OBJECTIVE: The purpose of this article is to provide readers with an update on the evaluation, diagnosis, and the treatment of juvenile dermatomyositis.
METHODS: A PubMed search was performed in Clinical Queries using the key term "juvenile dermatomyositis" in the search engine. The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to English literature. The information retrieved from the above search was used in the compilation of the present article.
RESULTS: Juvenile dermatomyositis is a chronic autoimmune inflammatory condition characterized by systemic capillary vasculopathy that primarily affects the skin and muscles with possible involvement of other organs. In 2017, the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR) developed diagnostic criteria for juvenile idiopathic inflammatory myopathies and juvenile dermatomyositis. In the absence of muscle biopsies which are infrequently performed in children, scores (in brackets) are assigned to four variables related to muscle weakness, three variables related to skin manifestations, one variable related to other clinical manifestations, and two variables related to laboratory measurements to discriminate idiopathic inflammatory myopathies from non-idiopathic inflammatory myopathies as follows: objective symmetric weakness, usually progressive, of the proximal upper extremities (0.7); objective symmetric weakness, usually progressive, of the proximal lower extremities (0.8); neck flexors relatively weaker than neck extensors (1.9); leg proximal muscles relatively weaker than distal muscles (0.9); heliotrope rash (3.1); Gottron papules (2.1); Gottron sign (3.3); dysphagia or esophageal dysmotility (0.7); the presence of anti-Jo-1 autoantibody (3.9); and elevated serum levels of muscle enzymes (1.3). In the absence of muscle biopsy, a definite diagnosis of idiopathic inflammatory myopathy can be made if the total score is ≥7.5. Patients whose age at onset of symptoms is less than 18 years and who meet the above criteria for idiopathic inflammatory myopathy and have a heliotrope rash, Gottron papules or Gottron sign are deemed to have juvenile dermatomyositis. The mainstay of therapy at the time of diagnosis is a high-dose corticosteroid (oral or intravenous) in combination with methotrexate.
CONCLUSION: For mild to moderate active muscle disease, early aggressive treatment with high-dose oral prednisone alone or in combination with methotrexate is the cornerstone of management. Pulse intravenous methylprednisolone is often preferred to oral prednisone in more severely affected patients, patients who respond poorly to oral prednisone, and those with gastrointestinal vasculopathy. Other steroid-sparing immunosuppressive agents such as cyclosporine and cyclophosphamide are reserved for patients with contraindications or intolerance to methotrexate and for refractory cases, as the use of these agents is associated with more adverse events. Various biological agents have been used in the treatment of juvenile dermatomyositis. Data on their efficacy are limited, and their use in the treatment of juvenile dermatomyositis is considered investigational.
CASE PRESENTATION: A 35 years old man presented with a 5 month history of debilitating painful lower limb and scrotal ulcers. This was associated with polyarthralgia and morning stiffness involving both hands. He also complained of swallowing difficulties. He had unintentional weight loss of 10 kg and fatigue. Physical examination revealed alopecia, multiple cervical lymphadenopathies, bilateral parotid gland enlargement and atrophic glossitis. There was Raynaud's phenomenon noted over both hands and generalised hyper-pigmented fragile skin. Laboratory results disclosed anaemia, leukopenia, hyponatraemia and hypocortisolism. Detailed anaemic workup revealed low serum ferritin and cobalamin level. The autoimmune screen showed positive ANA, anti SmD1, anti SS-A/Ro 52, anti SSA/Ro 60, anti U1-snRNP with low complement levels. Upper gastrointestinal endoscopy with biopsies confirmed atrophic gastritis and duodenitis. Intrinsic factor antibodies and anti-tissue transglutaminase IgA were all negative. Punch biopsies of the leg ulcer showed neutrophilic dermatosis consistent with pyoderma gangrenosum. Based on the clinical findings and positive immunologic studies, he was diagnosed as systemic lupus erythematosus. His general condition improved substantially with commencement of corticosteroids, immunosuppressants and vitamin supplements.
CONCLUSIONS: We report a case of PG as the first manifestation of SLE which was treated successfully with immunosuppressants and vitamin supplements. Our report highlighted the need to consider connective tissue diseases such as SLE in a patient presenting with PG in order for appropriate treatment to be instituted thereby achieving a good outcome.