Clinical Images: Groove sign: heeding clue to eosinophilic fasciitis

The patient, a 71-year-old woman, presented with a five-month history of progressively worsening painful skin tightening and swelling of her extremities. Consent was obtained directly from the patient. A physical examination revealed bilateral edema in the forearms and legs, with erythema and skin induration. Both forearms showed a linear depression in the skin parallel to the course of the superficial veins, more obvious on raising the arm, which was consistent with the “groove sign” (Figures A–B, arrows). The “groove sign” was also observed on the thighs (Figure C, arrow). Knee contractures were also noted. She had received glucocorticoid treatment for possible nodular erythema, but the symptoms progressed. A laboratory analysis was notable for an elevated absolute eosinophil count of 1.79 × 109/L (reference range <0.52 × 109/L) and an erythrocyte sedimentation rate of 40 mm/h. The creatinine kinase level was within normal limits, and the result of an antinuclear antibody test was negative. Magnetic resonance imaging of the lower limbs showed enhancement of superficial (D, asterisk) and deep (D, arrow) fasciitis. A fascial biopsy of the right lower limb confirmed fasciitis with infiltration of eosinophils (E). A diagnosis of eosinophilic fasciitis (EF) was made. Therapy was initiated with glucocorticoids, cyclophosphamide, and tocilizumab, and the symptoms were improved. EF (previously known as Shulman disease) is a rare, acquired, fibrosing disease, typified by erythema, edema, and induration of the bilateral extremities.1 A characteristic finding is the groove sign, which is a linear depression along the course of superficial veins accentuated by limb elevation due to inward tethering of the skin by fascial fibrosis.2 Joint contractures occur in 50% to 56% of patients.3 Early diagnosis of EF is crucial to prevent aggressive fibrosis and joint contracture. Supported by Shanghai Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine (grant ynhg202115) . Disclosure form Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.