Diagnostic work-up in peripheral neuropathy:: an analysis of 171 cases

This study was set up to evaluate retrospectively the efficacy of a standard diagnostic procedure, including noninvasive and invasive (spinal tap, nerve/muscle biopsy) investigations, in the diagnosis of peripheral neuropathy. The medical records of 171 in-patients with the final diagnosis of peripheral neuropathy of determined or undetermined cause were reviewed and each individual diagnostic work-up was analysed. Basic investigations included the patient's history, a clinical examination and basic laboratory tests. Depending on the individual presentation, course, and severity, further noninvasive and invasive examinations were added according to the department's standard diagnostic procedure. The aetiology could be clarified in 124 patients (73%) and remained unclear in 47 cases. Excluding cases with acute and chronic inflammatory polyneuropathy (n=14), the number of idiopathic peripheral neuropathies dropped to 33. Non-invasive investigations were sufficient to reveal the underlying aetiology in 114 cases (83 %). It is concluded that, with the application of a standard procedure for the diagnosis of peripheral neuropathy, the aetiology can be clarified in 81% of patients. In the other 19% of patients the aetiology remains idiopathic. In the majority of cases, noninvasive investigations were sufficient for diagnosis.