Porphyria and anorexia: cause and effect.

Porphyrias are hereditary disorders related to impaired biosynthesis of heme and characterized by multisystemic manifestations. Acute intermittent porphyria (AIP) is the most common acute subtype of the disease, and often associated with psychiatric symptoms. We here report a patient who developed acute flaccid paralysis after remarkable weight loss, which was related to an eating disorder (anorexia nervosa). After an extensive neurologic workup, he was diagnosed with AIP. This case emphasizes a deleterious vicious cycle between AIP and anorexia: porphyria may lead to anorexia and the carbohydrate restriction may lead to recurrent porphyric attacks. Therefore, an interruption of this cycle with psychiatric approaches to the eating disorders is crucial for long-term therapeutic efficacy.