Blue toe syndrome

Blue toe syndrome (BTS) is not an uncommon referral, with vascular services often being the first port of call from primary care or the emergency department setting. It is a condition which is often overlooked, misdiagnosed or falsely labelled in the wider medical setting. Nevertheless, it warrants a thorough history, examination and assessment due to its potential implications. BTS was first named by Karmody et al in 1976,1,2 with the perceived pathophysiology being that of a vascular aetiology. As its name suggests, the basis of its presentation is the finding of blue or purple discolouration of one or more toes, in one or both feet, without a clearly recognised underlying factor.3,4 It typically occurs in the absence of any oblivious trauma, cold-induced lesion or disorders that induce generalised cyanosis.4