JAKOB-CREUTZFELDT DISEASE
JAW, FRACTURED
Jakob-Creutzfeldt disease
See
Creutz-
feldt-Jakob disease
.
jaundice
Yellowing of the skin and the
whites of the eyes, caused by an accu-
mulation of
bilirubin
in the blood.
Jaundice is the chief sign of many disor-
ders of the
liver
and
biliary system
.
Many babies develop jaundice soon
after birth
(see jaundice, neonatal).
Bilirubin is formed from
haemoglobin
when old red cells are broken down,
mainly by the
spleen.
It is absorbed by
the liver, where it is made soluble in
water and excreted in
bile.
There are 3 main types of jaundice:
haemolytic, hepatocellular, and obstruc-
tive. In haemolytic jaundice, too much
bilirubin is produced for the liver to
process. This is caused by excessive
haemolysis
of red cells, which can have
many causes (see
anaemia
,
haem oljJic).
In hepatocellular jaundice, bilirubin
accumulates because its transfer from
liver cells into the bile is prevented,
usually due to acute hepatitis (see
hep-
atitis, acute
)
or
liver failure
.
In obstructive jaundice, also known as
cholestatic jaundice, bile cannot leave
the liver because of
bile duct obstruc-
tion
.
Obstructive jaundice
can
also
occur if the bile ducts are not present
(as in
biliary atresia
) or if they have been
destroyed by disease.
Cholestasis
then
occurs and bilirubin is forced back into
the blood. For all types of jaundice,
treatment is for the underlying cause.
jaundice, neonatal
Yellowing of the
skin and whites of the eyes in newborn
babies, due to accumulation of
bilirubin
in the blood. It usually results from the
liver
being immature and unable to
excrete bilirubin efficiently. This form of
jaundice is usually harmless and disap-
pears within a week. Rarely, severe or
persistent neonatal jaundice is caused
by
haemolytic disease of the newborn
,
G
6
PD deficiency
,
hepatitis
,
hypothyroid-
ism
,
biliary atresia
,
or infection.
Jaundiced babies usually require extra
fluids and may be treated with
photo-
therapy
. Exchange transfusion (see
blood
transfusion
)
may be needed in severe
cases. If severe neonatal jaundice is not
treated promptly,
kernicterus
may occur.
jaw
The mobile bone of the face, also
known as the mandible. The term some-
times includes the
maxilla
.
The mandible
bears the lower teeth on its upper sur-
face and is connected to the base of the
skull at the
temporomandibular joints
.
Muscles attached to the jaw allow move-
ments needed in chewing, biting, and
side-to-side and downward movement.
Mandible (lower jaw)
Maxilla
(upper
jaw)
Temporo- /
mandibular
(TM) joint
jaw , d islocated Displacement of the
lower
jaw
from one or both
temporo-
mandibular joints
.
A dislocated jaw is
usually due either to a blow or to yawn-
ing. There is pain in front of the ear on
the affected side or sides, and the jaw
projects forwards. The mouth cannot be
fully closed, making eating and speak-
ing difficult. Dislocation tends to recur.
Surgery may be carried out to stabilize
the joint but is often unsuccessful.
jaw, fractured
A fracture of the jaw,
most often caused by a direct blow. A
minor fracture may cause tenderness,
pain on biting, and stiffness. In more
severe injuries, teeth may be loosened
or damaged, jaw movement may be sev-
erely limited, and there may be loss of
feeling in the lower lip. Minor fractures
are normally left to heal on their own.
For severe fractures with displacement
of the bones, surgical treatment is nec-
essary. To allow healing, the jaw is
immobilized, usually by wiring the upper
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