differential diagnosis

Last reviewed 01/2018

These include:

  • variegate porphyria
  • hepatoerythropoietic porphyria
  • scleroderma
  • pellagra
  • polymorphous light eruptions
  • bullous erosive conditions:
    • pemphigus
    • pemphigoid
    • dermatitis herpetiformis
    • epidermolysis bullosa

Careful examination of porphyrins in urine (markedly increased uroporphyrin), stool (slighty increased coproporphyrin) and plasma (increased protoporphyrin) will almost always permit confirmation of PCT.