Pattern Recognition Approach to Neuropathy and Neuronopathy.

Neuropathic disorders encompass those that affect the neuron's cell body or neuronopathies, those affecting the peripheral processes, which consist of radiculopathy, plexopathy, or peripheral neuropathy and at times a combination. Before laboratory tests are ordered, the clinician should ask 7 key questions. Based on information obtained from the history and neurologic examination and the answers to these questions, a patient can be placed in 11 patterns. Each of these patterns leads to a narrower list for differential diagnosis. Once a particular pattern is recognized, further laboratory studies can be performed to confirm the clinical impression.