Skin biopsy and staining the specimens with immuno-reactive markers has been proven to be a useful method to demonstrate the pathologic status of small nerve fibers. Quantification of intraepidermal nerve fiber density using anti-protein gene product 9.5 antibody is a standard method to diagnose small fiber neuropathy. Skin biopsy also makes it possible to differentiate the nerve fibers according to their function by using different markers. Quantification of dermal structures with different types of nerve fibers could reveal the pathophysiologic mechanism of the disease state.
