An In-Depth Analysis of Our Myositis Cohort Following the Example of the EuroMyositis Registry

Stylianos Tomaras* and Jörn Kekow

An In-Depth Analysis of Our Myositis Cohort Following the Example of the Euro Myositis Registry

Myositis is a rare and very heterogeneous autoimmune inflammatory disease,
that causes muscle weakness.
Because of the disease complexity within individuals and the variety of extra
musculoskeletal manifestations, the preferred term is “idiopathic
inflammatory myopathy” (IIM) over “myositis”.

IIM includes dermatomyositis, polymyositis, inclusion body
myositis and autoimmune necrotizing myopathy. Overlap myositis is a new form of
IIM associated with concomitant features of mixed connective
tissue disorders.

Ant synthetase syndrome is not universally accepted as a distinct entity,
but clearly, the frequency of interstitial
lung disease and arthritis differs from that of other IIM forms.

Many publications over the past five to ten years indicate
high research activity on IIM, including the new European
League Against Rheumatism/American College of Rheumatology
(EULAR/ACR) classification criteria,
the first international Euro Myositis registry,
standardized tools to measure disease activity
and damage by the International Myositis Assessment and Clinical
Studies Group (IMACS) and large international genetic
epidemiological studies such as the myositis genetics consortium (MYOGEN).

The original Bohan and Peter diagnostic criteria, published in 1975,
are still widely used and include characteristic clinical findings
of the skin and muscles, elevated muscle enzymes,
muscle biopsy, and electromyography (EMG),
and most importantly, they provide exclusion criteria to eliminate IIM mimics.

At that time, the steroid-resistant form of inclusion body myositis
was not known. Little was also known of specific histopathological
findings expected to be found in different subsets of myositis
or of myositis-specific and myositis-associated antibodies.

Osteol Rheumatol Open J. 2020; 1(1): 51-60. doi: 10.17140/ORHOJ-1-114