PINTA
PITYRIASIS ROSEA
associated with
numbness
and, some-
times, a burning feeling. The medical
term is
paraesthesia.
Transient pins-and-
needles is due to a temporary disturbance
in the conduction of nerve signals from
the skin. Persistent pins-and-needles may
be caused by
neuropathy.
pinta A skin infection, caused by
t r e -
p o n e m a c a r a t e u m ,
occurring in remote
villages in tropical America. A large spot
surrounded by smaller ones appears on
the face, neck, buttocks, hands, or feet.
After 1-12 months it is followed by red
skin patches that turn blue, then brown,
and finally white. A
penicillin drug
or
tetracycline
clears up the infection, but
the skin may be permanently disfigured,
pinworm
infestation An alternative
name for
threadworm infestation.
pioglitazone An oral
hypoglycaemic drug
that is used in combination with other
oral hypoglycaemics (either
metformin
or a sulphonyl urea) in the treatment of
type 2
diabetes mellitus.
Pioglitazone acts
by reducing peripheral insulin resistance.
Side effects may include gastrointestinal
disturbances, weight gain, and anaemia,
piperazine An
anthelmintic drug
used
to treat
infestation
by
roundworms
and
threadworms.
Possible adverse effects
include abdominal pain, nausea, vomit-
ing, and diarrhoea.
piroxicam A type of
nonsteroidal anti-
inflammatory drug
(NSAID) that is used
to relieve the symptoms of types of
arthritis,
and to relieve pain in
bursitis,
tendinitis,
and after minor surgery. Pos-
sible adverse effects include nausea,
indigestion, abdominal pain, swollen
ankles,
peptic ulcer,
and liver problems,
pituitary gland Sometimes referred to
as the master gland, the pituitary is the
most important
endocrine gland.
It regu-
lates and controls the activities of other
endocrine glands and many body pro-
cesses. The pituitary gland is a pea-sized
structure attached by a stalk of nerve
fibres to the
h}spothalamus.
The anterior
lobe produces
growth hormone; pro-
lactin; ACTH;
TSH (thyroid-stimulating
hormone), which stimulates hormone
production by the
th^nroid gland;
the
gonadotrophins
FSH (follicle stimulating
hormone) and LH (luteinizing hormone);
and melanocyte-stimulating hormone
PITUITARY GLAND
(MSH), which controls darkening of the
skin. The posterior pituitary secretes
ADH
and
ox}focin.
pituitary tumours Growths in the
pitu-
itary gland.
Pituitary tumours are rare,
and mostly noncancerous, but tumour
enlargement can put pressure on the
optic nerves,
causing visual defects.
The causes of pituitary tumours are
unknown. They may lead to inadequate
hormone production, causing problems
such as cessation of menstrual periods
or reduced sperm production. They may
also cause the gland to produce excess
hormone. Overproduction of growth hor-
mone causes
gigantism
or
acrom egaly
too much thyroid-stimulating hormone
(TSH) can lead to
h}fperth}froidism.
Investigations include blood tests,
X-rays,
MRI
of the pituitary, and usually
also
vision tests.
Treatment may be by
surgical removal of the tumour,
radio-
therapy,
hormone replacement, or a
combination of these techniques. The
drug
bromocriptine
may be used; it can
reduce production of certain hormones
and shrink some tumours.
pityriasis alba A common skin condi-
tion of childhood and adolescence.
Irregular, fine, scaly, pale patches appear
on the face. Caused by mild
eczema,
it
usually clears up with
emoUients.
pityriasis rosea A common, mild skin
disorder in which a rash of flat, scaly-
450
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