The Heidenhain variant of Creutzfeldt-Jakob disease

A 65-year-old man presented to the accident and emergency department with a 2-week history of progressive confusion with visual hallucinations. This began with symptoms of photosensitivity and the distorted appearance of objects and progressed to an unsteady gait and problems with spatial awareness. By the end of the second week he displayed evidence of cognitive impairment and was admitted to hospital. On the day of his admission, he required the assistance of one person to mobilize and could converse, although he was not orientated to time or place. He began to display signs of frontal disinhibition becoming uncharacteristically aggressive and using foul language. On initial examination, he had no evidence of facial asymmetry, visual fields were intact, and his pupils were equal and reactive to light. Mild dysdiadochokinesia was noted, worse on the left, with mild dysmetria bilaterally. He had normal power and tone in all four limbs. Blood tests including an autoimmune screen were unremarkable (haemoglobin 148 g/ litre, white cell count 7.30x109/litre, platelets 259x109/litre, serum potassium 4.3 mmol/litre, serum urea 6.1 mmol/litre, serum creatinine 89 mmol/litre, serum bilirubin 9 umol/litre, serum alkaline phosphatase 56 U/litre, serum alanine transaminase 33 U/litre, plasma glucose 7.6 mmol/litre, serum vitamin B-12 193 ng/litre, serum folate 6.5 ug/litre, serum hepatitis Bs antigen negative, serum hepatitis C IgG antibody 1&2 negative, serum syphilis IgG/IgM negative, serum intrinsic factor antibody negative, serum cardiolipin screen negative, serum antineutrophil cytoplasm antibody negative, serum ANA immunoassay screen negative). A lumbar puncture was performed and the samples were sent to the National CreutzfeldtJakob disease (CJD) Research and Surveillance Unit in Edinburgh. The findings were white cell count < 5/mm(3), red cell count < 100/mm(3), total protein 1.02 g/litre, glucose non-consumed, S100-b 0.54 ng/ml (reference range < 0.41 ng/ml), and real time quaking induced conversion and protein 14-3-3 positive. An electroencephalogram demonstrated characteristic features of Creutzfeldt-Jakob disease with diffuse slowing and periodic sharp wave complexes (Figure 1). Magnetic resonance imaging of his brain showed increased signal restricted diffusion within the caudate nuclei bilaterally (Figures 2a and b) with further restricted diffusion of the cortex in the frontal, parietal and occipital lobes on the right (Figures 3a and b). Diffusion-weighted magnetic resonance imaging has the highest diagnostic accuracy (similar to 97%) (sborn et al, 2015). In this case, the observed asymmetrical involvement predominantly of the occipital lobe on the right side on axial magnetic resonance imaging highlights the increased possibility of the Heidenhain variant of Creutzfeldt-Jakob disease. During the following 10 days, his tone increased in all four limbs with hyperreflexia and associated dystonic posturing of both upper limbs. He had bilateral grasp reflexes and there were frequent myoclonic jerks of his upper limbs. He had a fixed gaze with a restrictive horizontal gaze. He was transferred to a hospice where his myoclonus and agitation were wellcontrolled by a phenobarbital infusion. He died 2 days after admission to the hospice.