Eosinophilic fasciitis associated with myositis

Eosinophilic fasciitis (Shulman disease) with clinical, imaging and pathological correlation

Eosinophilic fasciitis (EF) is a rare subacute fibrosing disorder of unknown aetiology, characterised by thickening of the muscular fascia and subcutaneous tissue, leading to swelling of limbs and trunk and sparing fingers and toes. Eosinophilic infiltration and degranulation may prompt tissue damage and consequent fibrosis due to the accumulation of collagen and extracellular matrix proteins. MRI is the best imaging modality for diagnosis, depicting fascial thickening and enhancement. MRI may also have a significant role in excluding alternative diagnosis and guiding the skin-muscle biopsy.We report a case of EF with clinical and pathological correlation, highlighting the diagnostic value of MRI for early diagnosis and further treatment.

Whole-body MRI and pathological findings in adult patients with myopathies

Magnetic resonance imaging (MRI) is considered the most sensitive and specific imaging technique for the detection of muscle diseases related to myopathies. Since 2008, the use of whole-body MRI (WBMRI) to evaluate myopathies has improved due to technical advances such as rolling table platform and parallel imaging, which enable rapid assessment of the entire musculoskeletal system with high-quality images. WBMRI protocols should include T1-weighted and short-tau inversion recovery (STIR), which provide the basic pulse sequences for studying myopathies, in order to detect fatty infiltration/muscle atrophy and muscle edema, respectively. High signal intensity in T1-weighted images shows chronic disease with fatty infiltration, whereas high signal intensity in STIR indicates an acute stage with muscle edema. Additional sequences such as diffusion-weighted imaging (DWI) can be readily incorporated into routine WBMRI study protocols. Contrast-enhanced sequences have not been done. This article reviews WBMRI as an imaging method to evaluate different myopathies (idiopathic inflammatory, dystrophic, non-dystrophic, metabolic, and channelopathies). WBMRI provides a comprehensive estimate of the total burden with a single study, seeking specific distribution patterns, including clinically silent involvement of muscle areas. Furthermore, WBMRI may help to select the "target muscle area" for biopsy during patient follow-up. It may be also be used to detect related and non-related pathological conditions, such as tumors.

Focal Eosinophilic Myositis of the Hand Presenting as a Refractory Pyogenic Infection

Eosinophilic myositis is a rare disorder in which eosinophils infiltrate muscle and supporting connective tissue structures. The disorder can be localized or diffuse, and it may be associated with various systemic features resembling autoimmune disease. Focal eosinophilic myositis is the most limited form of eosinophilic myositis, for which muscle involvement is generally limited to the lower extremity. We report on a rare case of focal eosinophilic myositis of the interosseous muscles of the hand, which presented as a refractory, pyogenic hand infection.

Eosinophilic fasciitis with subjacent myositis

INTRODUCTION

Eosinophilic fasciitis (EF) is a rare disorder that can present with muscle symptoms that mimic other neuromuscular diseases.

METHODS

We report the case of a 43-year-old woman with chronic muscle aches, tightness, and stiffness with hypertrophied, well-defined muscles despite physical inactivity, and thickened skin with reduced elasticity and discoloration.

RESULTS

Except for mild peripheral eosinophilia, laboratory studies, including blood count, electrolytes, paraneoplastic panel, muscle enzymes, thyroid function, and serum protein electrophoresis, were normal. Nerve conduction studies and needle electromyography were normal. Magnetic resonance imaging of the thighs demonstrated superficial and deep fascial thickening with T2 hyperintensity and post-gadolinium enhancement. Fascial and muscle biopsy demonstrated an inflammatory exudate in the perimysium and endomysium with fragmented perimysial connective tissue and thickened, inflamed fascia. EF was diagnosed. The patient was treated with methotrexate and prednisone followed by improvement of muscle stiffness and tightness.

CONCLUSION

EF should be considered when patients present with muscle pain or enlarged muscles. Muscle Nerve 56: 525-529, 2017.