Comparison of clinical manifestations between patients with ocular myasthenia gravis and generalized myasthenia gravis

Low probability of myasthenia Gravis in patients presenting to neuro-ophthalmology clinic for evaluation of isolated ptosis

BACKGROUND

Concerning causes of ptosis, most notably third nerve palsy and Horner's syndrome, can be ruled out with normal ocular motility and pupillary examination. Myasthenia gravis (MG) however, rarely can present with ptosis as an isolated finding. We reviewed all patients presenting to tertiary neuro-ophthalmology practice with ptosis of unknown etiology to determine the frequency of MG.

METHODS

Retrospective chart review of patients referred to a tertiary neuro-ophthalmology practice with undifferentiated ptosis.

RESULTS

Sixty patients were included in the study. Twenty eight (47%) patients had ptosis along with various abnormalities of ocular motility and/or alignment and 32 (53%) had isolated unilateral ptosis defined as ptosis with absence of diplopia, or symptoms of generalized MG (GMG). Final diagnosis was aponeurotic ptosis due to levator palpebrae dehiscence in the majority (73%) of patients, while 10 (17%) were diagnosed with MG (6 with OMG, 4 with GMG). Diplopia was present in 9/10 patients with MG and 8/10 had abnormal ocular findings on clinical examination such as orbicularis oculi weakness, Cogan's lid twitch or fatiguability of ptosis on sustained upgaze. Only one patient referred for isolated unilateral ptosis was diagnosed with OMG and this patient had orbicularis oculi weakness.

CONCLUSIONS

None of the patients with isolated unilateral ptosis and otherwise normal examination had MG. All patients eventually diagnosed with MG had diplopia or orbicularis weakness on examination. Thus, the yield of investigating patients with isolated ptosis for MG is exceedingly low.

Epidemiology of Ocular Manifestations in Autoimmune Disease

The global prevalence of autoimmune diseases is increasing. As a result, ocular complications, ranging from minor symptoms to sight-threatening scenarios, associated with autoimmune diseases have also risen. These ocular manifestations can result from the disease itself or treatments used to combat the primary autoimmune disease. This review provides detailed insights into the epidemiological factors affecting the increasing prevalence of ocular complications associated with several autoimmune disorders.

Myasthenia Gravis-An Analysis of Multimodal Evoked Potentials

INTRODUCTION

The aim of this study is a comprehensive analysis of the parameters of exogenous evoked potentials (visual, brainstem auditory, and somatosensory) in patients with myasthenia gravis (MG), a prototype of both neuromuscular junction disease and autoimmune disease. The study also seeks to isolate electrophysiological changes that may indicate disorders within the central and/or peripheral nervous system.

METHODS

A total of forty-two consecutive patients with myasthenia gravis (24 women, 18 men) were included in the study. All of the patients underwent EP examination. MR images were also analyzed.

RESULTS

In the group of MG patients, the latency of P100 (113.9 ± 13.9; p < 0.0001) VEP, wave III (3.92 ± 0.29; p = 0.015), wave V (5.93 ± 0.32; <0.0001), interlatency III-V (2.00 ± 0.12; p < 0.0001), interlatency I-V (4.20 ± 0.28; p < 0.001) BAEP, and all components of SEP (N9, P10, N13, P16, N20, P22) were significantly longer. Mean wave I and V amplitude BAEP were relatively lower.

CONCLUSIONS

The results of the study suggest the presence of disturbances in the bioelectric activities of the central and peripheral nervous system in MG patients.

Ocular Manifestations in Colombian Patients with Systemic Rheumatologic Diseases

PURPOSE

To establish the prevalence of ocular involvement in a Colombian population with rheumatologic diseases.

DESIGN

Observational cross-sectional study.

METHODS

We included a probabilistic sample size of 797 patients who attended a rheumatologic disease center in Bogotá, Colombia. Statistical analysis with descriptive measures and Chi-square independence test between rheumatologic diseases and ophthalmological symptoms and diseases was performed.

RESULTS

Eighty-four percent of the population were women, and the mean age was 54.61± 15.64 years. The most common condition was rheumatoid arthritis (33.37%), followed by fibromyalgia (22.71%), Sjögren Syndrome (19.72%), and systemic lupus erythematosus (9.91%). Almost 7% of the patients presented polyautoimmunity. Thirty-five percent of the patients reported one or more ophthalmological symptoms, being dry eye sensation the most common (30.86%), followed by ocular pain (2.76%), red-eye, and decreased visual acuity (both 2.63%). Similarly, 21.45% of the patients presented one or more ophthalmological diagnoses, being keratoconjunctivitis sicca the most common (15.93%), followed by cataract, uveitis (1.38% each), and scleritis (1.25%).

CONCLUSION

Almost a third of the patients reported any ocular involvement. It is crucial to be aware of the most common ophthalmic manifestations among the different rheumatologic diseases in our population, to offer early specialist referral and timely treatment.

Pediatric Autoimmune Ocular Myasthenia Gravis: Evaluation of Presentation and Treatment Outcomes in a Large Cohort

BACKGROUND

In autoimmune myasthenia gravis (MG), autoantibodies target the neuromuscular junction. Ocular myasthenia gravis (OMG) is localized, affecting only extraocular and/or levator palpebrae muscles. OMG presents across all ages, varying in presentation, treatment modalities, and outcomes. Recently, there have been advances in MG/OMG treatment; their utilization and effectiveness are an important part of optimal disease management.

METHODS

We completed a retrospective chart review of children aged 18 years or younger with a confirmed diagnosis of OMG presenting from 2002 to 2019.

RESULTS

Forty-two patients were included with mean age at presentation of 8.5 years (2 to 18 years). Twenty-one patients (50%) had positive antibodies; 90% had acetylcholine receptor antibodies. Ten patients developed generalized symptoms with mean time to generalization of 13.6 months. Multiple logistic regression showed that older age of onset was a trend predictive factor (P = 0.054; odds ratio 1.17) for generalized disease. All patients were treated with pyridostigmine. Immunomodulating agents included steroids (15), mycophenolate mofetil (four), and intravenous immunoglobulin (one). Three patients underwent thymectomy. Twenty patients reached minimal manifestation status, and 12 achieved remission. Gender, race, and positive antibody status were not statistically significant predictors for advanced immunosuppressive therapy.

CONCLUSIONS

We summarize one of the largest cohorts of pediatric patients with OMG who have undergone up-to-date diagnostic and therapeutic regimens. The predictors of outcome and treatment pathway for OMG patients suggested by this report may be further elucidated by future prospective studies.

Ocular Myasthenia Gravis with Severe Blepharitis and Ocular Surface Disease: A Case Report

Ocular myasthenia gravis (OMG) is an autoimmune disease of the neuromuscular junction and commonly associated with other immune diseases. We describe a 16-year-old female who presented to our clinic with 1-month complaints of diplopia and strabismus, visual acuity deterioration, and ocular irritation. Her examination showed crossed diplopia and alternating exotropia of 25 prism diopters, severe blepharitis, conjunctival hyperemia, corneal pannus, epithelial irregularities, and subepithelial opacities. Workup included pediatric neurologic examination, laboratory tests, imaging, and electrophysiological tests. Diagnoses of OMG and blepharitis with ocular surface disease were made. Topical treatment included eyelid hygiene, tea tree oil scrubbing, topical steroids, and tacrolimus ointment. Systemic treatment included corticosteroids, pyridostigmine, azathioprine, intravenous immunoglobulins, amitriptyline, and doxycycline. Both diseases were refractory to intensive immunosuppressive treatment and had simultaneous relapses and an intertwined course. Our hypothesis is that a shared immune mechanism may be the cause of both OMG and ocular surface disease in our patient.

Maintenance immunosuppression in myasthenia gravis, an update

Therapies for myasthenia gravis (MG) include symptomatic and immunosuppressive/immunomodulatory treatment. Options for immunosuppression include corticosteroids, azathioprine, mycophenolate mofetil, cyclosporine, tacrolimus, methotrexate, rituximab, cyclophosphamide, eculizumab, intravenous immunoglobulin, subcutaneous immunoglobulin, plasmapheresis, and thymectomy. The practical aspects of long-term immunosuppressive therapy in MG are critically reviewed in this article. Application of one or more of these specific therapies is guided based on known efficacy, adverse effect profile, particular disease subtype and severity, and patient co-morbidities.

Update on ocular myasthenia gravis in Taiwan

Myasthenia gravis (MG) is an autoimmune disease involving the neuromuscular junction. Autoantibodies to the acetylcholine receptor or, less frequently, to muscle-specific kinase, attack against the postsynaptic junctional proteins, resulting in fluctuating and variable weakness of muscles. Extraocular, levator palpebrae superioris, and orbicularis oculi muscles are particularly susceptible. The majority of patients with MG present with purely ocular symptoms including ptosis and diplopia initially. About half of these patients progress to generalized disease within 2 years. The prevalence of MG in Taiwan is 140 per million with male to female ratio of 0.7. The incidence rate is higher in the elderly. Several immune-related diseases such as lymphoid malignancy, diabetes, and thyroid diseases are associated with MG in the national population-based studies in Taiwan. Ice pack test, rest test, Tensilon/neostigmine test, circulating antibody measurement, and electrophysiological studies are useful diagnostic tools with variable sensitivity and specificity. For the patients with ocular MG, acetylcholinesterase inhibitors are usually the first-line treatment. Corticosteroids and immunosuppressant could provide better disease control and may reduce the risk of conversion to generalized form although there is still some controversy. A thymectomy is also beneficial for ocular MG, especially in refractory cases. The correction of ptosis and strabismus surgery could improve the visual outcome but should be performed only in stable disease.

Diagnosis of myasthenia gravis: Comparison of anti-nicotinic acetyl choline receptor antibodies, repetitive nerve stimulation and Neostigmine tests at a tertiary neuro care centre in India, a ten year study

Anti-nicotinic AChR antibodies (Anti-nAChR antibodies), Repetitive Nerve Stimulation (RNS) and Neostigmine test are used for diagnosis of myasthenia gravis (MG). We compared their diagnostic agreement in a cohort of 486 MG patients over a period of ten years. Anti-nAChR antibodies, RNS and Neostigmine test showed positivity of 57.36%, 51.78%, and 93.4% respectively in ocular myasthenia and 93.77%, 82.35%, and 97.92% respectively in generalized myasthenia group. Neostigmine test showed higher positivity than anti-nAChR antibodies and RNS test in both groups. A marginal to fair agreement was observed between these tests highlighting their significance in the diagnosis of the disease.

Frontalis sling procedure for ocular myasthenia gravis

A 39-year-old woman was diagnosed with myasthenia gravis when she was 8 years old. Although many treatments – such as cholinesterase inhibitors and steroids – had been given to the patient, her condition did not improve sufficiently. As she demonstrated bilateral 3 mm levator function without any eye movement disturbances, bilateral frontalis sling procedures were performed with an autologous fascia lata. One year after the operation, the operated upper eyelids showed symmetrically appropriate heights with good functional outcome. A sling procedure with an autologous fascia lata was suitable for correcting poor levator function of an ocular myasthenia gravis case.