Ischaemic monomelic neuropathy in a non-diabetic patient following creation of an upper limb arteriovenous fistula

The incidence of end-stage renal disease (ESRD) in Australia is estimated at 0.05% of the population. The majority of these patients will choose haemodialysis as the preferred form of renal replacement therapy, requiring creation of an arteriovenous fistula (AVF). The subsequent haemodynamic disturbance can lead to neurological or ischaemic problems. The reported frequency of such complications varies between 1 and 10% and is most common following proximal procedures involving the upper limb. Ischaemic neuropathy describes damage to a peripheral nerve caused by compromise of blood supply. The first description of such an injury following formation of an arteriovenous shunt was made by Bolton et al. 1, although the term ischaemic monomelic neuropathy (IMN) was coined by Wilbourn et al. 2. He described a type of ischaemic neuropathy associated with interference of a major limb artery resulting in multiple, distal, axonal-loss mononeuropathies. The clinical features of IMN are typically sensorimotor with dysaesthetic sensory symptoms in the hand and forearm and associated weakness or paralysis of muscles in the same area 3. The syndrome develops quickly (typically within hours) of AVF formation. There is no description of IMN precipitated by distal forearm procedure. It is distinct from steal syndrome, the most commonly recognized complication of vascular access surgery 4. In the latter, the onset is more insidious, there are typically signs of skin and muscle infarction and other trophic changes, and the degree of ischaemia is generally more profound. IMN has been reported exclusively in patients with diabetes mellitus (DM), who often have pre-existing neuropathy and concomitant accelerated atherosclerosis. Brachiocephalic fistulae are most commonly associated with ischaemic complications; anatomically the brachial artery provides the only arterial inflow to the distal arm and in the absence of collateral blood vessels the risk of ischaemia is increased. In addition, the antecubital area is the watershed area of vasae nervorum for the three nerves supplying the upper limb 5. We report on the first documented case in a non-diabetic individual.