Dermatomyositis

Introduction

In this connective tissue disease commonly inflammatory and degenerative changes are found in the affected muscles and skin. It is an autoimmune disease, although the precise mechanism is unknown. What is known is that cell mediated immune cells play a role in the infiltration and inflammation of muscles and skin.

Also, there seems a cross reaction beween certain tumors and autoimmune antibodies and the muscle antigens.There may be a shared antigen that makes dermatomyositis occur more often alongside certain tumors.

Approximately 15% of men and less women with dermatomyositis have a hidden malignancy in their bodies. Dermatomyositis is more common in women than men with a ratio of 2 to 1. Sometimes a viral infection can be followed by the development of dermatomyositis. Picorna viruses have been implicated in a number of dermatomyositis cases. There are two age group peaks, one in childhood from age 5 to 15 and another peak at age 40 to 60 (Ref. 1).

Disclaimer:

This outline is only a teaching aid to patients and should stimulate you to ask the right questions when seeing your doctor. However, the responsibility of treatment stays in the hands of your doctor and you.

References:

1.The Merck Manual, 7th edition, by M. H. Beers et al., Whitehouse Station, N.J., 1999. Chapter 50.

2. WA Schmidt et al. Clin Rheumatol 2000;19(5):371-377.

3. A Sauty et al. Eur Respir J 1997 Dec;10(12):2907-2912.

4. R Queiro-Silva et al. J Rheumatol 2001 Jun;28(6):1401-1404.

5. J Wada et al. Clin Exp Immunol 2001 May;124(2):282-289.

6. Ferri: Ferri's Clinical Advisor: Instant Diagnosis and Treatment, 2004 ed., Copyright © 2004 Mosby, Inc.

7. Rakel: Conn's Current Therapy 2004, 56th ed., Copyright © 2004 Elsevier

Last Modified: Nov. 12, 2008