@article {Moutinho-Pereirae250389, author = {Sara Moutinho-Pereira and Eurico Morais-de-S{\'a} and Helena Greenfield and P Ricardo Pereira}, title = {Systemic sclerosis in a patient with muscle dystrophy}, volume = {15}, number = {9}, elocation-id = {e250389}, year = {2022}, doi = {10.1136/bcr-2022-250389}, publisher = {BMJ Specialist Journals}, abstract = {Systemic sclerosis is an autoimmune disease that can result in lung fibrosis, and is strongly associated with the presence of serum anti-topoisomerase-I autoantibodies. A young man with genetic muscular dystrophy caused by titin-cap/telethonin (TCAP) gene mutation, developed a severe restrictive lung disease due to a fibrosing interstitial pneumonia secondary to systemic sclerosis with positive anti-topoisomerase-I antibodies. Using amino acid sequence alignment and protein structure modelling, we found that mutant telethonin exposes an amino acid sequence with significant homology to an immunodominant site of topoisomerase-I. Abnormal telethonin results in a loss of integrity of the sarcomere structure, which might result in rhabdomyolysis and abnormal protein exposure to the immune system. Our preliminary analysis suggests a possible role for mutant sarcomere protein telethonin as an immunogenic target recognised by anti-topoisomerase-I antibodies, which could explain the development of systemic sclerosis in this particular patient.}, URL = {https://casereports.bmj.com/content/15/9/e250389}, eprint = {https://casereports.bmj.com/content/15/9/e250389.full.pdf}, journal = {BMJ Case Reports CP} }