Below is an instruction from Human. Write a response.
    ### Instruction:
    What to do for Porphyria ?
    ### Response:
    - Porphyrias are rare disorders that affect mainly the skin or nervous system and may cause abdominal pain.  - Each of the eight types of porphyria corresponds to low levels of a specific enzyme in the heme biosynthetic pathway.  - The exact rates of porphyria are unknown and vary around the world.
    