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Cureus
Cureus
2168-8184
Cureus
2168-8184
Cureus Palo Alto (CA)

10.7759/cureus.67408
Neurology
Ophthalmology
Neuromyelitis Optica: A Peek Into the Brain Through the Eyes
Muacevic Alexander
Adler John R
Aher Priyanka S 1
Bhavsar Deepaswi 2
Toshniwal Sumit 2
Bora Riddhi A 2
Jagadish Rohan 1
1 Ophthalmology, Dr. D. Y. Patil Medical College and Hospital, Pune, IND
2 Ophthalmology, Dr. D. Y. Patil Medical College, Hospital and Research Center, Pune, IND
Deepaswi Bhavsar deepaswibhavsar@gmail.com
21 8 2024
8 2024
16 8 e6740821 8 2024
Copyright © 2024, Aher et al.
2024
Aher et al.
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License CC-BY 4.0., which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
This article is available from https://www.cureus.com/articles/280614-neuromyelitis-optica-a-peek-into-the-brain-through-the-eyes
A rare demyelinating syndrome, known as neuromyelitis optica, is characterized by optic neuritis and transverse myelitis. A 27-year-old female presented to the eye department, with complaints of sudden progressive diminution of vision in both eyes (left eye more than right eye), acutely not being able to move both her eyes, double vision on lateral gazes with chronic dryness and irritation. Examination revealed restricted extraocular movements in all gazes. Magnetic resonance imaging of orbit showed retrobulbar optic neuritis. Blood tests revealed positive neuromyelitis optica myelin oligodendrocyte glycoprotein antibodies after which diagnosis of neuromyelitis optica was made.

sjogrens syndrome
demyelinating syndrome
optic neuritis
nmo-igg antibodies
neuromyelitis optica spectrum disorder (nmosd)
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pmcIntroduction

A rare demyelinating syndrome, known as neuromyelitis optica (NMO), is characterized by optic neuritis and transverse myelitis. First considered as a variant of multiple sclerosis (MS), it is now considered as an entirely different condition. Identification of aquaporin-4 (AQP4) antibody in the serum has a very high specificity [1]. Thus, the target of the NMO antibody is the AQP4. Neutrophils and eosinophils play a major contributory role in the tissue damage. NMO and spectrum disorders (NMOSD), also known as Devic disease, constitute 13.9% of all demyelinating disorders, with a prevalence of 2.6/100,000 [2].

One important subset of NMO spectrum disorder is those patients who are known to test positive for myelin oligodendrocyte glycoprotein (MOG) antibody. As with NMO, it includes optic neuritis, myelitis, and brainstem syndromes, though there are subtle differences between the two conditions. Optic neuritis in MOG antibody-associated disease often involves a long segment of the optic nerve and can present with disc edema, with myelitis often involving lower segments of the spinal cord than in AQP4 antibody disorder. 

NMOSD is a relapsing condition consisting of optic neuritis, myelitis, or area postrema syndrome. Optic neuritis in NMO is severe, commonly bilateral, and the recovery is not always complete. NMO can present as acute isolated optic neuritis at initial presentation [3]. Intractable hiccups and nausea as initial presenting symptoms have been reported in 43% of cases [4] of NMO patients, positive for anti-AQP4/NMO-IgG antibodies [5-7]. There is a “rim and rosette” pattern of immune complexes in the NMO lesion which is a result of complement activation at the site of the AQP4 protein.

Longitudinally extensive myelitis (LETM) is another hallmark of NMO. LETM is lesions including three or more vertebral segments. LETM or more limited TM starting in the cervical spine and reaching into the brainstem may lead to respiratory failure and/or persistent intractable hiccups and nausea, both of which are regarded as typical for NMO [8,9]. Myelitides may involve motor, sensory, and/or bowel and bladder functions. Brainstem symptoms present as area postrema syndrome which includes intractable nausea and vomiting, hiccupping. Other symptoms include double vision, dysphagia, and respiratory compromise.

Key diagnostic test of NMO antibody has a sensitivity of 70%-80% and specificity close to 100%. Patients with NMO often have antibodies positive for other conditions like Sjogren's syndrome or Lupus, suggesting two coexisting autoimmune syndromes. Cerebrospinal fluid in NMO shows mile elevation in white blood cells, and the presence of oligoclonal bands in 10% of cases [10].

The treatment approach in NMOSD and MOG antibody disease is almost identical which includes treatment of relapse, prevention of relapse, and treatment of chronic symptoms. Attack of NMOSD is treated promptly and aggressively with Intravenous methylprednisolone for a period of five days followed by prednisone tapering. Plasmapheresis or intravenous immunoglobulin may be used in some unresponsive patients with relapses who have incompletely recovered after steroid treatment. Plasmapheresis has been shown to bring a better outcome when used earlier in the course [11].

Case presentation

A 27-year-old female, not a known case of any systemic illness, who was admitted to the neurology ward was referred to the eye OPD with not being able to move both eyes, associated with a binocular double vision on trying to move her eyes and diminution of vision in the left eye more than right eye for four days. These symptoms were sudden and progressive, not associated with pain. She also complained of chronic irritation and dryness in her eyes. She was admitted to the neurology ward in view of right-sided weakness, difficulty in walking, and numbness progressing over four days, with difficulty in speaking, and excessive sleeping associated with flexor spasms. She also had tingling sensations intermittently over her limbs. She had no bowel and bladder complaints, but she did complain of frequent hiccups. She had similar complaints three months back for which she had taken a course of intravenous steroids for three days, followed by oral steroids after which her symptoms had partially resolved. There was no complaint of difficulty in closing eyelids, flashes, or floaters.

On evaluation, the best corrected visual acuity in the right eye was 6/60, and in the left eye was 1/60 recorded on Snellen’s chart. Color vision was impaired in the left eye. Extraocular movements in both eyes were limited in all quadrants as shown in Figure 1.

Figure 1 Limited extraocular movements of both the eyes in all the directions (arrows).

On anterior segment examination, there was mild diffuse congestion in both eyes with grade 2 relative afferent pupillary defect (RAPD) in the left eye. Both eye fundus showed no abnormality on indirect ophthalmoscope and slit lamp examination. Power was decreased in all four limbs (4/5). Sensory examination showed no abnormality. Cerebellar examination showed ataxia.

Magnetic resonance imaging (MRI) of the orbit revealed edematous left optic nerve. T2/FLAIR showed a hyperintense signal suggestive of left optic neuritis as shown in Figure 2.

Figure 2 MRI showing left optic neuritis.

MRI spine was suggestive of paraspinal muscle spasm with mild posterior bulge at L5-S1 levels indenting the thecal sac. White blood cell count revealed increased ratio of neutrophils with 79% (normal range - 40%-60%). The rest of the blood counts were within normal range. The visual evoked potential test showed pattern reversal with prolonged P100 wave latency suggestive of anterior pathway defect.

The patient was provisionally diagnosed with MS and started on 1 g intravenous methylprednisolone for three days. As there was no sufficient improvement symptomatically, more investigations were done which revealed positive NMO MOG antibodies in the blood, and ACE levels were elevated. P-ANCA, C-ANCA were negative. The cerebrospinal fluid examination had the presence of oligoclonal antibodies. She had to be started on plasmapheresis alternate day five cycles. She was also given 1 g of rituximab over 24 hours prior to discharge. The patient showed improvement symptomatically. She was able to walk without support. Her vision improved to 6/60 in the left eye. She was discharged on oral prednisolone 40 mg as maintenance therapy for one month and called for one monthly follow-up.

Discussion

NMO is an antibody-mediated disease involving the central nervous system. this disease was initially thought to be a severe form of optico-spinal MS [12]. with the identification of AQP4 antibodies in patients with NMO, it can be differentiated from MS. These antibodies are present in other tissues including collecting ducts of the kidneys, parietal cells of the stomach, secretory glands, airways as well as skeletal muscles but they are spared in this disease due to local complement inhibitors which are absent in the brain [13,14].

In the above-mentioned case, the patient presented with symptoms that included diminution of vision in both eyes, limited restriction of movement of both eyes in all gazes, and weakness of limbs. These symptoms are present in MS as well, the patient was initially diagnosed with MS. The presence of AQP4 antibodies and oligoclonal antibodies in CSF confirmed the diagnosis of this patient as NMOSD. In this patient, she responded better with plasmapheresis along with steroids instead of steroids alone and had to be kept on long-term oral steroids. Rituximab was given as an immunosuppressive therapy to prevent relapses, and the patient had to be kept on regular follow-up. 

Conclusions

NMO can present as an acute onset of limitation of extraocular movements and a decrease in visual acuity. Detailed ophthalmological as well as neurological evaluation has to be done in such patients. MS is the most common diagnosis suspected in patients presenting with the above-mentioned complaints. The presence of AQP4 antibodies in blood, the presence of oligoclonal antibodies on cerebrospinal fluid examination, and correlation with clinical features were the most important diagnostic criteria in this patient. Symptoms improve with treatment, majorly with plasmapheresis and intravenous corticosteroids, but it is a recurrent disease, and the patient has to be kept on long-term oral steroids with regular follow-up and immediate response in case of recurrent acute episodes.

Disclosures

Author Contributions

Human subjects: Consent was obtained or waived by all participants in this study.

Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following:

Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work.

Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work.

Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work.

Concept and design:  Priyanka S. Aher, Deepaswi Bhavsar, Sumit Toshniwal, Riddhi A. Bora, Rohan Jagadish

Acquisition, analysis, or interpretation of data:  Priyanka S. Aher, Deepaswi Bhavsar, Sumit Toshniwal, Riddhi A. Bora, Rohan Jagadish

Drafting of the manuscript:  Priyanka S. Aher, Deepaswi Bhavsar, Sumit Toshniwal, Riddhi A. Bora, Rohan Jagadish

Critical review of the manuscript for important intellectual content:  Priyanka S. Aher, Deepaswi Bhavsar, Sumit Toshniwal, Riddhi A. Bora, Rohan Jagadish

Supervision:  Priyanka S. Aher, Deepaswi Bhavsar, Sumit Toshniwal, Riddhi A. Bora, Rohan Jagadish
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References

1 Specificity and sensitivity of aquaporin 4 antibody detection tests in patients with neuromyelitis optica: a meta-analysis Mult Scler Relat Disord Ruiz-Gaviria R Baracaldo I Castañeda C Ruiz-Patiño A Acosta-Hernandez A Rosselli D 345 349 4 2015 26195055
2 Prevalence and patterns of demyelinating central nervous system disorders in urban Mangalore, South India Mult Scler Pandit L Kundapur R 1651 1653 20 2014 24493471
3 MRI characteristics of NMO, MOG and MS related optic neuritis Semin Ophthalmol Winter A Chwalisz B 333 342 35 2020 33395326
4 The clinical course of neuromyelitis optica (Devic's syndrome) Neurology Wingerchuk DM Hogancamp WF O'Brien PC Weinshenker BG 1107 1114 53 1999 10496275
5 Intractable hiccup and nausea in neuromyelitis optica with anti-aquaporin-4 antibody: a herald of acute exacerbations J Neurol Neurosurg Psychiatry Takahashi T Miyazawa I Misu T 1075 1078 79 2008 18420727
6 The spectrum of neuromyelitis optica Lancet Neurol Wingerchuk DM Lennon VA Lucchinetti CF Pittock SJ Weinshenker BG 805 815 6 2007 17706564
7 Intractable hiccup and nausea with periaqueductal lesions in neuromyelitis optica Neurology Misu T Fujihara K Nakashima I Sato S Itoyama Y 1479 1482 65 2005 16275842
8 Intractable vomiting as the initial presentation of neuromyelitis optica Ann Neurol Apiwattanakul M Popescu BF Matiello M 757 761 68 2010 21031587
9 Revised diagnostic criteria for neuromyelitis optica Neurology Wingerchuk DM Lennon VA Pittock SJ Lucchinetti CF Weinshenker BG 1485 1489 66 2006 16717206
10 International consensus diagnostic criteria for neuromyelitis optica spectrum disorders Neurology Wingerchuk DM Banwell B Bennett JL 177 189 85 2015 26092914
11 Immunotherapies in neuromyelitis optica spectrum disorder: efficacy and predictors of response J Neurol Neurosurg Psychiatry Stellmann JP Krumbholz M Friede T 639 647 88 2017 28572277
12 Neuromyelitis optica spectrum disorders Clin Med (Lond) Huda S Whittam D Bhojak M Chamberlain J Noonan C Jacob A 169 176 19 2019 30872305
13 Aquaporins in clinical medicine Annu Rev Med Verkman AS 303 316 63 2012 22248325
14 Role of membrane complement regulators in neuromyelitis optica Multiple Sclerosis J Saadoun S Papadopoulos MC 1644 1654 21 2015
