EVIDENCE FOR NEUROLOGICAL DYSFUNCTION IN END-STAGE PROTOPORPHYRIC LIVER-DISEASE

Protoporphyria is a genetic disorder characterized by a defect in the enzyme ferrochelatase, which catalyzes the chelation of iron to protop orphyrin. This causes excessive accumulation and excretion of protopor phyrin. The predominant clinical feature is photosensitivity. Progress ive and fatal liver disease occurs in a small percentage of cases. We report our experience with eight patients with end-stage protoporphyri c liver disease in whom a syndrome developed before transplantation th at resembled the neurological crises of the acute porphyrias. This syn drome was characterized by abdominal pain, hypertension, tachycardia, extremity pain and weakness, constipation and nausea and vomiting. Ery throcyte and serum protoporphyrin levels were markedly increased in al l patients. In one patient, profound hemolysis developed during the an hepatic phase of transplantation and continued over a period of 72 hr, causing an extreme increase in the serum protoporphyrin level. Progre ssive weakness deteriorated to paralysis in this patient. This phenome non suggests that protoporphyrin may gain access to neural tissue when serum levels are markedly increased, causing neurotoxicity.