The Differential Diagnosis of Systemic Sclerosis

Alan Tyndall; Susanna Fistarol


Curr Opin Rheumatol. 2013;25(6):692-699. 

In This Article

Eosinophilic Fasciitis (Shulman's Syndrome)

First described in the mid-1970s by Shulman,[5] eosinophilic fasciitis typically affects 40–50-year-old adults with symmetrical distal forearm and calf skin induration, often sparing the face and fingers. However, flexor tenosynovitis of the hands may produce the nonspecific 'prayer sign'. Eosinophilic fasciitis may have an acute to subacute onset following trauma or extreme physical effort[6] and be associated with profound fatigue, myalgias, arthralgias and stiffness. Acute-phase reactants are often elevated and although hypergammaglobulinaemia is common, monoclonal gammopathy is absent. The deep skin is oedematous and tethered, though in contrast to SSc, the superficial skin is often still able to be wrinkled by pinching. The tethering of the dermis to the fascia and muscle layers results in skin puckering and venous furrowing, ' the groove sign' (Fig. 1). The exact pathophysiology is unknown and suggestions of triggers such as Borrelia burgdorferi, toxic oil or L-tryptophan have been sporadic and inconsistent. Peripheral eosinophilia may be absent in 20% of untreated cases, but adequate biopsies should show eosinophilic and mononuclear infiltrates along the fascia, though this may rapidly disappear after glucocorticoid exposure. Increased mucin deposition is not present. Increased tissue macrophages, cytotoxic CD8 T cells, TGFβ and interleukin 5 typical of a fibrogenic phenotype are seen in biopsies which should always include deep fascia and muscle. Biopsy is best guided by an MRI with contrast which shows a typical hyperintense signal on fluid-sensitive sequences and with contrast medium (Fig. 2).[7] Raynaud's phenomenon, SSc type capillaroscopy changes and antinuclear antibodies as well as internal organ involvement are absent. Although rarely paraneoplastic, the presence of cytopenias may signal an underlying haematological disorders such as haemolytic anaemia,[8] pure red cell aplasia, myelodysplasia, lymphoma[9] or multiple myeloma.[10] Treatment consists of glucocorticosteroid in high, for example, 1 mg/kg body weight/day, doses tapering to moderate maintenance doses which may be required over several months to years. Refractory cases should be reviewed regarding the underlying malignancy or alternative diagnoses, and then may require addition of methotrexate, mycophenolate mofetil or other immunosuppressive agents. Ultraviolet light 1 (UVA-1) phototherapy may be an additional treatment. Eventually, complete resolution is to be expected in most cases. Poor prognostic features include paediatric age of onset, morphea lesions and trunk involvement.[11]

Figure 1.

The forearm of a 30-year-old man with eosinophilic fasciitis showing venous furrowing or 'groove sign' (arrow).

Figure 2.

Gadolinium-enhanced T1-weighted [a: repetition time (TR) 650, echo time (TE) 10] and T2-weighted (b: TR 2930, TE 90) MR images of the bilateral proximal thighs. Note the marked enhancement in the muscle margin because of biopsy-proven inflammation of the fascia and fatty tissues. Reproduced with permission,[7] by courtesy of Lippincott, Williams and Wilkins.