A recent retrospective study provides an overview of the clinical and demographic characteristics of neuromyelitis optica spectrum disorder patients in Slovakia.
Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune, inflammatory disease of the central nervous system, predominantly affecting the optic nerves and the spinal cord. It has two distinct phenotypes based on the presence of antibodies targeting aquaporin-4 (AQP4-IgG).
A study in Neurological Sciences has presented demographic and clinical data of NMOSD patients in Slovakia and evaluated the differences between AQP4-IgG-seropositive and AQP4-IgG-seronegative patients.
The study was a longitudinal multi-center retrospective analysis of a cohort of 63 Slovakian NMOSD patients.
Demographic Characteristics of NMOSD Patients
Of the 63 patients, 61 (93.8%) were Caucasian and two (3.2%) were Roma. The female-to-male ratio was 6:1, with 54 (85.7%) female patients. The median age at diagnosis was 37 years, and the median disease duration was 6 years.
Optic Neuritis and Transverse Myelitis With a Relapsing Course
The most frequent initial clinical manifestations were optic neuritis (47.6% of patients) and transverse myelitis (39.7%). The percentage of patients experiencing at least one attack of optic neuritis or transverse myelitis during the disease course was 82.5% and 77.8%, respectively. Most patients (81%) had the relapsing form of the disease, with an annual attack rate of one. The median Expanded Disability Status Scale score deteriorated from the initial 3.0 to 4.0 by the last follow-up. One patient died during follow-up. Comorbidities were reported in 38.1% of patients, with another 38.1% suffering from a concomitant autoimmune disease.
Laboratory and Imaging Findings in NMOSD Patients
Oligoclonal IgG bands were detected in the cerebrospinal fluid of 15 out of 53 patients who underwent a cerebrospinal fluid exam. Brain magnetic resonance imaging (MRI) during acute attacks demonstrated T2 hyperintense lesions in optic nerves/optic chiasm (34.1%), brainstem (17.1%), and diencephalon (4.9%), and atypical cerebral lesions in 46.3% of patients, whereas normal findings were observed in 4.9% of patients. Spinal cord MRI demonstrated longitudinal extensive transverse myelitis (LETM) in 63.4%, non-LETM lesions in 9.8%, and normal findings in 26.8% of patients.
High Prevalence of Autoimmune Thyroiditis Observed in AQP4-IgG-Positive Patients
Of the 63 patients, 43 (68.3%) were AQP4-IgG-positive, and 20 (31.7%) were AQP4-IgG-negative. Longer disease duration and higher age at the last follow-up were observed in AQP4-IgG-positive patients (p = 0.04) compared to seronegative patients. Male AQP4-IgG-negative patients were younger than male seropositive patients (p = 0.02). Autoimmune comorbidities alone were more frequent in male AQP4-IgG-seronegative patients than in male seropositive patients (p = 0.05).
Most importantly, a higher prevalence of autoimmune thyroiditis was seen among AQP4-IgG-positive patients (25.6%) compared to AQP4-IgG-negative patients (0%) (p = 0.01). There were no differences between the two AQP4-IgG subgroups in the frequency of comorbidities in general or in other disease characteristics.
Szilasiová, J., Gazda, J., Mikula, P., Cvengrošová, A., Fedičová, M., Hančinová, V., Kantorová, E., Karlík, M., & Kováčová, S. (2023). Clinical and demographic characteristics of patients with NMOSD: a longitudinal retrospective analysis of a Slovak cohort of 63 patients. Neurological Sciences. https://doi.org/10.1007/s10072-023-07050-x