Porphyria is a fascinating disease. It is an Unknown Disease, but a very old disease going back to the beginning. Tests were not available for identifying the specific types, or mutations, and it was thought to be variants of all the same disease.
Some researchers refer to it as port wine.
The reason for this was due to the fact that the prominent metabolites are pyrroles. However the name never came to be used. As long as there has been human life, there has been porphyria. Porphyria began at the beginning of time and has continued to mutate throughout ensuing generations. At one time the abdominal pain was actually thought to be from the liver.