Imaging swallowing function and the mechanisms driving dysphagia in inclusion body myositis

Sporadic inclusion body myositis (IBM) is a progressive condition which commonly affects patients aged above 40. IBM does not respond to immunosuppression and no proven treatments are available. Up to 80% of patients develop some degree of swallowing impairment during the disease course. Dysphagia is a source of marked morbidity in IBM and predisposes patients to life-threatening complications such as aspiration pneumonia. The pathophysiology behind dysphagia in IBM is not fully understood. Evidence from imaging demonstrates that impaired swallowing is predominantly underpinned by oropharyngeal deficits. Changes in cricopharyngeal physiology is thought to be an important factor influencing dysphagia in IBM. However, it is unclear whether this is secondary to structural changes within the cricopharyngeus itself or driven by impairment of the muscles promoting pharyngeal clearance. The approach to dysphagia in IBM patients is limited by a lack of validated instruments to reliably assess swallowing function and an absence of effective therapeutic interventions derived from controlled trials targeting dysphagia. Imaging modalities such as the video fluoroscopic swallowing study (VFSS) are commonly used to evaluate dysphagia in IBM. Whilst VFSS is a commonly used technique in clinical practice; cumulative radiation exposure with repeated testing can be a limitation. Alternative imaging techniques could be developed further as outcome measures for assessing swallowing.In this review, we provide an overview of imaging techniques used to assess swallowing and the insight provided from such investigations into the mechanisms behind dysphagia in IBM. We suggest future directions for evaluation and outcome measurement of dysphagia in this population.

Myasthenia gravis with inclusion body myositis: A case report

We present the case of a 75-year-old man diagnosed with myasthenia gravis (MG) based on lower leg weakness and ptosis for the past 2 months before admission to our hospital. The patient was anti-acetylcholine receptor antibody-positive at admission. He was treated with pyridostigmine bromide and prednisolone, which improved the ptosis, but the lower leg muscle weakness remained. An additional lower leg magnetic resonance imaging examination suggested myositis. Inclusion body myositis (IBM) was diagnosed after a subsequent muscle biopsy. Although MG is often associated with inflammatory myopathy, IBM is rare. There is no effective treatment for IBM, but various treatment possibilities have recently been proposed. This case emphasises that myositis complications, including IBM, should be considered when elevated creatine kinase levels are observed and conventional treatments do not address chronic muscle weakness.

Update on the evaluation and management of dysphagia in sporadic inclusion body myositis

PURPOSE OF REVIEW

Dysphagia is a common symptom of sporadic inclusion body myositis (IBM), affecting disease trajectory and patient quality-of-life. Despite this, it is considerably understudied. The purpose of this review is to summarize current evidence related to the evaluation and management of dysphagia in IBM. We highlight a patient case involving a multidisciplinary management approach, and we encourage continued exploration of exercises for delaying progression and improving impairments in patients with IBM and dysphagia.

RECENT FINDINGS

Recent investigations confirm that dysphagia in IBM is a debilitating and complex symptom that warrants timely evaluation and management. Further, they highlight the lack of validation of standardized swallowing-related metrics specifically for IBM and the limited evidence supporting a consensus of management approaches. Small scale research and clinical anecdotal data support a multidisciplinary and multipronged patient-centered approach, including rehabilitative exercise protocols, for dysphagia management in IBM.

SUMMARY

A paucity exists in the literature to effectively guide clinical decision-making for patients with IBM and dysphagia. Given this, it is our belief that a careful multidisciplinary and multipronged patient-centered approach is critical for dysphagia management in IBM. Prospective, longitudinal research on the underlying mechanisms of swallowing dysfunction using advanced and validated swallowing-related outcome measures is urgently needed.

Efficacy of endoscopic cricopharyngeal myotomy using a curved rigid laryngoscope in patients with sporadic inclusion body myositis: four retrospective case reviews

Sporadic inclusion body myositis (s-IBM) is an acquired degenerative inflammatory myopathy that leads to slowly progressive muscle weakness and atrophy of the limbs, face, and pharynx. Owing to the slow progression of the disease, the indications for surgical intervention remain unclear. Herein, we retrospectively reviewed the records of four patients with s-IBM who had undergone cricopharyngeal myotomy for severe dysphagia at our institution between 2016 and 2021. Among these, one patient underwent transcervical cricopharyngeal myotomy and laryngeal suspension, as videofluoroscopic examination of swallowing revealed poor laryngeal elevation. The remaining three patients underwent endoscopic cricopharyngeal myotomy using a curved rigid laryngoscope. Preoperatively, the mean Hyodo score was 8 points (range: 6-10) using a flexible endoscope. The mean surgical duration was 104 min, and no severe complications were observed. Postoperatively, all patients achieved improvement in swallowing function and food intake. Moreover, swallowing function was maintained in all four patients even 6-12 months postoperatively. Cricopharyngeal myotomy may be a safe surgical procedure with the potential to improve swallowing function, and a Hyodo score of 6 may be considered a surgical indication for cricopharyngeal myotomy in patients with s-IBM.

Diagnosing and managing dysphagia in inclusion body myositis: a systematic review

OBJECTIVES

Dysphagia is a common debilitating clinical feature of IBM. However, the impact of dysphagia in IBM has been historically overlooked. This study aimed to identify, evaluate and summarize the evidence regarding the assessment and management of dysphagia in persons with IBM undergoing treatment.

METHODS

A systematic review was conducted using a multiengine search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Eligible studies had to employ an intervention for persons with IBM, report a swallowing outcome and be published in English. Quality assessments of the eligible studies were performed.

RESULTS

Of 239 studies found, 19 met the inclusion criteria. One study was rated as 'fair' and the rest as 'poor' quality, particularly due to the lack of published and validated swallowing assessment procedures and outcome measures. Cricopharyngeal (CP) dysfunction (12/19) was the most commonly reported swallowing abnormality. Interventions for disease management included pharmacological agents (10/19), followed by surgical (3/19), behavioral (1/19) and combined approaches (5/19). Interventions with immunosuppressants, botulinum toxin injection, balloon dilation and/or CP myotomy led to mixed and transient benefits. Few studies examining statins or behavioral therapies (primarily focused on respiratory function) showed no effects for dysphagia.

CONCLUSION

Various interventions have been reported to temporarily improve dysphagia in persons with IBM. However, these findings are based on limited and overall low-quality evidence. This study cautions against the generalization of these findings and emphasizes the need for further systematic research to improve the diagnosis and management of dysphagia in IBM.

Tendon Transfers for the Treatment of Finger Flexion Weakness in a Patient With Inclusion Body Myositis: A Case Report

CASE

We describe a 71-year-old patient with inclusion body myositis (IBM), characterized by progressive atrophy and weakness in his left upper extremity. This patient underwent extensor carpi radialis longus to flexor pollicis longus and brachioradialis to flexor digitorum profundus tendon transfers in the left upper extremity to reduce IBM-related functional deficits. He had noticeable improvements in finger flexion after the transfers, which have been sustained for 2 years after the procedure.

CONCLUSION

This case reinforces that this novel tendon transfer may be an effective treatment option to improve hand function and activities of daily living in patients with IBM.

Late-onset myopathies: clinical features and diagnosis

Late-onset myopathies are not well-defined since there is no clear definition of 'late onset'. For practical reasons we decided to use the age of 40 years as a cut-off. There are diseases which only manifest as late onset myopathy (inclusion body myositis, oculopharyngeal muscular dystrophy and axial myopathy). In addition, there are diseases with a wide range of onset including 'late onset' muscle weakness. Well-known and rather frequently occurring examples are Becker muscular dystrophy, limb girdle muscular dystrophy, facioscapulohumeral dystrophy, Pompe disease, myotonic dystrophy type 2, and anoctamin-5-related distal myopathy. The above-mentioned diseases will be discussed in detail including clinical presentation - which can sometimes lead someone astray - and diagnostic tools based on real cases taken from the author's practice. Where appropriate a differential diagnosis is provided. Next generation sequencing (NGS) may speed up the diagnostic process in hereditary myopathies, but still there are diseases, e.g. with expansion repeats, deletions, etc, in which NGS is as yet not very helpful.

A Patient with HCV Infection and a Sustained Virological Response to Direct-acting Antiviral Treatment Who Developed Inclusion Body Myositis

We report the case of a 75-year-old woman who was found to have hepatitis C virus (HCV) infection in 1987. Before treatment in 2016, she was found to have mixed cryoglobulinemia (MC). Direct-acting antiviral (DAA) treatment produced a sustained virological response 12 (SVR12). She noticed gradual muscle weakness in 2015 and the gradual development of dysarthria and dysphagia in 2017. We performed a muscle biopsy that showed inclusion body myositis (IBM). To the best of our knowledge, this is first case of a patient with HCV infection, MC, and IBM, in which MC and IBM did not improve after an SVR12 was obtained by DAA treatment.

Dropped Head Syndrome and the Presence of Rimmed Vacuoles in a Muscle Biopsy in Scleroderma-polymyositis Overlap Syndrome Associated with Anti-Ku Antibody

A 66-year-old woman with a history of interstitial lung disease presented with a 3-month history of dropped head syndrome (DHS), followed by camptocormia and extremity weakness. A clinical examination revealed Raynaud phenomenon, arthralgia, distal skin sclerosis, and microbleeds in the nailfold capillaries. An anti-Ku antibody test was positive. A muscle biopsy revealed inflammatory myopathy with rimmed vacuoles (RVs). The diagnosis of scleroderma-polymyositis (SSc-PM) overlap syndrome was made. RVs on a muscle biopsy in a patient with inflammatory myositis involving axial muscles may be seen either in inclusion body myositis or SSc-PM overlap syndrome. The examination of the skin and autoantibody testing help determine the diagnosis and treatment strategy.

Interventions for dysphagia in long-term, progressive muscle disease

BACKGROUND

Normal swallowing function is divided into oral, pharyngeal, and oesophageal phases. The anatomy and physiology of the oral cavity facilitates an oral preparatory phase of swallowing, in which food and liquid are pushed towards the pharynx by the tongue. During pharyngeal and oesophageal phases of swallowing, food and liquid are moved from the pharynx to the stomach via the oesophagus. Our understanding of swallowing function in health and disease has informed our understanding of how muscle weakness can disrupt swallowing in people with muscle disease. As a common complication of long-term, progressive muscle disease, there is a clear need to evaluate the current interventions for managing swallowing difficulties (dysphagia). This is an update of a review first published in 2004.

OBJECTIVES

To assess the effects of interventions for dysphagia in people with long-term, progressive muscle disease.

SEARCH METHODS

On 11 January 2016, we searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, AMED, LILACS, and CINAHL. We checked references in the identified trials for additional randomised and quasi-randomised controlled trials. We also searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform on 12 January 2016 for ongoing or completed but unpublished clinical trials.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials that assessed the effect of interventions for managing dysphagia in adults and children with long-term, progressive muscle disease, compared to other interventions, placebo, no intervention, or standard care. Quasi-randomised controlled trials are trials that used a quasi-random method of allocation, such as date of birth, alternation, or case record number. Review authors previously excluded trials involving people with muscle conditions of a known inflammatory or toxic aetiology. In this review update, we decided to include trials of people with sporadic inclusion body myositis (IBM) on the basis that it presents as a long-term, progressive muscle disease with uncertain degenerative and inflammatory aetiology and is typically refractory to treatment.

DATA COLLECTION AND ANALYSIS

We applied standard Cochrane methodological procedures.

MAIN RESULTS

There were no randomised controlled trials (RCTs) that reported results in terms of the review's primary outcome of interest, weight gain or maintenance. However, we identified one RCT that assessed the effect of intravenous immunoglobulin on swallowing function in people with IBM. The trial authors did not specify the number of study participants who had dysphagia. There was also incomplete reporting of findings from videofluoroscopic investigations, which was one of the review's secondary outcome measures. The study did report reductions in the time taken to swallow, as measured using ultrasound. No serious adverse events occurred during the study, although data for the follow-up period were lacking. It was also unclear whether the non-serious adverse events reported occurred in the treatment group or the placebo group. We assessed this study as having a high risk of bias and uncertain confidence intervals for the review outcomes, which limited the overall quality of the evidence. Using GRADE criteria, we downgraded the quality of the evidence from this RCT to 'low' for efficacy in treating dysphagia, due to limitations in study design and implementation, and indirectness in terms of the population and outcome measures. Similarly, we assessed the quality of the evidence for adverse events as 'low'. From our search for RCTs, we identified two other non-randomised studies, which reported the effects of long-term intravenous immunoglobulin therapy in adults with IBM and lip-strengthening exercises in children with myotonic dystrophy type 1. Headaches affected two participants treated with long-term intravenous immunoglobulin therapy, who received a tailored dose reduction; there were no adverse events associated with lip-strengthening exercises. Both non-randomised studies identified improved outcomes for some participants following the intervention, but neither study specified the number of participants with dysphagia or demonstrated any group-level treatment effect for swallowing function using the outcomes prespecified in this review.

AUTHORS' CONCLUSIONS

There is insufficient and low-quality RCT evidence to determine the effect of interventions for dysphagia in long-term, progressive muscle disease. Clinically relevant effects of intravenous immunoglobulin for dysphagia in inclusion body myositis can neither be confirmed or excluded using the evidence presented in this review. Standardised, validated, and reliable outcome measures are needed to assess dysphagia and any possible treatment effect. Clinically meaningful outcomes for dysphagia may require a shift in focus from measures of impairment to disability associated with oral feeding difficulties.

Sporadic Inclusion Body Myositis Manifesting as Isolated Muscle Weakness of the Finger Flexors Three Years after Disease Onset

Sporadic inclusion body myositis (sIBM) is a chronic progressive myopathy characterized by muscle weakness of both the quadriceps femoris and finger flexors. We herein present the case of a typical male patient with sIBM, which manifested as the isolated weakness of the finger flexors three years after the disease onset. We have identified several patients with sIBM in our cohort with muscle weakness of the flexors but not the quadriceps femoris. Examination of the flexor digitorum profundus muscle is important for the early and proper diagnosis of sIBM, even if a patient only presents with isolated finger flexor muscle weakness.

[Anesthesia for pneumothorax surgery in a patient with type II chronic respiratory failure associated with inclusion body myositis]

A 40-year-old man was scheduled for video assisted thoracoscopic surgery due to pneumothorax. He had been diagnosed with inclusion body myositis and received nocturnal non-invasive positive pressure ventilation. Anesthesia was induced with propofol, remifentanil, and rocuronium, and maintained with propofol, remifentanil and fentanyl. The dosage of rocuronium was 10 mg. Although we administered neostigmine at the end of the operation and TOF ratio was over 90%, he was transported to the ICU with tracheal intubation because of poor spontaneous respiration. On POD 1, the tracheal tube was extubated and NPPV was administered again. Minitrach was inserted on POD 2, and he left the ICU on POD 4. Generally, in patients with myopathy the dose of muscle relaxant should be decreased in proportion to their muscle atrophy. Rocuronium 10 mg was administered in this case and we thought it could be antagonized by neostigmine, but extubation on the day of operation was impossible. We think this is not because of the residual effect of muscle relaxant, but because of decreases in pulmonary function. In this case, we expected long-term mechanical ventilation might be necessary, but he showed a good postoperative course owing to minimally invasive surgery, NPPV, and suctioning of sputum via Minitrach.

Inclusion body myositis: a case of bilateral extremity weakness

Inflammatory myopathy is a common cause of bilateral muscular weakness in adults. Although not as common as polymyositis, inclusion body myositis (IBM) is a form of inflammatory myopathy characterized by chronic progressive muscle inflammation and often goes undiagnosed and untreated. IBM patients most commonly present with proximal lower extremity weakness and may have normal creatine kinase (CK) levels. A high level of clinical suspicion is required for prompt and accurate diagnosis of IBM, which is diagnosed definitively with a muscle biopsy. The patient described in this case report is a 68-year-old man who initially presented with both bilateral symmetric proximal lower extremity and distal upper extremity weakness. IBM was suspected through history, electromyography, and definitively diagnosed with muscle biopsy. The patient was subsequently initiated on prednisone therapy and physical therapy, with improvement in muscular strength after 2 months. In patients presenting with bilateral extremity weakness and normal CK level, the diagnosis of IBM should be included in the differential diagnosis and muscle biopsy performed for appropriate cases.

A rare association of early-onset inclusion body myositis, rheumatoid arthritis and autoimmune thyroiditis: a case report and literature review

Sporadic inclusion body myositis (sIBM) is a slowly progressive, red-rimmed vacuolar myopathy leading to muscular atrophy and progressive weakness; it predominantly affects males older than fifty years, and is resistant to immunotherapy. It has been described in association with immuno-mediated thrombocytopenic purpura, multiple sclerosis, connective tissue disorders and, occasionally, rheumatoid arthritis. A 37-year-old man with longstanding rheumatoid arthritis and autoimmune thyroiditis with hypothyroidism was referred to us with slowly progressive, diffuse muscle weakness and wasting, which had initially involved the volar finger flexors, and subsequently also the ankle dorsiflexors and knee extensors. Needle electromyography showed typical myopathic motor unit potentials, fibrillation and positive sharp waves with normal nerve conduction studies. Quadriceps muscle biopsy was suggestive of sIBM. Considering data published in the literature, this case may be classified as an early-onset form. The patient was treated with long-term intravenous immunoglobulin and obtained a substantial stabilization of his muscle strength.

Primary respiratory failure due to inclusion body myositis: think outside the box

Inclusion body myositis features a slowly progressive inflammatory myopathy characterized by progressive proximal muscle weakness in the lower extremities, followed by proximal, upper-extremity weakness and later involvement of distal muscles groups. Although the most severely affected muscles are those of the limbs, the disease can also involve the respiratory, cardiovascular and gastrointestinal system muscles as well. We describe a unique patient who presented with acute hypercapnic hypoxic respiratory failure secondary to inclusion body myositis. Our patient required mechanical ventilation but responded to corticosteroid therapy. The diagnosis was delayed in part because of the slowly progressive course of the disease and the fact that an extensive investigation had not disclosed a cause. We postulate that muscle biopsy may be warranted in select patients suffering from a protracted muscle weakness.

Long-term follow-up of sporadic inclusion body myositis treated with intravenous immunoglobulin: a retrospective study of 16 patients

OBJECTIVES

Previous studies of intravenous immunoglobulin (IVIG) treatment in sporadic inclusion body myositis (sIBM) have yielded conflicting results. Here, we have undertaken a retrospective assessment of the long-term effects of IVIG in our sIBM cohort.

METHODS

Sixteen sIBM patients, treated with a mean of 10 IVIG infusions and followed up for a mean period of 23 months, were identified. Six sIBM patients treated with other drugs were used as an internal control group. Serial data on manual muscle testing (MMT), laboratory parameters and patients' subjective assessment were collected.

RESULTS

Serial MMT scores were available in 14 IVIG treated patients. Two of these patients improved more than 20% in MMT from baseline up to the third IVIG infusion. One of six patients in the control group showed a similar MMT improvement during the first six months. Improved swallowing function was reported by three IVIG-treated patients, but none of the controls. The serum levels of creatine kinase fell more than 20 % after the first IVIG infusion in 7/16 IVIG-treated patients, but this improvement was not sustained during the follow-up period.

CONCLUSIONS

IVIG treatment appears to have short-term beneficial effects on muscle strength and dysphagia in some few sIBM patients, but these effects are not sustained over time.

The effects of lingual intervention in a patient with inclusion body myositis and Sjögren's syndrome: a longitudinal case study

OBJECTIVE

To report the 5-year course of a patient's swallowing disorder in the context of progressive neuromuscular disease and the effectiveness of a lingual strengthening treatment program.

DESIGN

This is a case report that describes a lingual treatment protocol that was repeated 3 times over a 5-year period with and without maintenance periods.

SETTING

The study was completed in 2 settings-an outpatient swallowing clinic at an acute care hospital and the patient's home.

PARTICIPANT

The subject was a 77-year-old woman who was diagnosed with inclusion body myositis and Sjögren's syndrome.

INTERVENTION

The patient participated in an intensive 8-week lingual strengthening protocol 3 times (at years 1, 4, and 5) and a subsequent maintenance program twice (at years 4 and 5).

MAIN OUTCOME MEASURES

Three outcome measures were collected during the study: (1) lingual manometric pressures at the anterior and posterior tongue, measured by using a lingual manometric device, (2) airway invasion measured by using an 8-point Penetration-Aspiration Scale, and (3) clearance of the bolus measured by using a 3-point residue scale.

RESULTS

Isometric lingual strengthening was effective in maintaining posterior tongue lingual pressure and Penetration-Aspiration Scale scores during the treatment periods. Residue scale scores did not significantly change during treatment.

CONCLUSIONS

We conclude that, in this patient, lingual strengthening slowed the progression of disease-related lingual strength loss and extended functional swallowing performance. Thus, this type of intervention may hold promise as an effective swallowing treatment option for patients with neurodegenerative inflammatory diseases such as inclusion body myositis and Sjögren's syndrome.

Inclusion body myositis in Alzheimer's disease

BACKGROUND

The prevalence of Alzheimer's disease is increasing. Could findings of similar deposits in brain and muscle tissue explain this increase? The purpose of this report is to illustrate that Alzheimer's disease and inclusion body myositis may share a common aetiology.

RESULTS

We present a case where Alzheimer's disease and inclusion body myositis coexist in the same patient. Amyloid-beta deposition and the presence of phosphorylated tau protein have been noted in brain tissue and in muscle biopsy from patients with these disorders.

METHODS

Electrophysiological methods are needed for proper diagnosis of this brain and muscle disorder. Recent data on deposit structures in both conditions may indicate an environmental aetiology for Alzheimer's disease and inclusion body myositis.

CONCLUSION

By combining electrophysiological methods with muscle biopsy in cases of Alzheimer's disease, the possible aetiological connection between simultaneous affection of both muscle and brain in this condition can be established.

[Primary Sjögren syndrome and inclusion body myositis]

The authors report the case of a 69-years-old woman with Sjögren's syndrome. After 8 years of disease she developed muscle weakness and the diagnosis of inclusion body myositis was established. This is a rare association. The patient had a good response to the immunosupressive treatment. Similar cases can be found in the literature and there seems to be a subset of inclusion body myositis associated with autoimmune diseases that shows a better response to treatment and a more favourable prognosis.

An Italian family with inclusion-body myopathy and frontotemporal dementia due to mutation in theVCP gene

Mutations of the valosin-containing protein gene (VCP) are responsible for autosomal-dominant hereditary inclusion-body myopathy associated with frontotemporal dementia and Paget's disease of bone. We identified the p.R155C missense mutation in the VCP gene segregating in an Italian family with three affected siblings, two of whom had a progressive myopathy associated with dementia, whereas one exhibited a progressive myopathy and preclinical signs of Paget's disease of bone. Our study demonstrates that VCP mutations are found in patients of Italian background and may lead to a variable clinical phenotype even within the same kinship.

Inclusion body myopathy and frontotemporal dementia caused by a novel VCP mutation

Hereditary inclusion body myopathy (IBM) with Paget's disease of the bone (PDB) and frontotemporal dementia (FTD) is a rare autosomal dominant disease caused by mutations in the valosin-containing protein (VCP) gene. We report a novel heterozygous VCP gene mutation (R159C) in a 69-year-old Italian patient presenting with slowly progressive muscle weakness of the distal upper and proximal lower limbs since the age of 50 years, 18 years later FTD supervened. No dementia or myopathies were revealed in the family history covering two generations. Degenerative changes and rimmed vacuoles together with VCP- and ubiquitin-positive cytoplasmic and nuclear aggregates were observed at the muscle biopsy. Several elements support the pathogenic role of the R159C VCP gene mutation: the occurrence at the same codon of a different, previously identified pathogenic mutation within a VCP gene mutational hot-spot, the histopathological and biochemical evidence of muscle VCP accumulation and the combined clinical presentation of IBM and FTD. These findings suggest VCP gene investigation even in apparently sporadic cases.

Valosin-containing protein and the pathogenesis of frontotemporal dementia associated with inclusion body myopathy

Frontotemporal dementia with inclusion body myopathy and Paget's disease of bone (IBMPFD) is a rare, autosomal dominant disorder caused by mutations in the gene valosin-containing protein (VCP). The CNS pathology is characterized by a novel pattern of ubiquitin pathology distinct from sporadic and familial frontotemporal lobar degeneration with ubiquitin-positive inclusions without VCP mutations. Yet, the ubiquitin-positive inclusions in IBMPFD also stain for TAR DNA binding protein, a feature that links this rare disease with the pathology associated with the majority of sporadic FTD as well as disease resulting from different genetic alterations. VCP, a member of the AAA-ATPase gene family, associates with a plethora of protein adaptors to perform a variety of cellular processes including Golgi assembly/disassembly and regulation of the ubiquitin-proteasome system. However, the mechanism whereby mutations in VCP lead to CNS, muscle, and bone disease is largely unknown. In this report, we review current literature on IBMPFD, focusing on the pathology of the disease and the biology of VCP with respect to IBMPFD.

Dysphagia in inflammatory myopathy: clinical characteristics, treatment strategies, and outcome in 62 patients

OBJECTIVE

To assess the clinical characteristics, treatment, and outcome of patients with inflammatory myopathy-associated dysphagia.

PATIENTS AND METHODS

We retrospectively reviewed the medical records of all patients with inflammatory myopathy-associated dysphagia seen at the Mayo Clinic in Rochester, Minn, between January 1, 1997, and December 31, 2001.

RESULTS

A total of 783 patients were diagnosed as having inflammatory myopathy during the 5-year study period. Of these, 62 patients (41 women and 21 men; mean age, 68.6 years) had inflammatory myopathy-associated dysphagia: 26 with inclusion body myositis (IBM), 18 with dermatomyositis, 9 with polymyositis, and 9 with overlap syndrome. Dysphagia was a presenting symptom in 13 patients (21%), with the highest incidence in the IBM group. Videofluoroscopic examinations revealed pharyngeal pooling and impaired oropharyngeal and cricopharyngeal function. The benefits of swallowing compensation techniques and exercises were difficult to establish. Interventional procedures were performed in 24 patients (39%) and most frequently (62%) in patients with IBM, with cricopharyngeal myotomy being most beneficial. Patients with IBM had the least symptomatic improvement. Overall, 11 patients died during the median follow-up of 38 months, with respiratory failure due to aspiration pneumonia as the most common cause. Mortality was high in patients who required percutaneous endoscopic gastrostomy (7/11, 64%), and 1- year mortality was highest (31%) in those with dermatomyositis.

CONCLUSION

Dysphagia is a serious and at times presenting problem in patients with inflammatory myopathy. It occurs most frequently and appears to be most refractory in patients with IBM. The mortality rate was high in patients who required percutaneous endoscopic gastrostomy, and the 1-year mortality rate was the highest in patients with dermatomyositis.

Celiac disease and antibodies associated with celiac disease in patients with inflammatory myopathy

Celiac disease is usually associated with autoimmune disorders and has occasionally been reported in patients with inflammatory myopathies. Our aim was to determine the presence of celiac disease and antibodies associated with celiac disease in patients with inflammatory myopathies and to investigate their relationship. Serum antigliadin, anti-tissue transglutaminase, and antiendomysial antibodies were determined in 51 patients with inflammatory myopathies. HLA-DQ2 and -DQ8 alleles were studied to assess their complementary diagnostic value. Jejunal biopsy was performed in patients with moderate to high levels of antigliadin antibodies. Patients with jejunal histology consistent with celiac disease initiated a gluten-free diet. Seventeen patients (31%) were positive for antigliadin antibodies, which were significantly more frequent in patients with inclusion-body myositis than dermatomyositis (P < 0.001). Positive status to HLA-DQ2 and/or -DQ8 did not differ between antigliadin-positive (75% and 12.5%) or -negative (60% and 15%) patients. Three of five jejunal biopsies were diagnostic for celiac disease with histological normalization after a gluten-free diet. Thus, celiac disease is more prevalent in patients with inflammatory myopathies than in the general population. Positive status to HLA-DQ2 allele, which is known to be more frequent in patients with inflammatory myopathies, could explain the high prevalence of antigliadin antibodies in this population. The diagnostic value of HLA-DQ2 or -DQ8 haplotypes to detect celiac disease in patients with inflammatory myopathy is limited.

[Renal involvement by AA amyloidosis in inclusion body myositis]

Inclusion body myositis is currently considered a variant of adult inflammatory myopathies. Clinical course is insidious and besides typical proximal muscles disorder, extension to distal ones is found in up to 95% of cases. Mean survival ranges from 3 to 5 years. Infections are the first death cause, secondary to existing disability a few years after diagnosis. Chronic rheumatic diseases related amyloidosis has became the most frequent kind of reactive amyloidosis or AA amyloidosis. Clinical manifestations of AA amyloidosis mainly affect the kidney. We present the case of a woman with Inclusion body myositis and renal involvement by AA amyloidosis. In our review of literature we haven t found any article relating AA amyloidosis with idiopathic inflammatory myopathies of the adult, what would turn this case into the first ever reported. We can probably find the reason in the bad prognosis of this entity. So we propose making a renal biopsy to all those patients with a long lasting rheumatologic disease and unexpected impaired renal function.

Pediatric macrophagic myofasciitis associated with motor delay

BACKGROUND

Macrophagic myofasciitis (MMF) is a rare inflammatory myopathy characterized by accumulation of perifascicular macrophages without muscle fiber necrosis. Few sporadic pediatric cases have been described, and MMF is recognized as a possible reaction to intramuscular injections of aluminum-containing vaccines. The association of MMF and motor delay is unclear in the pediatric population. We report the clinical evaluation and follow-up of 4 young children with MMF and review of 4 cases previously reported of sporadic, pediatric MMF to better determine the possible association of sporadic MMF in children presenting with motor delay.

PATIENTS AND METHODS

Described our 4 case reports in which we observed children presenting for evaluation of motor delay with unrevealing clinical and laboratory evaluations for common causes of motor delay and histopathological evaluations consistent with macrophagic myofasciitis. Muscle data was obtained by quadriceps muscle biopsy.

RESULTS

Clinical presentations were similar in all children and were characterized by motor delay, hypotonia, and failure to thrive with an unrevealing evaluation for central nervous system disease, congenital, and mitochondrial myopathies.

CONCLUSIONS

Our cases and those previously reported in the literature demonstrate MMF should be considered in the evaluation of children with failure to thrive, hypotonia, and muscle weakness, as clinical outcome appears to be favorable.

Inclusion body myopathy-associated mutations in p97/VCP impair endoplasmic reticulum-associated degradation

Mutations in the AAA+ protein (ATPase associated with a variety of cellular activities) p97/VCP (valosin-containing protein) cause a dominantly inherited syndrome of inclusion body myopathy with Paget's disease of the bone and fronto-temporal dementia (IBMPFD). p97/VCP is a ubiquitously expressed protein that participates in a number of cellular processes including endoplasmic reticulum-associated degradation (ERAD). p97/VCP aids in the extraction of ubiquitinated proteins from the endoplasmic reticulum (ER) and facilitates their delivery to the proteasome. This study focuses on the effects of disease-associated p97/VCP mutations on this pathway. We show that p97/VCP containing the most prevalent IBMPFD-associated mutation, R155H, has normal ATPase activity and hexameric structure. However, when expressed in cultured cells, both this and a second IBMPFD-associated p97/VCP mutant increase the overall level of ubiquitin-conjugated proteins and specifically impair degradation of mutant DeltaF508-CFTR handled by the ERAD pathway. These effects are similar to those previously described for an ATPase deficient p97/VCP mutant and suggest that IBMPFD mutations impair p97/VCP cellular function. In a subset of cells, IBMPFD mutations also promote formation of aggregates that contain p97/VCP, ubiquitin conjugates and ER-resident proteins. Undegraded mutant DeltaF508-CFTR also accumulates in these aggregates. We conclude that IBMPFD mutations in p97/VCP disrupt ERAD and that this may contribute to the pathogenesis of IBMPFD.

Inclusion body myopathy and Paget disease is linked to a novel mutation in the VCP gene

Mutations in the valosin-containing protein (VCP) on chromosome 9p13-p12 were recently found to be associated with hereditary inclusion body myopathy, Paget disease of the bone, and frontotemporal dementia (IBMPFD). We identified a novel missense mutation in the VCP gene (R159H; 688G>A) segregating with this disease in an Austrian family of four affected siblings, who exhibited progressive proximal myopathy and Paget disease of the bone but without clinical signs of dementia.

PM-Scl-Antikörper positive systemische Sklerodermie assoziiert mit Einschlusskörper-Myositis

We describe a 72- year-old patient with a ten year history of anti-PM-Scl positive systemic sclerosis associated with inclusion-body myositis. While the association of dermatomyositis and polymyositis with anti-PM-Scl positive systemic sclerosis is frequently reported, inclusion-body myositis was, to the best of our knowledge, only previously described once in association with anti-PM-Scl-positive systemic sclerosis. The distinction between inclusion-body myositis and other forms of inflammatory myopathy, like the histopathologically well distinguishable polymyositis or dermatomyositis, is relevant because of the poor response of inclusion- body myositis to immunosuppressive treatment. Our case underlines that in patients with anti-PM-Scl-positive systemic sclerosis and treatment resistant progressive myopathy the diagnosis of inclusion body myositis should be considered.

IBM-type inclusions in a patient with slow-channel syndrome caused by a mutation in the AChR epsilon subunit

We report a patient with a slow-channel congenital myasthenic syndrome who carries a novel slow-channel mutation in the epsilon subunit of the acetylcholine receptor and has tubulofilamentous inclusion bodies, in skeletal muscle of the type observed in hereditary and sporadic inclusion body myositis. Ultrastructural analysis of a muscle specimen obtained at the age of 9 years showed an endplate myopathy typical of the slow-channel syndrome. Twenty years later, a second muscle specimen again showed the endplate myopathy as well numerous nuclear and cytoplasmic tubulofilamentous inclusion bodies. Molecular genetic studies revealed a novel valine to phenylalanine mutation (epsilonV259F) in the M2 domain of the acetylcholine receptor. Coexistence of the slow-channel syndrome with a feature of IBM has not been observed before.

Positive troponin T without cardiac involvement in inclusion body myositis

Cardiac troponin T (cTnT) is considered as a specific marker for acute myocardial infarction. Here, we present a case with elevated cTnT, determined by a third-generation assay, without signs of a myocardial lesion. Routine investigation of a 66-year-old female patient with indolent B-cell lymphoma revealed increased serum levels of creatine kinase (CK), MB fraction of CK (CK-MB), and cTnT, although she did not complain of cardiac symptoms. Electrocardiographic monitoring, echocardiography, magnetic resonance computed angiography, and percutaneous coronary angiography excluded myocardial damage. However, the close follow-up showed a steady increase of CK-MB and cTnT levels and gradual development of weakness in both thighs. A biopsy of the right quadriceps muscle led to the diagnosis of inclusion body myositis. In contrast to cTnT, cardiac troponin I could not be detected retrospectively in any of her serum samples. These results demonstrate for the first time that cTnT is elevated in patients with inclusion body myositis.

Use of a cell-free system to determine UDP-N-acetylglucosamine 2-epimerase and N-acetylmannosamine kinase activities in human hereditary inclusion body myopathy

Hereditary inclusion body myopathy (HIBM) is an autosomal recessive neuromuscular disorder associated with mutations in uridine diphosphate (UDP)-N-acetylglucosamine (GlcNAc) 2-epimerase (GNE)/N-acetylmannosamine (ManNAc) kinase (MNK), the bifunctional and rate-limiting enzyme of sialic acid biosynthesis. We developed individual GNE and MNK enzymatic assays and determined reduced activities in cultured fibroblasts of patients, with HIBM harboring missense mutations in either or both the GNE and MNK enzymatic domains. To assess the effects of individual mutations on enzyme activity, normal and mutated GNE/MNK enzymatic domains were synthesized in a cell-free in vitro transcription-translation system and subjected to the GNE and MNK enzymatic assays. This cell-free system was validated for both GNE and MNK activities, and it revealed that mutations in one enzymatic domain (in GNE, G135V, V216A, and R246W; in MNK, A631V, M712T) affected not only that domain's enzyme activity, but also the activity of the other domain. Moreover, studies of the residual enzyme activity associated with specific mutations revealed a discrepancy between the fibroblasts and the cell-free systems. Fibroblasts exhibited higher residual activities of both GNE and MNK than the cell-free system. These findings add complexity to the tightly regulated system of sialic acid biosynthesis. This cell-free approach can be applied to other glycosylation pathway enzymes that are difficult to evaluate in whole cells because their substrate specificities overlap with those of ancillary enzymes.

Reversible inflammatory and vacuolar myopathy with vitamin E deficiency in celiac disease

We report a patient with late-onset celiac disease and neurological manifestations including myopathy, polyneuropathy, and ataxia. Laboratory investigations showed anti-gliadin antibodies and severe vitamin E deficiency. Muscle biopsy revealed inflammatory infiltrates and rimmed vacuoles, similar to those found in inclusion-body myositis. A gluten-free diet and vitamin E supplementation reversed both the clinical neurological manifestations and the abnormalities in the muscle biopsy. Anti-gliadin antibodies were no longer present. This case illustrates the spectrum of neurological complications of celiac disease and documents the occurrence of reversible pathology resembling inclusion-body myopathy in the muscle.

Steroid-responsive inclusion body myositis associated with endometrial cancer

Inclusion body myositis (IBM) is an uncommon chronic inflammatory myopathy. Although the association between other myopathies and cancer has been well established, the relationship between IBM and neoplasia is not completely understood. Unlike polymyositis (PM) or dermatomyositis (DM), IBM rarely responds to immunosuppressive treatment and the response is seldom long-lasting. We describe a case of IBM associated with endometrial carcinoma that also demonstrated a unique response to steroids alone which persisted despite cancer relapse. The factors that are associated with a response of IBM to steroids are discussed. An atypical, steroid-responsive form of the disease is delineated.

Inclusion body myositis in connective tissue disorders: case report and review of the literature

We report a patient with systemic lupus erythematosus (SLE) and secondary Sjögren's syndrome (SS) who developed inclusion body myositis (IBM) which, contrary to the typical presentation of this disorder, was symmetrical in nature although the diagnosis was only made after electron microscopy was performed. Therapy with increased doses of methotrexate proved to be beneficial, with the patient having full recovery after 8 months of therapy. It appears that a subset of IBM may be related to autoimmune disorders, an issue that was disputed in the past, and these patients may have a better prognosis than typical IBM patients. This is the first case report of IBM in a patient who had the dual diagnosis of SLE and SS.

Coexistence of X-linked recessive Emery-Dreifuss muscular dystrophy with inclusion body myositis-like morphology

We reported three cases (two familial and one sporadic) of X-linked Emery-Dreifuss muscular dystrophy (EDMD), genetically documented. Two patients demonstrated a typical inclusion body myositis (IBM)-like morphology. The third patient had only minor changes. Patients had elbow and ankle contractures, progressive wasting of humeroperoneal muscles and cardiac failure (pacemaker implantation in all). There was a mutation within the Xq28 gene and complete absence of emerin in the nuclear membrane. Mononuclear cell infiltrations, rimmed vacuoles, amyloid deposits, as well as cytoplasmic and nuclear tubulofilamentous muscle inclusions were most unusual findings. Coexistence of IBM-like morphology and X-linked recessive EDMD might indicate that pathological features of IBM are nonspecific and may be present in other neuromuscular disorders.

Injection of Botulinum Toxin a to Upper Esophageal Sphincter for Oropharyngeal Dysphagia in Two Patients with Inclusion Body Myositis

Inclusion body myositis (IBM) is a progressive degenerative skeletal muscle disease leading to weakening and atrophy of both proximal and distal muscles. Dysphagia is reported in up to 86% of IBM patients. Surgical cricopharyngeal myotomy may be effective for cricopharyngeal dysphagia and there is one published report that botulinum toxin A, injected into the cricopharyngeus muscle using a hypopharyngoscope under general anesthesia, relieved IBM-associated dysphagia. This report presents the first documentation of botulinum toxin A injection into the upper esophageal sphincter using a flexible esophagogastroduodenoscope under conscious sedation, to reduce upper esophageal sphincter pressure and successfully alleviate oropharyngeal dysphagia in two IBM patients.

Creutzfeldt-Jakob disease and inclusion body myositis: Abundant disease-associated prion protein in muscle

Pathologicalprion protein (PrP(Sc)) is the hallmark of prion diseases affecting primarily the central nervous system. Using immunohistochemistry, paraffin-embedded tissue blot, and Western blot, we demonstrated abundant PrP(Sc) in the muscle of a patient with sporadic Creutzfeldt-Jakob disease and inclusion body myositis. Extraneural PrP(C)-PrP(Sc) conversion in Creutzfeldt-Jakob disease appears to become prominent when PrP(C) is abundantly available as substrate, as in inclusion body myositis muscle.

Clinical and genetic heterogeneity in chromosome 9p associated hereditary inclusion body myopathy: exclusion of GNE and three other candidate genes

We have previously reported a new autosomal dominant inclusion body myopathy clinically resembling limb girdle muscular dystrophy, associated with Paget disease of bone in the majority and frontotemporal dementia in a third of individuals. The critical locus for this unique disorder now termed IBMPFD is 9 p21.1-p12, spans 5.5 Mb and contains the gene responsible for the recessive quadriceps-sparing inclusion body myopathy (IBM2). Mutation analysis of the GNE gene associated with IBM2 in affected individuals from four IBMPFD families did not identify any mutations, indicating that the two disorders are not allelic. Expression studies indicate that GNE has a tissue-specific splice pattern, with four splice variants. Mutation analysis in three other candidate genes (beta-tropomyosin, NDUFB6 and SMU1) did not identify any mutations.

Inclusion body myositis associated with celiac sprue and idiopathic thrombocytopenic purpura

We report an unusual case of a 51-year-old woman with inclusion body myositis associated with celiac sprue and idiopathic thrombocytopenic purpura. We propose that the presence of all three disorders together suggests that they may share an interrelated immune mechanism.

Inclusion body myositis--sensory dysfunction revealed with quantitative determination of somatosensory thresholds

In order to evaluate sensory function in inclusion body myositis (IBM), nine patients were subjected to sensibility screening and quantitative determination of somatosensory thresholds. Data were compared with results from electrophysiological examination and muscle biopsy. On sensibility screening all but one of the IBM patients had abnormal findings in hands and/or feet mostly affecting thermal sensibility. Vibratory thresholds were abnormal in five and thermal thresholds in four of the patients. Mean vibratory thresholds were significantly (P < 0.05) higher in the IBM patients when compared with the controls. Significantly increased heat pain thresholds were found in hands and feet when compared with the controls while thermal thresholds were normal. Nerve conduction velocities were decreased in three patients, EMG showed both myopathic and neuropathic abnormalities in six patients. Eight patients had neuropathic abnormalities on muscle biopsy. The sensory dysfunction found suggests an affection of peripheral nerves in IBM mainly affecting large diameter myelinated nerve fibres corroborating earlier findings of a peripheral neuropathy in IBM.