Histopathology of different brain regions of HAD patient A (a-c) and patient B (d-f). Extensive astrocytosis (a and d) was seen in most brain regions in case of both HAD patients (13/26 in the patient A and 11/20 in the patient B). Focal neurophagia was observed in the left occipital lobe of patient A (b) and left hippocampus of patient B (e) individually, although it was only found in very limited regions (4/26 in the patient A and 1/20 in the patient B). Severe microglial nodules (c) were been observed in 12/26 regions of patient A, but the absence in the patient B. Encephalopathy (f) was identified in 5/26 regions in the patient A and 3/20 in the patient B, respectively. Arrows in the figure signify each of the pathologic features outlined above. a: right basal ganglia, b: left occipital lobe, c: left basal ganglia, d: left basal ganglia, e: left hippocampus, f: mid brain.