Porphyria Support Group
The porphyrias are inherited or acquired disorders of certain enzymes in the heme biosynthetic pathway (also called porphyrin pathway). The hepatic porphyrias primarily affect the nervous system, resulting in abdominal pain, vomiting, acute neuropathy, seizures, and mental disturbances, including hallucinations, depression, anxiety, and paranoia.
I have suffered for many years with an auto-immune disease called Myasthenia Gravis. I have failed treatment largely but also have several additional symptoms which seem to suggest there might be something other than MG going on at the same time. I suffer bouts of severe abdominal pain and diarrhoea and nausea without any definite cause. I also get severe muscle pain in my limbs and back and have even suffered at times from hallucinations at the times of illness. Years back I was tested for porphyria and had a positive stool result but negative plasma and urine. The test was done at a time in between illnesses. I never had the DNA tests because the doctor decided to put everything down to my Myasthenia instead. The fact that I am not responding adequately to the Myasthenia treatment and my abdominal symptoms make me worry that the doctors are missing something. Could this be porphyria. Do you get false positive stool studies? Do stool, urine and plasma porphyrins have to be raised for a diagnosis? Just to mention that whilst I am sensitive to the sun I don't have any severe skin symptoms. Any advice would be appreciated!
Detecting porphyria can be very difficult and can often be negative in-between flare up periods. Sadly, unless you are having an acute attack and manage to get into a doc that will run the porphyrin test on you for the attack then you may go with out dx for a while. ER's rarely run the tests because it is so rare. I'd start doing your research (tons of internet medical information on the various forms). Mine is mostly cutaneous so I can't go out in any sunlight without extreme skin burning and then liver pain, but yours sounds like the more common forms so I'd say do some research and try to get back into a doc that knows about porphyria.