PReS-FINAL-2244: Ultrasound examination reveals typical alterations in joints of mucopolysaccharidosis (MPS) patients

Introduction Mucopolysaccharidoses (MPS) are a group of metabolic disorders caused by the absence or inadequate functioning of enzymes needed to break down glycosaminoglycans (GAG), which are essential structural elements of many tissues in the human body (bone, cartilage, cornea, skin, connective tissue). One of the main features of several of the mucopolysaccharidoses is bone damage and remodeling, along with synovial thickening, clinically manifested as coarse facies, thickened and widened bones on x-rays, and joint contractures of varying severity. These signs and symptoms can be the presenting features of the disease, and lead to clinical diagnosis when properly interpreted. The aversion to unnecessary exposure of patients to radiation and the question of which bones to examine by x-ray is understandable. MPS patients are additionally at a much higher risk of severe sequelae from anesthesia, making MRI examination more difficult. Therefore, the question of the best method by which to measure bone and joint involvement and progression in patients with established disease is a difficult one.