Neuropathy in elderly: lessons learnt from nerve biopsy

OBJECTIVE: To study the utility of nerve biopsy in providing diagnostic, therapeutic or prognostic information that aid in clinical management in elderly subjects with peripheral neuropathy. METHODS: Clinico-pathological data of 100 elderly subjects aged 65 and above with peripheral neuropathy who underwent nerve biopsy in the last decade (2002-2011) was reviewed. RESULTS: The study included 100 subjects (M:F 78:22). Mean age at biopsy and symptom duration was 69.62±4.8 years and 24.17±40.4 months, respectively. The most common pattern of was distal symmetric sensorimotor polyneuropathy (35%), followed by multiple mononeuropathy (29%) and asymmetric sensorimotor neuropathy (15%). The nerve biopsy was 'diagnostic' in 24%, (definite vasculitis in 12, leprosy in 10 and acute inflammatory demyelinating polyradiculoneuropathy in 2) and proved 'essential' or 'helpful' in therapeutic management in 81% subjects. In 60 (60%) patients, where a pre-biopsy aetiological diagnosis could be arrived at based on the available data, nerve biopsy confirmed the diagnosis in 29 of 60 (48.3%), and offered a new diagnosis in 25 (41.7%). A higher yield of biopsy was noted in subjects with asymmetric/multiple mononeuropathy compared with symmetric neuropathies (32.7% versus 17.7%). In 40 (40%) patients without a pre-biopsy aetiological diagnosis, nerve biopsy was 'essential' in 7 of 40 (17.5%) as it provided a definitive diagnosis (definite vasculitis: 5, leprosy: 2), and 'helpful' in 21 of 40 (52.5%) (ischaemic neuropathy: 10, possible vasculitis: 9, probable vasculitis: 2). CONCLUSION: Nerve biopsy aided in the detection of potentially treatable disorders and influenced patient management in a significant proportion of elderly subjects with peripheral neuropathy (81%), particularly in subset with undiagnosed neuropathies confirming that it's a useful tool in diagnosis of neuropathy in the elderly. With minor differences, the aetiological profile in our biopsied neuropathic elderly subjects may reflect the findings in other similar cohorts.