Webster's New World Medical Dictionary

Koch postulates
A set of criteria for judging
whether a given microorganism is the cause of a
given disease.
Kok disease
See 
hyperexplexia.
Koplik spots
Little spots inside the mouth that
are highly characteristic of the early phase of
measles (rubeola). The spots look like tiny grains of
white sand, each surrounded by a red ring. They are
often found on the inside of the cheek, opposite the
first and second upper molars. See also 
measles.
Kostmann disease
See 
severe congenital
neutropenia.
Krabbe disease
A progressive degenerative disor-
der of the nervous system that involves the destruc-
tion of myelin, a fatty material that surrounds and
insulates nerves. Most patients have the infantile form
of Krabbe disease. During the first few months of life,
they seem normal, but before 6 months of age, the
signs of extreme irritability, spasticity, and develop-
mental delay become evident. Neurological deterio-
ration leads to death generally before age 2. Other
forms of Krabbe disease have late infantile, juvenile,
or adult age of onset. Krabbe disease is inherited in
an autosomal recessive manner and is due to a muta-
tion in the gene for galactosylceramidase (GALC),
leading to the accumulation of galactocerebroside in
tissues. Diagnosis is made by finding 5 percent or less
of normal GALC activity. Prenatal diagnosis is feasible.
Also known as galactocerebrosidase deficiency, GALC
deficiency, and globoid cell leukodystrophy.
Krukenberg tumor
A tumor of the ovary that is
caused by the spread of metastatic cancer of the
gastrointestinal tract, characteristically from the
stomach.
KUB
Abbreviation for kidney, ureter, and bladder.
KUB film
An abdominal X-ray that shows the kid-
ney, ureter, and bladder.
kuru
A slowly progressive fatal disease of the
brain that is due to an infectious agent transmitted
among people in Papua New Guinea by ritual canni-
balism. Kuru is an infectious form of subacute
spongiform encephalopathy and is caused by a tiny
infectious particle called a prion. It appears to be
similar to bovine spongiform encephalopathy (“mad
cow disease”) and Creuztfeldt-Jakob disease. Also
called trembling disease.