Late-onset Leber's hereditary optic neuropathy presenting with longitudinally extensive myelitis harbouring the m.14484T>C mutation: Extending the genotype-phenotype spectrum

Glaucoma: what the neurologist needs to know

Glaucoma is a progressive optic neuropathy resulting from pathological changes at the optic disc due to elevated intraocular pressure. Its diagnosis, treatment and follow-up are almost entirely conducted in ophthalmology clinics, with screening conducted by community optometrists. Despite this, neurologists may encounter glaucoma in both its acute presentation (as angle closure, presenting as acute headache) and its chronic forms (often as optic neuropathy of unknown cause). An awareness of the underlying pathological process, and the key distinguishing signs and symptoms, will allow neurologists to identify the glaucomatous process rapidly. Timely referral is essential as glaucoma invariably results in progressive visual loss without treatment. This review therefore condenses the wide field of glaucoma into a practical summary, aimed at practitioners with limited clinical experience of this ophthalmic condition.

Co-occurrence of glial fibrillary acidic protein astrocytopathy in a patient with Leber's hereditary optic neuropathy due to DNAJC30 mutations

Leber's hereditary optic neuropathy (LHON) is a mitochondrial disease characterized by visual loss, and rarely associated with extraocular manifestations including multiple sclerosis-like lesions. The association of LHON and neuromyelitis optica spectrum disorders has rarely been reported. Here is reported a case of glial fibrillary acidic protein astrocytopathy presenting with area postrema syndrome in a patient with previously diagnosed recessive LHON due to mutations in the nuclear gene DNAJC30. This case emphasizes the necessity of extensive investigations for other treatable conditions in patients with LHON and otherwise unexplained extraocular involvement and the possibility that also visual symptoms can respond to immune therapy.

A Comprehensive Review of Leber Hereditary Optic Neuropathy and Its Association with Multiple Sclerosis-Like Phenotypes Known as Harding's Disease

Leber Hereditary Optic Neuropathy (LHON) stands as a distinctive maternally inherited mitochondrial disorder marked by painless, subacute central vision loss, primarily affecting young males. This review covers the possible relationship between LHON and multiple sclerosis (MS), covering genetic mutations, clinical presentations, imaging findings, and treatment options. LHON is associated with mutations in mitochondrial DNA (mtDNA), notably m.11778G>A, m.3460G>A, and m.14484T>C, affecting complex I subunits. Beyond ocular manifestations, LHON can go beyond the eye into a multi-systemic disorder, showcasing extraocular abnormalities. Clinical presentations, varying in gender prevalence and outcomes, underscore the nature of mitochondrial optic neuropathies. Hypotheses exploring the connection between LHON and MS encompass mitochondrial DNA mutations triggering neurological diseases, immunologically mediated responses inducing demyelination, and the possibility of coincidental diseases. The research on mtDNA mutations among MS patients sheds light on potential associations with specific clinical subgroups, offering a unique perspective into the broader landscape of MS. Imaging findings, ranging from white matter alterations to cerebrospinal fluid biomarkers, further emphasize shared pathological processes between LHON-MS and classical MS. This comprehensive review contributes to the understanding of the complex relationship between LHON and MS.

Magnetic resonance imaging negative myelopathy in Leber's hereditary optic neuropathy: a case report

BACKGROUND

Leber's hereditary optic neuropathy (LHON) is a common form of mitochondrial disease. The typical clinical presentation of LHON is subacute, painless loss of vision resulting from bilateral optic nerve atrophy. Moreover, extra-ocular manifestations such as cardiac conduction abnormalities and neurological manifestations such as multiple sclerosis (MS) like disease or parkinsonism are encountered in some patients. Abnormal findings in spinal cord MR imaging or in the cerebrospinal fluid (CSF) have been observed in previous cases of LHON-associated myelopathy.

CASE PRESENTATION

We report a male patient with LHON who developed symptoms of myelopathy including gait unsteadiness, enhanced deep tendon reflexes and sensory loss of the lower extremities. Imaging of the brain and spinal cord, CSF analysis, as well as neurography and electromyography did not disclose any abnormalities. The somatosensory evoked potential (SEP) findings were suggestive of dorsal column dysfunction.

CONCLUSIONS

The patient case demonstrates that myelopathy associated with LHON can present without abnormal findings in central nervous system MR imaging or in the CSF, and without evidence suggestive of multiple sclerosis or MS-like disease. The dorsal column seems to be particularly vulnerable to myelopathy changes in LHON. Evoked potential investigations may assist in confirming the diagnosis, when clinical features are in line with myelopathy but findings in CSF analysis and central nervous system imaging are normal.

Neuromyelitis Optica Spectrum Disorders

PURPOSE OF REVIEW

This article reviews the cardinal clinical features, distinct immunopathology, current diagnostic criteria, relapse-related risk factors, emerging biomarkers, and evolving treatment strategies pertaining to neuromyelitis optica spectrum disorders (NMOSD).

RECENT FINDINGS

The discovery of the pathogenic aquaporin-4 (AQP4)-IgG autoantibody and characterization of NMOSD as an autoimmune astrocytopathy have spearheaded the identification of key immunologic therapeutic targets in this disease, including but not limited to the complement system, the interleukin 6 (IL-6) receptor, and B cells. Accordingly, four recent randomized controlled trials have demonstrated the efficacy of three new NMOSD therapies, namely eculizumab, satralizumab, and inebilizumab.

SUMMARY

Currently, NMOSD poses both diagnostic and treatment challenges. It is debated whether individuals who are seropositive for myelin oligodendrocyte glycoprotein (MOG)-IgG belong within the neuromyelitis optica spectrum. This discussion is fueled by disparities in treatment responses between patients who are AQP4-IgG seropositive and seronegative, suggesting different immunopathologic mechanisms may govern these conditions. As our understanding regarding the immune pathophysiology of NMOSD expands, emerging biomarkers, including serum neurofilament light chain and glial fibrillary acidic protein (GFAP), may facilitate earlier relapse detection and inform long-term treatment decisions. Future research focal points should include strategies to optimize relapse management, restorative treatments that augment neurologic recovery, and practical solutions that promote equitable access to approved therapies for all patients with NMOSD.