Webster's New World Medical Dictionary

idiopathic sclerosing cholangitis
See 
pri-
mary sclerosing cholangitis.
idiopathic torsion dystonia
See 
dystonia,
idiopathic torsion.
IgA
Immunoglobulin A, an antibody.
IgA nephropathy
A chronic disorder caused by
the accumulation of immunoglobulin A deposits
within the filtering units of the kidney, resulting in
the presence of blood and protein in the urine and
swelling in the extremities. The disease progresses
with time and may ultimately lead to renal failure.
High blood pressure is one complication of the dis-
ease. The cause is not fully understood, but genetic
(inherited) factors may be related to the develop-
ment of the condition. Treatment involves medica-
tions and focuses on slowing the progression of the
disease and preventing complications. Also known
as Berger disease.
IgD
Immunoglobulin D, an antibody.
IgE
Immunoglobulin E, an antibody.
IgG
Immunoglobulin G, an antibody.
IgM
Immunoglobulin M, an antibody.
IHSS
Idiopathic hypertrophic subaortic stenosis.
IL
Interleukin.
ileitis, Crohn’s
See 
Crohn’s ileitis.
ileitis, terminal
Inflammation of the end of the
small intestine (terminal ileum) due to Crohn’s dis-
ease. See also 
Crohn’s disease.
ileocolitis, Crohn’s
See 
Crohn’s ileocolitis.
ileum
Part of the small intestine beyond the
jejunum and before the large intestine (colon).
ileus
Obstruction of the intestine due to its being
paralyzed. The paralysis does not need to be com-
plete to cause ileus, but the intestine must be so
inactive that food cannot pass through it, which
leads to blockage of the intestine. Ileus commonly
follows some types of surgery. It can also result from
certain drugs, injuries, and illnesses. Regardless of
the cause, ileus causes constipation and bloating.
When one listens to the abdomen with a stetho-
scope, no bowel sounds are heard because the
bowel is inactive. Also known as paralytic ileus.
ileus, meconium
Obstruction of the intestine
due to overly thick meconium, a dark, sticky sub-
stance that is normally present in the intestine at
birth. Meconium is passed in the feces after birth,
after trypsin and other enzymes from the pancreas
have acted on it. Meconium ileus occurs when the
infant has a deficiency of trypsin and other digestive
enzymes from the pancreas, as in cystic fibrosis.
Treatment is with enemas and can require surgical
procedures.