Unusual Head Movements in Anti‐IgLON5 Disease

Abstract

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Head Drop and Trunk Flexion as an Early Manifestation of Anti‐IgLON5 Disease

“…In a single previous report, an unusual forward-flexion movement of the neck as a presenting feature of anti-IgLON5 was described and these movements, being sustained, were classified as dystonia. 5 In contrast, our case showed a mixture of abrupt head drops and less abrupt, less sustained, neck and trunk flexion. A single previous report described the 18F-FDG-PET findings in this disease, which were hypometabolism in the primary sensorimotor cortices, basal ganglia, and cerebrum.…”

“…We have seen head drops in a few cases of genetically confirmed Huntington's disease (unpublished observation). In a single previous report, an unusual forward‐flexion movement of the neck as a presenting feature of anti‐IgLON5 was described and these movements, being sustained, were classified as dystonia 5 . In contrast, our case showed a mixture of abrupt head drops and less abrupt, less sustained, neck and trunk flexion.…”

Unusual Head Drops, Neck and Truncal Dystonia and Sleep Orthopnea with a Favorable Treatment Response in IgLon5 Antibody Disease

“…IgLON5‐Ab disease has been proposed as a common cause of autoimmune chorea making it a close differential diagnosis of Huntington's disease 4 . Interestingly, intermittent “head drops” in older adults especially with prominent sleep disturbances, 5–7 truncal dystonia (pisa syndrome), 5 multiple system atrophy‐like (head drop, ED) presentation without other autonomic dysfunction, 4 sleep orthopnea, anterior horn cell involvement, orthostatic myoclonus 8 and significant weight loss 9 have all been reported earlier in IgLON5Ab disease and many of these features were seen in our patient. As exemplified by our case, recognition of new and unusual phenotypes of anti‐Iglon5 Ab disease are important, as missing the time window of treatability may have grave consequences for patients with this novel and potentially treatable disorder.…”

Anti-IgLON5 Disease – The Current State of Knowledge and Further Perspectives

“…Anti-IgLON5 disease, a progressive disorder which combines autoimmunization with neurodegeneration, may have a very heterogenous manifestation. The core of the clinical presentation consists of sleep disorder, bulbar symptoms and gait abnormality followed by cognitive dysfunction ( 12 , 30 , 31 ). Other common symptoms include oculomotor abnormalities such as vertical/horizontal gaze palsy, nystagmus or ptosis ( 28 , 32 ).…”