Dysphagia in elderly men with myasthenia gravis

Predominant Intractable Nausea in the Diagnosis of Bulbar Myasthenia Gravis: A Case Study and Review of Literature

Gastrointestinal (GI)-predominant myasthenia gravis (MG) is rare and presents a complex clinical scenario. We report the case of a 73-year-old female with dysphagia and intractable nausea found to have bulbar MG. Her symptoms persisted despite conventional MG management with plasma exchange therapy and anticholinergics. We review existing literature and discuss the clinical manifestations, diagnosis, and treatment of bulbar MG. This case highlights the need for novel MG treatment modalities in patients like ours with anomalous, GI-predominant MG who might not respond to conventional management.

Comprehensive evaluation of velopharyngeal function in myasthenia gravis patients

PURPOSE

Hypernasality, which is a symptom of dysarthria, may be seen in patients with Myasthenia Gravis with bulbar symptoms. However, there is not enough evidence to show that these patients may have velopharyngeal dysfunction. This study investigates the features of velopharyngeal function in myasthenia gravis patients using objective and subjective measurement tools.

METHODS

Ten adult myasthenia gravis patients with bulbar symptoms and ten adult myasthenia gravis patients without bulbar symptoms were recruited for this study. Ten healthy subjects were also included as the control group. The nasalance scores of the participants were determined using a nasometer. The degree and pattern of velopharyngeal closure were scored using flexible nasoendoscopy during speech, blowing, dry swallowing, and food swallowing. Perceptual hypernasality was assessed.

RESULTS

Velopharyngeal dysfunction was detected in 50% of the myasthenia gravis patients with bulbar symptoms. Velopharyngeal dysfunction was not seen in myasthenia gravis patients without bulbar symptoms. The degree of velopharyngeal closure in patients with bulbar symptoms differed depending on the tasks being performed. No significant difference in velopharyngeal closure patterns was observed between the groups (p < 0.05).

CONCLUSION

Myasthenia gravis patients with bulbar involvement may have velopharyngeal dysfunction. It is important to conduct a comprehensive evaluation to assess all aspects of the velopharyngeal function.

Swallowing dysfunction in myasthenia gravis patients examined with high-resolution manometry

OBJECTIVE

To prospectively compare oropharyngeal swallowing dysfunction in myasthenia gravis (MG) patients presenting with difficulty in swallowing between the neutral and chin-down positions, based on the results of high-resolution manometry (HRM) examination.

METHODS

We prospectively compared the HRM results of swallowing studies of seven MG patients showing difficulty in swallowing (neutral and chin-down positions) at the Department of Neurology of our institution during the period February-December 2018. The HRM assessment parameters were as follows: maximum swallowing pressure (SP) at the soft palate, meso‑hypopharynx, and upper esophageal sphincter (UES), and the duration of relaxation pressure at the UES. These parameters were compared between the two positions and their correlations with the results of neurological evaluations, such as the Quantitative Myasthenia Gravis (QMG) score (total and neck muscles alone), and grip strength, were also analyzed.

RESULTS

In comparison with the neutral position, in the chin-down position the maximum SP at the meso‑hypopharynx was significantly increased (p < 0.05), the maximum SP at the UES was significantly decreased (p < 0.05), and the duration of relaxing SP at the UES was significantly increased (p < 0.05). Interestingly, there were no correlations between the SP at any location and the results of the neurological evaluations.

CONCLUSIONS

The chin-down position appears useful for improving pharyngeal clearance in MG patients, by promoting increased SP at the meso‑hypopharynx, relaxing SP at the UES, and increasing the duration of relaxation pressure at the UES.

Relationship between Dysarthria and Oral-Oropharyngeal Dysphagia: The present evidence

There is a high prevalence of dysphagia in patients with neuromuscular diseases and stroke, and consequences can be profound. However, the correlation of dysarthria and oral-oropharyngeal dysphagia remains unclear. This review aimed to define the clinical co-presentation of dysarthria and dysphagia in this population. A PubMed search to identify literature on the prevalence of dysarthria and dysphagia was systematically conducted in the English language literature since 1995. Subjective and objective outcomes instruments were identified for both dysarthria and dysphagia. Studies that included prevalence and co-presentation were included. Inclusion and exclusion criteria were applied according to the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA). Of the 1,056 articles identified in the search, 20 articles met the search criteria. An additional 4 articles were examined for a total of 24 articles for analysis. Dysarthria and dysphagia were found to be highly prevalent among patients with neuromuscular disease (NMD). Overall, there was a higher prevalence of dysarthria than dysphagia. Of those patients with dysphagia, some reports estimate 76-90% of patients with NMD also had dysarthria. Dysarthria is a strong clinical clue to the presence of dysphagia. Existing subjective questionnaires may not reveal the presence of oropharyngeal dysphagia, but objective measures are more revealing. Further study to correlate the degree of dysarthria and severity of oral-oropharyngeal dysphagia are warranted.

Misdiagnosis of myasthenia gravis presenting with tongue and palatal weakness

We discuss the case of an elderly male who presented with a history of dysphagia, dysphonia, palatal weakness and a sensation of tongue swelling, each symptom of varying time duration. Myasthenia gravis may have a variety of presentations that include ocular fatigability, respiratory muscle weakness and bulbar symptoms. The variety of these myasthenic syndromes can serve as a barrier to diagnosis and can often result in delayed or incorrect diagnosis. In this report, we present an atypical presentation of a relatively rare condition.

Oropharyngeal dysphagia

Although the aging process per se can produce measurable changes in the normal oropharyngeal swallow, these changes alone are rarely sufficient to cause clinically apparent dysphagia. The causes of oropharyngeal dysphagia in the elderly are predominantly neuromyogenic, with the most common cause being stroke. The evaluation of oropharyngeal dysphagia in the elderly involves early exclusion of structural abnormalities, detection of aspiration by videofluoroscopy which might dictate early introduction of nonoral feeding, and exclusion of underlying systemic and neuromyogenic causes that have specific therapies in their own right. Such conditions include Parkinson disease, myositis, myasthenia, and thyrotoxicosis. Management is best delivered by a multidisciplinary team involving physician, speech pathologist, nutritionist and, at times, a surgeon.

Fiberoptic endoscopic evaluation of swallowing with simultaneous Tensilon application in diagnosis and therapy of myasthenia gravis

BACKGROUND

Dysphagia is a common symptom in myasthenia gravis (MG). Clinical examination alone fails to detect and grade myasthenic dysphagia sufficiently. For a more precise examination of swallowing function in myasthenia gravis additional technical tools are necessary.

OBJECTIVE

To investigate the diagnostic and therapeutic impact of fiberoptic endoscopic evaluation of swallowing with simultaneous Tensilon application (FEES-Tensilon Test) in myasthenia gravis.

METHODS

FEES-Tensilon Test was performed following a standardized protocol. Four severely affected patients with dysphagia as their leading symptom were examined. Dysphagia was characterized by five salient endoscopic findings: leakage, delayed swallowing reflex, penetration, aspiration and residues. If a normalisation or at least an improvement of swallowing function occurred shortly after Tensilon administration the FEES-Tensilon Test was rated as being positive.

RESULTS

In three patients the FEES-Tensilon Test successfully detected MG-related dysphagia. In one patient with dysphagia caused by oculopharyngeal muscular dystrophy the FEES-Tensilon Test was truly negative. Beside an early diagnosis of MG-related dysphagia, the FEES-Tensilon Test was useful in the differentiation between myasthenic and cholinergic crisis and in guiding treatment decisions. In all patients the FEES-Tensilon Test was superior to clinical evaluation of dysphagia. No severe side effect occurred while performing the FEES-Tensilon Test.

CONCLUSION

The FEES-Tensilon Test is a suitable tool in the diagnosis and therapy of myasthenia gravis with pharyngeal muscles weakness.

Myasthenia gravis--a rare presentation with tongue atrophy and fasciculation

We report the case of an unusual presentation of myasthenia gravis with tongue atrophy and fasciculation. Myasthenia gravis is an autoimmune condition associated with weakness and fatigability of voluntary muscles. In >50%, the initial symptoms and signs are related to extraocular muscle weakness, such as diplopia or ptosis [Tsung K, Seggev JS. An unusual cause of dysphagia. West J Med 1995; 163: 159-60]. Rarely, it is known to affect bulbar muscles and can lead to dysphagia and respiratory compromise.

Silent Aspiration: What Do We Know?

Although clinically evident aspiration is common in subjects with dysphagia, a significant proportion may aspirate silently, i.e., without any outward signs of swallowing difficulty. This article reviews the literature on the prevalence, etiology, and prognostic significance of silent aspiration. An electronic database search was performed using silent aspiration, aspiration, dysphagia, and stroke as search terms, together with hand-searching of articles. Silent aspiration has been described in many conditions and subgroups of patients (including normal individuals), using a number of detection methods, making comparisons a challenge. The best data are for acute stroke, in which 2%-25% of patients may aspirate silently. Mechanisms associated with silent aspiration may include central or local weakness/incoordination of the pharyngeal musculature, reduced laryngopharyngeal sensation, impaired ability to produce a reflexive cough, and low substance P or dopamine levels. In terms of prognosis, silent aspiration has been associated with increased morbidity and mortality in many but not all studies. However, some degree of silent aspiration at night may be normal in healthy individuals. The phenomenon of silent aspiration is poorly understood and further research is needed to improve methods of detection and thereby better define its prevalence and prognostic significance.

Myasthénie du sujet âgé : analyse rétrospective de 23 observations

PURPOSE

There is evidence that myasthenia gravis is substantially underdiagnosed in older people, for which diagnosis and treatment may be difficult.

METHOD

We report on a series of 23 cases of myasthenia gravis diagnosed after the age of 65. Diagnosis was ascertained by compatible symptoms, associated with electrophysiological evidence and/or presence of antibodies to the acetylcholine receptor (AchRAb) and/or positive prostigmine test.

RESULTS

Twelve female and 11 male patients were identified, with a mean age of 77 (range: 66-89). Initial symptoms were ocular in 8 cases (35%), bulbar and ocular in 9 cases (39%), generalized in 6 cases (26%). Diagnosis was delayed in many patients (mean delay 31+/-47 months). Prostigmine test was positive in 16 cases (100%), AchRAb were positive in 19/23 cases (83%). Only one thymoma was found. Other diagnoses than myasthenia gravis, mainly stroke, were often considered. Treatment with anticholinesterase drugs, prescribed in all cases, has been able to control symptoms in only 3 cases. Corticosteroids were used in 10 cases, azathioprine or mycophenolate mofetil in 14 cases, intravenous immunoglobulins in 8 cases, and plasma exchanges in 2 cases. Thymectomy was performed on one patient with thymoma. Three patients were hospitalized in intensive care units for several weeks, and 3 patients died from their myasthenia.

CONCLUSION

Diagnosis of myasthenia gravis is often missed or delayed in the elderly, because of a broad differential diagnosis in older people, and because the high incidence of the disease in middle and old age is often overlooked. The outcome of myasthenia gravis in older people is far from simple, and immunomodulation proves to be necessary in most cases. However, quality of life of surviving patients appears good.

Dysphagia in aging

Dysphagia is a common problem in older patients and is becoming a larger health care problem as the populations of the United States and other developed countries rapidly age. Changes in physiology with aging are seen in the upper esophageal sphincter and pharyngeal region in both symptomatic and asymptomatic older individuals. Age related changes in the esophageal body and lower esophageal sphincter are more difficult to identify, while esophageal sensation certainly is blunted with age. Stroke, Parkinson's disease, amyotrophic lateral sclerosis, Zenker's diverticula, and several other motility and structural disorders may cause oropharyngeal dysphagia in an older patient. Esophageal dysphagia can also be caused by both disorders of motility (achalasia, diffuse esophageal spasm, scleroderma and others) and structure (malignancy, strictures, rings, external compression, and others). Many of these disorders have an increased prevalence in older patients and should be sought with an appropriate diagnostic evaluation in older patients. The treatment of dysphagia in older patients is similar to that in younger patients, but more invasive therapies such as surgery may not be possible in some older patients making less aggressive medical and endoscopic therapy more attractive.

Videofluoroscopic assessment of swallowing function in patients with myasthenia gravis

Swallowing function in myasthenia gravis (MG) was investigated by videofluoroscopy (VF). A total of 23 VF examinations were performed on 11 MG patients at various time points over the exacerbation and remission stages of disease. The assessment parameters on VF examination are set as follows: bolus transport from the mouth to the pharynx, bolus holding in the oral cavity, velopharyngeal seal, tongue base movement, pharyngeal constriction, laryngeal elevation, upper esophageal sphincter (UES) opening, and bolus stasis at the pyriform sinus (PS). Aspiration was also assessed on VF examination. Aspiration was seen in 34.8%, and half of these cases involved silent aspiration. Three of four cases that showed silent aspiration went on to experience aspiration pneumonia during the follow-up term. By Spearman's rank correlation, disturbance of laryngeal elevation was significantly correlated with aspiration (p=0.001), and incomplete UES opening was not significantly, but tended to be, correlated with aspiration (p=0.067). Although other parameters in the oral and pharyngeal phase on VF examination, such as bolus transport from the oral cavity to the pharynx, pharyngeal constriction, or stasis at the PS, were remarkably disturbed (in more than 50% of the examinations), those parameters were not good indicators for aspiration. When a disturbance of laryngeal elevation is found at a bedside clinical test, we recommend performing precise swallowing evaluation, such as VF, Fiberoptic Endoscopic Evaluation of Swallowing (FEES), and/or scintigraphic assessment of swallowing, for MG patients, to detect silent aspiration.

Prediction of aspiration in myasthenia gravis

Prediction of the risk of dysphagia and aspiration is important in the management of myasthenia gravis (MG). We assessed the ability of four bedside clinical tools to predict aspiration in 20 MG patients. Patients completed a self-directed questionnaire, underwent clinical neurological assessment and a bedside speech pathology assessment, and were assessed with the quantitative myasthenia gravis (QMG) score. The ability of these tools to predict aspiration was compared with the results of a modified barium swallow. Seven patients aspirated, 4 silently. The total self-directed questionnaire score, two specific questions on the self-directed questionnaire, the prediction based on clinical neurological assessment, and the QMG bulbar subset score all correlated with aspiration. The speech pathology prediction was highly sensitive but less specific. This pilot study shows that simple clinical tools can predict which MG patients are at risk of aspiration.

Treatment of Oropharyngeal Dysphagia

Substantial ignorance and controversy surround the management of neuromyogenic pharyngeal dysphagia. The major obstacle to confident recommendations is the lack of high-level evidence supporting most available therapies. There is reasonable evidence supporting cricopharyngeal disruption (myotomy or dilatation) in primary restrictive disorders of this region, but low-level evidence supporting myotomy in pure neuromyogenic dysphagia. There is reasonable evidence supporting current dietary recommendations as aspiration-minimization strategies. There is only low-level evidence, albeit consistent, to support swallow-behavior modification therapies. The type of therapy needs to be tailored to the individual and depends upon many variables, including cognitive ability, severity and mechanics of pharyngeal dysfunction, and the perceived safety of continued oral feeding. One or more of these strategies are recommended where appropriate because where the level of evidence is low, it is at least consistently favorable and such therapies have not been proven to be ineffective.

Evidence of underdiagnosis of myasthenia gravis in older people

BACKGROUND

Myasthenia gravis is a potentially serious but treatable muscle disease caused by autoantibodies directed at the acetylcholine receptor (AChR) on the postsynaptic membrane of the neuromuscular junction. There is anecdotal evidence that the diagnosis is sometimes missed in older patients.

OBJECTIVE

To examine the incidence and age distribution of positive AChR antibodies in samples referred to diagnostic laboratories in the UK, and the prevalence of positive AChR antibodies in samples from a cohort of older individuals.

METHODS

Positive AChR antibody tests were identified from all UK centres registered for the assay with the European quality assurance scheme (EQAS) during 1997-99, and the age and sex specific incidence was calculated, based on the UK population. The prevalence of AChR antibodies in sera from a sample of 2000 individuals aged > or =60 years was determined.

RESULTS

3183 individuals had positive AChR antibody tests on routine screening during the years 1997 to 1999 in the UK, giving an annual incidence of 1.8/100 000. In both sexes, the age specific incidence rose steeply between the ages of 45 and 74, reaching 9.9/100 000 in men, and then fell, with a sharp decline above the age of 80. In the prevalence study, whereas only one serum from individuals aged 60-74 years was positive for AChR antibodies (0.12%), sera from eight individuals aged > or =75 years were positive (0.7%). Only one had a previous clinical diagnosis of myasthenia gravis but four others had histories of stroke or transient ischaemic attacks.

CONCLUSIONS

The sharp fall in the incidence of clinically recognised myasthenia gravis in people over 80 years of age in our national AChR antibody incidence study, and the high prevalence of previously unrecognised positive AChR antibodies in those > or =75 years old, suggest that myasthenia gravis may be substantially underdiagnosed in older people.

Dysphagia: evaluation and treatment

The evaluation of dysphagia begins with a careful history, which usually points to the underlying cause in up to 80% of cases. The goals of the history are to distinguish oropharyngeal causes from esophageal causes of dysphagia and to distinguish mechanical from motor disorders of the esophagus in those patients with esophageal dysphagia. Evaluation typically begins with a videofluoroscopic examination in patients with oropharyngeal dysphagia and begins with a routine barium swallow or upper GI endoscopy in patients with esophageal dysphagia. Esophageal manometry may be an adjunct to the evaluation of patients with esophageal dysphagia, particularly to confirm specific motor disorders, such as achalasia. The management of functional causes of dysphagia is supportive and empiric given the lack of well-controlled treatment studies in this heterogenous group of patients.

Neuromuscular diseases and disorders of the alimentary system

This review outlines the relationship and interaction between neuromuscular diseases and disorders of the alimentary system. Neuromuscular manifestations of gastrointestinal and hepatobiliary diseases are first considered. Such diseases may cause neuromuscular disorders by leading to nutritional deficiency or by more direct mechanisms. The pathogenesis, clinical features, and treatment of these various neuromuscular manifestations are discussed. The impact of disorders of nerve, neuromuscular transmission, and muscle on the alimentary system is then reviewed. The main sequelae are impaired deglutition and gastrointestinal dysmotility. The management of these complications is considered.

Controlled study of EMG activity of the jaw closers and openers during mastication in patients with myasthenia gravis

Mastication was evaluated in patients with bulbar myasthenia gravis and compared with that of patients with ocular myasthenia gravis, patients in remission who previously suffered from bulbar symptoms, and healthy controls. Bulbar myasthenia gravis may impair mastication due to weakness of the masticatory muscles. The aim of the study was to objectively evaluate the influence of myasthenia gravis on mastication. The subjects chewed a piece of breakfast cake and chewed 1 min on a piece of chewing gum. Surface EMG of the masseter muscle, temporalis muscle and jaw opener muscles was recorded. Statistical analysis revealed that bulbar patients produced significantly less EMG activity in the closing phase of a chewing cycle in both experiments. The EMG of the masseter muscle expressed as percentage of the maximum EMG during maximal clenching showed significantly higher values in the bulbar group than in the other groups. This was not found for the temporalis muscle. It was suggested that bulbar patients use a strategy of limited effort to produce a bolus that can be swallowed. The ocular patients and the patients in remission showed no subclinical impairments in muscle function during chewing.

Clinical and electrophysiological evaluation of dysphagia in myasthenia gravis

OBJECTIVE

To evaluate dysphagia at the oropharyngeal stage of swallowing and to determine the pathophysiological mechanisms of dysphagia in patients with myasthenia gravis.

METHODS

Fifteen patients with myasthenia gravis with dysphagia and 10 patients without dysphagia were investigated by a combined electrophysiological and mechanical method described previously. Laryngeal movements were detected by a piezoelectric transducer and the related submental EMG (SM-EMG) and sometimes the EMG of cricopharyngeal muscle of the upper esophageal sphincter (CP-EMG) were recorded during dry or wet swallowing. The results of these electrophysiological variables were compared with those of normal age matched control subjects.

RESULTS

In patients with myasthenia gravis with dysphagia, it was found that the time necessary for the larynx to remain in its superior position during swallowing and swallowing variability in successive swallows increased significantly compared with normal subjects and with patients with myasthenia gravis without dysphagia. The total duration of SM-EMG activity was also prolonged in both groups but more severely in the dysphagic patients. Electromyographic activity of the CP sphincter was found to be normal in the dysphagic patients investigated. All the patients with myasthenia gravis with dysphagia had pathological dysphagia limits (<20 ml water) whereas other patients except two, were within normal limits.

CONCLUSIONS

Because the electrophysiological variables related to oropharyngeal swallowing were prolonged even in patients with myasthenia gravis without dysphagia, it is concluded that the submental and laryngeal elevators are involved subclinically in myasthenia gravis and, because of compensating mechanisms, the patient may not be dysphagic. As the CP-EMG behaviour was found to be normal, a coordination disorder between normal CP sphincter muscle and the affected striated muscles of the laryngeal elevators may be one of the reasons for dysphagia in myasthenia gravis. This method also made it possible to investigate the myasthenic involvement in the laryngeal elevators that cannot be evaluated by other electrophysiological methods in myasthenia gravis.

Dysphagia caused by neurologic deficits

This article provides a brief review of the neurophysiology behind the normal swallow. The examination and work-up of a patient with dysphagia is then detailed. Finally, the major neurologic conditions associated with dysphagia are considered.