URINARY TRACT INFECTION
Kidney (cross section)
Peritoneum folded back
stone in the bladder (see
and enlargement or tumour
of the prostate (see
prostate, cancer of
). In females, causes
include pressure on the urethra from
or from a
. In either
sex, the cause may be a bladder tumour.
Retention may also be due to defective
functioning of the nerve pathways sup-
plying the bladder as a result of general
, drugs affecting
the bladder, surgery, injury to the nerve
pathways, or disease of the spinal cord.
Complete retention causes discomfort
and lower abdominal pain, except when
nerve pathways are defective. The full
bladder can be felt above the pubic bone.
However, chronic or partial retention
may not cause any serious symptoms.
Retention can lead to kidney damage
and, often, a urinary tract infection.
Treatment of retention is by catheteri-
cause is then investigated. Obstruction
can usually be treated; if nerve damage
is the cause, permanent or intermittent
catheterization is sometimes necessary.
urinary system See
urinary tract The part of the body con-
cerned with the formation and excretion
The urinary tract consists of
(with their blood and nerve
supplies), the renal pelvises (funnel-
shaped ducts that channel urine from
the kidneys), the
The kidneys make urine by filtering
blood. The urine collects in the renal
pelvises and is then passed down the
ureters into the bladder by the actions
of gravity and
. Urine is stored
in the bladder until there is a sufficient
amount present to stimulate
When the bladder contracts, the
urine is expelled through the urethra.
urinary tract infection An infection
anywhere in the
differing symptoms, depending on the
causes a burn-
ing sensation when urine is being
causes a frequent urge
to pass urine, lower abdominal pain,
and, often, general malaise
with a mild fever.
fever and pain in the back under the
ribs. Cystitis and pyelonephritis are