Mitochondrial membrane protein-associated neurodegeneration
Mitochondrial membrane protein-associated neurodegeneration (MPAN) is a rare subtype of neurodegeneration with brain iron accumulation disease (NBIA).
MPAN usually presents before 10 years old. At least one case of late-onset (35 years old) has been reported 3. Less than a hundred of cases have been reported so far and it accounts for approximately 5% of cases of NBIA 1.
Clinical features consist of early onset of gradually worsening varying neurological symptoms that overlap with those of PKAN. Neurological manifestations described include: parkinsonism, muscle atrophy, dysphagia, dysarthria, incontinence, ocular-motor disturbance, incontinence, cerebellar signs, psychiatric disorders, cognitive disorders, etc 1.
MPAN is an autosomal-recessive genetic disorder caused by a mutation of the C19orf12 gene associated with inappropriate brain iron deposition.
The most important findings are seen on T2-WI.
- hyperintense linear signal in the medial medullary laminae (in-between the segments of the globus pallidus) 2
- hypointense signal in the globus pallidus (nonspecific finding suggestive of brain iron deposition) and, albeit less frequent, in the substantia nigra 2
- nonspecific periventricular hyperintensities 2
Cerebellar atrophy has also been described in some cases.
- 1. Deutschländer A, Konno T, Ross OA. Mitochondrial membrane protein-associated neurodegeneration. Parkinsonism & related disorders. 39: 1-3. doi:10.1016/j.parkreldis.2017.03.014 - Pubmed
- 2. Skowronska M, Kmiec T, Jurkiewicz E, Malczyk K, Kurkowska-Jastrzębska I, Czlonkowska A. Evolution and novel radiological changes of neurodegeneration associated with mutations in C19orf12. Parkinsonism & related disorders. 39: 71-76. doi:10.1016/j.parkreldis.2017.03.013 - Pubmed
- 3. Gore E, Appleby BS, Cohen ML, DeBrosse SD, Leverenz JB, Miller BL, Siedlak SL, Zhu X, Lerner AJ. Clinical and imaging characteristics of late onset mitochondrial membrane protein-associated neurodegeneration (MPAN). Neurocase. 22 (5): 476-483. doi:10.1080/13554794.2016.1247458 - Pubmed