The aquaporin4-IgG status and how it affects the clinical features and treatment response in NMOSD patients in Egypt

Sex ratio and age of onset in AQP4 antibody-associated NMOSD: a review and meta-analysis

BACKGROUND

Aquaporin-4 (AQP4) antibody-associated neuromyelitis optica spectrum disorder (NMOSD) is an antibody-mediated inflammatory disease of the central nervous system. We have undertaken a systematic review and meta-analysis to ascertain the sex ratio and mean age of onset for AQP4 antibody associated NMOSD. We have also explored factors that impact on these demographic data.

METHODS

A systematic search of databases was conducted according to the PRISMA guidelines. Articles reporting sex distribution and age of onset for AQP4 antibody-associated NMSOD were reviewed. An initially inclusive approach involving exploration with regression meta-analysis was followed by an analysis of just AQP4 antibody positive cases.

RESULTS

A total of 528 articles were screened to yield 89 articles covering 19,415 individuals from 88 population samples. The female:male sex ratio was significantly influenced by the proportion of AQP4 antibody positive cases in the samples studied (p < 0.001). For AQP4 antibody-positive cases the overall estimate of the sex ratio was 8.89 (95% CI 7.78-10.15). For paediatric populations the estimate was 5.68 (95% CI 4.01-8.03) and for late-onset cases, it was 5.48 (95% CI 4.10-7.33). The mean age of onset was significantly associated with the mean life expectancy of the population sampled (p < 0.001). The mean age of onset for AQP4 antibody-positive cases in long-lived populations was 41.7 years versus 33.3 years in the remainder.

CONCLUSIONS

The female:male sex ratio and the mean age of onset of AQP4 antibody-associated NMOSD are significantly higher than MS. The sex ratio increases with the proportion of cases that are positive for AQP4 antibodies and the mean age of onset increases with population life expectancy.

Area postrema syndrome in neuromyelitis optica spectrum disorder: diagnostic challenges and descriptive patterns

Background

Although area postrema syndrome (APS) is one of the core clinical features of neuromyelitis optic spectrum disorder (NMOSD), it is frequently misdiagnosed as gastrointestinal or systemic disorders. In this study, we describe the diagnostic challenges in NMOSD patients with APS and their characteristic clinical and radiological features. All patients who attended our university hospitals during the period from March 2019 to August 2020 with a diagnosis of NMOSD according to the latest diagnostic criteria were admitted and evaluated clinically, radiologically with gadolinium-enhanced brain and spinal MRI, measures of serum Anti-Aquaporin 4 (Anti-AQP4) and clinical status using the Expanded Disability Status Scale (EDSS) scores. APS was diagnosed if there was a history of intractable nausea, vomiting, or hiccups (INVH) that had lasted longer than 1 week with the exclusion of other etiologies, or less than 48 h if associated with a lesion in the dorsal medulla on MRI scan.

Results

Twenty out of 90 (22.2%) identified patients with a diagnosis of NMOSD had a history of unexplained intractable nausea, vomiting or hiccoughs lasting an average of 20 days. Seventeen patients were anti-Aquaporin 4 seropositive. Seven patients (35%) presented initially with isolated clinical features of APS and were diagnosed only after subsequent relapse. Patients with APS preceding other core clinical presentations (13 cases, 65%) were diagnosed after development of motor manifestations. All patients developed acute myelitis during the course of illness. Brain and spinal MRI scans showed that 13 had a linear lesion in the dorsal tegmentum of the medulla oblongata adjacent to the fourth ventricle. Otherwise, longitudinally extensive transverse myelitis was found in 80%, while 35% showed extension of the cord lesion to the AP.

Conclusions

APS as a core clinical characteristic of NMOSD is not a rare presentation as was previously thought and can occur in both AQP4-seropositive and seronegative NMOSD.

Comparisons of clinical phenotype, radiological and laboratory features, and therapy of neuromyelitis optica spectrum disorder by regions: update and challenges

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) associated with autoantibody (ab) to aquaporin-4 (AQP4). There is obvious variation between regions and countries in the epidemiology, clinical features and management in NMOSD. Based on published population-based observation and cohort studies, the different clinical pattern of NMOSD has been seen in several geographical regions and some of these patients with NMOSD-like features do not fully meet the current diagnostic criteria, which is needed to consider the value of recently revised diagnostic criteria. At present, all treatments applied in NMOSD have made great progress, however, these treatments failed in AQP4 ab negative and refractory patients. Therefore, it is necessary to turn into an innovative idea and to open a new era of NMOSD treatment to develop novel and diverse targets and effective therapeutic drugs in NMOSD and to conduct the trails in large clinical samples and case-control studies to confirm their therapeutic effects on NMOSD in the future, which still remain a challenge.