Table 1.

Causes of symmetrical digital gangrene

Hypercoagulable state	Primary: Antithrombin III deficiency, protein C and protein S deficiency, abnormalities of the fibrinolytic system and dysfibrinogenemias. Secondary: DIC, malignancy, pregnancy, use of oral contraceptives, myeloproliferative disorders, hyperlipidaemia, diabetes mellitus, sickle cell anaemia, polycythemia rubra vera and Waldenstrom's macroglobulinemia.
Ischaemic states	Low cardiac output, atherosclerosis, myocardial infarction.
Vasculitis	Large vessels: Polymyalgia rheumatica, Takayasu's arteritis and temporal arteritis. Medium size vessels: Buerger's disease, cutaneous vasculitis, Kawasaki disease, and polyarteritis nodosa. Small vessels: Behçet's disease, eosinophilic granulomatosis with polyangiitis, cutaneous vasculitis, Henoch Schönlein purpura, microscopic polyangiitis, granulomatosis with polyangiitis, Golfer's vasculitis and cryoglobulinemia.
Autoimmune	Systemic lupus erythematous, connective tissue disease, antiphospholipid syndrome and Raynaud's phenomenon.
Drugs	Dopamine, epinephrine and norepinephrine.
Infection-sepsis	Septic shock, leprosy.
Physical agents	Trauma, vibration, electrical injuries, burns, lightning strike, low temperature (frostbite) and high altitude.
Other causes	Congenital erythropoietic porphyria, ainhum, Lesch-Nyhan syndrome, syringomyelia and long-term tobacco smoking.

DIC, disseminated intravascular coagulation.