High Protein and Exercise Therapy Plus Nocturnal Enteral Feeding in Juvenile-onset Pompe Disease

The research protocol will be submitted for approval to the institutional review board of Columbia University Medical Center. An attempt will be made to recruit at least 6 juvenile patients between the ages of 8 and 17, preferably who are still ambulatory. Subjects meeting all eligibility criteria will undergo a full history and physical examination, including details of age of onset of symptoms, distribution and severity of muscle weakness, muscle function, pulmonary function, and nutritional status. Subjects will undergo an electrocardiogram (ECG), spirometry, muscule strength evaluation, exercise capacity, functional muscle tests, laboratory tests, and muscle biopsy. Quality of life will be assessed via SF 36 questionnaire. Functional ability and level of handicap will be assessed by Rotterdam handicap scale. Written informed consent will be obtained from all subjects. All patients, who will have received enzyme replacement therapy (ERT) for at least 2 years, will be evaluated prior to institution of high protein nutrition and exercise therapy plus nocturnal enteral feeding (HPET + NEF)(baseline), then again at 3 months, 6 months and 12 months into treatment. The following parameters will be evaluated- * Skeletal Muscle Function * Biochemical parameters from collected blood sample Muscle Biopsy will be obtained at baseline and at 12 months. Biopsy specimens, obtained from thigh muscle at baseline and a repeat biopsy of the corresponding area of the other leg at 12 months, will be analyzed as follows:. * Histology and electron microscopy * Autophagic and lysosomal function evaluation * Body composition Body mass index (BMI), body composition, lean body mass, and fat mass will be measured at each visit by bioelectric impedance analysis using BI-101Q RJL Systems, software 3.1b