Myasthenia gravis and scleroderma: Two cases and a review of the literature

Gastrointestinal involvement in systemic sclerosis: pathogenesis, assessment and treatment

PURPOSE OF REVIEW

The majority of patients with systemic sclerosis (SSc) will experience involvement of their gastrointestinal over the course of their disease. Despite the high prevalence of gastrointestinal involvement in SSc, the strategies pertaining to the assessment and treatment for this clinical dimension of SSc have historically been limited. However, the present review highlights recent research contributions that enhance our understanding of SSc-GI patient subsets and provides updates on pathogenic mechanisms of disease, assessment and symptom-directed management.

RECENT FINDINGS

In the past few years, several studies have identified risk factors for more severe gastrointestinal disease in SSc and have provided insight to optimize diagnosis and management of SSc-GI symptoms. This article also provides a review of currently available investigations and therapies for individual SSc-GI disease manifestations and reflects on actively evolving areas of research, including our understanding the role of the gut microbiome in SSc.

SUMMARY

Here, we provide important updates pertaining to the risk stratification, assessment, diagnosis and management of SSc patients with gastrointestinal symptoms. These findings provide opportunities to enhance patient care and highlight exciting opportunities for future research.

Mixed connective tissue disease after thymectomy in refractory myasthenia gravis

Connective tissue diseases, including systemic lupus erythematosus (SLE) and systemic sclerosis are classic models of autoimmunity; diseases with large-scale loss of tolerance and subsequent development of pathogenic autoreactive lymphocytes and tissue targeting autoantibodies. Here we report a case of mixed connective tissue disease, with features of systemic lupus erythematosus and systemic sclerosis developing in a patient 10 years post thymectomy for myasthenia gravis. The patient developed acute cutaneous lupus, Raynaud's with digital ulcers, arthritis and lymphopenia. Her myasthenia continued to be resistant to treatment and her rheumatic disease progressed despite aggressive therapy. We performed a database search of MEDLINE, EMBASE, Scopus, and Web of Science for articles of similar cases post thymectomy from inception to August 2021, using the terms "systemic lupus erythematosus" (or systemic sclerosis, or connective tissue disease) and "myasthenia gravis" and "thymectomy". We identified 41 cases, 28 of SLE post thymectomy, 8 related to systemic sclerosis, 5 with mixed connective tissue disease and highlighted their different presentation and serology. We explore the role of the thymus, tolerance and myasthenia gravis in the development of connective tissue disease. This highlights the complexity of concurrent autoimmune diseases and their autoantibodies.

A practical approach to the evaluation and management of gastrointestinal symptoms in patients with systemic sclerosis

The gastrointestinal (GI) tract is the most commonly affected internal organ system in systemic sclerosis (SSc). SSc may lead to impaired function in any region of the GI tract, from the esophagus to the anorectum, which causes significant morbidity as well as mortality in patient subsets. Given the low prevalence of SSc in the community, many rheumatologists may not have a systematic framework for diagnosing or treating the GI complaints in this disease. These practice recommendations aim to summarize and consolidate the current guidelines from the fields of gastroenterology and rheumatology and establish a symptom-based framework for diagnosis and management based on available evidence in the literature. Subject areas that are in need of additional research are also identified.

Clinical Assessment of Gastrointestinal Involvement in Patients with Systemic Sclerosis

Systemic sclerosis (SSc) has the potential to affect any component of the gastrointestinal (GI) tract. GI involvement in SSc is a leading cause of morbidity and overall decreased quality of life in this patient population, identifying a need for a concise approach to work-up. This literature review aims to present a systematic, anatomical approach and differential diagnosis of GI involvement in SSc for the general internist and rheumatologist. Each component of the luminal GI tract has its own specified section, beginning with a review of a clinical approach to diagnosis that includes a differential for clinicians to consider, followed by a discussion of the literature surrounding objective evaluation of these conditions (i.e. serologic studies, imaging, endoscopy). Additionally there is a focused discussion on an approach to GI bleeding in the patient with SSc.

Thymectomy in patients with myasthenia gravis increases the risk of autoimmune rheumatic diseases: a nationwide cohort study

Objectives

Previous studies have shown myasthenia gravis (MG) and autoimmune rheumatic diseases (ARDs) share common pathogenetic mechanisms. Therefore, the present study investigated the possible relationship between MG and ARDs.

Methods

We analysed Taiwanese medical data from the Registry of Catastrophic Illness and identified patients with MG. From the entire general population data of the National Health Insurance Research Database, we randomly selected a comparison cohort that was frequency-matched by age (in 5-year increments), sex, and index date. We analysed the risk of ARDs by using a Cox proportional hazards regression model stratified by sex, age and treatment.

Results

In the present study, we enrolled 6478 patients with MG (58.03% women; mean age, 50.55 years) and 25 912 age- and sex-matched controls. The risk of total ARDs was 6.25 times higher in the MG cohort than in the non-MG cohort after adjustment for age and sex. Furthermore, the MG cohort was associated with a significantly higher risk of primary SS (pSS), SLE and other ARD types (adjusted hazard ratios: 15.84 [95% CI: 8.39, 23.91]; 11.32 [95% CI: 5.04, 25.429]; and 4.07 [95% CI: 1.31, 12.62], respectively). The MG cohort who underwent thymectomy had an increased risk of RA, pSS and SLE (adjusted hazard ratios: 4.41; 15.06; and 23.68, respectively).

Conclusion

The present nationwide cohort study revealed an association between MG and incident ARDs. The MG cohort who underwent thymectomy had an increased risk of RA, pSS and SLE. Future studies are needed to elucidate the underlying pathogenesis and to translate this into clinical therapeutic options.

The True Association of Systemic Sclerosis with Myasthenia Gravis and the Myth of D-Penicillamine-Induced Myasthenia

It has been long considered that d-penicillamine may induce various autoimmune conditions, including myasthenia gravis (MG), whereas early observations suggested that about 1.5% of patients with systemic sclerosis (SSc) develop MG. Along this line it has been thought that the association of SSc and MG was due to d-penicillamine, which was the standard therapy for SSc in the past. We report a 66-year-old woman with SSc who developed MG in the absence of d-penicillamine exposure. We found seven other similar cases in the literature, as well as seven additional cases in whom SSc followed MG. Since it has been clear now that different autoimmune diseases frequently cluster within families, we suggest a true association of these two autoimmune diseases which could be under-reported.

Spectrum of Muscle Histopathologic Findings in Forty-Two Scleroderma Patients With Weakness

OBJECTIVE

To determine if distinct muscle pathologic features exist in scleroderma subjects with weakness.

METHODS

This retrospective study included weak scleroderma subjects with muscle biopsies available for review. Biopsies were systematically assessed for individual pathologic features, including inflammation, necrosis, fibrosis, and acute neurogenic atrophy. Based on the aggregate individual features, biopsies were assigned a histopathologic category of polymyositis, dermatomyositis, necrotizing myopathy, nonspecific myositis, "acute denervation," "fibrosis only," or "other." Clinical data analyzed included autoantibody profiles, scleroderma subtype and disease duration, Medsger muscle severity scores, creatine kinase, electromyography, and muscle magnetic resonance imaging.

RESULTS

A total of 42 subjects (79% female and 64% diffuse scleroderma) were included in this study. Necrosis (67%), inflammation (48%), acute neurogenic atrophy (48%), and fibrosis (33%) were the most prevalent pathologic features. The presence of fibrosis was strongly associated with anti-PM-Scl antibodies. Histopathologic categories included nonspecific myositis (36%), necrotizing myopathy (21%), dermatomyositis (7%), "acute denervation" (7%), "fibrosis only" (7%), and polymyositis (5%). Disease duration of scleroderma at the time of muscle biopsy was shorter in polymyositis than other histopathologic categories. Patients with anti-PM-Scl and Scl-70 antibodies also had a shorter disease duration than those with other autoantibody profiles.

CONCLUSION

Nonspecific myositis and necrotizing myopathy were the most common histopathologic categories in weak scleroderma subjects. Surprisingly, nearly half of the subjects studied had histologic evidence of acute motor denervation (acute neurogenic atrophy); this has not been previously reported. Taken together, these observations suggest that a variety of pathologic mechanisms may underlie the development of myopathy in scleroderma.

The course of myasthenia gravis with systemic lupus erythematosus

BACKGROUND

Systemic lupus erythematosus (SLE) is one of the autoimmune diseases, which is rarely reported with Myasthenia Gravis (MG). In the literature, the clinical features of MG in these patients were not mentioned in detail. Here, we want to present our five patients with MG and SLE.

METHODS

Between 2000 and 2010, 132 MG patients were evaluated and have been followed up in our institution. Five patients had MG with SLE and eleven patients had antinuclear antibody (ANA) positivity without SLE symptoms. The clinical, laboratory findings and treatment responses were reviewed.

RESULTS

All patients had generalized MG and four of five patients experienced at least one myasthenic crisis. The response to corticosteroid was poor; consequently, they needed immunosuppressive treatments, IVIg or plasmapheresis. Although in the literature thymectomy was accused of the precipitation of SLE, in our series SLE symptoms preceded thymectomy.

CONCLUSION

We would like to point out that MG and SLE being two autoimmune diseases may coexist. This coexistence might cause a more severe myasthenic course compared to MG alone; therefore, these patients need a close and frequent follow-up.

Acute presentation of autoimmune hepatitis in a patient with myasthenia gravis, thymoma, Hashimoto thyroiditis and connective tissue disorder

Myasthenia gravis is an antibody-mediated autoimmune disease at the neuromuscular junctions. It can be associated with many other autoimmune diseases. We report a case of acute presentation of autoimmune hepatitis with myasthenia gravis, thymoma, Hashimoto thyroiditis and connective tissue disorder.

Successful low-dose azathioprine for myasthenia gravis despite hepatopathy from primary sclerosing cholangitis: a case report

INTRODUCTION

Although myasthenia gravis is frequently associated with other disorders, it has not been reported together with primary sclerosing cholangitis, complicating the administration of liver-toxic immunosuppressive therapy.

CASE PRESENTATION

A 73-year-old Caucasian woman with a history of arterial hypertension, thyroid dysfunction, glaucoma, right-sided ptosis and later generalized weakness, was diagnosed with myasthenia gravis. Additionally, primary sclerosing cholangitis was detected, initially prohibiting the administration of immunosuppressants. Despite treatment with steroids and pyridostigmine she repeatedly experienced myasthenic crises. After the fifth crisis and after antibody titers had reached levels > 100 nmol/L during two years of follow-up, it was decided to restart azathioprine. Interestingly, low-dose azathioprine (1.5 mg/kg/day) was well tolerated, had a positive clinical and immunological effect and did not worsen primary sclerosing cholangitis.

CONCLUSION

Myasthenia gravis may occur together with primary sclerosing cholangitis in the same patient. Mild immunosuppression with azathioprine is feasible and effective in such a patient, without worsening myasthenia gravis or primary sclerosing cholangitis.