Inflammatory myopathy

Inflammatory myopathy
Classification and external resources
Micrograph of dermatomyositis, a type of inflammatory myopathy. Muscle biopsy. H&E stain.
ICD-10	M33, G72.4
ICD-9	359.6, 710.3-710.4
DiseasesDB	29473
MeSH	D009220

Inflammatory myopathy is a form of myopathy that involves inflammation of the muscle.

Inflammatory myopathy is generally synonymous to the term dermatopolymyositis, which, according to ICD-10 encompasses three related diseases: polymyositis, dermatomyositis, and inclusion-body myositis.^[1][2]

Diagnosis

Inflammatory myopathy can be associated with increased ESR and creatine kinase.

Dermatopolymyositis can be associated with several types of autoantibodies:

• Anti-Jo1 antibodies,^[3] which is associated with a more abrupt onset of fever, cracked hands, Raynaud's phenomenon, interstitial lung disease, arthritis, and a poor response to therapy.^[4] Anti-Jo1 antibodies are a type of anti-nuclear antibody.^[5][6] It has histidine-tRNA ligase as a target.
• Anti-signal recognition particle antibodies (anti-SRP),^[7] which are targeting signal recognition particle (SRP). Anti-SRP antibodies are mainly associated with, but are not very specific for, polymyositis.^[7] For individuals with polymyositis, the presence of anti-SRP antibodies are associated with more prominent muscle weakness and atrophy,^[7] and more cardiac manifestations.^[4]
• Anti-Mi-2 antibodies, which are associated with a better prognosis.^[4]

Treatment

Treatment may involve steroids or other antiinflammatories.

See also

• Myositis

References

1. ^ ICD-10 > M33: Dermatopolymyositis
2. ^ Phillip R. J. Barnes; David Hilton-Jones (2003). Myopathies in Clinical Practice. Informa Health Care. pp. 85–. ISBN 9781899066711. http://books.google.com/?id=4Qs2e4rPM4kC&pg=PA85. Retrieved 26 June 2010. 
3. ^ Kalenian M, Zweiman B (March 1997). "Inflammatory myopathy, bronchiolitis obliterans/organizing pneumonia, and anti-Jo-1 antibodies--an interesting association". Clinical and diagnostic laboratory immunology 4 (2): 236–40. PMC 170510. PMID 9067664. http://cvi.asm.org/cgi/pmidlookup?view=long&pmid=9067664. 
4. ^ ^{a b c} Page 254 in: Elizabeth D Agabegi; Agabegi, Steven S. (2008). Step-Up to Medicine (Step-Up Series). Hagerstwon, MD: Lippincott Williams & Wilkins. ISBN 0-7817-7153-6. 
5. ^ Gutiérrez-Ramos R, Gonzalez-Díaz V, Pacheco-Tovar MG, López-Luna A, Avalos-Díaz E, Herrera-Esparza R (2008). "A dermatomyositis and scleroderma overlap syndrome with a remarkable high titer of anti-exosome antibodies". Reumatismo 60 (4): 296–300. PMID 19132155. http://www.reumatismo.org/admin/filesArticoli/60-4-296.pdf. 
6. ^ Zold E, Szodoray P, Gaal J, et al. (2008). "Vitamin D deficiency in undifferentiated connective tissue disease". Arthritis Res. Ther. 10 (5): R123. doi:10.1186/ar2533. PMC 2592813. PMID 18928561. http://arthritis-research.com/content/10/5/R123. 
7. ^ ^{a b c} Kao, A. H.; Lacomis, D.; Lucas, M.; Fertig, N.; Oddis, C. V. (2004). "Anti-signal recognition particle autoantibody in patients with and patients without idiopathic inflammatory myopathy". Arthritis & Rheumatism 50 (1): 209–215. doi:10.1002/art.11484. PMID 14730618.  edit