Systemic Lupus Erythematosus, Sjögren Syndrome, and Mixed Connective Tissue Disease in Children and Adolescents.

Juvenile systemic lupus erythematosus (jSLE), mixed connective tissue disease (jMCTD), and Sjögren syndrome (jSS) are systemic autoimmune and inflammatory disorders with distinct patterns of organ involvement. All are characterized by autoantibody formation, with antinuclear (ANA) and anti-double-stranded DNA common in jSLE, ANA with high-titer ribonucleoprotein antibody in jMCTD, and Sjögren syndrome A and Sjögren syndrome B antibodies + ANA in jSS. Recognition, monitoring, and management for primary care providers are discussed, focusing on the role of primary physicians in recognizing and helping maintain optimal health in children with these potentially life-threatening diseases.