"Gottron sign" seen in
High-Yield Explanation
(Dermatomyositis) (760-CMDT-10, 2696-H 17th)* "Gottron sign" - scaly patches over of the dorsum of PIP and MCP joints are highly suggestive of dermatomyositisDERMATOMYOSITIS - the characteristic rash is dusky red and may appear in a malar distribution mimicking the classic rash of SLE* Facial erythema beyond the malar distribution is also characteristic of dermatomyositis (Shawl's sign)* Periorbital edema and a purplish (heliotrope) suffusion over the eyelids are typical signs, periungual erythema, dilations of nailbed capillaries* Bilateral proximal muscle weakness*** *** Increased risk of malignancy** - in descending order of frequency are ovarian, lung, pancreatic, stomach, colorectal and NHL)* Biopsy of clinically involved muscle is the only specific diagnostic test*** A pathologic hall mark of dermatomyositis is perifascicular atrophy. In polymyositis - endomysical infiltration of the inflammatory infiltrate**** Various auto antibodies against nuclear antigens (antinuclear antibodies) and cytoplasmic antigens are found in upto 20% of patients with inflammatory myopathies* Glucocorticoids: oral prednisone is the initial treatment of choice* Myositis may also be associated with other connective tissue diseases especially - Scleroderma, lupus, mixed connective tissue disease and Sjogren syndrome, overlap syndrome* Antisvnthetase syndrome - polymyositis and dermatomyositis develops- inflammatory arthritis, Raynaud phenomenon, interstitial lung disease, auto antibodies (eg anti Jo I antibodies)* Most common myositis-specific antibody -anti Jo-I antibody** (ILD)* Anti Mi-2 associated with dermatomyositis* Anti SRP (anti- signal recognition particle) associated with polymyositisPolymyositis can occur as a complication of HIV or HTLV-1 infection and with zidovudine therapy as well**** Anti-endomysial antibody - Celiac sprue*** Anti mitochondrial antibody - Primary biliary cirrhosis*** Anti-smooth muscle antibody - Auto immune hepatitis* Anti centromere antibody - CREST syndrome (limited scleroderma)* Histidyl-t-RNA antibody - Inflammatory myopathy * Anti DNA topoisomerase antibody (Scl-70)- Systemic sclerosis * Antibodies of ribonucleoprotein antigen containing ULRNP- Mixed connective tissue disease * SSb(La)* SSb(La)}Antibodies to ribo nucleoprotein antigen- Sjogren syndrome