Progress Report by Dr. Laforêt, MD, PhD, Raymond Poincaré University Hospital, Garches, France

Project: Improving characterization of neuromuscular involvement in adults with cystinosis.

Beside the consequences of renal failure, the long-term prognosis of cystinosis seems to be related to neuromuscular complications. The main manifestations of neuromuscular involvement have been described in previous studies, emphasizing on hand muscle weakness, respiratory insufficiency, and swallowing impairment. However, the long-term consequences and natural history of these symptoms remain an important issue. We propose to explore thoroughly the neuromuscular complications of cystinosis, focusing on skeletal and respiratory muscle weakness, in a well-characterized cohort of patients followed in a French reference center.

Twenty patients will be recruited and evaluated in Garches neuromuscular center in order to assess muscle strength and function with standardized tools. Whole body muscle MRI will be performed in order to better describe the pattern of skeletal muscle involvement. Respiratory muscle damage will be investigated with specific pulmonary function explorations and a systematic evaluation of its consequences on breathing efficiency.

We expect this study to improve the knowledge of neuromuscular manifestations of cystinosis. Increased awareness and characterization of these potentially disabling symptoms should improve the care of the patients by leading to a better and more specific management of these complications. This study should also help to identify outcomes measures which could be used in future clinical trials to assess the response of skeletal muscles to innovative therapies.

Read the General Information on the Study and the Study Lay Abstract.