Treatment Guidelines for Pompe Disease: A South European Perspective

Abstract

Pompe disease is a rare lysosomal disorder of muscle glycogen metabolism due to -glucosidase (acid maltase) eficiency. The prevalence of the disease is estimated to be 1:40,000. The diagnosis is based on the identification of the specific biochemical defect and has to be confirmed by molecular genetic analysis. Since 2006, enzyme replacement therapy (ERT) for Pompe disease has been available in Southern Europe. Several countries in Southern Europe are allowed, once the diagnosis is confirmed, to perform ERT and its costs are fully supported by the Ministries of Health. For example, to our knowledge, either in Portugal or Italy, the drug reimbursement is based on a specific treatment programme which removes those costs from the hospital budget. Since 2006, AIFA (Agenzia Italiana del Farmaco) has approved alglucosidase(Myozyme) for the treatment of Pompe disease patients in Italy, either for infantile or late-onset patients. Authorisation to treat patients with ERT has to be given by a centre specialising in rare diseases. This centre must assess the diagnosis of Pompe disease with absolute certainty before starting treatment. In 2008, a group of leading Italian Pompe disease researchers reviewed, from a multidisciplinary point of view, the current practices in diagnosis, management and treatment of Pompe disease. The main criteria for starting ERT ncludes: (1) confirmed diagnosis; (2) symptoms and clinical signs of muscle weakness; (3) in cases of asymptomatic yperCKaemia, a 6-month follow up has been suggested in an attempt to monitor possible clinically relevant hanges suggesting treatment. In summary, our standard protocol mainly includes evaluation of muscle strength, respiratory assessment and keletal muscle MRI. We have studied over 80 patients treated with ERT coming from 18 different Italian centres ccording to this protocol. In a recent meeting on Pompe disease held in the Netherlands, researchers showed great interest in trying to ssess new criteria for early diagnosis of Pompe disease. In our opinion, there is an emerging role for neuroimaging based on new quantitative techniques (more precise valuation of muscle fat fraction), that should allow an earlier detection of muscle damage in Pompe patients and consequent early start of ERT.