Clinical Reviews: Liver DiseasesPorphyriasScarlett, Yolanda V. M.D.; Brenner, David A. M.D. Author Information From the Department of Medicine, Division of Digestive Diseases and Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Address correspondence and reprint requests to Dr. D. A. Brenner, Department of Medicine, Division of Digestive Diseases and Nutrition, University of North Carolina at Chapel Hill, 325 Burnett-Womack Building, Campus Box 7080, Chapel Hill, NC 27599-7080. Journal of Clinical Gastroenterology: October 1998 - Volume 27 - Issue 3 - p 192-198 Buy Abstract The porphyrias are a heterogeneous group of metabolic disorders caused by genetic defects of the enzymes involved in heme biosynthesis. The diseases are characterized by excessive accumulation and excretion of porphyrin or porphyrin precursors. The disorders have been classified as cutaneous, hepatic, or neuropsychiatric according to the organ system involved. This review describes the enzymes of the heme biosynthetic pathway along with the clinical features and management of the porphyrias. © 1998 Lippincott Williams & Wilkins, Inc.