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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.
[Ref. http://emedicine.medscape.com/article/205220-overview]
2. chronic pain in the gut is thought to be due to axonal nerve deterioration in affected areas of the nervous system.
[Ref. http://en.wikipedia.org/wiki/Porphyria,_acute_intermittent]
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
[Ref. http://www.med.unc.edu/medicine/web/porphyria.pdf]
**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.
[Ref.http://www.cpf-inc.ca/AIP.htm]
 
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