The effect of early prednisolone treatment on the generalization rate in ocular myasthenia gravis

Clinical Characteristics Associated With Secondary Generalization in Patients With Ocular Myasthenia Gravis: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Ocular myasthenia gravis (OMG) is an autoimmune disorder resulting in ocular symptoms such as diplopia and ptosis. The proportion of patients who convert to secondary generalized myasthenia gravis (SGMG) reported in the literature has been varied. The aim of this systematic review was to determine the clinical characteristics of patients with OMG and the proportion of SGMG conversion.

METHODS

We conducted an electronic database search for randomized controlled trials, prospective nonrandomized studies, observational studies, and retrospective studies in EMBASE, CENTRAL, MEDLINE, and Web of Science. We included studies with patients with OMG who initially presented with ocular symptoms and signs only and were seen in clinical practice, reporting on the characteristics and outcomes of SGMG. We excluded studies with pediatric and congenital myasthenia gravis populations. Eligible studies included articles written in any language and containing data on patients with OMG. The main outcome measured was the proportion of patients with OMG who converted to SGMG and risk factors associated with secondary generalization of OMG. Two independent reviewers screened titles and abstracts and extracted data from full texts, reporting findings according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The methodology was evaluated using the Joanna Briggs Institute critical appraisal forms. PROSPERO registration number: CRD2021285257.

RESULTS

Thirty-one studies were included in the quantitative and qualitative analysis. The proportion of generalization ranged from 11% to 84%. The pooled proportion was 39% (95% CI 32%-47%, I 2 = 95.86%, p < 0.001 unweighted, low certainty). The pooled risk ratio of female sex for conversion to SGMG was 1.06 (95% CI 0.96-1.17, I 2 = 0% p = 0.614, 21 studies included, very low certainty), and the pooled risk ratio of acetylcholine receptor (AChR) positivity was 1.30 (95% CI 1.05-1.56, I 2 = 0% p = 0.455, 16 studies included, very low certainty).

DISCUSSION

Risk factors such as female sex and anti-AChR positivity have been identified to have possible associations with SGMG, but there are not enough quality observational studies. There is a need for a prospective global database of patients with OMG, including all countries with different populations.

Development and Validation of a Nomogram for Predicting Generalization in Patients With Ocular Myasthenia Gravis

Background

This study aims to develop and validate a nomogram for predicting 1- and 2-year generalization probabilities in patients with ocular myasthenia gravis (OMG).

Methods

In total, 501 eligible patients with OMG treated at seven tertiary hospitals in China between January 2015 and May 2019 were included. The primary outcome measure was disease generalization. A nomogram for predicting 1- and 2-year generalization probabilities was constructed using a stepwise Cox regression model. Nomogram performance was quantified using C-indexes and calibration curves. Two-year cumulative generalization rates were analyzed using the Kaplan−Meier method for distinct nomogram-stratified risk groups. The clinical usefulness of the nomogram was evaluated using decision curve analysis (DCA).

Result

The eligible patients were randomly divided into a development cohort (n=351, 70%) and a validation cohort (n=150, 30%). The final model included five variables: sex, onset age, repetitive nerve stimulation findings, acetylcholine receptor antibody test results, and thymic status. The model demonstrated good discrimination (C-indexes of 0.733 and 0.788 in the development and validation cohorts, respectively) and calibration, with good agreement between actual and nomogram-estimated generalization probabilities. Kaplan−Meier curves revealed higher 2-year cumulative generalization rates in the high-risk group than that in the low-risk group. DCA demonstrated a higher net benefit of nomogram-assisted decisions compared to treatment of all patients or none.

Conclusion

The nomogram model can predict 1- and 2-year generalization probabilities in patients with OMG and stratified these patients into distinct generalization risk groups. The nomogram has potential to aid neurologists in selecting suitable patients for initiating immunotherapy and for enrolment in clinical trials of risk-modifying treatments.

Association of immunosuppression treatment with generalization among patients with ocular myasthenia gravis: a propensity score analysis

BACKGROUND

To analyze disease generalization in patients with ocular myasthenia gravis (OMG) treated with immunosuppression compared with patients without immunosuppression treatment.

METHODS

In this retrospective cohort study, we analyzed data from patients with OMG at seven medical centers in China from January 1, 2015 to May 1, 2019 and compared disease generalization in patients (treated with immunosuppression vs. not treated) within 2 years of disease onset using raw and inverse probability of treatment weighting (IPTW) analyses.

RESULTS

In the study population of 813 patients with OMG, 425 (52.3%) with immunosuppression had a mean (SD) onset age of 50.0 (15.1) years, and 188 (44.2%) were women. The remaining 388 (47.7%) patients were not immunosuppressed (mean age, 48.4 [15.0] years; 185 [47.7%] women). Disease generalization developed in 122 (31.4%) and 37 (8.7%) patients in the non-immunosuppression and immunosuppression groups, respectively. Relative to non-immunosuppression, immunosuppression was associated with a lower risk of generalization in a multivariable-adjusted Cox model (hazard ratio [HR], 0.27; 95% confidence interval [CI], 0.18-0.40; P<0.001) and IPTW-weighted Cox model (HR, 0.28; 95% CI, 0.19-0.42; P<0.001). In sensitivity analyses, longer duration of immunosuppression was associated with a lower risk of generalization (HR, 0.90 for every one-month increase; 95% CI, 0.87-0.92; P<0.001; IPTW-adjusted). Combination therapy with steroids and non-steroidal immunosuppressants showed superior efficacy in reducing the risk of generalization (HR, 0.14; 95% CI, 0.07-0.26; P<0.001).

CONCLUSIONS

Immunosuppression significantly reduced the 2-year risk of generalization in patients with OMG.

Thymectomy and Risk of Generalization in Patients with Ocular Myasthenia Gravis: A Multicenter Retrospective Cohort Study

This study aims to investigate the association between thymectomy and the risk of generalization in patients with ocular myasthenia gravis (MG). Data on patients with ocular MG from seven neurological centers in China were retrospectively reviewed. Ocular MG naïve to immunotherapy was categorized according to whether thymectomy was performed (thymectomized group vs. nonsurgical group). Patients in the thymectomized group all underwent surgery within 2 years since ocular symptom onset. The main outcome measure was the generalization. The follow-up period was defined from the date of ocular symptom onset to the date of generalization confirmation, immunotherapy initiation, or last follow-up (defined as 60 months). Of 519 eligible patients (mean [SD] age, 48.7 [15.2] years, 46.6% women), 31 (23.7%) of 131 generalized in the thymectomized group and 122 (31.4%) of 388 did in the nonsurgical group during a median follow-up of 19 months (IQR 8.0-50.0). Thymectomy was independently associated with reduced generalization risk (adjusted HR 0.41, 95% CI 0.25-0.66, P < 0.001). Multivariable stratified analysis also verified this association across the subgroups. Kaplan-Meier curves showed that the 5-year cumulative rate was significantly lower in the thymectomized group than in the nonsurgical group. To conclude, thymectomy may be considered effective in modifying the progression from ocular to generalized MG irrespective of thymoma.

Controversies in Ocular Myasthenia Gravis

Myasthenia gravis (MG) with symptoms limited to eye muscles [ocular MG (OMG)] is a rare disease. OMG incidence varies according to ethnicity and age of onset. In recent years, both an increase in incidence rate, particularly in the elderly, and a lower risk for secondary generalization may have contributed to the growing disease prevalence in Western countries. OMG should be considered in patients with painless ptosis and extrinsic ophthalmoparesis. Though asymmetric muscle involvement and symptom fluctuations are typical, in some cases, OMG can mimic isolated cranial nerve paresis, internuclear ophthalmoplegia, and conjugate gaze palsy. Diagnostic confirmation can be challenging in patients negative for anti-acetylcholine receptor and anti-muscle-specific tyrosine kinase antibodies on standard radioimmunoassay. Early treatment is aimed at relieving symptoms and at preventing disease progression to generalized MG. Despite the absence of high-level evidence, there is general agreement on the efficacy of steroids at low to moderate dosage; immunosuppressants are considered when steroid high maintenance doses are required. The role of thymectomy in non-thymoma patients is controversial. Prolonged exposure to immunosuppressive therapy has a negative impact on the health-related quality of life in a proportion of these patients. OMG is currently excluded from most of the treatments recently developed in generalized MG.

Prediction of generalization of ocular myasthenia gravis under immunosuppressive therapy in Northwest China

BACKGROUND

It is well demonstrated that immunosuppressants can reduce, but not eliminate the risk of generalized development in ocular myasthenia gravis (OMG). In this study, we aimed to explore the predictive factors of generalized conversion of OMG patients who received immunosuppressive treatments.

METHODS

OMG patients under immunosuppressive treatments in Tangdu Hospital from June 2008 to June 2012 were retrospectively reviewed. Baseline clinical characteristics were documented. Patients were followed up regularly by face-to-face interview and the main outcome measure was generalized conversion. The logistic regression analysis was performed to determine the predictive factors of generalization of OMG.

RESULTS

Two hundred twenty-three eligible OMG patients completed the final follow-up visit and 38 (17.0%) progressed to generalized MG (GMG) at a median time to generalization of 0.9 year. Patients with adult onset and positive repetitive nerve stimulation (RNS) of facial or axillary nerve had higher conversion rate than those with juvenile onset and negative RNS (p = 0.001; p = 0.019; p = 0.015, respectively). Adult-onset patients converted earlier than juvenile-onset OMG patients (p = 0.014). Upon multivariate logistic regression analysis, age of onset (Odds ratio [OR] 1.023, 95% confidence interval [CI] 1.006-1.041, p = 0.007) and positive facial nerve RNS (OR 2.826, 95%CI 1.045-5.460, p = 0.038) were found to be positively associated with generalized development. Moreover, an obviously negative association was found for disease duration (OR 0.603, 95%CI 0.365-0.850, p = 0.019).

CONCLUSIONS

Age of onset, disease duration and facial nerve RNS test can predict generalized conversion of OMG under immunosuppressive therapy. Adult-onset, shorter disease duration and facial nerve RNS-positive OMG patients have a higher risk of generalized development.

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.

Do early prednisolone and other immunosuppressant therapies prevent generalization in ocular myasthenia gravis in Western populations: a systematic review and meta-analysis

Background:

The majority of ocular myasthenia gravis (OMG) patients will progress to generalized myasthenia gravis (GMG), usually within 2 years of disease onset. The aim of this meta-analysis was to evaluate the effect of early prednisolone and other immunosuppressants therapy on the generalization rate in OMG patients.

Methods:

We searched the CENTRAL, EMBASE, and MEDLINE databases via the Ovid SP database for all relevant publications on 16 July 2018.

Results:

Eight studies comprising a total of 547 participants were included in our meta-analysis. Compared with pyridostigmine treatment, prednisolone and other immunosuppressants therapy produced an odds ratio (OR) for the development of GMG of 0.19 [95% confidence interval (CI), 0.11–0.30; I² = 37%], indicating that early prednisolone and other immunosuppressants therapy reduced the generalization rate in OMG by 81%.

Conclusions:

Early prednisolone and other immunosuppressants therapy can significantly reduce the risk of generalization in OMG patients, and should be considered in newly diagnosed OMG patients. Due to the inclusion of retrospective studies, this noted effect might have been related to corticosteroids, especially when immunosuppressants used at low dosages and in mild disease. Additionally, the data derived from Western populations, thus a prospective randomized controlled trial (RCT) is warranted to confirm this effect of early prednisolone and other immunosuppressants therapy on OMG generalization both in Western and Asian populations.

Incidence, Epidemiology, and Transformation of Ocular Myasthenia Gravis: A Population-Based Study

PURPOSE

To establish the incidence of ocular myasthenia gravis (OMG) as well as identify determinants of transformation to generalized myasthenia gravis (GMG) using a population-based record-linkage system.

DESIGN

Population-based, retrospective cohort study.

METHODS

All adults (≥18 years) diagnosed with myasthenia gravis (MG) from January 1, 1990, through December 31, 2017, were identified using the Rochester Epidemiology Project. Sixty-five patients with MG were identified. Data were collected regarding symptom onset, diagnostic testing results, and conversion from OMG to GMG.

RESULTS

Median follow-up time was 91 months (range 17-333 months). The annual incidence of MG was 2.20/100 000 with a mean age at diagnosis of 59 years (SD=17) and 62% male sex. Thirty-three (51%) of the 65 patients presented with OMG, providing an annual incidence of 1.13/100 000. Eighteen (55%) of the 33 patients presenting with OMG converted to GMG at a median time of 13 months (range 2-180 months). Sixteen (67%) of 24 OMG patients who were seropositive for acetylcholine receptor antibody (AchR Ab) converted to GMG at 5 years compared to 11% (1/9) of those who were seronegative (hazard ratio [HR], 8.2, P = .04). Ten (77%) of 13 OMG patients with a positive single-fiber electromyography (sfEMG) at diagnosis converted to GMG at 5 years, compared with 18% (2/11) of patients who had a negative sfEMG (HR, 5.5, P = .01).

CONCLUSIONS

In our population-based study, 51% (33/65) of patients with MG presented with isolated ocular involvement, with 55% (18/33) of these patients converting to GMG at some point in the course of their disease. Positive sfEMG and AchR Ab seropositivity at the time of diagnosis increased the risk of conversion to GMG.

Efficacy and Safety of Low-to-Moderate Dose Oral Corticosteroid Treatment in Ocular Myasthenia Gravis

PURPOSE

To evaluate the response to corticosteroid therapy as a primary treatment for ocular myasthenia gravis.

METHODS

Patients diagnosed as having ocular myasthenia gravis by an acetylcholine receptor binding antibody test between January 2011 and September 2015 were included in the study and started receiving treatment with a corticosteroid. Patients with a blowout fracture, hyperthyroidism, diabetes mellitus, hypertension, cardiovascular disease, or history of strabismus surgery were excluded. Disappearance of diplopia and ptosis were considered a response to treatment.

RESULTS

Methylprednisolone therapy was administered to 29 patients (19 men and 10 women; average age: 49 ± 16.5 years) as an initial treatment. A total of 6 patients were lost to follow-up. Twenty-three of 29 patients (82.6%) were regarded as having presented a response to treatment. The average treatment duration was 3 weeks for patients responding to primary treatment. Eight patients complained of adverse effects from steroid therapy such as heartburn, insomnia, weight gain, and myalgia.

CONCLUSIONS

A corticosteroid could be considered as an initial treatment for patients diagnosed as having ocular myasthenia gravis by an acetylcholine receptor binding antibody test. [J Pediatr Ophthalmol Strabismus. 2018;55(5):339-342.].

Generalization after ocular onset in myasthenia gravis: a case series in Germany

BACKGROUND AND PURPOSE

Approximately, 50% of myasthenia gravis (MG) patients initially present with purely ocular symptoms. Of these, about 60% will develop secondary generalized MG, typically within 2 years. Risk factors for secondary generalization are still controversial. In this study, we reviewed clinical parameters, thymic pathologies and medical treatments of MG patients with purely ocular symptoms at onset to investigate risk factors for secondary generalization.

METHODS

In this monocentric retrospective study, we reviewed consecutive patients who underwent robotic thymectomy between January 2003 and October 2017 in Charite Universitaetsmedizin Berlin. We used univariate and multivariate Cox proportional hazards regression models to identify factors associated with secondary generalization. Survival curves were plotted using Kaplan-Meier method and log-rank tests were performed to analyze the association between corticosteroids use and secondary generalization in subgroups defined by anti-AChR antibody status and thymic pathology.

RESULTS

One hundred and eighty of 572 MG patients who underwent robotic thymectomy were eligible for inclusion, of whom 110 (61.1%) developed a secondary generalized MG over a mean follow-up time of 23.6 months. The presence of a thymoma (HR 1.659, 95% CI (1.52-2.617), P = 0.029) was the only risk factor for secondary generalization in our series. Treating with corticosteroids was associated with a lower conversion rate in ocular myasthenia patients with thymic hyperplasia (n = 55, P = 0.028), but not with other thymic pathologies including thymoma and normal or atrophic thymus.

CONCLUSIONS

The conversion rate in ocular myasthenia was high in our series, predicted by the presence of a thymoma. Our findings suggest that corticosteroids can prevent secondary generalization in ocular myasthenia patients with thymic hyperplasia, which requires further research.

Antibody profile may predict outcome in ocular myasthenia gravis

An unsolved issue remains whether there are clinical and immunological features to predict in a single patient the risk of conversion from ocular Myasthenia Gravis (OMG) to generalized disease (GMG) as 50-60% of patients may progress within 1-2 years since onset. Anti-acetylcholine receptor antibodies (AChR Abs) are found in up to 50% of OMG patients; muscle-specific tyrosine kinase antibodies (MuSK-Abs) are present in about 70% of the whole seronegative (SN), who usually develop a severe disease with bulbar involvement. We surveyed a cohort of 175 OMG patients with purely ocular symptoms and we compare the outcome of patients with antibodies to AChR or to MuSK with those seronegative for both Abs (DSN). All patients had purely ocular signs for at least 24 months. Gender, age at onset, time to generalization or to worsening in quantitative ocular QMG scores, electrophysiological results were analyzed. Males were 58.9%, females 41.1%. Patients with late onset of symptoms after 50 years (LOMG) were 78.3%. We assayed anti-MuSK-Abs in 4.7%, anti-AChR Abs in 38.5%; 57.3% were defined DSN. Thirty-seven patients (21.1%) progressed to GMG during the observational time: 23 were females, 62% of the whole group of the generalized subjects, 75% of MuSK-positive OMG converted to GMG versus the 26.2% of AChR positive and 13.7% of DSN. Statistical analysis showed that gender and presence of antibodies either to AChR or to MuSK were independent predictors of worse outcome; the DSN subjects had lower risk of conversion to GMG.

Gender and quality of life in myasthenia gravis patients from the myasthenia gravis foundation of America registry

INTRODUCTION

Quality of life (QOL) has been poorly characterized among patients with myasthenia gravis (MG) other than assessments performed within the clinical setting.

METHODS

Patients age ≥ 18 years who were diagnosed with MG and registered with the MG patient registry between July 1, 2013, and June 30, 2016, were included. Demographic information, disease related history, and QOL were compared between men and women using multivariable analysis.

RESULTS

A total of 1,315 subjects (827 women) were included. Women were significantly younger, had a younger age at symptom onset, and were more likely to have thymoma and thymectomy. The 15-item Myasthenia Gravis Quality of Life scale (MG-QOL15) was significantly worse in women. MG-QOL15 score was comparable between women who had thymectomy and men with or without thymectomy.

DISCUSSION

QOL among MG patients is worse in women compared with men, but this disparity is eliminated in women who have undergone thymectomy. Muscle Nerve, 2018.

Ocular presentation of myasthenia gravis: A natural history cohort

INTRODUCTION

There are limited data on the natural history of untreated myasthenia gravis (MG) with ocular presentation.

METHODS

We analyzed 93 patients from symptom onset who presented to the Birmingham Midlands Eye Centre (BMEC) between January 2004 and July 2015. We used multiple stepwise logistic regression to identify predictive factors of generalization and Kaplan-Meier analysis on time to generalization.

RESULTS

Forty-six percent of patients developed generalized symptoms during the study period. Median time to generalization was 7 months. Time to generalization was earlier in patients seropositive for acetylcholine receptor (AChR) antibody (median 5 months vs. 21 months, P < 0.0001) and bilateral ptosis at onset (P = 0.015). Multivariate analysis identified AChR seropositivity [hazard ratio (HR) 5.03; 95% confidence interval (CI) 1.48-17.14; P = 0.001] and disease onset < 50 years (HR 3.58; 95% CI 1.18-10.90; P = 0.035) as risk factors for generalization.

DISCUSSION

As patients were steroid-naive before generalization, our cohort approximated the natural history of the condition. Muscle Nerve 57: 622-627, 2018.

Ptosis Surgery in Patients with Myasthenia Gravis: A Useful Adjunct to Medical Therapy

INTRODUCTION

Medical management can have limitations in improving ptosis in patients with myasthenia gravis (MG). We present our experience of ptosis surgery in MG.

MATERIALS AND METHODS

Clinical records of all patients with MG undergoing ptosis surgery from September 2007 to November 2013 in a single center were retrospectively reviewed. Change in upper marginal reflex distance (uMRD) was the main outcome measure.

RESULTS

Sixteen external levator advancement (ELA) procedures were performed on 11 MG patients. Fourteen of 16 procedures had pre- and postoperative uMRD documented. Thirteen of 14 procedures had improved lid height; mean increase in uMRD was 2.4 mm (P=0.0005651). Two patients required secondary lid elevation. Postoperative complications included more noticeable diplopia (n=1) and exposure keratopathy (n=1).

CONCLUSION

Ptosis surgery is a useful adjunct to medical therapy to improve lid height in MG patients with ptosis. Risks of diplopia and exposure keratopathy should be discussed with the patient pre-operatively.

Prognosis of Ocular Myasthenia Gravis: Retrospective Multicenter Analysis

PURPOSE

To calculate the rate and timing of conversion from ocular myasthenia gravis to generalized myasthenia gravis.

DESIGN

Retrospective multicenter analysis.

SUBJECTS

Patients included in the study were diagnosed with ocular myasthenia gravis without the presence of generalized disease at onset.

METHODS

We conducted a retrospective multicenter analysis. We reviewed charts of 158 patients who met diagnostic criteria for ocular myasthenia gravis. Patients were divided into 2 subgroups: an immunosuppressant treatment group and a nonimmunosuppressant treatment group. Timing of conversion to generalized disease and duration of follow-up also was evaluated. Additional data such as clinical symptoms at presentation, laboratory test results, and chest imaging results also were recorded.

MAIN OUTCOME MEASURES

Conversion rates to generalized myasthenia at 2 years, effect of immunosuppression on conversion, and timing of conversion.

RESULTS

The 158-patient cohort included 76 patients who received immunosuppressant therapy; the remaining 82 patients did not. The overall conversion rate to generalized disease was 20.9%. At 2 years, generalized myasthenia developed in 8 of 76 patients in the treated group and in 15 of 82 patients in the nonimmunotherapy group (odds ratio, 0.52; 95% confidence interval, 0.20-1.32). Median time for conversion to generalized disease was 20 months in the nonimmunosuppressant group and 24 months in the immunosuppressant group. Conversion occurred after 2 years of symptom onset in 30% of patients.

CONCLUSIONS

Conversion rates from ocular to generalized myasthenia gravis may be lower than previously reported both in immunosuppressed and nonimmunosuppressed patients. A subset of patients may continue to convert to generalized disease beyond 2 years from onset of symptoms, and close monitoring should be continued.

Quality of life in purely ocular myasthenia in Japan

Background

Since there has been no conclusive evidence regarding the treatment of ocular myasthenia, treatment guidelines were recently issued by the European Federation of Neurological Societies/European Neurological Society (EFNS/ENS). However, the therapeutic outcomes concerning the quality-of-life (QOL) of patients with ocular myasthenia are not yet fully understood.

Methods

We investigated the therapeutic outcomes of patients with purely ocular myasthenia in a multicenter cross-sectional survey in Japan. To evaluate the severity of ocular symptoms, we used the ocular-quantitative MG (QMG) score advocated by Myasthenia Gravis Foundation of America. We used the Japanese translated version of the MG-QOL15, a self-appraised scoring system.

Results

Of 607 myasthenia gravis (MG) patients with an observation-duration of illness ≥ 2 years, the cases of 123 patients (20%) were limited to ocular muscles (purely ocular myasthenia). During the entire clinical course, 81 patients experienced both ptosis and diplopia, 36 had ptosis alone, and six had diplopia alone. Acetyl-cholinesterase inhibitors and prednisolone were used in 98 and 52 patients, respectively. Treatment improved ocular symptoms, with the mean reduction in ocular-QMG score of 2.3 ± 1.8 points. However, 47 patients (38%) failed to gain minimal manifestation or a better status. Patients with unfavorable outcomes also self-reported severe QOL impairment. Multivariate analyses showed that the pretreatment ocular-QMG score was associated with unfavorable outcomes, but not associated with the patient’s QOL.

Conclusion

A treatment strategy designed in accord with a patient's ocular presentation must be considered in order to improve ocular symptoms and the patient's QOL.

"Why do I always see double?" A misdiagnosed case of ocular myasthenia gravis for 10 years

A 58-year-old man presented with diplopia and partial ptosis for 10 years. It was non-progressive in nature, despite inadequate medical attention the patient received from non-specialists/general practitioners. He did not have fatigability or diurnal variation in weakness and was clinically stable without exacerbations of disease for a decade. He did not have features of Graves's disease, oculopharyngeal dystrophy, cranial nerve paralysis, polymyositis and stroke. The possibility of an atypical presentation of myasthenia gravis (MG) was considered and the patient was evaluated. Ice pack test was negative, Cogan's lid twitch (CLT) test was positive and high titres of acetylcholine receptor antibodies (AChR Ab) suggestive of MG were found. He was treated accordingly with a very good response.

Prognostic factors and health-related quality of life in ocular Myasthenia Gravis (OMG)

We evaluate the factors predictive of prognosis in 91 Caucasian patients affected by ocular myasthenia gravis (OMG), followed at our Institution during an observational time, ranging from 12 to 240 months. The Myasthenia Gravis Foundation of America (MGFA) clinical classification was used to grade the disease severity. We considered as outcome measures the variation in two subscores, ocular (O-QMG) and nonocular (NO-QMG); the last one reflected bulbar, neck, extremity functions. None of the independent variables evaluated for association with the outcome, as age of onset, type of therapy, length of interval between first and last examinations, and presence of antibodies to acetylcholine receptors (AChR-Abs) significantly affected the evolution of O-QMG and of NO-QMG. Health-related quality of life (HRQol) was assessed in 63 patients. Variations of diplopia or ptosis did not affect significantly physical (PCS) or mental composite subscores (MCS) of the Short-Form Health Survey (SF-36). Human leukocyte antigen (HLA) genotyping was studied to explore whether HLA class I and II allelic distribution differed among MG patients and controls. None of the studied HLA alleles significantly differed between OMG patients and controls. Similarly, none of the alleles with frequencies higher than 15% either in OMG patients or in controls was significantly associated, after Bonferroni correction, with the presence or absence of anti-AChR-Abs in serum.