REFLUX
RELAPSING FEVER
R
reflux An abnormal backflow of fluid in
a body passage due to failure of the
passage's exit to close fully. A common
type of reflux is
regurgtation
of acid
fluid from the stomach (see
acid reflux).
refraction The bending of light rays as
they pass from one substance to anoth-
er. It is the mechanism by which images
are focused on the
retina
in the eye.
regression A term used in
psychoana-
lytic theory
to describe the process of
returning to a childhood level of behavi-
our, such as thumb-sucking.
regurgitation A backflow of fluid. In
medicine, the term is used to describe
the return of swallowed food or drink
from the stomach into the
oesophagus
and mouth. The term is also used to
describe the backflow of blood through
a
heart valve
that does not close fully
because of a disorder such as
mitral
incompetence.
(See also
reflux.)
rehabilitation Treatment aimed at enab-
ling a person to live an independent life
following injury, illness,
alcohol depen-
dence
, or
drug dependence
. Treatment
may include
physiotherapy
,
occupational
therapy
, and
psychotherapy
.
In a rehabilitation centre, a person's
disability
or dependence is assessed
and a treatment programme is devel-
oped. Industrial rehabilitation centres
provide job retraining for those who
cannot return to their previous employ-
ment. Drug and alcohol rehabilitation
centres help people through withdrawal
and provide psychological support.
rehydration, oral See
rehydration ther-
apy.
rehydration therapy The treatment of
dehydration
by administering fluids and
salts by mouth (oral rehydration) or by
intravenous infusion
. The amount of fluid
necessary depends on age, weight, and
the degree of dehydration. Mild dehy-
dration can usually be treated with oral
solutions, which are available as effer-
vescent tablet or powder to be made up
at home. In severe dehydration, or if the
patient cannot take fluids by mouth
because of nausea or vomiting, an
intra-
venous infusion
of
saline
and/or
glucose
solution may be given in hospital.
reimplantation, dental Replacement of
a
tooth
in its socket after an accident so
that it can become reattached to sup-
porting tissues. The front teeth are most
commonly involved. The tooth needs to
be reimplanted soon after the accident
and is maintained with a splint (see
splinting
,
dental
) while it heals. Healing
may take several weeks.
Reiter's syndrome A condition in which
there is a combination of
urethritis
,
re-
active arthritis
, and
conjunctivitis
. There
may also be
uveitis.
Reiter's syndrome is
more common in men.
The syndrome is caused by an
immune
response
and usually develops only in
people with a genetic predisposition.
Most patients have the HLA-B27 tissue
type (see
histocompatability antigens
).
The syndrome's development is induced
by infection: usually
nongonococcal ure-
thritis
, but sometimes bacillary
dysentery
.
Reiter's syndrome usually starts with a
urethral discharge, which is followed by
conjunctivitis and then arthritis. The
arthritis usually affects
1
or
2
joints
(usually the knee and/or ankle) and is
often associated with
fever
and
malaise.
Attacks can last for several months.
Tendons
,
ligaments
, and tissue in the
soles of the feet may also become in-
flamed. Skin rashes are common.
Diagnosis is made from the symptoms.
Analgesic drugs
and
nonsteroidal anti-
inflammatory drugs
relieve symptoms
but may have to be taken for a long peri-
od.
Relapses
occur in about 1 in 3 cases.
rejection An
immune response
aimed at
destroying organisms or substances that
the body's
immune system
recognizes as
foreign. Rejection commonly refers to
the nonacceptance of tissue grafts or
organ transplants. To avoid rejection,
donor tissues are closely matched to
the recipient (see
tissue-typing
).
Immuno-
suppressant drugs
,
corticosteroid drugs
,
and
ciclosporin
are given to organ trans-
plant recipients to suppress rejection.
(See also
grafting; transplant surgery.)
relapse The recurrence of a disease
after an apparent recovery, or the return
of symptoms after a
remission
.
relapsing fever An illness caused by
infection with
spirochaetes.
Relapsing
fever is transmitted to humans by
ticks
or
lice
and is characterized by high fever.
It does not occur in the UK.
484
previous page 482 BMA Illustrated Medical Dictionary read online next page 484 BMA Illustrated Medical Dictionary read online Home Toggle text on/off