We describe a case of adult polyglucosan body disease with characteristic clinical symptoms of peripheral neuropathy, upper motor neuron signs, and bowel and bladder dysfunction. Sural nerve biopsy revealed diagnostic intra-axonal polyglucosan bodies. On electron microscopic examination, the inclusions were located mainly within myelinated nerve fibers and consisted of branched filaments that were 6 to 8 nm wide. The diagnosis of adult polyglucosan body disease was confirmed by a skin biopsy from the axilla showing similar inclusions in myoepithelial cells of apocrine glands. This report provides additional evidence that skin biopsy, to date advocated by a single case report only, may be a less invasive and simpler diagnostic alternative to sural nerve or brain biopsies.