How can I differentiate between diabetic neuropathy and other causes of neuropathic pain in my patients?

To differentiate diabetic neuropathy from other causes of neuropathic pain, start with a detailed clinical history focusing on diabetes duration, glycaemic control, and symptom onset, as diabetic neuropathy typically develops after years of poorly controlled diabetes and presents with symmetrical distal sensory loss and pain, often described as burning or tingling in a stocking-glove distribution NICE NG17 Argoff et al. 2006. Conduct a thorough neurological examination assessing sensory modalities (pinprick, vibration, temperature), reflexes, and motor function; diabetic neuropathy commonly shows reduced distal sensation and diminished ankle reflexes NICE NG17 Argoff et al. 2006. Exclude other causes by considering atypical features such as asymmetry, proximal involvement, or rapid progression, which may suggest alternative diagnoses like radiculopathy, inflammatory neuropathies, or vitamin deficiencies NICE NG17. Use nerve conduction studies selectively to confirm large fibre involvement typical of diabetic neuropathy, while small fibre neuropathy may require specialised tests like skin biopsy or quantitative sensory testing, which are less commonly available in primary care NICE NG17 Javed et al. 2015. Blood tests should screen for other causes including vitamin B12 deficiency, thyroid dysfunction, and paraproteinaemia NICE NG17. The presence of diabetic microvascular complications (retinopathy, nephropathy) supports diabetic neuropathy diagnosis NICE NG17. In summary, a combination of clinical pattern recognition, targeted examination, and exclusion of other causes through history, examination, and investigations enables differentiation of diabetic neuropathy from other neuropathic pain causes NICE NG17 Argoff et al. 2006Javed et al. 2015.