Neuropathologic Characterisation of Mitochondrial Membrane Protein–Associated Neurodegeneration (MPAN) With Coexisting α‐Synuclein and Tau Pathology in a Young Adult

Mitochondrial membrane protein associated neurodegeneration (MPAN) is a rare and genetically defined subtype of neurodegeneration with brain iron accumulation (NBIA) caused by pathogenic variants in C19orf12. We report an autopsy case in a young adult with a homozygous C19orf12 missense variant. Neuropathological examination demonstrated iron deposition within the globus pallidus, widespread neuroaxonal spheroids, and extensive α-synuclein pathology of the brainstem, limbic and neocortical regions. In addition, we identified focal tau pathology in hippocampus, and entorhinal cortex.