Webster's New World Medical Dictionary

deficiency, long-chain-3-hydroxyacyl-CoA
dehydrogenease
See 
deficiency, LCHAD.
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 cal-
cium 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, mus-
cular twitching and cramps, spasms of the larynx,
and other symptoms. Treatment involves ensuring
intake and absorption of the recommended dietary
allowances of magnesium, currently 420 mg per day
for men and 320 mg per day for women. One
should not take more than 350 mg per day in sup-
plement form, however.
deficiency, niacin
See 
pellagra.
deficiency, protein C
See 
protein C deficiency.
deficiency, selenium
Lack of the essential min-
eral selenium, which can cause Keshan disease, a
fatal form of disease of the heart muscle (cardiomy-
opathy) that was first observed in Keshan province in
China and has since been found elsewhere.
Treatment involves ensuring intake of the recom-
mended dietary allowance of selenium, currently 70
mg per day for men and 55 mg per day for women.
Food sources of selenium include seafood; some
meats, such as kidney and liver; and some grains and
seeds.
deficiency, UDP-glucuronosyltransferase
See
Gilbert syndrome.
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 enteropath-
ica. Treatment involves ensuring intake of the rec-
ommended dietary allowance of zinc, currently
recommended 12 mg per day for women and 10 mg
per day for men. Food sources of zinc include meat,
eggs, seafood, nuts, and cereals. Longstanding zinc
deficiency can lead to chronic diarrhea and inflam-
mation of the skin (dermatitis). See also 
acroder-
matitis enteropathica.
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 defor-
mation is molding of the head of a baby born by