When the kidneys start to fail, toxins are not filtered out of
the blood, and start accumulate in the tissues. This is
dangerous because water, waste, and toxic substances build up
that normally are removed from the body by the kidneys.
Build up of
two waste products, urea and creatinine, can lead to tiredness,
weakness, loss of appetite and vomiting.
Kidney
failure is also associated with an increase in the volume of
water in the body which can result in a swelling of the tissues.
Excess salt
and water retention may cause high blood pressure, swelling of
the legs, face, abdomen and breathlessness.
The most
serious complication of salt and water overload in acute kidney
failure (usually iatrogenic) is the development of pulmonary
oedema.
Hyperkalaemia
is most commonly dangerous in the context of acute renal
failure, and is important because it can cause cardiac arrest.
Accumulation
of acid generated during the body's metabolic processes can lead
to a condition called metabolic acidosis.
Failure to
get rid of phosphate, causes the blood phosphate level to
increase and calcium level to fall.
When calcium
level is low, bones will become brittle.
The kidney
may also lose its ability to produce erythropoietin, resulting
in anaemia.
It
also causes other problems such as
anemia,
high blood pressure, and bone
disease in the body by impairing hormone production by the
kidneys.
