Pulmonary fibrosis and myositis in a child with anti-Jo-1 antibody.

This is the first report of a child with anti-Jo-1 antibody. At 10, she had a chronic cough, wheezing, dyspnea on exertion, a combined obstructive and restrictive ventilatory defect, and a decreased diffusion capacity compatible with alveolar fibrosis (lung biopsy). By age 12, she developed arthralgias, malar rash, frontal alopecia, Raynaud's phenomenon, and was seropositive for antinuclear antibodies, (SSA)Ro, Jo-1 and rheumatoid factor. At 16, symptomatic inflammatory myositis (elevated creatinine kinase, muscle biopsy) was documented with persistent anti-Jo-1. Her pulmonary symptoms have progressed despite appropriate therapy. Although her digits have become sausage shaped with swan neck deformities, joint pain is not frequent.