Dados do Trabalho

Título

Anti-IgLON5 subclass IgG1 disease: case report

Introdução

A number of autoantibodies are recently being associated with sleep disorders. In the last 5 years, cases of a novel tauopathy associated with IgLON5 antibodies are being recognized in patients with obstructive sleep apnea, stridor, REM sleep disorders, bulbar symptoms and dysautonomia. Anti-IgLON5 subclass IgG1 and IgG4 are related to the disease, but its phenotype differences are not known yet.

Objetivo

To report a case of Anti-IgLON5 disease with the less common subclass IgG1 antibody.

Métodos

Several clinical evaluations and follow-up of the patient.

Resultados

A 75-year-old man reported insomnia since 40 years old, followed later by snoring, and sleep fragmentation, being diagnosed at age of 68 with moderate obstructive sleep apnea (OSA). He presented severe symptomatic bradycardia, so it was implanted a permanent pacemaker. By 70 years, the patient evolved with progressive dysphagia, dysarthria and nocturnal laryngeal stridor. Otorhinolaryngological evaluation showed vocal cord paralysis. After recurrent pneumonia, he was submitted to tracheostomy that occurred with laryngeal stenosis, treated with serial dilations without improvement and later laryngectomy. He also refers symptoms of restless legs syndrome, REM sleep behavioral disorder (RBD), sleep talking, and nocturnal myoclonus. No cognitive impairment or extrapyramidal symptoms. From the diagnostic suspicion, we investigated and demonstrated HLA-DRB1* and HLA-DQB1* in homozygosis and CSF analysis with anti-IgLON5 subclass IgG1. Head CT without significant abnormalities, polysomnography with low sleep efficiency, poor structured NREM sleep, severe OSA, PLMS, and REM sleep without atonia. CPAP was titrated and initiated to OSA control and clonazepam 0.5mg for RBD with good response. Submitted to 3 immunoglobulin cycles without clinical improvement. Evolved with ophthalmoplegia. We prescribed rituximab and the patient responded with good tolerance and had mild improvement of visual symptoms.

Conclusões

Anti-IgLON5 disease is a rare sleep condition, which may develop sleep disordered breath, bulbar symptoms, dysautonomia and gaze palsy. It is not known yet whether subclass IgG1 and IgG4 antibodies lead to clinical different diseases.

Palavras-chave

IgLON5, autoimmunity, tauopathy