ICHTHYOSIS Presented by: Dela Cruz, Beatrice, D. Pangan, May, G. DMD2D
Definition Ichthyosis refers to a relatively uncommon group of skin disorders characterized by the presence of excessive amounts of dry surface scales. It is regarded as a disorder of keratinization or cornification, and it is due to abnormal epidermal differentiation or metabolism. The skins natural shedding process is slowed or inhibited; and in some types, skin cells are produced too rapidly. The disease usually presents at birth, or within the first year, and continues to affect the patient throughout their lifetime.
Signs and Symptoms Depending on the type of gene abnormality that causes ichthyosis, the skin can show different patterns of flaking. Symptoms of all genetic types of ichthyosis are either noticeable at birth or appear during childhood. Symptoms may include: Severe dryness of the skin with thickening and flaking, which may be appear only in limited areas or may involve almost the entire skin surface Mild itching of the skin Body odor, because the spaces under and between skin flakes can harbor collections of bacteria or fungus Wax buildup in the ears, causing hearing difficulties
Signs and Symptoms Symptoms are usually worse in winter months and in dry climates, because warmth and humidity improve these symptoms. Many people who have ichthyosis vulgaris also have allergic problems, such as allergic nasal congestion, asthma or eczema. Xeroderma - occurs most often on the lower legs of middle-aged and elderly adults during cold weather, or on the lower legs of people who bathe too often.
Pathogenesis There are two general types: Inherited ichthyosis (several forms exist) - dryness and scaling of the skin due to hereditary factors Acquired ichthyosis - thickening and scaling of the skin that is not inherited but is associated with certain medical disorders
INHERITED ICHTHYOSIS Depending on the specific type of ichthyosis, the inheritance can be: Autosomal recessive - the altered gene for the disease or trait is located on one of the first 22 pairs of chromosomes (e.g. Lamellar ichthyosis) Autosomal dominant - both males and females are equally likely to have the disease but only one copy of the altered gene is necessary to have the condition. (e.g. Epidermolytic hyperkeratosis) X-linked recessive - much more prevalent in males. It is caused by a deficiency of STS X-linked dominant Sporadic
ACQUIRED ICHTHYOSIS Acquired ichthyosis is relatively rare but may be caused by any of the following: Leprosy (extremely rare in the US) Hypothyroidism Lymphoma ( Hodgkin’s Lymphoma , Adult Non-Hodgkins Lymphoma Sarcoidosis HIV and AIDS A few rare cases of acquired have been attributed to the use of certain drugs: specifically cimetidine, triparanol, dixyrazine, nicotinic acid, and clofazimine In these cases chthyosis is most noticeable on the patients
Diagnosis and Treatment A dermatologist will often make the diagnosis of ichthyosis based on findings from: Skin biopsy or DNA study (from a small blood sample) Prenatal testing (e.g chorionic villus sampling or amniocentesis) Since there is no cure for ichthyosis, treatment consists of managing the symptoms. Most treatment is aimed at restoring the skins moisture and facilitating more aggressive shedding of dead skin cells.
Diagnosis and Treatment Many types of moisturizing ointments, lotions, and creams are used to lessen or alleviate symptoms of ichthyosis. These include petroleum jelly, mineral oil, creams, lotions, and ointments containing vitamin A. For ichthyosis that causes scaling solutions or creams with lactic or salicylic acid or urea may help. In severe cases, drugs are sometimes prescribed, including: Etretinate and isotretinoin -These medications are retinoids, which are derivatives of vitamin A; excess amounts of vitamin A can be harmful. Antibiotics (if the skin becomes infected) Disinfecting soaps (e.g. chlorhexidine)