in one of the sex chromosome (X chromosome). Males only have a single X chromosome, unlike the females who carry two X chromosomes. Rarely, this can also develop as the result of a spontaneous mutation.
Symptoms
The initial features of this disorder include the progressive skin rashes. The skin problems begin as the blistering rashes followed with the wart-like skin growths. The minor problem of the hair is evident such as the coarse, lusterless hair in about 50% of the women and can be caused by the scarring from the rash. In around 80% of the cases, the abnormalities of the teeth are evident such as delayed primary teeth eruption, missing teeth or unusual structure of the teeth. The nails are pitted, thickened or disrupted completely and can include growth under the nails or blistering skin lesions. Some of the eye problems include near or far-sightedness and the abnormal blood vessel growth within the eye (the retina). In some of the cases, severe neurological complications can also develop such as seizures, paralysis, developmental problems and mental retardation.
Diagnosis
The diagnosis is based on the clinical evaluation, the individual’s medical history, family history and in identifying the features that are characteristic of this condition. The skin biopsy that detects the ‘loose’ melanin can confirm the diagnosis. The molecular genetic testing can identify the gene that is responsible for causing this disorder.
Treatment
The skin abnormalities can disappear on its own by the adulthood without the need for treatment. The eye condition can be treated with cryotherapy and laser photocoagulation to prevent the retinal detachment. The dental problems can be rectified with dental implants in childhood. In the case the dental abnormalities affect the speech of the individual, they may require the assistance from the speech pathologist. The hair condition is usually not severe but may benefit from consultation with the dermatologist depending on the case. Various medications can treat the neurological symptoms such as the mild paralysis and seizures.
References
https://rarediseases.org/rare-diseases/incontinentia-pigmenti/
http://www.dermnetnz.org/topics/incontinentia-pigmenti/
https://ghr.nlm.nih.gov/condition/inscontinentia-pigmenti#inheritance
http://www.ipif.org/treatment.html
