Bone/joint abnormalities in children/adolescents: A screening protocol for mucopolysaccharidosis

• Published in: Molecular genetics and metabolism 2019-02, Vol.126 (2), p.S74-S74
• Main Authors: Horovitz, Dafne D.G., Barth, Anneliese L., Barros Mendes, Pedro H., Gonzaga, Mariana Q.G., Chisté, Yuri L., Medeiros, Rommel B., Oliveira, Maria L., Scalco, Fernanda B.
• Format: Article
• Language: English
• ISSN: 1096-7192; 1096-7206
• DOI: 10.1016/j.ymgme.2018.12.179

Mucopolysaccharidoses (MPS) are under-diagnosed, especially milder forms. A screening protocol was tested at the National Institute of Orthopedics in Rio de Janeiro - Brazil. Patients were selected from Pediatric Orthopedics, Spine and Hand clinics. Inclusion criteria were age under 18, suspected Legg-Calve-Perthes disease, scoliosis, kyphosis, genu valgum, trigger finger, carpal tunnel syndrome, atypical epiphyseal dysplasia and short stature, associated or not to dysostosis exclusion criteria were confirmed diagnosis of other genetic bone disease and chronic disorders with bone abnormalities. Patients were clinically evaluated to identify other signs / symptoms of MPS, with information on infections, surgeries and other morbidities, other specialists seen and family history. Selected patients underwent hand/wrist and lateral lumbar spine X-rays and provided urine sample for GAG analyses. Clinical forms, X-rays and urinary results were reviewed by a genetics team familiar with MPS. Patients with X-ray abnormalities suggestive of MPS and/or abnormal urinary analysis were selected for re-evaluation by genetics and blood collection for enzyme activity studies. If necessary, additional exams (complete skeletal X-rays, echocardiogram or others) were ordered. From November 2015 to October 2017, 1119 pediatric patients were evaluated and 55 selected for X-rays and urinary GAG analyses. Two did not complete the exams and were excluded. In the remaining 53, MPS was ruled out in 51 after comprehensive clinical evaluation, more complete imaging and enzyme activity studies in selected cases. Two patients with short stature, genu valgum, oar shaped ribs, abnormal spine and metacarpals had normal urinary GAGs enzyme activity studies will be ordered. So far, no MPS diagnosis was confirmed. We diagnosed a spondilo-epiphyseal dysplasia and an epiphyseal dysplasia. Despite not having MPS confirmed, we believe the protocol can be effective, although In future studies isolated scoliosis will no longer be an inclusion criterion. Acknowledgements: Biomarin - financial support Rede MPS Brasil - enzyme studies.