This is an inherited condition that is characterized by the scaling of the skin that is evident shortly after the birth. Although some of the cases may not present the skin problem immediately, they will show signs by the age of 1 year. This type of Ichthyosis is estimated to affect around 1 in 2,000 to 4,000 male infants, although the mild cases may remain undiagnosed.
Causes
This disorder develops as the result of the genetic mutation that causes the deficiency of the enzyme known as steroid sulphatase essential for the skin. As the result of this deficiency, the skin is not able to shed normally and appears to be dry and scaly. The genetic mutation is present in one of the sex chromosomes known as the X-chromosome. As men inherit only a single copy of the X chromosome they usually are affected with this disorder than the females who carry two X chromosomes. The females are often the carriers of the X-linked condition but don’t necessarily present any symptoms. The genetic deletions in the neighboring genes can also occur causing the contiguous gene defect. Hence, the individuals affected with this condition should also be evaluated with kallmann syndrome, short stature and mental retardation.
Symptoms
Among the affected individuals, the skin cells are produced normally but do not shed as quickly as they are supposed to and as the result, the scales build-up. The scales appear to be dark usually covering a part of the body resembling fish scales that gives the ‘dirty’ appearance. Commonly, the parts of the body that appears to be unaffected include the face, palms of the feet, soles of the feet and in some cases it also includes the neck. Although this is a lifelong condition, around 80% of the cases have experienced improvement with ageing.
Diagnosis
The diagnosis of Itchthyosis X-linked is based on the evaluation of the individual’s medical history, family history and with the identification of the features that are characteristic of this condition. This disorder can be prenatally diagnosed with the aminocentesis or chorionic villus sampling. The reduced level of the maternal serum or urine estriol and dehydroepiandrosterone is also an indication of the X-linked Itchthyosis. The skin biopsy may be helpful with the diagnosis of this disorder and includes the hyperkeratosis and hypergranulosis.
Treatment
There is no cure for this condition and the treatment is based on relieving the symptoms. This includes the treatment with topical creams such as moisturizers and bath oils. Depending on the severity of the condition, the affected individual may benefit from the more greasy lotions in the winter when the disorder appears to be severe. In some of the cases, the genetic counseling may be beneficial for the affected individuals and their family.
References
https://rarediseases.org/rare-diseases/ichthyosis-x-linked/
http://www.firstskinfoundation.org/types-of-ichthyosis/x-linked-ichthyosis
http://www.dermnetnz.org/topics/recessive-x-linked-ichthyosis/
