Hepatic and bile porphyrins in patients with protoporphyria and liver failure

The livers of patients who have protoporphyria and hepatic failure contain large amounts of pigment crystals. Two such patients underwent liver transplantation, providing the opportunity to identify the pigment crystals. Portions of liver were digested enzymically, sedimented through a sucrose gradient, treated with 1% sodium dodecylsulfate, and centrifuged to purify the crystals. Spectrophotometric and high-performance liquid chromatography analysis demonstrated them to be composed of protoporphyrin. Bile samples were obtained from the 2 patients, 4 other patients who did not have liver disease, and 10 control subjects. The porphyrin concentrations in bile from the 6 patients were significantly increased above controls (range 254-7884 micrograms/dl compared with 11-109 micrograms/dl). The ratio of protoporphyrin to bile acid in bile distinguished the 2 patients with advanced liver disease (3105 and 2756 micrograms/mmol) from the 4 patients without liver disease (range 61-926 micrograms/mmol). Thus, analysis of bile from patients with protoporphyria may help in evaluating their hepatobiliary status.