Erythropoietic protoporphyria (EPP) is a rare inherited disorder of the heme biosynthetic pathway in which toxic levels of protoporphyrins often precipitate in the liver, leading to cirrhosis, liver failure, and the need for liver transplantation (OLT). Because the underlying enzyme defect in EPP is bone marrow derived, the risk for recurrent EPP allograft dysfunction is high. Although plasmapheresis may ameliorate acute allograft disease, strategies to maintain disease remission are needed. A 59-year-old man who underwent OLT for hepatic EPP experienced increased bilirubin and aminotransferases on postoperative day 700. Allograft biopsy demonstrated recurrent EPP. He was managed initially with plasmapheresis, hypertransfusion, and infusions of i.v. hematin. After normalization of liver tests, the hematin infusions have been given intermittently, are well tolerated, and associated with normal allograft function for nearly 2 years. This is the first case of the use of hematin given post-OLT to help achieve and maintain remission of allograft EPP disease.

A pyridoxine (B6) dietary deficiency was studied in female adult Sprague-Dawley rats by hind-limb walking-track analysis. Serum levels of pyridoxine and three metabolites were quantified by high-pressure liquid chromatography with fluorescence measurement. Morphometric analysis of the sciatic and posterior tibial nerves (from within the tarsal tunnel) was performed after 1 year on a diet deficient in vitamin B6. The B6-deficient rats developed abnormal walking-track patterns by 8 months, and these track parameters were different from age- and sex-matched normal diet control rats at the p < 0.05 level. Adding B6 at 10 parts per million to the diet then partially corrected these parameters, whereas the addition of 30 parts per million B6 corrected the abnormal pattern completely. Serum pyridoxal concentration correlated with the functional parameters, dropping from a mean of 115 mg per liter to 39.5 mg per liter (p < 0.05), and correcting with the B6 additive. Morphometric analysis demonstrated that the B6-deficient nerve from the tarsal tunnel had a decreased nerve fiber density (p < 0.001), with a normal total myelinated nerve fiber number, and an increased axon-to-myelin ratio (p < 0.003). It is concluded that a diet totally deficient in vitamin B6 results in a peripheral neuropathy.