Not all blistering on the legs is due to conventional disease.
Sometimes physical factors alone are responsible. We are seeing this phenomenon
more commonly in the elderly patient with severely sun damaged skin. Sometimes
the skin on the lower leg is thin like paper. The underlying dermis has lost
all its supporting collagen and elastic tissue. When the patient develops mild
cardiac or renal failure and starts to have fluid retention that fluid
accumulates in the lower legs and feet Fluid leaks from the capillaries and
accumulates in the dermis. This leads to separation of the epidermis from the
dermis at the dermo epidermal junction. If a biopsy is taken it will be
reported as a sub epidermal blister but without inflammatory changes.
Immunofluorescence and porphyrin studies will be negative. Slight injury to the
skin will cause clear fluid to pour from the skin on to the floor. Treatment is
with support stockings and treatment of the underlying cause of the oedema. See
www.skinconsult.com.au for other
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