title: Pupillary dysfunction in an atypical case of mitochondrial myopathy with tubular aggregates.
abstract: A 62-year-old man presented with diplopia, ocular ductional deficits, and sluggish pupils. Pupillometry demonstrated large hyporeactive pupils with no evidence of damage to the sympathetic or parasympathetic innervation, indicating a myopathy of the iris musculature. A single large deletion in mitochondrial DNA and characteristic histochemical features on muscle biopsy suggested a mitochondrial cytopathy. However, ultrastructural examination of skeletal muscle fibers showed tubular aggregates (TAs), a finding not reported in mitochondrial cytopathy. The combination of pupillary abnormalities and TAs suggests that mitochondrial dysfunction may not explain the full extent of abnormalities in this case.
authors.affiliation: Department of Neuro-Ophthalmology, National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom. nadeem.ali@nhs.net
authors.forename: Nadeem
authors.initials: N
authors.lastname: Ali
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Woodward
authors.forename: Mary
authors.initials: M
authors.lastname: Sweeney
authors.forename: Rahul
authors.initials: R
authors.lastname: Phadke
authors.forename: Janice L
authors.initials: JL
authors.lastname: Holton
authors.forename: James
authors.initials: J
authors.lastname: Acheson
authors.forename: Gordon T
authors.initials: GT
authors.lastname: Plant
authors.forename: Fion D
authors.initials: FD
authors.lastname: Bremner
mesh_terms: D001706:Biopsy; D002908:Chronic Disease; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000032:analysis / Q000235:genetics; D017353:Gene Deletion; D006801:Humans; D002479:Inclusion Bodies / Q000473:pathology; D007498:Iris / Q000473:pathology / Q000503:physiopathology; D007499:Iris Diseases / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D046529:Microscopy, Electron, Transmission; D008870:Microtubules / Q000473:pathology; D008875:Middle Aged; D008928:Mitochondria / Q000235:genetics / Q000473:pathology; D017240:Mitochondrial Myopathies / Q000150:complications* / Q000473:pathology / Q000503:physiopathology*; D018485:Muscle Fibers, Skeletal / Q000473:pathology / Q000648:ultrastructure; D018482:Muscle, Skeletal / Q000473:pathology / Q000503:physiopathology; D009130:Muscle, Smooth / Q000473:pathology / Q000503:physiopathology; D009154:Mutation / Q000235:genetics; D011681:Pupil Disorders / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology*
chemical_list: D004272:DNA, Mitochondrial