Webster's New World Medical Dictionary

poly
- Prefix meaning much or many, as in poly-
cystic (characterized by many cysts).
polyarteritis nodosa
An autoimmune disease
that is characterized by spontaneous inflammation
of the arteries (arteritis) and can affect any organ of
the body. Polyarteritis nodosa most commonly
affects muscles, joints, intestines, nerves, kidneys,
and skin. Inflammation of the arteries can lead to
inadequate blood supply and permanent damage to
organs. Typically, polyarteritis nodosa is treated with
medications that suppress the immune system, such
as prednisone and cyclophosphamide.
polyarticular
Involving many joints, as opposed
to monoarticular (affecting just one joint).
polycystic kidney disease
An inherited disor-
der that is characterized by the development of
innumerable cysts in the kidneys that are filled with
fluid and replace much of the mass of the kidneys.
The cysts eventually reduce kidney function, leading
to kidney failure. Abbreviated PKD. PKD can be
diagnosed via ultrasound imaging and via CAT or
MRI scan. Treatment involves managing pain and
treating infections, high blood pressure, and kidney
failure. There are two major forms of PKD—auto-
somal dominant and autosomal recessive—that dif-
fer in many respects. See also 
polycystic kidney
disease, autosomal dominant; polycystic kidney
disease, autosomal recessive.
polycystic kidney disease, adult
See 
polycys-
tic kidney disease, autosomal dominant.
polycystic kidney disease, autosomal domi-
nant
The most common form of polycystic kidney
disease characterized by the progressive develop-
ment of innumerable cysts in the kidneys, causing
hypertension, renal pain, and renal insufficiency
(kidney failure). Other features of the disease can
be cysts in other organs, such as the liver and
pancreas, intracranial aneurysms, dilatation
(widening) and dissection of the aorta, and abnor-
malities in the heart valves. The disease is due to
mutations in the PKD1 gene on chromosome 16 or,
less often, in the PKD2 gene on chromosome 4. Also
known as adult polycystic kidney disease.