prostatitis, cystitis, bladder cancer (see
bladder tumours), and bladder stones
(see calculus, urinary tract).
strappingThe application of adhesive
tape to part of the body to exert pres-
sure and hold a structure in place.
strawberry naevusA bright red, raised
spot which appears in early infancy. It is
a type of haemangioma.
strep throatA streptococcal infectionof
the throat. It is most common in chil-
dren. The bacteria are spread in droplets
coughed or breathed into the air.
In some people, the bacteria cause no
symptoms, but others suffer a sore throat,
fever, and enlarged lymph nodes in the
neck. In some cases, the bacterial toxins
produce a rash (see scarlet fever).
Treatment is usually with a penicillin
drug. Untreated, strep throat may lead
to glomerulonephritisor rheumatic fever.
streptococcal infections Infections
caused by bacteriaof the STREPTOCOCCUS
group. A particular type, haemolytic strep-
tococci, can cause tonsillitis, strep throat,
scarlet fever, otitis media, pneumonia, ery-
sipelas, and wound infections. Another
type is often responsible for urinary tract
infection, and another can cause bacterial
endocarditisif it enters the bloodstream.
streptokinaseA thrombolytic drug used
to dissolve blood clots following a myo-
cardial infarctionor pulmonary embolism.
Side effects include nausea, rash, and
cardiac arrhythmias.
streptomycinAn antibiotic drugused to
treat a number of uncommon infections,
including tularaemia, plague, brucellosis,
and glanders. It may damage nerves in
the inner ear, disturbing balance and
causing dizziness, tinnitus, or deafness.
Other side effects are facial numbness,
tingling in the hands, and headache.
stressAny interference that disturbs a
person’s mental and physical well-being.
Stress may be experienced in response
to a range of physical and emotional
stimuli. When faced with stressful situ-
ations, the body responds by increasing
production of the hormones adrenaline
(epinephrine) and cortisol, which pro-
duce changes in heart-rate, blood
pressure, and metabolismto improve
performance. However, at a certain level,
they disrupt a person’s ability to cope.Continued exposure to stress often
leads to mental and physical symptoms,
such as anxietyand depression, indiges-
tion, palpitations, and muscular aches
and pains. Post-traumatic stress disorder
is a direct response to a specific stressful
event. (See also relaxation techniques.)
stress fractureA fracturethat occurs as
a result of repetitive jarring of a bone.
Common sites include the metatarsal
bones in the foot (see March fracture),
the tibia or fibula, the neck of the femur,
and the lumbar spine. The main symp-
toms are pain and tenderness at the
fracture site. Diagnosis is by bone imag-
ing. Treatment consists of resting the
affected area for 4–6 weeks. The fracture
may be immobilized in a cast.
stress ulcerAn acute peptic ulcerthat
develops after shock, severe burns or
injuries, or during a major illness. Stress
ulcers are usually multiple and are most
common in the stomach. The exact
cause is unknown. Drugs are often given
to severely ill patients in hospital to pre-
vent the development of stress ulcers.
stretcherA frame covered with fabric
that is used in first aid for carrying the
sick, injured, or deceased.
stretch-markAnother name for stria.
striaAlso called a stretch-mark, a line on
the skincaused by thinning and loss of
elasticity in the dermis. Striae first appear
as red, raised lines. Later they become
purple, eventually fading to shiny streaks.
Striae often develop on the hips and
thighs during the adolescent growth
spurt, especially in athletic girls. They are
a common feature of pregnancy, occur-
ring on the breasts, thighs, and lower
abdomen. Purple striae are a character-
istic feature ofCushing’ssyndrome.
Striae are thought to be caused by an
excess of corticosteroid hormones. There
is no means of prevention, but in some
cases laser treatment may be used.
strictureNarrowing of a duct, canal, or
other passage in the body.
stridorAn abnormal breathing sound
caused by narrowing or obstruction of
the larynxor trachea. Stridor is most
common in young children. It usually
occurs in croup. Other causes include
epiglottitis, an inhaled foreign body, hy-
pocalcaemia, and some larynx disorders.STRAPPING STRIDORS