Homozygous Factor V Leiden Thrombophilia in a Patient With Histologically Confirmed Thromboangiitis Obliterans

Thromboangiitis obliterans (TAO) is a vasculitis characterised by segmental occlusions of small to medium-sized arteries and superficial veins, and a curious predilection for young male smokers. The exact aetiology remains unknown. Current theories postulate it is an autoimmune endarteritis, triggered by some constituent of tobacco and occurring in genetically susceptible individuals. The disease can pose a diagnostic challenge, requiring a high degree of clinical suspicion, particularly in male smokers aged between 20-45 presenting with peripheral ischaemia. The fundamental principle of management is absolute tobacco abstinence. In this article, we report the case of a 27-year-old man who presented with infected, chronic wounds of his upper and lower extremities. He was initially treated with antibiotics and surgical debridement. Unfortunately he went on to develop a protracted course of complications due to poor wound healing ultimately leading to amputation of several digits. A diagnosis of TAO was suspected, and this was later confirmed histologically. Incidentally and of note, the patient was also found to be homozygous for factor V Leiden. An association between TAO and hypercoagulable states, specifically heterozygous factor V Leiden mutation, has been previously described. It is unclear if a synergistic effect between TAO and homozygosity for factor V Leiden may have contributed to the severity and unremitting nature of our patient’s symptoms. We present this case in order to highlight the importance of early recognition of the condition and the need to offer comprehensive smoking cessation support in order to prevent amputation and other complications of poor wound healing.