KURSK STATE MEDICAL
DEPARTMENT OF SKIN AND VENEREAL
HEAD OF THE DEPT.-Prof. Silina L.V.
Porphyria Cutanea Tarda
Presented by :
4th year ,group 5
The porphyrias are caused by deficiencies
of enzymes involved in heme biosynthesis
which lead to blockade of the porphyrin
pathway and subsequent accumulation of
porphyrins and their precursors.
Seven major types of porhyria are now
They include acute and non-acute
Cutaneous features are not seen in acute
intermittent porphyria (AIP) or the
rare aminolevulinic acid dehydratase
(ALA-D) deficient porphyria.
Erythropoietic protoporphyria and
congenital erythropoietic porphyria are
characterized by porphyrins produced
mainly in the bone marrow. The
reminder are primarily hepatic porhyrias.
Excessive concentrations of porhyrins
exposed to day-light generate free
radicals, leading to cell membrane
damage and cell death.
The type of cellular damage depends on
the solubility and tissue distribution of the
porphyrins. Two main patterns of skin
damage are seen in the porphyries:
accumulation of water soluble uro- and
coproporphyrins leads to blistering.
accumulation of the lipophilic
protoporphyrins leads to burning
It is the most common porphyria.
It may be acquired (type I)
genetically inherited (typeII).
60% of PCT patients are male, most of whom
ingest excess alcohol.
Women who develop PCT are often on
Most patients are ≥ 40years, and 66% have
evidence of iron overload.
Iron overload leads to reduce activity of the
uroporphyrinogen decarboxylase enzyme which
leads to elevated porphyrin levels, in particular
Associated disorders :
PCT presenting in a young adult should lead to
consideration of HIV infection , alternatively
familial PCT could be the explanation.
familial PCT (typeII) accounts for 10-20 % of
cases. It is inherited as an autosomal dominant
Most PCT is acquired (typeI) and multifactorial in
Other porphyrias, pseudoporphyrias, and photoaggravated bullous
dermatoses can manifest with clinical features indistinguishable
from those of porphyria cutanea tarda. Failure to obtain sufficient
biochemical confirmation of the diagnosis can lead to inappropriate
treatment of non–porphyria cutanea tarda disorders.
Epidermolysis Bullosa Acquisita
Lupus Erythematosus, Bullous