A high fever of up to 40°C suddenly dev-
elops, with shivering, headache, muscle
pains, nausea, and vomiting. The symp-
toms persist for 3–6 days, culminating in
a crisis with a risk of collapse and death.
The person then apparently recovers but
suffers another attack 7–10 days later. If
tick-borne, there may be several such
relapses, each progressively milder.
The spirochaetes can be seen in a
blood smear, and they can be elimina-
ted with antibiotic drugs.
relationship counselling Formerly
known as marriage guidance, relation-
ship counselling is a type of professional
therapy for established partners aimed
at resolving the problems within their
relationship. The couple attends regular
sessions together in which the counsellor
promotes communication and attempts
to help resolve differences between the
partners. Relationship counselling is
largely based on the ideas and methods
of behaviour therapy. If some of the
couple’s problems are sexual, the coun-
sellor may refer them for sex therapy.
relaxation techniquesMethods of con-
sciously releasing muscular tension to
achieve mental calm. They can assist
people with anxietysymptoms, help to
reduce hypertension, and relieve stress,
and may help pregnant women to cope
with labour pains (see childbirth, natural).
Active relaxation consists of tensing
and relaxing each of the muscles in turn.
Passive relaxation involves clearing the
mind and concentrating on a phrase or
sound. Breathing exerciseshelp to pre-
vent hyperventilation, which often brings
on or worsens anxiety. Traditional con-
centration methods, such as yoga and
meditation, employ similar techniques.
releasing factorsA group of hormones,
produced by the hypothalamusin the
brain, that stimulates the release of other
hormones. Luteinizing hormone-releasing
hormoneis one such releasing factor.
remAn outdated unit of absorbed radi-
ationdose, now superseded by the
sievert. (See also radiation units.)
remissionA temporary disappearance
or reduction in the severity of the symp-
toms of a disease, or the period during
which this occurs.
renalRelated to thekidney.
renal biopsySee kidney biopsy.
renal cell carcinomaThe most com-
mon type of kidney cancer.
renal colicSpasms of severe pain on one
side of the back, usually caused by a
kidney stone (see calculus, urinary tract)
passing down the ureter. There may also
be nausea, vomiting, sweating, and blood
in the urine. Treatment is usually with
bed rest, plenty of fluids, and injections
of an analgesic drug, such as pethidine.
renal failureSee kidney failure.
renal transplantAnother term for kid-
ney transplant.
renal tubular acidosisA condition in
which the kidneysare unable to excrete
normal amounts of acid made by the
body. The blood is more acidic than nor-
mal,and the urine less acidic. Causes
include kidney damage due to disease,
drugs, or a genetic disorder; but in many
cases the cause is unknown. The acidosis
may result in osteomalacia, kidney stones
(see calculus, urinary tract), nephrocalci-
nosis, and hypokalaemia (an abnormally
low level of potassium in the blood).
reninAn enzymeinvolved in the regula-
tion of blood pressure.When the blood
pressure falls, the kidneysrelease renin,
which changes a substance called angio-
tensinogen into angiotensin I. This is
rapidly converted into angiotensin II,
which acts to increase blood pressure.
renographyA technique that uses a
radioactive substance to measure kid-
neyfunction. Renography is quick and
painless and is used when obstruction
of the passage of urineis suspected.
The radioactive substance is injected
into the bloodstream and passes through
the kidneys into the urine. Radiation
counts are taken continually throughout
the procedure. Normally, the count rises
and then falls as the substance passes
into the bladder. If obstruction is pre-
sent, the substance accumulates in the
kidneys and the count continues to rise.
(See also kidney imaging.)
repaglinideAn oral hypoglycaemicdrug
used either alone or in combination with
metforminin the treatment of type 2
diabetes mellitus. Repaglinide stimu-
lates the release of insulin. Side effects
may include abdominal pain, diarrhoea
or constipation, nausea, and vomiting.RELATIONSHIP COUNSELLING REPAGLINIDE
R