Adult polyglucosan body disease (APBD) presenting with a bulbocerebellar syndrome

Adult polyglucosan body disease (APBD) is a rare clinico-pathologic entity characterized by upper and lower motor neuron dysfunction, sensory loss, neurogenic bladder and dementia. A widespread accumulation of polyglucosan bodies (PBs) in the CNS and PNS is the pathological hallmark of the disease. We describe two siblings with the onset of cerebellar and bulbar signs plus urinary frequency in the fourth decade of life. In one of them, brain MRI showed diffuse white matter hyperintensity in T2-weighted images, suggesting a possible diagnosis of leukodystrophy. However, a sural nerve biopsy documented a peripheral neuropathy with conspicuous, typical PBs in myelinated and unmyelinated axons and in endoneurial fibroblasts. These cases indicate that APBD can be clinically heterogeneous and that it should be always considered in the differential diagnosis of leukodystrophies.