Hyperammonemia MRI

Clinically:  young female patient with short history of drowsiness, brought unconscious.

MRI brain shows bilateral fronto parietal, temporo parietal cortical T2 hyperintensity with restricted diffusion. Lab report mentions Patient’s serum ammonia was high.

Imaging diagnosis: 

Hyperammonaemia.

DDs:

Differential diagnosis considered were Posterior reversible encephalopathy, CJD (Creutzfeldt-Jakob disease). Possibility of posterior reversible encephalopathy, PRES was ruled out as blood pressure was normal and there was no intra or postpartum history of seizures, eclampsia.

Absence of dementia, very short clinical history and absence of cerebral cortical atrophy on MRI was against CJD.