This is an observational registry study intended to document the course of Lysosomal Acid Lipase Deficiency (LALD), in order to further understand the disease, its progression, which treatments are effective, and any related complications. As an observational study, no additional study visits - outside of subjects usual Metabolism clinic visit - are required. Eligible patients will be asked to sign an informed consent form prior to enrollment and will periodically have the option of completing questionnaires about their quality of life.