[Diagnosis of acute intermittent porphyria. Results of neurological, biochemical and genetic studies].

Neurological and biochemical studies have been performed on four AIP families with 21 members. Five patients suffered from manifested AIP (Uroporphyrinogen Synthase defect and characteristic urine findings); among their relatives five persons with latent AIP were detected and eight carriers of the genetic-enzymic defect (Uroporphyrinogen Synthase defect). Internal and neurological symptoms could be interpreted as a panneuropathy. Acute and chronical polyneuropathies could be observed as well as myelopathies and cerebral co-reactions. A frequent symptom dominating the crisis and the latent state of AIP were etiologically abscure 'myalgias.' The character of the course of AIP is various and dubious: beyond the 'classical' courses with its intermittent porphyric crises we observed one case which was characterized by a permanent crisis and a second case marked by a chronical, slow progredient course without any porphyric attacks.