The nerve biopsy can help to distinguish axonal from demyelinating polyneuropathy, when other tests are inconclusive. It should be chosen a nerve that supplies the affected area. In polyneuropathy due to a vasculitis, the sample should include skin; thereby the chances of finding a characteristic vascular anomaly, is improved. If the biopsy that nerve endings have been lost, a punch biopsy of the skin may assist in the diagnosis of polyneuropathy of the small fibers.
Nerve and muscle biopsy be performed generally simultaneously. The nerve biopsy can help to distinguish axonal from demyelinating polyneuropathy, when other tests are inconclusive. It should be chosen a nerve that supplies the affected area. In polyneuropathy due to a vasculitis, the sample should include skin; thereby the chances of finding a characteristic vascular anomaly, is improved. If the biopsy that nerve endings have been lost, a punch biopsy of the skin may assist in the diagnosis of polyneuropathy of the small fibers. A muscle biopsy can confirm the presence of myopathy.
