Manifestations cutanées révélant une cryofibrinogénémie associée à une gammapathie monoclonale

Cryofibrinogenaemia is an under-recognized cutaneous thrombotic vasculopathy that may be revealed by purpura or chronic necrotic ulcerations. We report two original cases characterized by their severity, their association with a monoclonal gammopathy and their excellent response to treatment.A 38-year-old woman was admitted for large necrotic leg ulcers appearing 1 year earlier and already investigated. Non-specific signs were seen on a previous skin biopsy and the diagnosis of a factitious disorder was considered at that time. Further investigations revealed circulating cryofibrinogen associated with IgG kappa monoclonal gammopathy without cryoglobulinaemia. Plasmapheresis followed by bortezomid-dexamethasone to treat the monoclonal gammopathy resulted in rapid and complete healing of the ulcers, militating in favour of its involvement in cryofibrinogen formation. The second patient, a 91-year-old woman, was referred to our department for acute necrotic purpura of the legs. Skin biopsy revealed leukocytoclastic vasculitis. Glomerular nephropathy with acute renal failure and multiple arterial thromboses were associated with the skin condition. The cryofibrinogen assay was positive without cryoglobulinaemia and other causes of vasculitis were ruled out. The main component was monoclonal IgG lambda. Prednisone-cyclophosphamide treatment led to complete healing of the skin lesions and to recovery from the systemic consequences of cryofibrinogen without sequelae.Routine screening for cryofibrinogen in plasma should be performed to explore cutaneous symptoms of unexplained thrombotic vasculopathy, even in the presence of a non-specific skin biopsy. Specific treatment of cryofibrinogenaemia associated monoclonal gammopathy appears to be highly effective against manifestations of cryofibrinogenaemia.