42 - Dermatomiosite

Question 1

Síndrome anti-sintetase?

Answer 1

• auto-Acs anti-sintetase,
• febre,
• poliartrite erosiva,
• “mãos de mecânico”,
• fenómeno de Raynaud,
• doença pulmonar intersticial.

Question 2

Onde se deve fazer a biópsia muscular na dermatomiosite?

Answer 2

It is best for the clinician to request that the surgeon sample triceps muscle rather than the usually biopsied deltoid muscle because the latter is often spared until late in the disease.

Question 3

Diferença da patogénese de polimiosite e dermatomiosite?

Answer 3

Previously, polymyositis was thought to represent the same disease process but limited to the muscles; however, there is now evidence that the pathogenetic mechanisms of polymyositis and dermatomyositis differ significantly. In polymyositis, clonally expanded, autoreactive CD8+ T cells invade myocytes expressing MHC class I antigens and cause necrosis via the perforin pathway. In contrast, data support that autoantigens activate a humoral immune process in dermatomyositis, in which complement is deposited in capillaries causing capillary necrosis and ischemia.

Question 4

Doentes com DM juvenil têm risco de neoplasia associada?

Answer 4

Patients with juvenile dermatomyositis do not have an increased risk of malignancy, but do have an increased incidence of calcinosis cutis and associated small vessel vasculitis.

Question 5

Definição de DM hipomiopática?

Answer 5

Hypomyopathic dermatomyositis: no muscle weakness clinically but characteristic laboratory or radiographic abnormalities.

Question 6

Manifestações cutâneas comuns de DM?

Answer 6

• Heliotrope sign,
• Eyelid edema,
• Gottron papules,
• Gottron sign,
• Photodistributed poikiloderma (includes facial erythema, shawl sign, V-neck sign),
• Scalp poikiloderma and scaling,
• Non-scarring alopecia,
• Nail-fold changes (includes ragged cuticles, cuticular hypertrophy, nail-fold telangiectasias*),
• Holster sign (poikiloderma of the lateral thighs),
• Psoriasiform lesions,
• Calcinosis cutis (especially in juvenile dermatomyositis).

Question 7

Manifestações cutâneas incomuns de DM?

Answer 7

~Cutaneous erosions or ulcerations,
~Flagellate erythema,
~Tender palmar papules,
~Hyperkeratotic palmar papules,
~Exfoliative erythroderma,
~Cutaneous eruption that mimics PRP (Wong variant),
~Vesiculobullous lesions,
~Pustular eruption of the elbows and knees,
~Ovoid palatal patch,
~Gingival telangiectasias,
~Panniculitis,
~Lipoatrophy (especially in juvenile dermatomyositis),
~Small vessel vasculitis (especially in juvenile dermatomyositis).

Question 8

DD de DM?

Answer 8

1-LE sistémico,
2-Psoríase,
3-DC airbone ou alérgica,
4-Toxidermia fotodistribuída,
5-Linfoma cutâneo células T,
6-Dermatite atópica,
7-Esclerose sistémica,
8-Triquinose,
9-Reticulohistiocitose multicêntrica forma fotodistribuída.

Question 9

Complicações da DM juvenil?

Answer 9

Lipodystrophy and metabolic abnormalities, including hypertriglyceridemia and insulin resistance, have become increasingly recognized as potential complications of juvenile dermatomyositis.