PreambleThis guideline is intended for use by physicians. It describes preferable up-to-date approaches to the diagnosis and treatment of patients with Wilson disease. As their purpose is to direct patient care, these guidelines should not be considered inflexible mandates. They have been developed in a manner consistent with the American Association for the Study of Liver Diseases Policy Statement on Development and Use of Practice Guidelines.These guidelines provide data-supported approaches to the diagnosis and management of patients with Wilson disease. They are based on, first, broad-based review of the published literature in pediatrics and medicine including Medline searches on hepatolenticular degeneration and related subjects; and second, 40 accumulated years of personal experience of the authors. In order to standardize recommendations as much as possible, each has been characterized with Roman numerals I through IV to indicate the quality of evidence on which the recommendation is based (Table 1). 1 A significant problem with the literature on Wilson disease is that patients are sufficiently rare to preclude large cohort studies or randomized controlled trials; moreover, most treatment modalities were developed at a time when conventions for drug assessment were less stringent than currently.