Master the board step 3

Dermatology
Foliaceus is diagnosed by biopsy and treated with steroids in the same fashion
as pemphigus vulgaris.
Porphyria Cutanea Tarda (PCT)
This is a disorder of porphyrin metabolism resulting in a photosensitivity
reaction to an abnormally high accumulation of porphyrins.
The following are associated with PCT:
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Alcoholism
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Liver disease
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Chronic hepatitis C
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Oral contraceptives
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Liver disease, such as chronic hepatitis or hemochromatosis PCT, is associated
with increased liver iron stores.
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Diabetes is found in 25 percent of patients.
PCT presents with the following:
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Nonhealing blisters on the sun-exposed parts of the body, such as the
backs of the hands and the face
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Hyperpigmentation of the skin
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Hypertrichosis of the face
Diagnostic Testing
Test for urinary uroporphyrins. Uroporphyrins are elevated 2–5 times above
the coproporphyrins in this disease.
Treatment
Manage this disease as follows:
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Stop drinking alcohol.
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Stop all estrogen use.
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Use barrier sun protection.
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Use phlebotomy to remove iron. Deferoxamine is used to remove iron if
phlebotomy is not possible.
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Chloroquine increases the excretion of porphyrins.
Drug Eruptions/Hypersensitivity
Urticaria
Acute urticaria is a hypersensitivity reaction, most often mediated by IgE
and mast cell activation, which results in evanescent wheals and hives. It
is a type of localized, cutaneous anaphylaxis but without hypotension and
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