Mixed connective tissue disease in children and adolescents.

Since the recognition of mixed connective tissue disease in 1972, a small number of pediatric and adolescent patients with this disorder have been described in detail. Four additional patients, two male and two female, are reported in this study. Age range at onset of symptoms was 11 to 18 years. All had arthritis or arthralgia, cervical lymphadenopathy, and hypergammaglobulinemia. Skin rashes and restrictive pulmonary disease were present in three; Raynaud phenomenon, skeletal myopathy, elevation of serum IgE, and neurologic abnormalities were present in two of the four patients. One patient had cardiomyopathy which was progressive over three years. Renal function was normal in all four patients. Most manifestations of the disease in these patients appeared to respond to variable doses of corticosteroids. A review of 234 reported patients with mixed connective tissue disease, including 50 pediatric patients, suggests a higher prevalence of renal and cardiac disease in affected children and adolescents. A multicenter cooperative study of patients with mixed connective tissue disease is strongly recommended to determine the natural history and the effects of therapeutic interventions in this disease.