Further investigations
| Investigation | Result |
|---|---|
| B12 and folate | Normal |
| Leucocyte and plasma enzymes | |
| Serum antinuclear antibody | |
| Serum protein electrophoresis | |
| Urine porphyrin screen | |
| Urine organic acids | |
| Cerebrospinal fluid | No oligoclonal bands |
| Evoked potentials | Bilateral delay of tibial sensory evoked potentials, particularly on the left. Visual evoked potentials were normal. Right brainstem auditory evoked potentials were mildly delayed |
| Repeat MR scan of brain | Axial MR scan of brain (see figure 1) showed signal change in the brainstem and cerebellar white matter with bilateral symmetrical high signal in both thalami. T2-weighted low signal in the globi pallidi and cerebral peduncle, consistent with mineralisation. Also, symmetrical signal change in the lentiform nuclei, pons, cerebellar hemispheres, dentate nuclei with some cystic component and infratentorial atrophy. Appearance favours Wilson's disease or Leigh's syndrome |
| Muscle biopsy | Non-specific fat storage abnormality |
| Amino acid levels | Raised tyrosine (may indicate liver involvement) |