Anti-IgLON5 disease with distinctive brain MRI findings responding to immunotherapy: A case report

RATIONALE

Anti-IgLON5 disease was first described as a progressive antibody-associated encephalopathy, with multiple non-specific clinical symptoms including sleep dysfunction, bulbar symptoms, progressive supranuclear palsy-like syndrome, cognitive impairment, and a variety of movement disorders. This newly discovered disease presents with unremarkable or unspecific brain magnetic resonance imagings (MRI), and have poor responsiveness to immunotherapy.

PATIENT CONCERNS

In this case, a 37-year-old man presented with 4-day history of gait instability, dysarthria, and oculomotor abnormalities. The initial neurologic examination revealed mild unsteady gait, subtle dysarthria, and left abducent paralysis.

DIAGNOSIS

The patient was diagnosed with anti-IgLON5 disease, based on clinical features and positive anti-IgLON5 antibodies in serum.

INTERVENTIONS

Initially, the patient was treated with high dosages of methylprednisolone and immunoglobulins.Outcomes: The symptoms of patient rapidly improved after high-dose intravenous methylprednisolone and immunoglobulins.

CONCLUSIONS

In this paper, we report a new case of anti-IgLON5 disease with major symptoms of gait instability, dysarthria, and oculomotor abnormalities, with distinctive brain MRI findings, and responsive to immunotherapy.

Unilateral Oculomotor Nerve Palsy Following Campylobacter Infection: A Mild Form of Miller Fisher Syndrome without Ataxia

Unilateral oculomotor nerve palsy can result from various neurological disorders. We herein report the case of a 68-year-old man with complete unilateral oculomotor nerve palsy following campylobacter infection. Based on the antecedent infection and the patient's decreased tendon reflexes, incomplete Miller Fisher syndrome (MFS) without ataxia was suspected. His serum tested positive for anti-GQ1b antibodies. He recovered over a period of 87 days without immunotherapy. We conclude that incomplete MFS following campylobacter infection can cause unilateral oculomotor nerve palsy without ataxia. Mild MFS should be considered in patients presenting with unilateral isolated ophthalmoplegia and decreased tendon reflexes.

Adie's pupils in paraneoplastic ganglionopathy with ANNA-1

Autonomic disturbances are common in patients with paraneoplastic syndromes associated with type-1 antineuronal nuclear autoantibodies (ANNA-1), although pupillary disturbances are infrequent. The authors describe a patient with ANNA-1 associated paraneoplastic sensory neuronopathy and bilateral Adie's pupils.

Potential Role of Anti-GAD Antibodies in Abnormal Eye Movements

Glutamic acid decarboxylase (GAD) catalyzes the conversion of glutamic acid to gamma-aminobutyric acid (GABA). Autoantibodies directed against GAD (antiGAD-Ab) have been described in patients with insulin-dependent diabetes mellitus, stiff-man syndrome, and in a few patients with progressive cerebellar ataxia. The presence of these autoantibodies suggests an autoimmune pathophysiological mechanism for the neurological manifestations in these disorders. However, the exact role of antiGAD-Ab and GABAergic neurotransmission in the pathogenesis of the neurological manifestations, particularly in progressive cerebellar ataxia, is not fully understood. The cases of two patients with subacute cerebellar ataxia associated with antiGAD-Ab presenting with abnormal eye movements are reported. One patient presented a periodic alternating nystagmus (PAN), whereas the other presented a downbeat nystagmus (DBN) and slow vertical saccades. The potential role of antiGAD-Ab and the resultant GABAergic neurotransmission deficit in oculomotor manifestations is discussed.

Neuro-ophthalmology and paraneoplastic syndromes

PURPOSE OF REVIEW

To describe the neuro-ophthalmological manifestations of paraneoplastic syndromes and their immunological associations.

RECENT FINDINGS

Neuro-ophthalmological signs and symptoms are usually present in paraneoplastic syndromes of the central nervous system. Unlike opsoclonus, less characteristic eye movement abnormalities are difficult to recognize as presenting symptoms of paraneoplastic syndromes. In this setting, the detection of several antibodies, including anti-Hu, Yo, Ma2, Ri, Tr, CV2/CRMP5 or voltage-gated calcium channel antibodies may help to establish that the neuro-ophthalmological disorder is paraneoplastic. Among the recently characterized antibodies, those against the Ma proteins often associate with brainstem encephalitis and vertical gaze paralysis. A small subset of patients with opsoclonus and ataxia harbor anti-Ri antibodies. In other patients, there is preliminary evidence that the autoantigens of opsoclonus reside in the postsynaptic density, but no dominant antibody marker has been identified. Uveitis and optic neuritis are rare accompaniments of paraneoplastic encephalomyelitis; some of these patients harbor anti-CV2/CRMP5 in association with other antibodies. Studies on paraneoplastic retinopathy indicate that immunity to retinal proteins other than recoverin can result in a similar syndrome to that associated with recoverin antibodies, and that melanoma-associated retinopathy may associate with several retinal antibodies.

SUMMARY

There is increasing recognition of an extensive variety of neuro-ophthalmological abnormalities as manifestations of paraneoplastic syndromes and of several antineuronal antibodies as clinical markers of these disorders. Basic immunological studies support the pathogenic role of some of these antibodies, and are elucidating the pathogenic mechanisms that underlie these and other antibody-associated paraneoplastic syndromes.

Partial oculomotor nerve palsy associated with elevated anti-galactocerebroside and anti-GM1 antibodies

An 11-year-old girl had a painless oculomotor nerve palsy confined to the inferior division. Anti-galactocerebroside and anti-GM1 antibodies were elevated during the acute phase and decreased to normal limits with clinical improvement, suggesting a possible autoimmune basis for this mononeuropathy.