Poly myositis and dermatomyositis Are acquired . chronic , inflammatory muscle condition of unknown cause -Age : most cases are in 5th and 6th decades of life. -Incidence:0.5 per 100,000 population Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Polymyositis (PM) and dermatomyositis (DM) -adult polymyositis -adult dermatomyositis -adult polymyositis, dermatomyositis with malignancies -PM/DM in association with other connective tissue diseases -childhood DM. -inclusion body myositis Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

-Mascular weakness is the dominant feature of myositis syndromes -Symmetryical -Proximal muscle of extremities,trunk and neck Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

-Lower extremities characterized by .An inability to climb stairs .To arise from low seat .Walking may be limited and gait may become poorly coordinated and waddling -Upper extremities .Limits lifting .Handing up clothes and combing the hair -Weakness of the anterior neck flexor muscles interferes with lifting the head from the supine position and arising from bed become difficult Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Adult polymysitis (PM) - Women: men 3:1 The onset can be insidious, over month’s, but can be acute Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

-Malaise- weight loss and fever can develop during the acute phase -The major feature of PM is proximal muscle weakness which is progressive -There is wasting of the shoulder and pelvic girdle muscles with weakness -Pain and tenderness are uncommon -Patients have difficulty squatting going upstairs, raising from a chair raising their hands above the head and holding their head up. Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

-Interstitial lung fibrosis -Arthrlgia 50% -Raynaud’s phenomenon -Involvement of pharyngeal, laryngeal and respiratory muscles can lead to dysphagia , dysphonia and respiratory failure. -Interstitial lung fibrosis -Arthrlgia 50% -Raynaud’s phenomenon -cardiac abnormalities (heart block ,myocarditis,congestive heart failure) Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Adult dermatomyositis -more in women -heliotrope rash and perorbital oedema -gottron rash -ulcerative vascuilitis -subcutaneous calcinosis 25% Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: heliotrope rash The face of this patient demonstrates bilateral heliotrope lids, mainly involving the upper lids with mild involvement of the left lower lid. Erythema is also present over both malar areas and cheeks. #9109010 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: diffuse facial erythema Diffuse, patchy erythema over the forehead, bridge of the nose, malar areas, and chin is present in this patient. This type of rash, which is frequently photosensitive, is commonly seen in patients with dermatomyositis. #9109020 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: rash, chest This woman has acute-onset dermatomyositis. An erythematous eruption is prominent in a mantle distribution over light-exposed areas. Telangiectasias are present. Marked inflammatory changes have caused a breakdown in the skin in several areas. Not shown are similar involvement of the face and a typical heliotrope discoloration around the eyes. #9109090 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: edema and rash, hand This child's hand shows the skin changes of dermatomyositis. Erythematous flat papules may appear over metacarpophalangeal and proximal interphalangeal joints. The lesions are symmetric and overlie the small joints of the hand. A diffuse puffiness of the hand is present. #9109030 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: erythematous lesions, hands Erythematous and slightly scaly lesions are present over the metacarpophalangeal joints of both hands. #9109040 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyosistis: rash, hands Dermatomyositis: rash, hands Typical late cutaneous involvement is seen on the extensor aspect of the joints. The lesions are reddish-white, shiny, slightly scaly, and atrophic. #9109050 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: “mechanic’s hands” Cracking of the finger pad skin, commonly involving the first, second, and third fingers, is demonstrated in this patient with dermatomyositis. Miller FW. Myositis-specific autoantibodies: touchstones for understanding the inflammatory myopathies. JAMA 1993;270:1846-1849. #9109060 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyosistis: periungual involvement Dermatomyositis: periungual involvement Abnormally prominent nailfold capillaries and hemorrhage are present in a patient with dermatomyositis. These vascular changes are essentially indistinguishable from those of systemic lupus erythematosus and scleroderma. #9109070 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: rash, knees A typical scaly erythematous rash involves the extensor surfaces of both knees in this child with dermatomyositis. A violaceous discoloration can also be observed in these lesions. The skin of the lower legs is dark, slightly reddened, and thickened, which indicates more widespread involvement. #9109100 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: subcutaneous calcification, knees This child with dermatomyositis has moderately severe calcinosis of the soft tissues around the knees. These calcific nodules are discrete, in contrast to the "plate-like" sheets occasionally seen. The nodule of calcium on the left knee is about to erupt and may become infected. The reflecting points of light on the medial aspects of both knees represent calcium deposits that have already extruded. #9109110 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Dermatomyositis: calcinosis, thigh (radiograph) There is extensive calcification in several planes including subcutaneous tissue, fascia, and muscle. In some instances, the skin may show calcification. In scleroderma the calcification usually would not be within the muscle proper. These calcifications are amorphous, contrasting with the trabecular calcification of myositis ossificans. #9509010 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Associated with malignancies -The associated cancer may not become apparent for 2-3 years. -Recurrent or refractory dermatomyositis should prompt a search for occult malignancy -Lung, ovary, breast, stomach cancer can predate the onset of myositis particularly in males with dematomyositis Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Childhood dermatomyositis -Age : 4-10 years -Subcutaneous calcification maybe widespread and severe -Recurrent abdominal pain due to vascuilitis Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Inclusion Body Myositis General Features Most common acquired muscle disease over the age of 50 Prevalence of 5-10/million Affects men > women at 2-3:1 Average time from symptom onset to diagnosis is ~ 6 years Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Clinical Features of IBM • Consider IBM when confronted with refractory polymyositis patient • Insidious onset of painless muscle weakness with slow progression • Tendency to distal (away from the trunk muscles) and asymmetric muscle involvement (“foot drop”) • Difficulty swallowing • Characteristic pattern of muscle atrophy (forearm flexors, muscles of hands, thigh) Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Inclusion body myositis Males affected more than females Age of onset usually greater than 50 Slowly progressive Distal and asymmetric muscle weakness Myopathic and neuropathic changes on EMG Mononuclear cell infiltrates and vacuoles containing amyloid on muscle biopsy Responds poorly to corticosteroids Inclusion body myositis #0904013 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Polymyositis: differential diagnosis Polymyositis and dermatomyositis Hypothyroidism Drug-induced myopathies Corticosteroids, colchicine, HMG-CoA reductase inhibitors, zidovudine, hydroxychloroquine, alcohol Infections Viral, toxoplasmosis, trichinosis, bacterial pyomyositis Connective tissue disorders Lupus, scleroderma, MCTD Systemic vasculitis PAN, Wegener’s granulomatosis Polymyositis: differential diagnosis #4209030 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Polymyositis: differential diagnosis, cont’d Metabolic myopathies Disorders of carbohydrate and lipid metabolism Electrolyte disturbances Hypernatremia, hyponatremia, hypokalemia, hypophosphatemia, hypocalcemia Inclusion body myositis Sarcoid myopathy Amyloid myopathy Neurologic disorders Myasthenia gravis, motor neuron disease, muscular dystrophy Polymyositis: differential diagnosis, cont’d #4209040 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Neurological disease -Asymmetrical weakness -distal extremety inovlvement -altered sesorium or abnormal cranialnerve function -myopathies cause proximal and symmetrical weakness except (IBM, Mitochondrial myopathies, antiSRP antibody) Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

-Limb-girdle dystrophy positive family history upper and lower extremity proximal muscle weakness may begin in the first through third decades of life. muscle wasting -Duchenn`es musclar dystrophy The age of 5 years Muscle weakness and wasting Hyperlordotic gait Psuedo hypertrophy of the calf muscle Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

-Becker`s muscular dystrophy Similar but milder Patient able to walk beyond the age 16 -Facioscapulo humeral Autosomal dominant Weakness begin in the facial muscle Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Don’t Forget Patients with hypothyroidism can present with diffuse and nonspecific arthralgias and myalgias. CKs may be elevated Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved. 11

Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Think About Toxic Drug Reactions That Can Cause Musculoskeletal Pain Hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitor Zidovudine (AZT) Ethanol Clofibrate Cyclosporin A Penicillamine Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved. 12

Soft-Tissue Pain Syndromes: Fibromyalgia Widespread musculoskeletal pain Decreased pain threshold and tolerance May have tenderness in specific regions (tender points) Associated fatigue, sleep, somatic complaints No objective inflammation seen on physical examination Normal laboratory findings Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved. 15

Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Common Causes of Proximal Muscle Weakness With Elevated CK Inflammatory myositis Noninflammatory myopathies Hypothyroidism Hypokalemia Alcoholism Drugs AZT HMG-CoA reductase inhibitors (the “statins”) Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved. 26

Myositis-specific antibodies ANTIBODY DISEASE ASSOCIATION PREVALENCE Anti-tRNA synthetases (Jo-1) Dermatomyositis, interstitial lung disease, “mechanic’s hands” 20% Anti-SRP (signal recognition protein) African-American women, poor prognosis Rare Anti-Mi-2 Older women, “shawl sign,” good prognosis 5% PM/SCL Polymyositis/scleroderma overlap Myositis-specific antibodies Love LA, Leff RL, Fraser DD, et al. A new approach to the classification of idiopathic inflammatory myopathy: Myositis specific antibodies define useful homogeneous patient groups. Medicine 1991; 70:360. #0904014 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

-screening for malignancy -EMG -Needle muscle biopsy -MRI -screening for malignancy Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Proposed diagnostic criteria for polymyositis and dermatomyositis PM diagnosed as definite with 4 out of 5 of the below criteria or probable with 3 out of 5 DM diagnosed as definite with rash plus 3 out of 4 of the below criteria or probable with rash plus 2 out of 4 criteria Symmetric proximal muscle weakness Elevated muscle enzymes (CPK, aldolase, transaminases, LDH) Myopathic EMG abnormalities Typical changes on muscle biopsy Typical rash of dermatomyositis Proposed diagnostic criteria for polymyositis and dermatomyositis Bohan A, Peter JB. Polymyositis and dermatomyositis (first of two parts). N Engl J Med 1975;292:344-347. #9209010 Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.

Polymyositis/Dermatomyositis -Therapy Prednisone 1–2 mg/kg, as initial therapy Methotrexate or azathioprine is often added Intravenous immunoglobulin in rapidly progressive or refractory cases Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved. 29

Treatment Options in Myositis Corticosteroids (prednisone) Immunosuppressive agents Methotrexate cyclosporine Azathioprine cyclophosphamide leflunomide chlorambucil mycophenolate mofetil IVIg Anti-TNF agents (etanercept, infliximab) “Biologic” response modifiers rituximab Oxandrolone (IBM) Other (stem cell transplant) Copyright © 1972-2004 American College of Rheumatology Slide Collection. All rights reserved.