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Abdominal pain is one of the hallmarks of acute intermittent porphyria.
How does this occur in porphyria. Could somebody explain its mechanism?
Hey Dr. N Elham, though still i am a student, i have found some informations about this. Please read details of references.

1. How the porphyrin precursors lead to this symptom is unknown.
2. chronic pain in the gut is thought to be due to axonal nerve deterioration in affected areas of the nervous system.
3. Precipitating factors/triggers:
(1) endocrine: increase in estrogens/progesterone can induce (i.e. menstruation /OCP's)**
(2) decreased caloric intake: fasting induces hepatic heme oxygenase; therefore decreases hepatic heme concentrations and ALA-synthase repression (DM may be protective)
(3) drugs/chemicals: steroids/barbiturates; cytochrome p450 inducers (see unsafe drugs list); cocaine/amphetamines/ecstasy
(4) stress: intercurrent illness/infection/alcoholism/surgery >> upregulate heme oxygenase
(5) smoking: polycyclic aromatic hydrocarbons induce cytochrome p450 and heme synthesis
**There is evidence in some women of a relationship to hormone changes in the body, but exactly what changes precipitate the condition is not clear.
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