Manifestation of acute intermittent porphyria in patients with chronic inflammatory bowel disease.

In a retrospective study covering 411 acute intermittent porphyria patients, four cases of a coincidence with Crohn's disease or ulcerative colitis were found. Their courses of disease confirmed that patients with chronic inflammatory bowel disease have a higher risk for acute porphyria manifestation. Both malnutrition (glycopenic induction) and sulphasalazine (drug-induced exacerbation) are known as triggering factors for acute porphyric states. Furthermore, diagnosis of acute intermittent porphyria tends to be much more difficult in such cases, as the acute phases of abdominal pain are likely to be associated with the enteral disease process. A delay of diagnosis and therapy of acute hepatic porphyria, however, may endanger the patient by pareses, which could be irreversible or even lethal. Therefore, whenever there is suspicion of a coinciding acute porphyria, urinary screening tests for porphyria should immediately be performed and, if a coinciding acute hepatic porphyria is diagnosed, porphyrogenic drugs like sulphasalazine should be avoided in treatment of chronic inflammatory bowel disease.