[Acute hepatic porphyria and its neurological syndrome]

Certain of the hepatic porphyrias are classified as belonging to the acute hepatic prophyrias, namely acute intermittent porphyria (AIP), variegate porphyria (VP), hereditary coproporphyria (HCP) and ALA-dehydrase deficiency. The common feature of all acute hepatic porphyrias is the sudden onset of neurological symptoms. The whole syndrome consists of acute abdominal pain crises with autonomic dysfunction, global or focal central nervous system involvement and a predominantly motor polyneuropathy. Mono- or oligosymptomatic manifestations of acute porphyrias occur and are probably underestimated. The laboratory diagnosis of porphyria depends on the measurement of porphyrin precursors in urine, whereas the measurement of porphyrins in urine and feces is essential for evaluation of the porphyria type. Enzyme measurements are used to identify asymptomatic family members whose quantitative excretions of porphyrins are normal. At present the pathogenesis of neurological manifestations of acute porphyrias remains an unsettled question. The major hypotheses are discussed in this paper. The most important precipitating factor in acute hepatic porphyrias is drug ingestion. As many new drugs have not been in use for sufficiently long periods to assess their porphyrogenic activity, it is safer to avoid drugs in patients with porphyria. The most effective treatment of porphyria attacks is the administration of heme. Among the porphyria patients with epileptic seizures requiring antiepileptic medication, treatment with bromides should be taken into consideration.