CYSTINOSIS
all of the bladder is removed) is fol-
lowed
by
the
construction
of
an
alternative
channel for
urine
, usually
ending in a
stoma
in the lower abdomen
(see
urinary diversion
) .
In
men,
the
prostate gland
and
seminal vesicles
are
also removed, usually resulting in
impo-
tence
.
In women, the
uterus
,
ovaries
,
and
fallopian tubes
are removed. After radical
cystectomy, the patient has to wear an
external pouch to collect urine.
cysticercosis
An infection, w hich is rare in devel-
oped countries, caused by the larvae of
the pork
tapeworm
.
The disease is char-
acterized by the presence of
cysts
in the
muscles and brain, w hich are formed
by the worms during their larval stage.
A serious and potentially fatal
genetic
disorder
,
characterized by a tendency to
develop chronic lung infections com-
bined with an inability to absorb fats
and other nutrients from food. The
main
characteristic feature
of cystic
fibrosis (CF) is the secretion of sticky,
viscous mucus in the nose, throat, air-
ways, and intestines.
CAUSES
CF is caused by an inherited defect in a
gene
.
The
defect is recessive, w hich
means that one faulty gene must be
inherited from each parent before any
abnormality appears. People with only
one defective gene have no symptoms
but are “ carriers” and can pass the gene
on to their children.
A rare
genetic disorder
in w hich the
amino acid
cystine accumulates in cells
throughout the body
cystic fibrosis
HOW CYSTECTOMY IS DONE
Radical cystectomy is a major
procedure performed under general
anaesthesia. An incision is made in
abdomen, and the ureters are cut
and tied. The bladder and other lower
abdominal organs are removed. The
stoma is then formed from part of the
small intestine. After the operation,
the patient is given intravenous
infusions of fluids, salt, and glucose
until the intestines are functioning
normally again.
Men
In men,
the prostate
gland and
the bladder
are removed
B l a d d e r
P r o s t a t e g l a n d
L a r g e in t e s t i n e
U r e t e r s
u s u a lly
c u t h e r e
L in e o f
i n c is io n
Women
In women,
the uterus,
fallopian tubes,
ovaries, and
part of the
vagina (as well
as the bladder)
are removed
B l a d d e r
U t e r u s
L a r g e i n t e s t i n e
K i d n e y
U r e t e r
P i e c e o f s m a l l
i n t e s t i n e w it h
b l o o d s u p p l y
in t a c t
Formation of the stoma
A short section of small intestine, with its blood
vessels, is detached from the remainder of the
intestines. The two ureters are joined to this
loop of intestine. One end of the loop is then
sealed, and the other inserted through the
abdominal wall to form the stoma.
Urine expulsion
Urine produced by the kidneys is channelled via
the ureters and intestinal loop to the stoma,
where it leaves the body.
The defective gene causes a biochemical
abnormality in w hich the faulty move-
ment of ions across cell membranes
affects mucus formation. As a result, the
mucus-forming glands in several organs
do not function properly. Most serious-
ly,
the
glands in the
lining
of the
bronchial tubes produce thick mucus,
w hich predisposes the person to chron-
ic
lung
infections.
Another
serious
malfunction is poor or absent secretion
of
pancreatic
enzymes,
w hich
are
involved in the breakdown and absorp-
tion of fats in the intestine. The sweat
glands are also affected and excrete
excessive amounts of salt.
SYMPTOMS AND COMPLICATIONS
The course and severity of CF vary. Typi-
cally, a child passes unformed, pale, oily,
foul-smelling
faeces
and
may
fail
to
thrive. Often, growth is stunted and the
child has recurrent respiratory infections.
Without prompt treatment,
pneumonia
,
bronchitis,
and
bronchiectasis
may devel-
op, causing lung damage. Most males
and some females are infertile. Excessive
salt loss from sweating may lead to
heat-
stroke
and collapse.
DIAGNOSIS AND TREATMENT
Early diagnosis, confirmed by simple
sweat and blood tests, improves the out-
look
for
children
with
CF.
Prompt
treatment with intensive
physiotherapy
and
antibiotics
helps to reduce the seve-
rity and frequency of lung infections.
In addition, lung function may be im -
proved by treatment with dornase alfa, a
genetically
engineered
version
of a
human enzyme, w hich is administered
by
nebulizer. Pancreatin
and a diet rich in
proteins and calories are given to bring
about weight gain and encourage more
normal faeces. Supervision of the treat-
ment is best carried out from a special
centre that is staffed by paediatricians,
nurses, and physiotherapists who have
particular knowledge of the disease.
OUTLOOK
The highly specialized treatment now
available for people with CF maximizes
their chances of a reasonable quality of
life. About 9 in 10 children survive into
their teens; many live well into their
40s. Progressive respiratory failure is
the usual cause of death, but in some
cases a heart-lung transplant may be
considered.
cystinosis
C
209
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