Inherited ichthyoses are a group of genetic disorders characterized by dry skin, hyperkeratosis, and increased scale desquamation, often associated with erythroderma. The clinical manifestations are due to a series of mutations of genes involved in the development of the stratum corneum and skin barrier formation. The group consists of phenotypic expressions limited only in the skin and its appendages and others with additional extracutaneous involvement. The incidence of ichthyotic conditions in pigmented and black skin ethnic populations is not known. In two reports from the Eastern Province of Saudi Arabia, the incidence of hereditary ichtyosis and non-bullous congenital ichthyosiform erythroderma has been assessed, respectively, 7 per 1000 and 2 per 1000 new patients. These relatively high rates may be attributed to high consanguinity in countries of the Middle East [1, 2]. The commonest type of hereditary ichthyosis was ichthyosis vulgaris followed by non-bullous ichthyosiform erythroderma; 90% of the patients in this group were born with collodion membranes. Also in populations in East Africa, ichthyoses are not rarely seen.
- 14.Glick JB, Craiglow BG, Choate KA, et al. Improved management of harlequin ichthyosis with advances in neonatal intensive care. Pediatrics. 2017;139(1). https://doi.org/10.1542/peds.2016-1003.