Leber's Hereditary Optic Neuropathy Associated with the m.10197G>A Mutation

Abstract

Letter to the EditorLeber hereditary optic neuropathy (LHON) is an optic neuropathy caused by homoplasmic or heteroplasmic mtDNA mutations, which predominantly cause damage to the retinal ganglion cells (RGCs). The mtND3*10197A (m.10197G>A) mutation has been identified as the novel causative gene in Chinese patients with LHON and dystonia [1]. The m.10197G>A mutation also has been detected in patients with bilateral basal ganglia lesions and Leigh syndrome [2][3][4]. This mutation substitutes a threonine for an alanine at codon 47 of MTND3.A 23-year-old Taiwanese man with a history of blunt ocular injury was referred to our clinic after sequential subacute onset of bilateral painless vision loss. The patient experienced blunt trauma to the left eye and was diagnosed with traumatic optic neuropathy four months prior to the onset of vision loss. At that time, his visual field examination showed cecocentral scotoma in the left eye and a normal visual field in the right eye. The Humphrey visual field (HVF) 30-2 showed a mean deviation (MD) of -10.70 dB in the left eye and -3.98 dB in the right eye ( Figure 1A). He had no other neurological deficits at the time of injury. However, he noted painless visual deterioration of the right eye 2 months later. His visual acuity was 20/150 in the right eye, and 20/100 in the left eye. The patient failed to recognize any of the Ishihara color plates. The anterior segment of the eyes and extraocular movements were all unremarkable. The optic nerve heads were largely cupped with bilateral pallor over the temporal part of neural rim, and there was no prominent peripapillary telangiectasia in either eye. His HVF showed a progressive cecocentral scotoma in both eyes, which was worse in the non-traumatic eye. The MD had progressed to -14.83 dB in the left eye and -20.83 dB in the right eye ( Figure 1B). His OCT showed a severe loss of the ganglion cell complex (GCC) and thinning of the left peripapillary retinal nerve fiber layer (RNFL) (Figure 2A). Magnetic resonance imaging (MRI) of the brain/ orbits showed a normal optic nerve appearance bilaterally without enhancement and no periventricular white matter lesions. A review of the patient's medical history and family history was unremarkable. The patient had smoked for the past 10 years and denied current or past alcohol abuse. The patient underwent blood testing, which included biochemistry tests, a complete blood count (CBC), and tests for serum electrolytes, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), antinuclear antibodies (ANA), anti-double-stranded DNA antibodies (anti-dsDNA-Ab), protoplasmic/cytoplasmic antineutrophil cytoplasmic antibodies (p/c ANCA), angiotensin converting enzyme (ACE), antiphospholipid Ab, rheumatoid factor (RF), vitamin B12, and aquaporin-4 Ab. All tests were within the normal range or negative.

Hormone replacement therapy in Leber's hereditary optic neuropathy: Accelerated visual recovery in vivo

“…While causality cannot be definitively proven, the patient's presentation in association with estrogen deficiency and the absence of alternative triggers is highly suggestive of estrogen's protective role in LHON. Also, LHON 10197, characterized by an ND3 subunit defect in mitochondrial complex I, has been solely identified in patients with Leigh syndrome, Leigh-like syndrome, and LHON and dystonia [7], [8]. Our case provides the first reporting of this mutation with isolated LHON, as the patient had no accompanying neurological deficits.…”

Genotype and phenotype association in Leber’s hereditary optic neuropathy

“…Ap ra ðy ti tik at ski ri PLON ir LDYT atve jai. m.10197G>A mu ta ci ja ga li su kel ti ti pi ná PLON feno ti pà tiek mo te rims, tiek vy rams, ga li mas li gos pa si reiðki mas ir vy res nia me am þiu je [43,44]. Taip pat ga li mas LDYT fe no ti pas, ku rá su da ro PLON ir pro gre suo jan èios ge ne ra li zuo tos dis to ni jos de ri nys [45].…”