|Year : 2016 | Volume
| Issue : 1 | Page : 53-55
Dermatomyositis: A case report
Meenakshi Kalyan1, Shubhangi A Kanitkar1, Anu N Gaikwad1, Harsh Kumar2
1 Department of Medicine, Padmashree Dr. D.Y. Patil Medical College Hospital and Research Centre, Pune, Maharashtra, India
2 Department of Pathology, Padmashree Dr. D.Y. Patil Medical College Hospital and Research Centre, Pune, Maharashtra, India
|Date of Web Publication||4-Mar-2016|
Department of Medicine, Padmashree Dr. D.Y. Patil Medical College Hospital and Research Centre, Pimpri, Pune, Maharashtra
Source of Support: None, Conflict of Interest: None
Dermatomyositis is an idiopathic inflammatory myopathy involving proximal muscle weakness and non-suppurative skeletal muscle inflammation. Classification of dermatomyositis for a definitive diagnosis requires characteristic rash and other criteria, such as proximal muscle weakness and muscle enzyme level elevation. Muscle biopsy is central in establishing the diagnosis. In this article, we report a case of dermatomyositis without coexisting cancer, which is rare.
Keywords: Inflammatory myopathy, creatinine phosphokinase, muscle biopsy
|How to cite this article:|
Kalyan M, Kanitkar SA, Gaikwad AN, Kumar H. Dermatomyositis: A case report. J Mahatma Gandhi Inst Med Sci 2016;21:53-5
| Introduction|| |
Dermatomyositis is an idiopathic inflammatory myopathy.  The average age at diagnosis is 40 years, and almost twice as many women are affected as men, with a prevalence rate of 1 per 100,000 in the general population. The incidence of malignancy is high, especially in the older age groups. Diagnostic criteria include typical cutaneous features, progressive proximal symmetrical muscle weakness, elevated muscle enzymes and abnormal findings from muscle biopsy.  We report a male patient with the features of dermatomyositis.
| Case Report|| |
A 33-year-old male patient presented with myalgia, difficulty in climbing stairs, getting up from squatting position and combing his hair since 3 months. The weakness was bilateral, gradual in onset and progressive to involve the distal muscles of the upper limb. There were no fasciculations. He noticed swelling around both eyes and cheeks with rash on the forehead and malar prominences since 3 months, with aggravation of the rash when exposed to the sun. He also developed similar a rash on both arms. There was no history of fever, dyspnea, dysphagia and use of any medications. On general physical examination, his vitals were normal. Hyper-pigmented maculopapular erythematous rash was seen on the forehead, nose, cheeks [Figure 1] and arms, [Figure 2] with upper eyelids edema. The ear, nose and throat examination was normal. Neurological examination revealed normal higher mental functions and cranial nerves, power of grade 3 at shoulder and elbow joints, grade 4+ in wrist joint, grade 3 at the hip and knee joint and grade 5 at the ankle joint. Tone was normal, all deep tendon reflexes were present and plantars bilaterally flexors. The sensory system was within normal limits. The remainder of the neurological examination was unremarkable. The respiratory, cardiovascular and abdominal systems were normal. Investigations revealed Hb-13.8 gm%, WBC-6200/cumm, P72 L23 E2 M1, platelets-2.5 lakhs/cumm, ESR-75 mm/1 h. Urine analysis, renal function tests and blood glucose were within normal limits. The liver function test showed ALT-218 IU/L (reference: 0-40 IU/L). Creatinine phosphokinase-6459 IU/L (reference: 24-190 IU/l), S. lactate dehydrogenase (LDH)-1308 IU/L (reference: 40-250 IU/L), S. aldolase-11.5 U/L (normal < 7.60 U/L), S. Jo-1 antibody was negative, thyroid function tests were normal and ANA was negative. Chest X-ray, ECG, 2D echocardiography, CT chest, ultrasound abdomen and pelvis were normal. Electromyography (EMG) showed early and complete recruitment with polyphasic and low-amplitude motor unit action potential, suggestive of myopathic process. Muscle biopsy showed skeletal muscle fibers showing scattered degenerative changes. Some were intensely eosinophilic while others showed granularity. There is internalization of nuclei and areas of nuclear fragmentation seen. Perivascular collections of lymphocytes are seen. Blood vessels show endothelial cell swelling consistent with dermatomyositis [Figure 3]. Based on the above findings of proximal muscle weakness, rash, elevated creatinine phosphokinase, S. LDH, aldolase and findings of EMG and muscle biopsy, a diagnosis of dermatomyositis was made. He was put on prednisolone 60 mg once a day with a marked improvement in muscle power in 3 weeks, with fall in the creatinine kinase levels. At present, he is on prednisolone 10 mg/day maintenance therapy.
|Figure 1: Hyperpigmented maculopapular rash seen on the nose and cheeks with upper eyelid edema|
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|Figure 3: Photomicrograph showing injured muscle fiber and inflammatory cells in the endomysium with magnification, ×400|
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| Discussion|| |
Dermatomyositis is identified by a characteristic rash accompanying or, more commonly, preceding muscle weakness. The hallmark cutaneous findings include a heliotrope rash (blue-purple discoloration) on the upper eyelids in many cases associated with edema and an erythematous rash on the face, neck and anterior chest (often in a V sign) or back and shoulders (shawl sign), knees, elbows and malleoli; the rash can be exacerbated after exposure to the sun and is pruritic in some cases. Characteristic is the Gottron rash, a raised violaceous rash or papules at the knuckles, prominent in the metacarpophalangeal and interphalangeal joints. When chronic, the rash becomes scaly with a shiny appearance. Dilated capillary loops at the base of the fingernails with irregular, thickened and distorted cuticles are also characteristic. The lateral and palmar areas of the fingers may become rough with cracked, "dirty" horizontal lines, resembling "mechanics' hands." Rare or uncommon cutaneous manifestations are erythroderma, anasarca, vesicobullous lesions, acquired icthyosis, general and infrapatellar hypertrychosis, follicular papules and hyperkeratosis (Wong type of dermatomyositis), non-scarring alopecia, leukocytoclastic vasculitis, livedo reticularis, panniculitis, mucinous papules and plaques and flagellate erythema.  The weakness can be mild, moderate or severe enough to lead to quadriparesis. Myalgia and muscle tenderness may occur in a small number of patients. Extramuscular manifestations may be present to a varying degree, which include:
The incidence of malignancy is higher in dermatomyositis, especially in the older age groups, which are ovarian cancer, breast cancer, melanoma, colon cancer and non-Hodgkin's lymphoma. Nasopharyngeal cancer is common in the Asian population.  Our patient did not show any evidence of malignancy. Patients with a diagnosis of dermatomyositis were subclassified by disease subtypes. 
- Joint contractures.
- Dysphagia due to the involvement of the oropharyngeal striated muscles and upper esophagus.
- Cardiac disturbances including atrioventricular conduction defects, tachyarrhythmia, myocarditis in patients with acute disease and heart failure commonly related to hypertension from long-term steroid use.
- Pulmonary symptoms are due to weakness of the thoracic muscles or interstitial lung disease, which is common in patients with autoantibodies to tRNA synthetases.
- Subcutaneous calcifications, sometimes extruding on the skin and causing ulcerations and infections.
- General symptoms including fever, malaise, weight loss, arthralgia and Raynaud's phenomenon when associated with another connective tissue disease.
This patient is classified as classic dermatomyositis. Treatment consists of high-dose prednisone, azathioprine, mycophenolate or methotrexate for steroid-sparing effect, IVIg. Our patient responded to prednisolone 60 mg once a day with improvement of muscle power to grade 4+. Dermatomyositis has a better prognosis and responds more favorably to therapy with full functional recovery, often sustained with maintenance therapy. Relapses can occur at any time. The prognosis is worse for patients who are severely affected at presentation, when initial treatment is delayed, and in cases with severe dysphagia or respiratory difficulties.
- Classic dermatomyositis: Hallmark cutaneous manifestations with evidence of proximal muscle weakness occurring within 6 months after onset of skin disease.
- Amyopathic dermatomyositis: Hallmark cutaneous manifestations of dermatomyositis for more than 6 months without clinical or laboratory evidence of myopathy.
- Exclusion criteria: Use of drugs capable of producing hallmark cutaneous changes characteristic of dermatomyositis and use of systemic immunosuppressive agents for more than two consecutive months within the 6 months after skin disease onset.
- Hypomyopathic dermatomyositis: Hallmark cutaneous manifestations without subjective muscle weakness for more than 6 months but with objective evidence of subclinical muscle weakness on further testing (abnormal muscle enzymes, signs of myopathy on electromyography or muscle biopsy).
- Clinically amyopathic dermatomyositis: A term used to describe both amyopathic and hypomyopathic dermatomyositis.
- Clinically amyopathic evolving into classic: Patients with cutaneous dermatomyositis with onset of muscle involvement more than 6 months after onset of clinically significant skin disease.
- Juvenile: Dermatomyositis of any subset occurring in a patient younger than 18 years.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
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[Figure 1], [Figure 2], [Figure 3]