Paraneoplastic Dermatomyositis Syndrome Presenting as Dysphagia

Proximal muscle weakness as the sole manifestation of Cushing's disease, misdiagnosed as dermatomyositis: a case report

BACKGROUND

Cushing's syndrome consists of signs and symptoms related to prolonged exposure to high levels of glucocorticoid, and should be considered in individuals with the discriminatory signs and symptoms. Proximal myopathy is an important discriminatory sign.

CASE PRESENTATION

We report the case of a 36-year-old Iranian man who presented with proximal muscle weakness. He visited a rheumatologist in an outpatient clinic, and according to proximal muscle weakness and heliotrope rash (based on the rheumatologist's notes) with the impression of dermatomyositis, prednisolone and azathioprine were prescribed for him that did not improve his clinical status and he was gradually wheelchair dependent. He was admitted to the hospital for evaluation of paraneoplastic syndromes. Standard laboratory tests and imaging were unremarkable, other than a brain magnetic resonance imaging that demonstrated a 30 × 12 mm homogeneously enhancing mass in the sellar region with extension to the suprasellar area. He had serum cortisol of 295 ng/mL, and adrenocorticotropic hormone of 222 pg/mL (on 5 mg prednisolone twice daily), with a diagnosis of Cushing's disease. He underwent two sessions of trans-sphenoidal surgery 4 months apart. After the first surgery, the proximal muscle weakness improved dramatically and he was walking with the aid of a walker, and after the second surgery he is walking without any aids.

CONCLUSION

This case report emphasizes the high diagnostic importance of proximal muscle weakness as the sole presenting manifestation of Cushing's syndrome/disease.

The Impact of Dysphagia in Myositis: A Systematic Review and Meta-Analysis

(1) Background: Dysphagia is a clinical hallmark and part of the current American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) diagnostic criteria for idiopathic inflammatory myopathy (IIM). However, the data on dysphagia in IIM are heterogenous and partly conflicting. The aim of this study was to conduct a systematic review on epidemiology, pathophysiology, outcome and therapy and a meta-analysis on the prevalence of dysphagia in IIM. (2) Methods: Medline was systematically searched for all relevant articles. A random effect model was chosen to estimate the pooled prevalence of dysphagia in the overall cohort of patients with IIM and in different subgroups. (3) Results: 234 studies were included in the review and 116 (10,382 subjects) in the meta-analysis. Dysphagia can occur as initial or sole symptom. The overall pooled prevalence estimate in IIM was 36% and with 56% particularly high in inclusion body myositis. The prevalence estimate was significantly higher in patients with cancer-associated myositis and with NXP2 autoantibodies. Dysphagia is caused by inflammatory involvement of the swallowing muscles, which can lead to reduced pharyngeal contractility, cricopharyngeal dysfunction, reduced laryngeal elevation and hypomotility of the esophagus. Swallowing disorders not only impair the quality of life but can lead to serious complications such as aspiration pneumonia, thus increasing mortality. Beneficial treatment approaches reported include immunomodulatory therapy, the treatment of associated malignant diseases or interventional procedures targeting the cricopharyngeal muscle such as myotomy, dilatation or botulinum toxin injections. (4) Conclusion: Dysphagia should be included as a therapeutic target, especially in the outlined high-risk groups.

Paraneoplastic dermatomyositis appearing after nivolumab therapy for gastric cancer: a case report

BACKGROUND

While dermatomyositis is often associated with malignancy, several autoimmune diseases like myositis can be caused by immune checkpoint inhibitors. Differentially diagnosing malignancy-associated dermatomyositis or myositis caused by immune checkpoint inhibitors is sometimes difficult, particularly when a patient with malignancy shows the symptoms of myositis after checkpoint inhibitor administration. We experienced such a case in which we had difficulties in diagnosing paraneoplastic dermatomyositis or drug-associated myositis. In this case, all of our team initially assumed that the diagnosis was myositis caused by immune checkpoint inhibitors. However, it turned out finally that the diagnosis was paraneoplastic dermatomyositis. Because the diagnosis was unexpected, we report here.

CASE PRESENTATION

We report the case of a 71-year-old Japanese man who developed clinical symptoms of myositis, such as muscle aches and weakness, after initiation of nivolumab therapy for his gastric cancer. He was initially diagnosed with nivolumab-induced myositis, because the myositis symptoms appeared after nivolumab administration, and nivolumab is known to trigger various drug-associated autoimmune diseases. However, according to his characteristic skin lesions, the type of muscle weakness, his serum marker profiles, electromyography of his deltoid muscle, and magnetic resonance imaging, he was finally diagnosed as having paraneoplastic dermatomyositis. Accordingly, treatment with intravenously administered corticosteroid pulse treatment, immunoglobulin injection, and tacrolimus was applied; his symptoms subsequently improved. However, to our regret, at day 142 after administration, he died due to rapid worsening of his gastric cancer.

CONCLUSION

Differentially diagnosing paraneoplastic dermatomyositis or drug-associated myositis caused by immune checkpoint inhibitors is difficult in some cases. The differential diagnosis is crucial because it influences the decision regarding the appropriateness of the use of immunosuppressive treatment against the autoimmune diseases as well as the decision regarding the appropriateness of the continuous use of immune checkpoint inhibitors against the primary cancers. Because subclinical autoimmune disease may become overt after administering immune checkpoint inhibitors, non-apparent autoimmune diseases, which have already existed, should also be considered to avoid the delay of appropriate treatment, when symptoms of autoimmune diseases are recognized.