I
DIABETES MELLITUS
LIVING WITH DIABETES MELLITUS
As the level of glucose in the blood
rises, the volume of urine required to
carry it out of the body is increased,
causing not only a frequent need to
urinate but also constant thirst. The
high levels of sugar in the blood and
urine impair the body’s ability to
fight infection, leading to urinary
tract infections (such as
c y s t i t i s
and
p y e l o n e p h r i t i s ) ,
vaginal yeast
infections
( c a n d i d i a s i s ) ,
and
recurrent skin infections.
Because the body’s cells are
starved of glucose, the sufferer
feels weak and fatigued (see right).
The cells are able to obtain some
energy from the breakdown of
stored fat, resulting in weight loss.
The chemical processes involved in
this breakdown of fat are, however,
defective, especially in insulin-
dependent diabetics. They lead
to the production of acids and
substances known as ketones,
which can cause coma and
sometimes death.
Other possible symptoms of
undiagnosed diabetes include
blurred vision, boils, increased
appetite, and tingling and numbness
in the hands and the feet.
Symptoms will develop in every
untreated person who has insulin-
dependent (Type
1
) diabetes, but
will appear in only one third of
those who have the noninsulin-
dependent form (Type
2
). There are
many people with Type
2
diabetes
who are unaware of it. The disease
is often diagnosed only after
complications of the diabetes have
been detected.
diabetes mellitus
SELF-MONITORING OF
BLOOD GLUCOSE LEVELS
Testing of
blood glucose
A spring-loaded
pricking device is
used to obtain
blood from the
fingertip. A drop of
blood is spread on
to a chemically
impregnated strip.
The strip is inserted
into a digital
glucose meter,
which analyses the
blood and gives an
almost instant
reading of the
glucose level.
DEVICES FOR INJECTING INSULIN
Insulin can be injected using a disposable syringe
and needle or a pen with refill cartridges (below),
or it may be infused continuously from a portable
pump (right).
I n s u lin
p e n
R e fill c a r t r i d g e
I
Insulin pen
This device is useful if multiple
dailyinjections are needed.
Portable pump
The pump infuses insulin
byway ofa cannula
inserted through the skin
D
to pass a large volume of urine. The
person’s response to synthetic ADH may
also be tested; if the urine output
remains high even after the person has
taken ADH, this indicates the nephro-
genic form of the disease.
Treatment of ADH-related diabetes
insipidus is with desmopressin (syn-
thetic ADH). Treatment of nephrogenic
diabetes insipidus is by a low-sodium
diet and thiazide
diuretic drugs.
diabetes mellitus
A disorder that develops when the cells
of the body do not receive enough
insulin.
This hormone is produced by
the
pancreas;
it normally enables body
cells to take in glucose from the blood
to generate energy, and enables the
liver
and fat cells to take in glucose for stor-
age. A lack of insulin in the cells may
occur because the
pancreas
produces
too little, or none at all; alternatively, it
may occur because the tissues are resis-
tant to the hormone’s effects.
TYPES, CAUSES, AND INCIDENCE
There are two main types of diabetes
mellitus, both of which tend to run
in families. Type 1 (insulin-dependent)
diabetes usually develops suddenly in
childhood or adolescence. This type of
diabetes is an
autoimmune disorder
in
which the immune system
destroys
insulin-secreting cells in the pancreas
and insulin production ceases. Affected
people may be genetically predisposed
to developing the condition; the disease
process may be triggered by viral infec-
tion. They must have insulin injections
or they may fall into a coma and die.
Type 2 (non-insulin-dependent) dia-
betes tends to develop gradually, mainly
in people over the age of 40. This type
is becoming more common in younger
people, however, and is probably linked
to dieting. Although insulin is still pro-
duced, there is not enough to meet
the body’s needs because the tissues
become relatively resistant to its effects.
Obesity and inheritance are possible
contributory factors; many people who
develop Type 2 diabetes are overweight,
and affected people often have close rel-
atives with the condition.
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