deformation

deformation A change from the normal size or shape of a structure produced by mechanical forces that distort an otherwise normal structure. Deformations occur most often late in pregnancy and during delivery. For example, a twin pregnancy can cause deformations due to crowding of the twins late in pregnancy. A well-known example of a deformation…

deficiency, zinc

deficiency, zinc A lack of zinc that is associated with short stature, anemia, increased pigmentation of skin, enlarged liver and spleen, impaired gonadal function, impaired wound healing, and immune deficiency. The diagnosis is with an abnormally low blood zinc level. One form of zinc deficiency is the hereditary skin disease acrodermatitis enteropathica. Treatment involves ensuring…

deficiency, selenium

deficiency, selenium Lack of the essential mineral selenium, which can cause Keshan disease, a fatal form of disease of the heart muscle (cardiomyopathy) that was first observed in Keshan province in China and has since been found elsewhere. Treatment involves ensuring intake of the recommended dietary allowance of selenium, currently 70 mg per day for…

deficiency, magnesium

deficiency, magnesium Lack of magnesium, which can occur because of inadequate intake or impaired intestinal absorption of magnesium. Low magnesium levels are often associated with low calcium and potassium levels because these nutrients interact with each other. Magnesium deficiency causes increased irritability of the nervous system, as evidenced by spasms of the hands and feet,…

deficiency, LCHAD

deficiency, LCHAD Deficiency of the enzyme long-chain-3-hydroxyacyl-CoA dehydrogenease (LCHAD), an abnormality of fatty acid metabolism. Acute fatty liver of pregnancy (AFLP) has been found to be associated in some cases with LCHAD deficiency. In such cases, both parents have LCHAD activity at half of normal levels, but the fetus has none. The metabolic disease in…

deficiency, lactase

deficiency, lactase Lack of the enzyme lactase in the small intestine. Lactase is needed to digest lactose, a sugar found in milk and most other dairy products and also used as an ingredient in other foods. Although most people are born with the ability to make adequate amounts of lactase, the production of lactase normally…

deficiency, iron

deficiency, iron An inadequate amount of iron, the most common known form of nutritional disorder in the world. Iron is necessary to make hemoglobin, the molecule in red blood cells that transports oxygen. Iron deficiency results in anemia. The prevalence of iron deficiency is highest among young children and women of childbearing age (particularly pregnant…