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SKIN COMPLICATION
Clinical complications of chronic
kidney
failure
The
clinical complications of chronic
kidney failure are
widespread
such as:
Skin
The
effects of uraemia on the skin are obvious and cause
much distress to the patients. Yellow-brown
pigmentation prominent in sun-exposed areas is a
feature of prolonged chronic renal failure. It is
attributed to an effect of retained
melanocyte-stimulating hormone (MSH), retention of
vegetable-derived lipochrome and carotenoids, and
iron.
Pruritus
is the most exasperating symptom for both patient
and nephrologist because it is so difficult to
treat. It is associated with xerosis (dry skin) and
is worse when the skin is warm. A number of
explanations are advanced including sensitivity to
histamines, a raised calcium phosphate product, and
uraemia itself. The itch–scratch cycle can lead to
infection and nodular prurigo. Treatment includes
starting or increasing dialysis, applying skin
emollients, controlling the plasma phosphate level,
keeping cool, and the prescription of
antihistamines, for example chlorphenamine
(chlorpheniramine) 4 mg at night (which is also
slightly sedative). Naltrexone, an opioid
antagonist, and ultraviolet phototherapy are
effective in the short-term.
Cutaneous and subcutaneous calcification
(calciphylaxis), a result of small-vessel
calcification and occlusion, leads to painful livedo
reticulosis and ischaemic ulceration. Once
established, it is difficult to treat.
Bullous
eruptions in sun-exposed areas, mimicking those of
porphyria, are seen in dialysis patients. They are
attributed to retained uroporphyrins or other
photosensitizing chemicals that inhibit porphyrin
breakdown. Iron excess is implicated in the
pathogenesis, so phlebotomy and erythropoietin are
part of the treatment.
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