Anti-nuclear matrix protein 2 antibody-positive dermatomyositis with gastrointestinal ulcers: A case report

Gastrointestinal manifestations are a very rare complication of dermatomyositis (DM) and are much less frequent in adult cases than in juvenile cases. Only a few previous papers have reported adult patients who had DM with anti-nuclear matrix protein 2 (anti-NXP2) antibodies and who developed gastrointestinal ulcers. Herein, we report a similar case of a 50-year-old man who had DM with anti-NXP2 antibodies followed by relapsing multiple gastrointestinal ulcers. Even after the administration of prednisolone, his muscle weakness and myalgia deteriorated and gastrointestinal ulcers relapsed. In contrast, intravenous immunoglobulin and azathioprine improved his muscle weakness and gastrointestinal ulcers. Based on the parallel disease activity of the muscular and gastrointestinal symptoms, we considered that his gastrointestinal ulcers were a complication of DM with anti-NXP2 antibodies. We also propose that early intensive immunosuppressive therapy would be required for the muscular and gastrointestinal symptoms in DM with anti-NXP2 antibodies.

The effect of immunosuppressive therapy on cardiac involvements in anti-mitochondrial antibody-positive myositis

AIMS

Anti-mitochondrial antibody (AMA)-positive myositis is frequently associated with various cardiac involvements, such as arrhythmia and left ventricular (LV) dysfunction. However, the efficacy of immunosuppressive therapy in these complications remains unknown. This study aimed to investigate the cardiac response to immunosuppressive therapy in patients with AMA-positive myositis.

METHODS AND RESULTS

The clinical data of 15 AMA-positive myositis patients with cardiac involvement were retrospectively collected at our centre. To evaluate the effects of immunosuppressive therapy, echocardiographic and laboratory data of patients who received glucocorticoid therapy with additional immunosuppressants (n = 6) and those who did not (n = 6) were compared. Also, the characteristics of patients with or without >5% LV ejection fraction (LVEF) decline during the follow-up period (n = 5 vs. n = 7) were compared. Thirteen patients (87%) had arrhythmias, and eight patients (53%) had LV wall motion abnormalities. Although arrhythmias decreased after treatment, reduced LVEF and LV wall motion abnormalities persisted. Further investigation revealed an increased LV end-systolic dimension and reduced LVEF in patients without additional immunosuppressive therapy, while those in patients with additional immunosuppressive therapy were maintained. Six of seven patients (86%) without LVEF decline received additional immunosuppressive therapy, whereas no patients with LVEF decline had additional immunosuppressive therapy.

CONCLUSIONS

Cardiac involvement in AMA-positive myositis may worsen even with glucocorticoid monotherapy, and there might be some associations between the change of LV function and additional immunosuppressive therapy.

Cranial Nerve Involvement and Dysautonomia in Post-COVID-19 Guillain-Barré Syndrome

The clinical characteristics of Guillain-Barré syndrome (GBS) after coronavirus disease 2019 (COVID-19) remain unclear due to the small number of cases. We herein report a case of a Japanese patient with post-COVID-19 GBS who presented with facial and limb muscle weakness, sensory deficits, and autonomic dysfunction. Nerve conduction studies revealed demyelination. Head magnetic resonance imaging showed contrast enhancement in the bilateral facial nerves. Systemic management, including intubation, intravenous immunoglobulin therapy, and rehabilitation, improved the patient's condition. This was the first Japanese case of acute inflammatory demyelinating polyneuropathy after COVID-19 and was characterized by autonomic dysfunction and facial nerve enhancement.

Anti-Ku Antibody-Positive Myositis Presenting as a Wide Range of Axial Myopathies and Myocarditis: A Case Report and Review of the Literature

Idiopathic inflammatory myopathies (IIMs) are autoimmune diseases predominantly affecting proximal muscles; paraspinal muscle involvement is relatively rare. Because paraspinal myopathies do not always cause clinically-evident symptoms, the diagnosis of IIMs with axial myopathies can be challenging. Anti-Ku autoantibodies, initially reported in polymyositis/systemic sclerosis overlap syndrome, are myositis-associated antibodies (MAAs) observed in patients with a wide variety of connective tissue diseases (CTDs). Few reports have been published demonstrating predominant axial myopathy in IIM patients with anti-Ku antibodies. Herein, we investigated a previously healthy Japanese woman in her early 70s who presented with Raynaud's phenomenon, back pain, and exertional dyspnea. The creatine kinase (CK) was elevated and antinuclear antibody staining was positive, but myositis-specific antibodies (MSAs) were negative. Magnetic resonance imaging (MRI) revealed myocarditis and a wide range of axial muscle inflammation, including bilateral thoracolumbar paraspinal, infraspinatus, and trapezius muscles. The muscle biopsy was consistent with IIM. In addition, anti-Ku antibody was positive. Administration of prednisolone and tacrolimus quickly alleviated the symptoms and the CK level returned to normal. The diagnosis of IIM was arduous in this case because she did not present with camptocormia, muscle weakness involving the proximal limbs was not apparent, and MSAs were negative. Whether axial myopathy and myocarditis are more prevalent in IIM patients with than without anti-Ku antibodies is uncertain. Clinicians should suspect axial myopathy and MAAs, such as anti-Ku antibodies, especially in patients in whom muscle weakness of the proximal limbs is not noticeable.

Expansion of GGC Repeat in GIPC1 Is Associated with Oculopharyngodistal Myopathy

Oculopharyngodistal myopathy (OPDM) is an adult-onset inherited neuromuscular disorder characterized by progressive ptosis, external ophthalmoplegia, and weakness of the masseter, facial, pharyngeal, and distal limb muscles. The myopathological features are presence of rimmed vacuoles (RVs) in the muscle fibers and myopathic changes of differing severity. Inheritance is variable, with either putative autosomal-dominant or autosomal-recessive pattern. Here, using a comprehensive strategy combining whole-genome sequencing (WGS), long-read whole-genome sequencing (LRS), linkage analysis, repeat-primed polymerase chain reaction (RP-PCR), and fluorescence amplicon length analysis polymerase chain reaction (AL-PCR), we identified an abnormal GGC repeat expansion in the 5' UTR of GIPC1 in one out of four families and three sporadic case subjects from a Chinese OPDM cohort. Expanded GGC repeats were further confirmed as the cause of OPDM in an additional 2 out of 4 families and 6 out of 13 sporadic Chinese individuals with OPDM, as well as 7 out of 194 unrelated Japanese individuals with OPDM. Methylation, qRT-PCR, and western blot analysis indicated that GIPC1 mRNA levels were increased while protein levels were unaltered in OPDM-affected individuals. RNA sequencing indicated p53 signaling, vascular smooth muscle contraction, ubiquitin-mediated proteolysis, and ribosome pathways were involved in the pathogenic mechanisms of OPDM-affected individuals with GGC repeat expansion in GIPC1. This study provides further evidence that OPDM is associated with GGC repeat expansions in distinct genes and highly suggests that expanded GGC repeat units are essential in the pathogenesis of OPDM, regardless of the genes in which the expanded repeats are located.

[Idiopathic Inflammatory Myopathy and Anti-aminoacyl-tRNA Synthetase Antibody]

Anti-aminoacyl-tRNA synthetase (ARS) antibodies (anti-Jo-1, anti-PL-7, anti-PL-12, anti-EJ, anti-KS, anti-OJ, anti-Ha, and anti-Zo antibodies) are found in 25 to 40% of myositis patients. The patients with these antibodies have anti-synthetase syndrome with one or more of the following clinical features: myositis, interstitial lung disease, arthritis, fever, Raynaud's phenomenon, and mechanic's hands. In Japan, health insurance coverage of treatments for patients in whom the "anti-ARS antibodies," anti-Jo-1, anti-PL-7, anti-PL-12, anti-EJ, and anti-KS are detected by enzyme-linked immunosorbent assay was approved by the Ministry of Health, Labour and Welfare in 2014. Recently, clinical features have been discovered to be heterogeneous. Patients with the anti-PL-7, anti-PL-12, anti-KS, and anti-OJ antibodies exhibit interstitial lung disease rather than myositis. Interstitial lung disease is related to the prognosis of this syndrome. Regarding histopathological findings of the muscle, perimysial connective tissue fragmentation with positive staining for alkaline phosphatase is the characteristic feature. Myonuclear actin filament inclusions are also detected. A recent work demonstrated that immunization of mice with histidyl-tRNA synthetase results in muscle inflammation consistent with myositis. These findings promote understanding of the pathological mechanism of the development of myositis associated with anti-ARS antibodies.

Clinicopathologic features of myositis patients with CD8-MHC-1 complex pathology

Objective:

To determine the clinical features of myositis patients with the histopathologic finding of CD8-positive T cells invading non-necrotic muscle fibers expressing major histocompatibility complex class 1 (CD8-MHC-1 complex), which is shared by polymyositis (PM) and inclusion body myositis (IBM), in relation to the p62 immunostaining pattern of muscle fibers.

Methods:

All 93 myositis patients with CD8-MHC-1 complex who were referred to our hospital from 1993 to 2015 were classified on the basis of the European Neuromuscular Center (ENMC) diagnostic criteria for IBM (Rose, 2013) or PM (Hoogendijk, 2004) and analyzed.

Results:

The 93 patients included were 17 patients with PM, 70 patients with IBM, and 6 patients who neither met the criteria for PM nor IBM in terms of muscle weakness distribution (unclassifiable group). For these PM, IBM, and unclassifiable patients, their mean ages at diagnosis were 63, 70, and 64 years; autoimmune disease was present in 7 (41%), 13 (19%), and 4 (67%); hepatitis C virus infection was detected in 0%, 13 (20%), and 2 (33%); and p62 was immunopositive in 0%, 66 (94%), and 2 (33%), respectively. Of the treated patients, 11 of 16 PM patients and 4 of 6 p62-immunonegative patients in the unclassifiable group showed responses to immunotherapy, whereas all 44 patients with IBM and 2 p62-immunopositive patients in the unclassifiable group were unresponsive to immunotherapy.

Conclusions:

CD8-MHC-1 complex is present in patients with PM, IBM, or unclassifiable group. The data may serve as an argument for a trial of immunosuppressive treatment in p62-immunonegative patients with unclassifiable myositis.

Cancer association as a risk factor for anti-HMGCR antibody-positive myopathy

Objective:

To show cancer association is a risk factor other than statin exposure for anti-3-hydroxy-3-methylglutaryl coenzyme A reductase autoantibody-positive (anti-HMGCR Ab+) myopathy.

Methods:

We analyzed the clinical features and courses of 33 patients (23 female and 10 male) with anti-HMGCR Ab+ myopathy among 621 consecutive patients with idiopathic inflammatory myopathies.

Results:

Among the 33 patients, 7 (21%) were statin-exposed and 26 were statin-naive. In relation with cancer, there were 12 patients (statin-exposed, n = 4) with cancers detected within 3 years of myopathy diagnosis (cancer association), 3 patients (all statin-naive) with cancers detected more than 3 years before myopathy diagnosis (cancer history), 10 cancer-free patients followed up for more than 3 years (all statin-naive), and 8 patients without cancer detection but followed up for less than 3 years (statin-exposed, n = 3). Therefore, 12 patients with cancer association (36%) formed a larger group than that of 7 statin-exposed patients (21%). Among 12 patients with cancer association, 92% had cancer detection within 1 year of myopathy diagnosis (after 1.3 years in the remaining patient), 83% had advanced cancers, and 75% died of cancers within 2.7 years. Of interest, 1 patient with cancer history had sustained increase in creatine kinase level over 12 years from cancer removal to the development of weakness.

Conclusions:

Patients with cancer association formed a large group with poor prognosis in our series of patients with anti-HMGCR Ab+ myopathy. The close synchronous occurrence of cancers and myopathies suggested that cancer association is one of the risk factors for developing anti-HMGCR Ab+ myopathy.

Anti-TIF1-γ antibody and cancer-associated myositis: A clinicohistopathologic study

OBJECTIVE

We aimed to analyze the clinical and histopathologic features of cancer-associated myositis (CAM) in relation to anti-transcriptional intermediary factor 1 γ antibody (anti-TIF1-γ-Ab), a marker of cancer association.

METHODS

We retrospectively studied 349 patients with idiopathic inflammatory myopathies (IIMs), including 284 patients with pretreatment biopsy samples available. For the classification of IIMs, the European Neuromuscular Center criteria were applied. Patients with CAM with (anti-TIF1-γ-Ab[+] CAM) and without anti-TIF1-γ-Ab (anti-TIF1-γ-Ab[-] CAM) were compared with patients with IIM without cancers within and beyond 3 years of myositis diagnosis.

RESULTS

Cancer was detected in 75 patients, of whom 36 (48%) were positive for anti-TIF1-γ-Ab. In anti-TIF1-γ-Ab(+) patients with CAM, cancers were detected within 1 year of myositis diagnosis in 35 (97%) and before 1 year of myositis diagnosis in 1. All the anti-TIF1-γ-Ab(+) patients with CAM satisfied the dermatomyositis (DM) criteria, including 2 possible DM sine dermatitis cases, and were characterized histologically by the presence of perifascicular atrophy, vacuolated fibers (VFs), and dense C5b-9 deposits on capillaries (dC5b-9). In contrast, 39 anti-TIF1-γ-Ab(-) patients with CAM were classified into various subgroups, and characterized by a higher frequency of necrotizing autoimmune myopathy (NAM). Notably, all 7 patients with CAM classified into the NAM subgroup were anti-TIF1-γ-Ab(-) and exhibited no dC5b-9 or VFs.

CONCLUSIONS

CAM includes clinicohistopathologically heterogeneous disease entities. Among CAM entities, anti-TIF1-γ-Ab(+) CAM has characteristically shown a close temporal association with cancer detection and the histopathologic findings of dC5b-9 and VFs, and CAM with NAM is a subset of anti-TIF1-γ-Ab(-) CAM.

Chronic Myopathy Associated With Anti-Signal Recognition Particle Antibodies Can Be Misdiagnosed As Facioscapulohumeral Muscular Dystrophy

OBJECTIVES

To report cases of chronic autoimmune necrotizing myopathy with anti-signal recognition particle antibodies (anti-SRP myopathy) initially misdiagnosed as muscular dystrophy, in particular, facioscapulohumeral muscular dystrophy (FSHD).

METHODS

Medical records of patients with anti-SRP myopathy in our institution were retrospectively reviewed.

RESULTS

All 6 patients were initially diagnosed with muscular dystrophy because of the long-term clinical course and lack of inflammation on biopsy; 5 were diagnosed with FSHD based on a winged scapula. However, the following features suggested an alternative diagnosis, leading to anti-SRP antibody measurement: (1) lack of family history, (2) lack of facial involvement and asymmetry, (3) prominent dysphagia, and (4) profuse spontaneous activities on needle electromyography. All patients showed improvement with immunomodulating therapy.

CONCLUSIONS

Anti-SRP antibody measurement should be considered in patients diagnosed with FSHD if they present with diagnostic hallmarks of anti-SRP myopathy listed above, to avoid oversight of this potentially treatable disorder.

Sporadic late-onset nemaline myopathy as a rare cause of slowly progressive muscle weakness with young adult onset

INTRODUCTION

Sporadic late-onset nemaline myopathy (SLONM) is a rare intractable acquired myopathy characterized by progressive muscle weakness and atrophy, usually with middle to late adult onset. Autologous peripheral blood stem cell transplantation (auto-PBSCT) has been reported to be a promising treatment for SLONM.

METHODS

In this study we performed clinical characterization, muscle histopathological analysis, and muscle power monitoring after auto-PBSCT in a 27-year-old HIV-negative man with monoclonal gammopathy.

RESULTS

He showed improved muscle strength after treatment with high-dose melphalan and auto-PBSCT.

CONCLUSIONS

Considering the recent reports of successful treatment of SLONM, early and correct diagnosis of this condition in association with monoclonal gammopathy is important. SLONM should be added to the list of diseases to consider in the differential diagnosis of progressive muscle weakness with young adult onset.

Memory impairment following right cerebellar infarction: a case study

We reported a patient with a right cerebellar infarction who showed anterograde amnesia. Cognitive dysfunction caused by cerebellar lesions was called cerebellar cognitive affective syndrome, and deactivation of the contralateral prefrontal cortex function due to disconnections of cerebello-cerebral fiber tracts have been hypothesized as mechanism underlying the syndrome. The episodic memory impairment, however, could not be supported by the same mechanism because the prefrontal lesions cannot cause amnesia syndrome. The feature of the impairment of our patient was similar to that of diencephalic amnesia, and a single photon emission computed tomography study showed a relative hypoperfusion in the right cerebellar hemisphere and left anterior thalamus. We considered that the memory deficit was caused by the dysfunction of the thalamus, which is a relay center of the cerebello-cerebral connectivity network.

[Vertebral artery dissection due to the C6 transverse process and laryngeal cartilage associated with vertebral artery anomaly]

A 52-year-old woman complained of the sudden onset of a left temporal headache, left neck stiffness and dizziness. Brain magnetic resonance imaging showed a high-intensity lesion in the right medial medulla. Dynamic cerebral angiography revealed vertebral artery dissection and compression at the C6 level due to a transverse process at the C6 level associated with rightward head rotation. Removal of bone and decompression of the vertebral artery were performed from the C5 to C6 levels. Intraoperasively, obstruction of blood flow due to a laryngeal cartilage that rotated with the passive rotation of the patient's head to the right was found. To the best of our knowledge this is the first reported case of vertebral artery occlusion due to a laryngeal cartilage associated with head rotation.

Increased gene dosage of myelin protein zero causes Charcot-Marie-Tooth disease

OBJECTIVE

On the basis of the hypothesis that copy number mutations of the genes encoding myelin compact proteins are responsible for myelin disorders in humans, we have explored the possibility of copy number mutations in patients with Charcot-Marie-Tooth disease (CMT) whose responsible genes remain undefined.

METHODS

A family with 6 affected members in 3 consecutive generations, presenting with motor and sensory demyelinating polyneuropathy, was investigated. Characteristic clinical features in this pedigree include Adie pupils and substantial intrafamilial variability in the age at onset, electrophysiological findings, and clinical severity. Nucleotide sequence analyses of PMP22, MPZ, or GJB1 and gene dosage study of PMP22 did not reveal causative mutations. Hence, we applied a custom-designed array for comparative genomic hybridization (CGH) analysis to conduct a comprehensive screening of copy number mutations involving any of the known causative genes for CMT other than PMP22.

RESULTS

The array CGH analyses revealed increased gene dosage involving the whole MPZ, and the flanking genes of SDHC and C1orf192. The gene dosage is estimated to be 5 copies. This mutation showed complete cosegregation with the disease phenotype in this pedigree.

INTERPRETATION

The increased gene dosage of MPZ and increased expression level of MPZ mRNA emphasize the important role of the dosage of the MPZ protein in the functional integrity of peripheral nerve myelin in humans, and provide a new insight into the pathogenic mechanisms underlying CMT.