METHODS: In this retrospective, observational study, the presence and phenomenology of movement disorders were assessed with a standardized clinical questionnaire. Available videos were centrally reviewed by three experts in movement disorders.
RESULTS: Seventy two patients were included. In 41 (57%) the main reason for initial consultation was difficulty walking along with one or several concurrent movement disorders. At the time of anti-IgLON5 diagnosis, 63 (87%) patients had at least one movement disorder with a median of three per patient. The most frequent abnormal movements were gait and balance disturbances (52 patients, 72%), chorea (24, 33%), bradykinesia (20, 28%), dystonia (19, 26%), abnormal body postures or rigidity (18, 25%), and tremor (15, 21%). Other hyperkinetic movements (myoclonus, akathisia, myorhythmia, myokymia, or abdominal dyskinesias) occurred in 26 (36%) patients. The craniofacial region was one of the most frequently affected by multiple concurrent movement disorders (23 patients, 32%) including dystonia (13), myorhythmia (6), chorea (4) or myokymia (4). Considering any body region, the most frequent combination of multiple movement disorders consisted of gait instability or ataxia associated with craniofacial dyskinesias or generalized chorea observed in 31(43%) of patients. In addition to abnormal movements, 87% of patients had sleep alterations, 74% bulbar dysfunction, and 53% cognitive impairment. Fifty-five (76%) patients were treated with immunotherapy, resulting in important and sustained improvement of the movement disorders in only seven (13%) cases.
CONCLUSIONS: Movement disorders are a frequent and leading cause of initial neurological consultation in patients with anti-IgLON5 disease. Although multiple types of abnormal movements can occur, the most prevalent are disorders of gait, generalized chorea, and dystonia and other dyskinesias that frequently affect craniofacial muscles. Overall, anti-IgLON5 disease should be considered in patients with multiple movement disorders, particularly if they occur in association with sleep alterations, bulbar dysfunction, or cognitive impairment.
METHODS: Patients with anti-CNTN1+ autoimmune nodopathy detected in our laboratory from which clinical information was available were included. Clinical features and treatment response were retrospectively collected. Autoantibody, serum neurofilament light chain (sNfL), and serum CNTN1 levels (sCNTN1) were analyzed at baseline and follow up.
RESULTS: A total of 31 patients were included. Patients presented with progressive sensory motor neuropathy (76.7%) with proximal (74.2%) and distal involvement (87.1%), ataxia (71.4%), and severe disability (median INCAT at nadir of 8). A total of 11 patients (35%) showed kidney involvement. Most patients (97%) received intravenous immunoglobulin, but only 1 achieved remission with intravenous immunoglobulin. A total of 22 patients (71%) received corticosteroids, and 3 of them (14%) did not need further treatments. Rituximab was effective in 21 of 22 patients (95.5%), with most of them (72%) receiving a single course. Four patients (12.9%) relapsed after a median follow up of 25 months after effective treatment (12-48 months). Anti-CNTN1 titers correlated with clinical scales at sampling and were negative after treatment in all patients, but 1 (20/21). sNfL levels were significantly higher and sCNTN1 significantly lower in anti-CNTN1+ patients than in healthy controls (sNfL: 135.9 pg/ml vs 7.48 pg/ml, sCNTN1: 25.03 pg/ml vs 22,186 pg/ml, p