Polyglucosan bodies in intramuscular nerves: Association with muscle fiber denervation atrophy

Polyglucosan bodies (PB) in the intramuscular nerves have been rarely studied, and their presence particularly in subjects without neurologic disorders has been thought to be age-related. We examined, by using light and electron microscopy, 204 consecutive muscle biopsies. PB was found in 5 quadriceps intramuscular nerves (2.45% of all biopsies). All 5 quadriceps containing PB exhibited varying degrees of muscle fiber denervation atrophy with or without fiber type grouping. These quadriceps with PB, compared with the other 119 quadriceps without PB, showed a significantly greater association with muscle fiber denervation atrophy (5/5 versus 55/119; p = 0.02, by two-tailed Fisher's exact test), for which aging is not confounding. Electron microscopy identified PB in intramuscular nerve myelinated fibers along with ongoing degenerative changes. Our observation suggests that PB in intramuscular nerves may be pathologic and associated with muscle fiber denervation atrophy.