Porphyria

What is it?

Acute intermittent porphyria is the most common form. It's a condition where an enzyme that produces haem is missing.

The body can cope, making its own haem other ways, but it leads to build up of haem components, called porphyrins. These can be toxic to tissues if in high enough doses. It's due to a problem in the HMBS gene which is autosomal dominant.

Clinical features

In AIP, attacks cause abdominal pain, vomiting and diarrhoea or constipation. There may also be muscle weakness, seizures and mental changes.

There is often a trigger, such as drugs, alcohol or infections. The key symptom that makes it stand out is that if you leave the urine in sunlight, it will turn red, or brown. This is due to the porphyins being turned into haem by the sunlight.

What do you do?

Give them haematin and haem arginate, which get rid of the components of haem. Also chuck in some dextrose, and morphine, since the pain is baaaad.