MOG-IgG testing strategies in accordance with the 2023 MOGAD criteria: a clinical-laboratory assessment

BACKGROUND

Live cell-based assay (LCBA) is the gold standard for MOG-IgG detection, and fixed CBA (FCBA) is a widely used commercial alternative. Recent criteria attributed a diagnostic value to MOG-IgG titration with both LCBA and FCBA, with low-titre samples requiring additional supporting features for MOGAD diagnosis. However, FCBA titration is not validated. We aimed to assess the impact of the criteria-based MOG-IgG testing in MOGAD diagnosis.

METHODS

Thirty-eight serum samples of LCBA MOG-IgG1-positive MOGAD patients were titred on MOG-IgG LCBA and FCBA, and the presence of supporting features for MOGAD assessed. MOGAD criteria were evaluated in four testing scenarios: (a) FCBA without titration; (b) FCBA with titration; c) LCBA without titration; (d) LCBA with titration.

RESULTS

FCBA without titration failed to reach MOGAD diagnosis in 11/38 patients (28.9%, negative results in 5, lack of supporting features in 6). Patients with unconfirmed diagnosis had optic neuritis (ON, n = 8), or transverse myelitis (TM, n = 3). FCBA with titration allowed MOGAD diagnosis in 4 additional patients. Correlation between LCBA and FCBA titres was moderate (Spearman's rho 0.6, p < 0.001).

CONCLUSIONS

FCBA yields high rate of misdiagnosis mainly due a lower analytical sensitivity. FCBA titration provides a moderate diagnostic advantage in FCBA positive patients.

Cerebrospinal fluid eosinophils in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Eosinophils in cerebrospinal fluid (CSF) are an uncommon finding most often associated with parasitic infections, but have also been described in some neuroinflammatory disorders. Eosinophilic infiltration is not thought to be a typical feature of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). We aim to describe the rate of CSF eosinophil positivity in a cohort of pediatric MOGAD patients.

METHODS

Single-center retrospective chart review of pediatric MOGAD patients. Clinical and laboratory data was collected from the electronic medical record and analyzed.

RESULTS

Of 46 pediatric patients with positive serum myelin oligodendrocyte glycoprotein antibody (MOG-IgG) identified, 38 patients fulfilling internationally proposed MOGAD diagnostic criteria were included for analysis. 6 patients with MOGAD were excluded as no CSF data was available, and 2 patients with positive MOG-IgG but diagnosis more consistent with MS were excluded. Median age was 7.3 years, and 19/38 (50 %) were female. Acute disseminated encephalomyelitis (ADEM) was the most common presenting phenotype (23/38, 61 %), and other phenotypes included optic neuritis (10/38, 26 %), transverse myelitis (3/38, 8 %), and neuromyelitis optica spectrum disorder (NMOSD) (2/38, 5 %). 12 of 36 (33 %) patients with all lumbar puncture (LP) data available had CSF eosinophils present, with eosinophil mean of 3 % and range from 1 % to 18 % of CSF while blood cells.

CONCLUSION

CSF eosinophils were present in one third of pediatric MOGAD patients, which is a higher rate than previously reported in either MOGAD or aquaporin-4 antibody positive NMOSD cohorts. Understanding the CSF composition of pediatric MOGAD patients helps to facilitate more prompt diagnosis and treatment and may shed light onto underlying pathologic mechanisms of disease with the goal to inform future therapeutic targets.

Marked central canal T2-hyperintensity in MOGAD myelitis and comparison to NMOSD and MS

OBJECTIVE

To assess marked central canal T2-hyperintensity in patients with myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) myelitis compared to myelitis patients with aquaporin-4-antibody-positive neuromyelitis optica spectrum disorder (AQP4 + NMOSD) and multiple sclerosis (MS).

MATERIAL/METHODS

Two blinded raters evaluated spinal cord magnetic resonance imaging (MRIs) of myelitis patients with MOGAD (n = 63), AQP4 + NMOSD (n = 37), and MS (n = 26), assessing for marked central canal T2-hyperintensity and its evolution. If there were conflicting results, a third neurologist assessed the MRI.

RESULTS

Marked central canal T2-hyperintensity was more frequent in patients with MOGAD (18/63[29%]) than MS (1/26[4%]; p = 0.01) myelitis but did not differ from AQP4 + NMOSD (13/37[35%]; p = 0.49). Marked central canal T2-hyperintensity had completely resolved on follow-up axial MRI for most MOGAD (12/14[86%]) and AQP4 + NMOSD (10/10[100%]; p = 0.49) patients.

CONCLUSIONS

Marked central canal T2-hyperintensity is a common transient radiologic accompaniment of MOGAD and AQP4 + NMOSD myelitis, but not MS myelitis.

MOG encephalomyelitis: distinct clinical, MRI and CSF features in patients with longitudinal extensive transverse myelitis as first clinical presentation

Background

Based on clinical, immunological and histopathological evidence, MOG-IgG-associated encephalomyelitis (MOG-EM) has emerged as a distinct disease entity different from multiple sclerosis (MS) and aquaporin-4-antibody-positive neuromyelitis optica spectrum disorder (NMOSD). MOG-EM is associated with a broader clinical phenotype including optic neuritis, myelitis, brainstem lesions and acute disseminated encephalomyelitis with a substantial clinical and radiological overlap to other demyelinating CNS disorders.

Objective

To evaluate common clinical, MRI and CSF findings, as well as therapy responses in patients with longitudinal extensive transverse myelitis (LETM) as initial clinical presentation of MOG-EM.

Methods

After excluding patients with a known diagnosis of MS, we identified 153 patients with myelitis of which 7 fulfilled the inclusion criteria and were investigated for MRI, CSF and clinical parameters.

Results

Patients with LETM as first clinical presentation of MOG-EM display similar characteristics, namely a lack of gadolinium-enhancement in spinal cord MRI, marked pleocytosis, negative oligoclonal bands, a previous history of infections/vaccinations and response to antibody-depleting treatments for acute attacks and long-term treatment.

Conclusions

We identify common pathological findings in patients with LETM as first clinical presentation of MOG-EM which distinguishes it from other forms of LETM and should lead to testing for MOG-IgG in these cases.

Myelin Oligodendrocyte Glycoprotein Antibody Associated Transverse Myelitis

Antibodies against myelin oligodendrocyte glycoprotein cause inflammatory lesions of central myelin - in optic nerves, of the brainstem, and spinal cord. There are characteristic changes of CNS white matter, protein-cytological association in cerebrospinal fluid, MOG IgG antibodies, a very important differential diagnosis and a relatively mild course.

Antineutrophil cytoplasmic antibodies in patients with idiopathic inflammatory-demyelinating diseases

OBJECTIVE

We assessed the clinical significance of antineutrophil cytoplasm antibodies (ANCA) in patients with idiopathic inflammatory-demyelinating disease (IIDD).

METHODS

A consecutive cohort of 269 subjects with IIDD and 595 controls was analyzed retrospectively.

RESULTS

Among all subjects, ANCA positivity rates were low [9.5% in a perinuclear pattern (pANCA) and 2.3% in a cytoplasmic pattern (cANCA)]. One of the 117 patients with multiple sclerosis (MS) had cANCA and 2 had pANCA. Ten patients with neuromyelitis optica (NMO; 13.9%) had pANCA and 3 (4.2%) had cANCA. Four patients with recurrent longitudinal extensive transverse myelitis (RLETM; 19.0%) had pANCA and 1 (4.8%) had cANCA. In monophasic TM, 22.9% were pANCA seropositive. Among patients with brainstem syndromes, 14.3% were pANCA seropositive. Patients with NMO, RLETM or monophasic TM had higher pANCA levels than patients with MS. There was a positive association between spinal cord (SC) lesions and ANCA, and especially between longitudinal extensive transverse myelitis and ANCA. Among anti-aquaporin 4 antibody-positive patients, ANCA-positive patients (n = 16) were older and had higher Expanded Disability Status Scale scores, more antinuclear antibodies, longer SC lesions and fewer brain abnormalities than the ANCA-negative patients (n = 68). In the NMO subgroup, ANCA-positive patients were older and had more antinuclear antibodies and longer SC lesions than ANCA-negative patients.

CONCLUSION

Among the IIDDs, we found a higher occurrence of ANCA in patients with NMO spectrum disorders than in patients with MS. Therefore, ANCA is another interesting marker of autoimmunity in IIDD patients, especially those with anti-aquaporin 4 antibody.

Transverse myelitis in antiphospholipid antibody negative systemic lupus erythematosus

Acute transverse myelitis is a well known neurological complication occurring in systemic lupus erythematosus. Many prior studies have shown a link between transverse myelitis and the presence of antiphospholipid antibodies. Earlier theories have linked thrombotic tendency to be the culprit in such manifestations but currently there is evidence to support other causative mechanisms. A case of a young female diagnosed as systemic lupus erythematosus has been reported who presented with acute transverse myelitis and was found to be seronegative for antiphospholipid antibody. It is important to pay heed to and accordingly treat complications like acute transverse myelitis that occur regardless of antiphospholipid antibody positivity in a systemic lupus erythematosus setting.

Neuromyelitis optica IgG status in acute partial transverse myelitis

BACKGROUND

Neuromyelitis optica (NMO) IgG is a specific marker for NMO. Furthermore, a high proportion of patients with longitudinally extensive transverse myelitis (characterized by spinal cord lesions extending 3 vertebral segments or more on magnetic resonance imaging) are seropositive for NMO-IgG and are considered to have a limited form of NMO. The NMO-IgG status in mild cases of acute partial transverse myelitis asociated with minimal magnetic resonance imaging abnormalities (spinal cord lesions <2 vertebral segments on magnetic resonance imaging) is unknown.

OBJECTIVE

To investigate the NMO-IgG status of patients with acute partial transverse myelitis and a normal cerebral magnetic resonance image.

DESIGN

Observational, retrospective consecutive case series with longitudinal follow-up.

SETTING

Allegheny Multiple Sclerosis Treatment Center.

PATIENTS

Three groups of patients were tested for NMO-IgG. Group 1 consisted of 22 patients with acute partial transverse myelitis, group 2 consisted of 4 patients with definite NMO (by 1999 criteria of Wingerchuk et al), and group 3 consisted of 6 patients with definite multiple sclerosis.

MAIN OUTCOME MEASURE

NMO-IgG status. A commercially available assay for NMO antibodies was performed at the Mayo Clinic. Testing was performed during the convalescent stage of the illness.

RESULTS

Of the 22 patients with acute partial transverse myelitis, only 1 was seropositive for NMO-IgG at presentation. This patient subsequently developed recurrent episodes of longitudinally extensive transverse myelitis that are typicaly seen in association with NMO-IgG. Three of the 4 patients meeting criteria for NMO were seropositive. None of the patients with multiple sclerosis had NMO-IgG detected.

CONCLUSION

NMO-IgG is rarely encountered in patients with acute partial transverse myelitis, which is in sharp contrast to the high frequency of this antibody in patients with NMO and longitudinally extensive transverse myelitis.

Cytomegalovirus-associated transverse myelitis in a non-immunocompromised patient

Cytomegalovirus (CMV)-associated transverse myelitis is rare in immunocompetent patients. The case of a 54-year-old man is reported here who developed acute transverse myelitis with cerebrospinal fluid (CSF) alterations, suggesting a central nervous system infection. CMV-IgM positivity in serum and CMV isolated from blood, positive CMV PCR and positivity for pp65 antigen in blood, without viral antigens in the CSF and a positive response to therapy with ganciclovir (followed by progressive improvement) supported the diagnosis.