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GASTROINTESTINAL COMPLICATION
Clinical complications of chronic
kidney
failure
The
clinical complications of chronic
kidney failure are
widespread
such as:
Gastrointestinal System
Anorexia
and nausea are almost universal symptoms in uraemia
and are accompanied by a blunting of taste. Both
lead to decreased caloric intake and malnutrition.
If there is poor oral hygiene, mouth bacteria will
break down urea in saliva to ammonia, giving an
unpleasant taste in the mouth and uriniferous smell
to the breath. Patients often suffer early morning
vomiting in the late stages of renal failure. These
upper gastrointestinal symptoms are aggravated or
even caused by opioid analgesics, the metabolites of
which accumulate in renal failure. Diverticular
disease is a problem in dialysis patients who may
become constipated because of a reduction in the
fluid and bulk of their diet. Patients on dialysis
with primary amyloid are, for the same reasons, more
at risk of perforation of the colon.
Gastrin
levels are higher in patients with chronic renal
failure than in controls, but peptic ulceration is
not obviously more common than in the general
population. However, gastrointestinal haemorrhage,
both acute and chronic, is believed to be more
common in renal failure and is attributed to
angiodysplasia or non-specific gastric ulceration
aggravated by the platelet dysfunction of uraemia.
The chronic blood loss is more noticeable because
the erythroid bone marrow is already near the limit
of compensation for shortened red cell survival.
Clostridium difficile is endemic in renal units.
Elderly patients in particular often develop
pseudomembranous colitis after treatment with
broad-spectrum antibiotics, especially
cephalosporins. Treatment is with oral metronidazole
or vancomycin, but if a toxic megacolon develops
then colectomy is essential to preserve life.
Pancreatitis is only more common in uraemia because
it can be provoked by hypercalcaemia, which is a
hazard of vitamin D-analogue treatment. Chronic
dialysis patients do have a fibrotic pancreas, but
this does not seem to have clinically relevant
effects on exocrine secretion.
Hepatitis B infection, if contracted in the presence
of renal failure, is likely to become chronic.
Patients fail to clear the virus because of their
depressed cell-mediated immunity, but they seldom
develop severe hepatitis or chronic liver disease.
Hepatitis C infections are only more common in renal
failure because of exposure to blood transfusions
and its transmission in haemodialysis units. The
natural history does not seem different in patients
in renal failure.
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