Myelin Oligodendrocyte Glycoprotein Antibody (MOG-IgG)-Positive Optic Perineuritis

MOG Antibody Disease: Nuances in Presentation, Diagnosis, and Management

PURPOSE OF REVIEW

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is a distinct neuroinflammatory condition characterized by attacks of optic neuritis, transverse myelitis, and other demyelinating events. Though it can mimic multiple sclerosis and neuromyelitis optica spectrum disorder, distinct clinical and radiologic features which can discriminate these conditions are now recognized. This review highlights recent advances in our understanding of clinical manifestations, diagnosis, and treatment of MOGAD.

RECENT FINDINGS

Studies have identified subtleties of common clinical attacks and identified more rare phenotypes, including cerebral cortical encephalitis, which have broadened our understanding of the clinicoradiologic spectrum of MOGAD and culminated in the recent publication of proposed diagnostic criteria with a familiar construction to those diagnosing other neuroinflammatory conditions. These criteria, in combination with advances in antibody testing, should simultaneously lead to wider recognition and reduced incidence of misdiagnosis. In addition, recent observational studies have raised new questions about when to treat MOGAD chronically, and with which agent. MOGAD pathophysiology informs some of the relatively unique clinical and radiologic features which have come to define this condition, and similarly has implications for diagnosis and management. Further prospective studies and the first clinical trials of therapeutic options will answer several remaining questions about the peculiarities of this condition.

MOG antibody-associated optic neuritis

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a demyelinating disorder, distinct from multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). MOGAD most frequently presents with optic neuritis (MOG-ON), often with characteristic clinical and radiological features. Bilateral involvement, disc swelling clinically and radiologically, and longitudinally extensive optic nerve hyperintensity with associated optic perineuritis on MRI are key characteristics that can help distinguish MOG-ON from optic neuritis due to other aetiologies. The detection of serum MOG immunoglobulin G utilising a live cell-based assay in a patient with a compatible clinical phenotype is highly specific for the diagnosis of MOGAD. This review will highlight the key clinical and radiological features which expedite diagnosis, as well as ancillary investigations such as visual fields, visual evoked potentials and cerebrospinal fluid analysis, which may be less discriminatory. Optical coherence tomography can identify optic nerve swelling acutely, and atrophy chronically, and may transpire to have utility as a diagnostic and prognostic biomarker. MOG-ON appears to be largely responsive to corticosteroids, which are often the mainstay of acute management. However, relapses are common in patients in whom follow-up is prolonged, often in the context of early or rapid corticosteroid tapering. Establishing optimal acute therapy, the role of maintenance steroid-sparing immunotherapy for long-term relapse prevention, and identifying predictors of relapsing disease remain key research priorities in MOG-ON.

The crucial role of gadolinium-enhanced MRI in a case of amaurosis fugax - a case report and literature review

Optic perineuritis is the inflammation of the optic nerve sheath. This affliction can lead to visual field impairment and other signs and symptoms related to the orbital space, such as pain, disc edema, ophthalmoplegia, proptosis. However, not all patients present with such suggestive symptoms, requiring a thorough assessment. We report the case of a young male admitted to our hospital for recurrent episodes of monocular blindness. Amaurosis fugax is a well-known presentation of transient ischemic attacks (TIA) and it was ruled out. Gadolinium-enhanced MRI revealed a typical aspect of optic perineuritis. It was mandatory to consider all possible causes of secondary optic perineuritis as they all represent serious clinical conditions, even if the idiopathic form is more frequent. The clinical and paraclinical evaluation of the patient excluded an underlying disease and primary optic perineuritis was diagnosed. Corticosteroid therapy is usually curative and a course of methylprednisolone was initiated for our patient with good outcome. However, response to treatment is not diagnostic as both primary and secondary optic perineuritis are normally responsive, hence thorough differential diagnosis is necessary.

Beyond Myelin Oligodendrocyte Glycoprotein and Aquaporin-4 Antibodies: Alternative Causes of Optic Neuritis

Optic neuritis (ON) is the most common cause of vision loss in young adults. It manifests as acute or subacute vision loss, often accompanied by retrobulbar discomfort or pain during eye movements. Typical ON is associated with Multiple Sclerosis (MS) and is generally mild and steroid-responsive. Atypical forms are characterized by unusual features, such as prominent optic disc edema, poor treatment response, and bilateral involvement, and they are often associated with autoantibodies against aquaporin-4 (AQP4) or Myelin Oligodendrocyte Glycoprotein (MOG). However, in some cases, AQP4 and MOG antibodies will return as negative, plunging the clinician into a diagnostic conundrum. AQP4- and MOG-seronegative ON warrants a broad differential diagnosis, including autoantibody-associated, granulomatous, and systemic disorders. These rare forms need to be identified promptly, as their management and prognosis are greatly different. The aim of this review is to describe the possible rarer etiologies of non-MS-related and AQP4- and MOG-IgG-seronegative inflammatory ON and discuss their diagnoses and treatments.

An update on optic neuritis

Optic neuritis (ON) is the most common cause of subacute optic neuropathy in young adults. Although most cases of optic neuritis (ON) are classified as typical, meaning idiopathic or associated with multiple sclerosis, there is a growing understanding of atypical forms of optic neuritis such as antibody mediated aquaporin-4 (AQP4)-IgG neuromyelitis optica spectrum disorder (NMOSD) and the recently described entity, myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). Differentiating typical ON from atypical ON is important because they have different prognoses and treatments. Findings of atypical ON, including severe vision loss with poor recovery with steroids or steroid dependence, prominent optic disc edema, bilateral vision loss, and childhood or late adult onset, should prompt serologic testing for AQP4-IgG and MOG-IgG. Although the traditional division of typical and atypical ON can be helpful, it should be noted that there can be severe presentations of otherwise typical ON and mild presentations of atypical ON that blur these traditional lines. Rare causes of autoimmune optic neuropathies, such as glial fibrillary acidic protein (GFAP) and collapsin response-mediator protein 5 (CRMP5) autoimmunity also should be considered in patients with bilateral painless optic neuropathy associated with optic disc edema, especially if there are other accompanying suggestive neurologic symptoms/signs. Typical ON usually recovers well without treatment, though recovery may be expedited by steroids. Atypical ON is usually treated with intravenous steroids, and some forms, such as NMOSD, often require plasma exchange for acute attacks and long-term immunosuppressive therapy to prevent relapses. Since treatment is tailored to the cause of the ON, elucidating the etiology of the ON is of the utmost importance.

Systematic Review of Treatment Options and Therapeutic Responses for Lesions of the Sella and Orbit: Evidence-Based Recommendations

OBJECTIVE

Inflammatory pathologies of the sella and orbit are rare but require prompt diagnosis to initiate effective treatment. Because uniform recommendations for treatment are currently lacking, we performed an evidence-based review to identify recommendations.

METHODS

We performed a literature search of the PubMed, Embase, and Web of Science databases to identify papers evaluating treatment of inflammatory pathologies of the sella and orbit. We used PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to define recommendations, specifically examining aggregated sample sizes, disease-specific patient follow-up, and clinical trials focused on inflammatory diseases of the sella and orbit.

RESULTS

A total of 169 studies were included and organized by disease pathology. Treatments for various pathologies were recorded. Treatment options included surgery, radiation, steroids, targeted treatments, immunomodulators, intravenous immune globulin, and plasmapheresis. Steroids were the most often employed treatment, second-line management options and timing varied. Pathological diagnosis was highly associated with treatment used. Most evidence were level 3 without available control groups, except for 13 trials in neuromyelitis optica with level 1 or 2 evidence.

CONCLUSIONS

This is the first evidence-based review to provide recommendations on specific treatments for pathologies of the orbit and sella. The reported data may be useful to help guide randomized clinical trials and provide resource for clinical management decisions based on the available evidence.

[Typical and atypical optic neuritis]

Optic neuritis (ON) is one of the most common neuro-ophthalmic causes of vision loss worldwide. Demyelinating ON can be idiopathic or be one of the symptoms of autoimmune demyelinating diseases of the central nervous system (CNS) such as multiple sclerosis (MS), neuromyelitis optica spectrum disorders (NMOSD), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Demographic, clinical and radiological signs of ON in these CNS diseases have differences. In this regard, typical and atypical ON are currently distinguished. Recognizing the clinical features that differentiate typical MS-associated ON from atypical ON in NMOSD and MOGAD is important for choosing the correct disease management and treatment strategy. This review summarizes the data from clinical, laboratory, instrumental methods of management used for the differential diagnosis of optic neuritis.

Optic perineuritis

PURPOSE OF REVIEW

This review paper aims at discussing pathogenesis, etiology, clinical features, management, and prognosis of OPN.

RECENT FINDINGS

Optic perineuritis (OPN) is an inflammatory process primarily involving the optic nerve sheath. Clinically, OPN usually presents with unilateral, gradual decline of visual function, eye pain, and/or pain on eye movements, disc edema and various features of optic nerve dysfunction, including visual field defects. It can mimic typical optic neuritis. In most cases of OPN, the disease is isolated with no specific etiology being identified, however, it can also occur secondary to a wide range of underlying systemic diseases. OPN is clinically diagnosed and radiologically confirmed based on the finding of circumferential perineural enhancement of the optic nerve sheath on magnetic resonance imaging (MRI).

SUMMARY

Unlike optic nerve, OPN is not typically self-limited without treatment. High-dose oral corticosteroids are the mainstay of treatment in OPN. The initiation of therapy usually causes rapid and dramatic improvement in signs and symptoms. In general, OPN usually has a relatively good visual prognosis, which is influenced by delays between the onset of visual loss and the initiation of steroid therapy as well as the presence of underlying systemic diseases.

Recurrent Optic Perineuritis With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease Complicated With Granulomatous Polyangiitis

Optic perineuritis (OPN) is an intraorbital inflammatory disease that targets the optic nerve sheath, which can cause severe vision loss. OPN has been recently reported to be sometimes caused by myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). MOGAD is rarely reported to be complicated with other autoimmune diseases. We report the first rare case of MOG-associated OPN complicated with granulomatous with polyangiitis (GPA).

The vision loss, in this case, was initially considered to be caused by cavernous sinusitis in GPA. However, she was diagnosed with MOGAD with serial MRI findings and positive MOG antibody and had been successfully treated with glucocorticoid and tocilizumab for one and half years. This case emphasized the importance of evaluating the MOG antibody in a patient with recurrent OPN, complicated with vasculitis.

[Right optic perineuritis and myelitis 6 years following left optic perineuritis in anti-myelin oligodendrocyte glycoprotein-associated disorder: a case report]

We report a patient with myelin oligodendrocyte glycoprotein (MOG) antibody positivity who manifested myelitis with right optic perineuritis (OPN) 6 years following left OPN. A 45-year-old man treated 6 years previously for left OPN developed ascending numbness in both legs, urinary dysfunctions, and constipation. Neurologic examination disclosed bilateral hypesthesia extending downward over the chest from the T8 level. No motor weakness was evident. Visual field testing showed dense peripheral constriction with intact central vision on the right and a smaller superior scotoma on the left. Visual acuity and funduscopic findings were normal. Results of routine serologic investigations and autoimmune antibody titers, including those of anti-aquaporin 4 antibody, were within normal limits, except that both serum and cerebrospinal fluid were positive for anti-MOG antibody. MRI displayed a longitudinal cord lesion extending from T2 to T9, as well as optic nerve sheath enhancement characteristic of OPN. The patient was diagnosed with myelitis in addition to OPN, both resulting from MOG antibody-associated demyelination. Patients with myelitis, require careful assessment of visual acuity and visual fields to detect possible accompanying OPN and ON. We suspect that OPN in some other patients may likewise be caused by anti-MOG antibody.

Optic perineuritis: A Canadian case series and literature review

BACKGROUND

Optic perineuritis (OPN) is a rare orbital inflammatory disorder that primarily involves the optic nerve sheath (ONS). This study aimed to describe the clinical features of idiopathic OPN as well as OPN secondary to other infectious and inflammatory conditions in a Canadian case series as current literature on secondary OPN in Western countries is mostly limited to case reports.

METHODS

Retrospective case series of all patients seen in a tertiary neuro-ophthalmology practice with a diagnosis of OPN from 2014 to 2020.

RESULTS

A total of 21 patients (14 women, mean age 55.8) corresponding to 29 eyes with OPN were identified. Fifteen cases were associated with inflammatory or infectious conditions and only 6 were idiopathic. All idiopathic cases were unilateral. The most common secondary causes of OPN were anti-myelin oligodendrocyte glycoprotein (MOG) antibody disease (n = 4), syphilis (n = 3), sarcoidosis (n = 3), and giant cell arteritis (n = 3). At initial presentation, best-corrected visual acuity (BCVA) was 20/20 or better in 24% (n = 7) and visual field mean deviation (VF MD) was better than -5 dB in 34% of eyes (10/29). Treatment consisted of intravenous penicillin for syphilitic OPN and high-dose corticosteroids followed by oral taper with or without immunosuppressive therapy for non-syphilitic OPN. BCVA improved in 34% (10/29) and VF MD improved in 45% (13/29) eyes.

CONCLUSION

OPN primarily occurred in association with systemic inflammatory conditions, especially in bilateral cases. Syphilis must be ruled out in all patients. Anti-MOG antibody disease is an important, newly recognized secondary cause of OPN, and serologic testing should be included in the investigation of all patients with OPN.

Optic Perineuritis and Its Association With Autoimmune Diseases

Background: Optic perineuritis (OPN) is a special optic neuropathy that has a distinct etiology from neuromyelitis optica spectrum disorders (NMOSDs) or multiple sclerosis (MS)-related optic neuritis (ON). The mechanisms of how this inflammation developed and invaded the nerve sheath remain unknown. This study is aimed to analyze the etiology and different clinical characteristics of OPN in a Chinese patient population. Methods: Neuro-ophthalmological examination, orbit magnetic resonance imaging (MRI) and a series of blood samples were used in this retrospective observational cohort study to compare characteristics of OPN with idiopathic demyelination optic neuritis (IDON). Results: Forty-four OPN cases (74 eyes) and 61 IDON cases (78 eyes) were analyzed. OPN cases included 33 cases (59 eyes) were associated with specific autoimmune diseases, 10 cases (13 eyes) were associated with infection diseases, 1 case was idiopathic disease. The causes of OPN with CTD were Graves' disease, Immunoglobulin G4-related disease (IgG-4 RD), granulomatosis with polyangiitis (GAP), systemic lupus erythematosus (SLE), Sarcoidosis, Rheumatoid arthritis, scleroderma, Behcet's disease, and gout. All patients received orbital MRI. Overall, 33 cases showed orbit fat infiltration. Specifically, nine cases with IgG-4 RD showed trigeminal nerve branch involvement, 12 cases with Graves' disease showed extraocular muscle belly enlargement, and 4 cases with GAP showed pterygopalatine fossa pseudotumor. Compared to IDON patients, OPN patients were older (p = 0.004) and more likely bilateral involvement 26 (78.79%) patients had bilateral involvement in OPN group vs. 17 (27.87%) in the IDON group (p < 0.001). Visual acuity scores using LogMAR testing was better in OPN patients compared to those with IDON, 0.55 ± 0.91 vs. 1.19 ± 1.24 (p < 0.001). Other ophthalmologic findings unique to the OPN group include 11 (33.33%) cases of ptosis, nine (27.27%) cases of diplopia, and 10 (30.30%) cases of exophthalmos, compared to zero cases of these conditions in the IDON group. Eight (13.11%) IDON patients also had multiple sclerosis (MS) and 7 (11.48%) patients had neuromyelitis which was significantly more than the zero patients in OPN group (p = 0.04). Conclusions: OPN had distinct etiologies and clinical characteristics from IDON and is more often associated with autoimmune diseases. Using OPN characteristics to diagnose autoimmune diseases should prove useful for clinicians when presented with patients that have multiorgan dysfunction that include ophthalmologic findings.

Anti-MOG associated disorder-Clinical and radiological characteristics compared to AQP4-IgG+ NMOSD-A single-center experience

BACKGROUND

The discovery of two immunoglobulin G (IgG) antibodies against aquaporin 4 (anti-AQP4) and myelin oligodendrocyte glycoprotein (anti-MOG) has led to the distinction of the disorders anti-AQP4 immunoglobulin G positive neuromyelitis spectrum disorder (AQP4-IgG+ NMOSD) and anti-MOG associated disorder (MOGAD). Different clinical and radiological features have been proposed to distinguish these two demyelinating CNS diseases.

METHODS

This is a single-center retrospective review at the University of Florida (UF) including all patients with the diagnostic code ICD G36 ("other acute disseminated demyelination") from October 2015 to January 2020 (n=141) and all charts included in the clinical NMOSD database of the UF Division of Neuroimmunology (n=36). A total of 151 cases were reviewed for presence of anti-MOG and anti-AQP4 antibodies and NMOSD diagnostic criteria. Differences in MOGAD and AQP4-IgG+ NMOSD were compared.

RESULTS

Of the 151 reviewed patient charts, 11 were consistent with MOGAD and 43 with AQP4-IgG+ NMOSD. Patients with MOGAD were significantly younger at symptom onset compared to patients with AQP4-IgG+ NMOSD (14 [1-33] years vs. 37 [6-82] years; p=0.005). In comparison with AQP4-IgG+ NMOSD, optic neuritis in MOGAD was more frequently associated with bilateral optic nerve involvement: (6/11 [54.5%] vs. 6/43 [13.9%]; p=0.009) and fundoscopic presence of optic disc edema (5/11 [45.5%] vs. 3/43 [7%]; p=0.006). Perineuritis was a common radiological feature in MOGAD (present in 4 cases). In case of myelitis, there was more frequent involvement of the conus medullaris in MOGAD (4/11 [36.4%] vs. 2/43 [4.7%]; p=0.012). Symptomatic cerebral syndrome with supratentorial white matter lesions was seen in MOGAD patients with pediatric onset (pediatric onset: 4/6 [66.7%] vs. adult onset: 0/5 [0%]. In MOGAD, evidence for combined central and peripheral demyelination and increased intracranial pressure was present in one patient each. A preceding inciting event (illness/postpartum) was more frequently identifiable in MOGAD (4/11 [36.4%] vs. 4/43 [7%]; p=0.045). Disability as calculated on the Expanded Disability Status Scale was less severe in MOGAD compared to AQP-IgG+ NMOSD (most severe presentation: 5 [2-7] vs. 7 [1-10]; p=0.015; most recent assessment: 2 [0-5] vs. 5 [0-10]; p=0.045) and patients were more likely to respond to treatment of acute attacks with corticosteroids and/or plasmapheresis (Clinical Global Impression-Global Change scale: 1 [1-4] vs. 3 [1-6]; p=0.001).

INTERPRETATION

The study confirms that simultaneous bilateral optic neuritis, presence of optic disc edema, transverse myelitis with conus involvement and a less severe disease course are distinctive features of MOGAD.

Ophthalmic manifestations of myelin oligodendrocyte glycoprotein-IgG-associated disorder other than optic neuritis: a systematic review

Background/Aims

Optic neuritis (ON) is the primary ophthalmic manifestation of myelin oligodendrocyte glycoprotein-IgG-associated disorder (MOGAD), but numerous reports have expanded the visual manifestations of this condition. The goal of this study was to synthesise the extensive literature on this topic to help ophthalmologists understand when testing for MOG-IgG should be considered.

Method

A systematic review of the English-language literature was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and searches were conducted using Ovid MEDLINE (from January 1, 1948 to April 1, 2020) and Ovid EMBASE (from January 1, 1947 to April 1, 2020). Inclusion criteria included studies describing non-isolated ON ophthalmic manifestations where cell-based assays were used for the detection of MOG antibodies.

Results

Fifty-one articles representing 62 patients with a median age of 32.0 (range 2–65), female gender (51%) and follow-up of 20.0 months (range: 1–240) were included. Twenty-nine patients had non-isolated ON afferent visual manifestations: uveitis, peripheral ulcerative keratitis, acute macular neuroretinopathy, neuroretinitis, venous stasis retinopathy, large preretinal macular haemorrhage, orbital inflammatory syndrome, orbital apex syndrome, optic perineuritis, papilloedema and homonymous visual field defects. Incomplete recovery of ON was associated with a case of Leber’s hereditary optic neuropathy. Efferent ophthalmic manifestations included cranial neuropathies, internuclear ophthalmoplegia, central nystagmus, saccadic intrusions and ocular flutter. Cranial nerve involvement was secondary to enhancement of the cisternal portion or brainstem involvement. All included cases were treated with corticosteroids with 31% of cases requiring additional immunosuppressive therapy.

Conclusions

MOGAD has been associated with various afferent and efferent ophthalmic manifestations apart from isolated ON. Awareness of these findings may result in earlier diagnosis and treatment.

Resolution of myelin oligodendrocyte glycoprotein (MOG)-IgG optic neuritis without treatment

BACKGROUND

Patients with MOG-IgG optic neuritis tend to present with severely comprised visual function during the acute phase of the disease. Treatment with corticosteroids is almost always used in the acute period to aid in visual recovery and there is limited data on the natural history without treatment.

METHODS

We present the case of a 45-year-old woman who developed right eye pain worse with eye movements and mildly blurred vision and was found to have optic disk edema with peripapillary hemorrhages. Her visual acuity was 20/20 and she had several depressed points on Humphrey visual field testing. Magnetic resonance imaging of the brain was normal and the orbits revealed very mild enhancement of the optic nerve/optic nerve sheath. MOG-IgG was positive in the serum (medium positivity). She was observed without treatment, the pain resolved and she felt her vision returned to normal within 2 months of onset.

CONCLUSIONS

MOG-IgG optic neuritis may present with relatively preserved visual function even at its nadir. Observation may be a reasonable strategy for these patients.