CSF1R and Hereditary diffuse leukoencephalopathy with axonal spheroids and pigmented glia: Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP), a leukodystrophy characterized by dementia with neuropsychiatric deficits, is considered a single clinicopathologic entity of familial pigmented orthochromatic leukodystrophy (POLD) and hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS), both of which are caused by autosomal dominant mutations in the colony-stimulating factor 1 receptor (CSF1R) gene [1–4].