Dados do Trabalho

Título

DERMATOMYOSITIS WITHOUT CHANGES IN MUSCLE ENZYMES: A CASE REPORT

Apresentação do caso único

A 5-year-old boy is undergoing a course of global and progressive loss of strength since July, 2023. He has been presenting difficulty in sitting and squatting without support, climbing steps stairs and frequent falls. There is a report of adequate neuropsychomotor development, except for a delay in the beginning of speech. Parents are not consanguineous and there are no reports of diseases in family. The patient has a history of asthma and his mother reports that there is an improvement in his weakness with the use of corticosteroids at times when he was in crisis of this pathology. In the initial investigation, muscle enzymes were within normal limits, but there were changes on physical examination, with decreased strength mainly proximal segments and neck flexion. Skin lesions similar to heliotrope and on hands similar to Gottron's papules were noted. Nuclear magnetic resonance of the lower limbs was performed with the presence of edema in both limbs and an x- ray of the left lower limbs showed calcinosis. Electroneuromyography was normal. An antibody panel for myositis was performed with positive results for the NXP2 autoantibody, confirming the diagnosis of Dermatomyositis.

Discussão

Dermatomyositis is the most common form of myositis, even though it is considered a rare disease. Its diagnosis can be made using the criteria of EULAR score, with alterations in muscle enzymes being common, such as increased creatine phosphokinase, transaminases, erythrocyte sedimentation value, accompanied by clinical characteristics suggestive of decreased strength mainly in proximal segments, presence of heliotrope and gottron papules or gottron sign. Confirmation can be made taking into account the changes above, and changes in the muscle biopsy may be associated. The NXP2 autoantibody is related with distal weakness, increase in calcinosis, and a greater predisposition to neoplastic diseases, requiring constant monitoring.

Comentários finais

Dermatomyositis should be suspected even in the absence of changes in muscle enzymes or electroneuromyographic changes, taking into account mainly the patient's clinical condition and carrying out more specific tests.

Referências

HUTCHINSON, Clare. Juvenile dermatomyositis and other idiopathic inflammatory myopathies: Diagnosis. 2024. Disponível em: https://www.uptodate.com/contents/juvenile-dermatomyositis-and-other-idiopathic-inflammatory-myopathies-diagnosis?source=autocomplete&index=0~3&search=dermato. Acesso em: 06 ago. 2024.
HUTCHINSON, Clare. Juvenile dermatomyositis and other idiopathic inflammatory myopathies: Epidemiology, pathogenesis, and clinical manifestations. 2024. Disponível em: https://www.uptodate.com/contents/juvenile-dermatomyositis-and-other-idiopathic-inflammatory-myopathies-epidemiology-pathogenesis-and-clinical-manifestations?search=dermatomiosite%20juvenil&source=search_result&selectedTitle=1%7E36&usage_type=default&display_rank=1. Acesso em: 06 ago. 2024.
FHC, Souza. MIOPATIAS AUTOIMUNES SISTÊMICAS: papel diagnóstico dos anticorpos miosite-específicos ou miosite-relacionados. PAPEL DIAGNÓSTICO DOS ANTICORPOS MIOSITE-ESPECÍFICOS OU MIOSITE-RELACIONADOS. 2018. Disponível em: https://amb.org.br/wp-content/uploads/2021/09/MIOPATIAS-AUTOIMUNES-SISTEMICAS-PAPEL-DIAGNOSTICO-DOS-ANTICORPOS-MIOSITE-ESPECIFICOS-FINAL-2018.pdf. Acesso em: 06 ago. 2024.

Palavras Chave

Dermatomyositis; Autoantibodies; Proximal weakness