Leber’s hereditary optic neuropathy - Case report

Abstract

Leber's hereditary optic neuropathy is the most common mitochondrial condition and is characterized by bilateral, painless, subacute visual loss that develops during young adult life. LHON is a rare condition and this lack of knowledge can make doctors suspect and treat for other causes of vision loss. Typically, a series of tests are performed to confirm LHON diagnosis or exclude any other conditions. We presented the case of two brothers, HB, of 40 years old and HF, of 38 years old, who presented with a decrease in visual acuity in both eyes. The patients had been diagnosed with optic atrophy of unknown cause a long time ago, but no further investigations were made. They were treated with corticosteroids, antioxidants and vasodilators, but with no significant benefit. A blood test of the mitochondrial DNA, a magnetic resonance imaging and an optic coherence tomography of the optic nerve and macula were part of the following assessment of our patients. The mitochondrial DNA analyses revealed the 3460 G>A mutation on the mtND1 gene in both patients. Based on the medical history, the fundus aspect, the optic coherence tomography and the paraclinical investigations of the diagnosis of Leber's hereditary optic neuropathy were established in both patients. We started the treatment with idebenone and we evaluated the patients after three months. Keywords: Leber's hereditary optic neuropathy, mitochondrial DNA test, optic coherence tomography, idebenone Abbreviations: LHON = Leber's hereditary optic neuropathy, mtDNA = mitochondrial DNA, VA = visual acuity, CF = count fingers, OCT = optical coherence tomography, RNFL = retinal nerve fiber layer, GCL = ganglion cells layer, MS = multiple sclerosis, MRI = magnetic resonance imaging, MTI = magnetization transfer imaging, MTR = magnetization transfer ratio

The Evaluation of Optic Nerves Using 7 Tesla “Silent” Zero Echo Time Imaging in Patients with Leber’s Hereditary Optic Neuropathy with or without Idebenone Treatment

“…Inglese et al showed that optic nerve volume, mean diffusion and Magnetization Transfer Ratio measures were changed in LHON [34]. Iorga et al showed that optic nerve volumes measured on 3D T1-weighted images were lower in two familial cases of LHON [35].…”

Further advances in the diagnosis and treatment of Leber’s Hereditary Optic Neuropathy – a review

“…The efficacy and safety of idebenone was assessed by Klopstock et al in 2011 in the RHODOS study [12,19,[26][27][28]. The experts' consensus of idebenone recommends that the treatment should start in the first year from visual loss onset (in the acute stage), as early as possible, the administration of the idebenone dose of 900 mg/ day being given into three daily doses of 300 mg with meals [12,29]. Treatment should be given for at least 12 months to assess a therapeutic response, then discontinuation of the drug should be considered after 12 months once a plateau recovery is reached, or no improvements are observed [12,29].…”

“…The experts' consensus of idebenone recommends that the treatment should start in the first year from visual loss onset (in the acute stage), as early as possible, the administration of the idebenone dose of 900 mg/ day being given into three daily doses of 300 mg with meals [12,29]. Treatment should be given for at least 12 months to assess a therapeutic response, then discontinuation of the drug should be considered after 12 months once a plateau recovery is reached, or no improvements are observed [12,29]. Two others multicenter studies (LEROS and PAROS) were launched after the idebenone commercial approval, being designed to assess the long-term efficacy and safety of the drug [12].…”

Early identification of LHON carriers may improve outcome

“…We read with interest about two brothers with Leber’s hereditary optic neuropathy (LHON) due to the ND1 variant m.3460G>A by Iorga et al [ 1 ]. We have the following comments and concerns.…”

“…Another inadequacy of the study is that no family screening for the pathogenic variant had been carried out [ 1 ]. Accordingly, we do not know who else in the family carried the mutation.…”