[A family of acute intermittent porphyria].

A 62-year-old man who had twice received laparotomies for abdominal pain of unknown origin was admitted to our hospital with acute abdominal pain. His family history of acute intermittent porphyria (AIP) suggested that it arose from acute porphyria. We treated the patient with 5% glucose solution by i.v. drip infusion and his abdominal pain improved rapidly. Diagnosis of AIP was established by the demonstration of reduced erythrocyte porphobilinogen deaminase (PBGD) activity and a point mutation (CAG --> CGG) in a splicing site in intron 10/exon 11 in the PBGD gene by DNA analysis. For screening of AIP carriers in his family, we measured erythrocyte PBGD activity. Four of his seven children were successfully diagnosed as AIP carriers. This is the ninth AIP family report, in which a mutation in the PBGD gene was revealed by DNA analysis.