The Inflammatory Myopathies (eBook)

Preface 5
Contents 6
Contributors 8
Chapter 1 Evaluation of the Patient 11
Introduction 11
Clinical Findings 12
Pulmonary Disorders 15
Cardiac Manifestations 15
Vascular Findings 16
Gastrointestinal Involvement 16
Laboratory Assays 16
References 21
Chapter 2 Classification of Idiopathic Inflammatory Myopathies 24
Defining the Idiopathic Inflammatory Myopathies 25
Clinicopathologic Classifications 26
Serologic Classifications 29
Environmentally Associated Myositis 30
Genetic Classifications 32
References 35
Chapter 3 The Inflammatory Milieu: Cells and Cytokines 38
Introduction 39
T Cells 40
T Cells in Myositis 40
Dendritic Cells 43
Dendritic Cells in Myositis 44
B Cells 46
B Cells in Myositis 46
Macrophages 47
Macrophages in Myositis 47
Natural Killer T Cells 47
NK Cells in Myositis 48
Muscle and Endothelial Cell Involvement 48
Cytokines and Chemokines 50
Type I Interferons 50
Tumor Necrosis Factor- a 53
Interleukin 1 54
Conclusion 55
References 55
Chapter 4 Juvenile Dermatomyositis: An Update on Clinical and Laboratory Findings 63
Historical Background and Overview 64
Demographic Data 64
Risk Factors for JDM: Overview 65
Ultraviolet Light as an Environmental Risk Factor 66
Infection as an Environmental Risk Factor 66
Seasonality: Associations with Disease Onset and Birth of Children with JDM 68
Diagnostic Criteria for Juvenile Dermatomyositis 69
Physical Signs of Children with JDM at Diagnosis 72
Muscle Histopathology in the Pediatric Inflammatory Myopathies 74
Type 1 Interferon-Induced Genetic Response in Muscle and Blood from Children with JDM 75
Commonalities and Differences Between Children with JDM and SLE 75
Impact of Duration of Untreated Disease at Diagnosis on Physical and Laboratory Findings as Well as Gene Expression Profile Data 76
Chronic Inflammation and Gene Expression Profile Data 79
Diagnostic Evaluation 81
Differential Diagnosis of JDM 81
Therapy of JDM 83
Outcomes of JDM 86
Summary and Hopes for the Future 87
References 87
Chapter 5 Inclusion Body Myositis 95
Introduction 95
Clinical Findings 96
Muscle Biopsy 97
Pathogenesis 98
Summary of Theories of Pathogenesis 101
Therapy 101
Hereditary Inclusion Body Myopathy 101
References 102
Chapter 6 The Role of Muscle Biopsy in the Diagnosis of Inflammatory Myopathy 103
Classification of Idiopathic Inflammatory Myopathies 103
Histopathology of Inflammatory Myopathy 104
Inclusion Body Myositis 107
References 117
Chapter 7 Electromyography 119
Introduction 119
Approach to the Patient with Weakness 120
Physiologic Basis of Electrodiagnostic Studies 120
Standard Electrodiagnostic Studies 123
Technical Issues 127
Special Electrodiagnostic Studies 128
Inflammatory Myopathies 129
Polymyositis and Dermatomyositis 131
Inclusion Body Myositis 132
Conclusion 132
References 133
Chapter 8 Magnetic Resonance Imaging of Myopathies and Myositis 134
Introduction 134
MRI Technical Considerations 135
Dermatomyositis and Polymyositis 141
Inclusion Body Myositis 143
Focal Myositis 144
Pyomyositis and Muscle Infarction 144
Trauma and Myositis Ossificans 148
Miscellaneous (Compartment Syndrome, Muscle Denervation) 150
Conclusions 152
References 152
Chapter 9 Ultrasound in the Evaluation of the Inflammatory Myopathies 154
Introduction 154
Technical Factors and New Developments 155
Normal Sonographic Appearances 159
Muscle Edema Pattern 160
Muscle Atrophy 162
Calcification 166
Specific Disease Patterns 166
Conclusion 169
References 169
Chapter 10 Serological Findings 172
Overview 173
Established MSAs 179
Overlap Antibodies 186
New DM Autoantibodies 188
Significance of the Myositis Autoantibodies 190
References 191
Chapter 11 Antisynthetase Syndrome 197
Introduction 197
Antisynthetase Autoantibodies and Their Targets 198
The Role of Jo-1 Autoantibodies in Pathogenesis 199
Clinical Manifestations and Prognosis 202
Prognosis and Treatment 207
Conclusion 208
References 210
Chapter 12 Pulmonary Manifestations of Inflammatory Myopathy 213
Introduction 214
Interstitial Lung Disease 215
Prognosis 221
Treatment 222
Secondary Pulmonary Complications 223
Conclusion 224
References 224
Chapter 13 Dermatological Manifestations of Dermatomyositis 228
Rash 228
Histology 231
Calcinosis 232
Therapy 234
References 235
Chapter 14 The Differential Diagnosis of Inflammatory Myopathy 236
Introduction 236
Metabolic Myopathies 243
Mitochondrial Myopathies 245
Drug- and Toxin-Induced Myopathy 246
Endocrine Myopathies 247
Muscle Disorders Associated with Electrolyte Disturbance 248
Myopathy Associated with Collagen Vascular Disease 250
Cancer and Myopathy 251
Infiltrative Myopathy 251
Nutritional Deficiency and Myopathy 252
Motor Neuron Disease 252
Conclusion 252
References 253
Chapter 15 Outcomes and Assessment for Inflammatory Muscle Disease 257
Introduction 257
Core Set Measures to Assess Disease Activity 258
Ancillary Measures to Assess Disease Activity 269
Assessment of Disease Damage 272
Patient Self-Assessment: Health-Related Quality of Life 273
Conclusions 275
References 275
Chapter 16 Muscle Strength and Exercise in Patients with Inflammatory Myopathies 281
Muscle Impairment in Patients with Adult Polymyositis and Dermatomyositis 282
Muscle Impairment in Patients with Inclusion Body Myositis 283
Exercise in a Historical Perspective 283
Exercise in Adult Polymyositis and Dermatomyositis 284
Molecular Effects of Exercise in Polymyositis or Dermatomyositis 300
Exercise in Inclusion Body Myositis 303
Exercise in Juvenile Dermatomyositis 304
Exercise Recommendations 306
Conclusion 307
References 307
Chapter 17 The Risk of Malignancy in Patients with Dermatomyositis and Polymyositis 311
Epidemiology 312
Types of Malignancies Associated with DM and PM 314
Clinical Course of Malignancy and Myositis 315
Risk Factors for Malignancy in DM and PM 316
Evaluation for Malignancy 317
Pathogenesis 318
Conclusion 319
References 319
Chapter 18 Treatment 323
Introduction 323
General Approach to Therapy 325
Corticosteroids 325
Immunosuppressive Agents and Other Treatments 327
Methotrexate and Azathioprine 328
Intravenous Immunoglobulin 329
Cyclosporine 330
Mycophenolate Mofetil 330
Tacrolimus 331
Rituximab 331
Tumor Necrosis Factor Alpha Blockade 332
Plasma Exchange 333
References 334
Index 337