poly·​myo·​si·​tis | \ ˌpä-lē-ˌmī-ə-ˈsī-təs How to pronounce polymyositis (audio) \

Definition of polymyositis

: inflammation of several muscles at once specifically : an inflammatory muscle disease of unknown cause that affects muscles and chiefly skeletal muscles and is characterized especially by weakness of the muscles (such as those of the shoulder, neck, or hip) closest to the trunk — see dermatomyositis

Examples of polymyositis in a Sentence

Recent Examples on the Web Estrada was diagnosed at the age of 14 with polymyositis, a disease that wastes away muscles and has no cure. Washington Post, "Sick woman campaigns for medically assisted suicide in Peru," 30 Dec. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'polymyositis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of polymyositis

1877, in the meaning defined above

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The first known use of polymyositis was in 1877

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Cite this Entry

“Polymyositis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polymyositis. Accessed 31 Oct. 2020.

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poly·​myo·​si·​tis | \ -ˌmī-ə-ˈsīt-əs How to pronounce polymyositis (audio) \

Medical Definition of polymyositis

: inflammation of several muscles at once specifically : an inflammatory disease of unknown cause that affects muscles and especially skeletal muscles, is characterized typically by weakness usually of the proximal muscles (such as those of the shoulder or pelvic girdles or of the neck), muscle and joint pain, pathological muscle changes (such as fiber degeneration or infiltration by lymphocytes), pneumonia, and cardiac abnormalities (such as arrhythmia or myocarditis) Dermatomyositis affects both children and adults, and females more often than males, whereas polymyositis is seen after the second decade of life and very rarely in childhood. — Marinos C. Dalakas, The New England Journal of Medicine, 21 Nov. 1991 — see dermatomyositis

More from Merriam-Webster on polymyositis

Britannica.com: Encyclopedia article about polymyositis

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