Background. At the beginning the antiphospholipid antibodies syndrome was associated with systemic lupus erythematosus. But since 1988 it has become a sole entity. Its current definition is based on the criteria established in 1999 by Sapporo and consists of associating the clinical criteria of thrombosis of arteries or peripheral veins and of miscarriage of pregnancy with the biological criteria. Either anti-cardiolipin antibodies or lupus anticoagulant must be present. Anti-phosphatidylethanolamine antibodies are not included in the Sapporo criteria. Case report. A non smoking, 43 year-old man showed a clinical manifestation of livedo on the thighs, and left knee and foot, associated with a rapidly extending cutaneous necrosis on the left toes. One year earlier his right leg was amputated up to half of the calf following distal gangrene. The gangrene was consecutive to a stent implantation after a significant stenosis of the right superficial femoral artery. The etiological investigations revealed neither thrombophily nor cholesterol embolism nor vasculitis. No sign of underlying neoplasia could be found. These clinical symptoms as well as the anamnesis were strongly suggestive of an antiphospholipid antibodies syndrome. The immunological dosages revealed isolated positive anti-phosphatidylethanolamine antibodies,persistent six weeks later. Discussion. Several cases of clinical manifestations of the antiphospho lipid antibodies syndrome have been described, without any anti-cardiolipin antibodies or lupus anticoagulant, but with presence of anti-phosphatidylethanolamine antibodies. In cases of these strong evocative symptoms but no evidence of the classical biological Sapporo criteria,these antibodies should be systematically searched for. Background. At the beginning the antiphospholipid antibodies syndrome was associated with systemic lupus erythematosus. But since 1988 it has become a sole entity. Its current definition is based on the criteria established in 1999 by Sapporo and consists of associating the clinical criteria of thrombosis of arteries or peripheral veins and of miscarriage of pregnancy with the biological criteria. Either anti-cardiolipin antibodies or lupus anticoagulant must be present. Anti-phosphatidylethanolamine antibodies are not included in the Sapporo criteria. Case report. A non smoking, 43 year-old man showed a clinical manifestation of livedo on the thighs, and left knee and foot, associated with a rapidly extending cutaneous necrosis on the left toes. One year earlier his right leg was amputated up to half of the calf following distal gangrene. The gangrene was consecutive to a stent implantation after a significant stenosis of the right superficial femoral artery. The etiological investiga The clinical symptoms as well as the anamnesis were strongly suggestive of an antiphospholipid antibodies syndrome. The immunological dosages revealed isolated positive anti-phosphatidylethanolamine antibodies, persistent six weeks later. Discussion. Several cases of clinical manifestations of the antiphospho lipid antibodies syndrome have been described, without any anti-cardiolipin antibodies or lupus anticoagulant, but with presence of anti-phosphatidylethanolamine antibodies. In cases of strong evocative symptoms but no evidence of the The classical biological Sapporo criteria, these antibodies should be systematically searched for.