Given the type of inheritance, mostly men are ill, and most women are asymptomatic carriers of the affected gene. The disease was isolated in a separate form in 1960, occupies the second place in the structure of all types of ichthyosis, second only to ichthyosis vulgaris, and is registered with a frequency of 1:2000-1:6000. Recessive X-linked ichthyosis (RXLI) belongs to the group of mendelian (inherited according to Mendelian laws) keratinization disorders. Life expectancy is normal.Q80.1 X-linked ichthyosis General information The ichthyosis is life-long but hyperkeratosis and scaling may improve with age. RXLI represents a benign form of ichthyosis. during winter, when the ichthyosis is often more severe. For adult patients systemic retinoids are an option, e.
X linked ichthyosis skin#
Treatment consists in hydrating and softening the skin with the use of lubricating bath oils and emollients containing humectants and keratolytics (e. Female patients have rarely been reported. XLRI is transmitted as an X-linked recessive trait: it affects males and is inherited through female carriers. Therefore, RXLI may be detected in utero, when maternal estriol levels are measured for prenatal screening for Down syndrome and other disorders. Maternal urine and serum steroid measurements may show decreased estrogen levels. Differential diagnosisĭifferential diagnosis includes ichthyosis vulgaris, autosomal recessive congenital ichthyosis (ARCI), namely lamellar ichthyosis, syndromic RLXI, or multiple sulfatase deficiency (see these terms). Histology or ultrastructure of the skin is helpful for the differentiation of ichthyosis vulgaris. It is confirmed by biochemical (serum protein electrophoresis, STS activity test of fibroblasts or leukocytes) and molecular/cytogenetic analyses (polymerase chain reaction (PCR), fluorescent in situ hybridization (FISH)). Diagnostic methodsĭiagnosis is based on clinical findings and family history (scaling in male relatives, history of delayed birth). This can be observed in Kallman syndrome, hypergonadotropic hypogonadism, ocular albinism type 1 (see these terms), or hypertrophic pyloric stenosis. There are some much more rare syndromic RXLI cases that are due to contiguous gene deletion affecting neighbouring genes of the STS gene. STS deficiency leads to increased amounts of CSO4 that inhibit epidermal serine proteases, which in turn results in decreased desquamation of corneocytes with retention hyperkeratosis. cholesterol sulfate CSO4, sulfated steroid hormones). STS codes for a lipid hydrolase of the stratum corneum that participates in the regulation of permeability barrier homeostasis and desquamation by catalyzing the hydrolysis of steroid sulfates (e.g. X-linked ichthyosis is an epidermal lipid metabolism anomaly due to inactivating mutations or deletions in the steroid sulfatase STS gene (Xp22.3). Extracutaneous manifestations like testicular maldescent and/or corneal opacities are possible for rare cases, if the ichthyosis is part of a disease syndrome (syndromic RXLI see this term). Delayed birth (insufficient cervical dilatation) may be observed. Scaling improves with age and during summer. Skin's folds, palms and soles, are normally spared. These scales later evolve into grayish or blackish adherent scales that are pronounced on the trunk, the extensor and flexor sites of the extremities, and the neck (giving the ''dirty-neck'' appearance).
Onset may occur within the first days of life with the development of generalized non-erythematous, polygonal, loosely adherent scales. It is the second most common type of ichthyosis with an estimated prevalence of 1 / 2,000 to 1 / 6,000 males.
0 kommentar(er)
