Groove sign in eosinophilic fasciitis

A 33‐year‐old man presented with a four‐month history of polyarthralgia, cutaneous oedema and induration of extremities after swimming. Linear depressions along superficial veins were seen on the forearms and shins, better visualised with elevation of the limbs, consistent with the groove sign (Figure, A and B). Laboratory tests revealed peripheral eosinophilia, elevated C‐reactive protein and hypergammaglobulinaemia. Biopsy revealed myofascial thickening with infiltration by multiple inflammatory cells, suggesting eosinophilic fasciitis. After six months of oral corticosteroids, cutaneous swelling and eosinophilia resolved, but the groove sign was still present at follow‐up 16 years later.

Eosinophilic fasciitis is a rare chronic scleroderma‐like syndrome, characterised by cutaneous induration, eosinophilia, hypergammaglobulinaemia and elevated inflammatory markers.1 About 10% of patients with eosinophilic fasciitis have haematological disorders, and hypergammaglobulinaemia may be predictive.2 Groove sign is characteristic of eosinophilic fasciitis, contributing to early diagnosis. The epidermis and upper dermis are spared from fibrosis, whereas the connective tissue surrounding veins is immovable, so when lifting the limbs, peripheral venous pressure decreases and the superficial skin is tethered inwards.3