Check nerve conduction studies, electromyography.
Check B12 level, complete blood count, serum protein electrophoresis, erythrocyte sedimentation rate, antinuclear antigen (ANA) rheumatoid factor, fasting glucose, BUN, thyroid-stimulating hormone, urine heavy metal screen.
Check HIV titer, Lyme titer, and chest X-ray.
Consider nerve biopsy.
| Results suggest axonal disorder? | Yes  |
|
| Results suggest demyelinating disorder? | Yes No |
|