Table 1 Preferred testing in patients with probable juvenile dermatomyositis

Laboratory diagnostics

> 75% of participants^a

Erythrocyte sedimentation rate, GOT/AST, GPT/ALT, CK, LDH, ANA, CBC with differential count, CRP, BUN/creatinine, IgG/IgA/IgM

50–75% of participants^a

C3 and C4, myositis blot, ENA panel, vWF antigen, total protein, ferritin, thyrotropin, uric acid, aldolase, rheumatoid factor and CCP antibody

< 50% of participants^a

Albumin, 25-OH vitamin D, extended myositis blot (including anti-NXP2, -TIF1gamma, −MDA5), serologic testing for certain infections, cardiac-specific troponin, SPEP, NT pro-BNP, fecal calprotectin, serum neopterin, 1,25 (OH)2 vitamin D, tTG-IgA, lymphocyte subpopulations, stool occult blood

Apparatus-based diagnostics or interventions

> 75% of participants^a

ECG, pulmonary function testing, echocardiography, muscle MRI

50–75% of participants^a

muscle ultrasound, nailfold capillaroscopy, abdominal ultrasound

< 50% of participants^a

Chest radiograph, EMG, muscle biopsy, swallow study, chest CT

Juvenile dermatomyositis-specific clinical scores or subspecialty consultations

> 75% of participants^a

N/A

50–75% of participants^a

Childhood myositis assessment scale (CMAS)

< 50% of participants^a

Disease activity score, dermatology consultation, manual muscle testing (MMT)-8, neurology consultation