Juvenile idiopathic polyarticular arthritis and IgA deficiency in the 22q11 deletion syndrome

• Published in: Journal of rheumatology Vol. 28; no. 10; pp. 2326 - 2334
• Main Authors: DAVIES, Karen, STIEHM, E. Richard, WOO, Patricia, MURRAY, Kevin J
• Format: Journal Article
• Language: English
• Published: Toronto, ON The Journal of Rheumatology 01-10-2001; Journal of Rheumatology Publishing
• Subjects: Adolescent; Adult; Arthritis, Juvenile - epidemiology; Arthritis, Juvenile - genetics; Arthritis, Juvenile - immunology; Biological and medical sciences; Child, Preschool; Chromosomes, Human, Pair 22; Complex syndromes; DiGeorge Syndrome - epidemiology; DiGeorge Syndrome - genetics; DiGeorge Syndrome - immunology; Female; Gene Deletion; Genetic Predisposition to Disease; Haplotypes; Humans; IgA Deficiency - epidemiology; IgA Deficiency - genetics; Male; Medical genetics; Medical sciences; Prevalence; Chromosomal aberration; Immunopathology; IgA; DiGeorge syndrome; Pathogenesis; Diseases of the osteoarticular system; Clinical form; Juvenile rheumatoid arthritis; Chromosome; Velocardiofacial syndrome; Inflammatory joint disease; Genetic disease; Case study; Symptomatology; Chronic; Association; Malformation; Parathyroid diseases; Deletion; Abnormal chromosome; Genetics; Complex syndrome
• ISSN: 0315-162X; 1499-2752

Five patients with the 22q11 deletion syndrome (velocardiofacial syndrome) developed chronic inflammatory polyarticular arthritis.
These new cases add to 8 previously reported and confirm the association. The arthritis in all cases was moderate to severe,
but at least partially responsive to methotrexate and/or corticosteroids, and was clinically indistinguishable from juvenile
idiopathic arthritis (JIA). Analysis of the total 13 patients indicates that 2 are rheumatoid factor positive, 6 are antinuclear
antibody positive, 5 have subtle T cell deficiencies, and 6 have hypergammaglobulinemia. Of particular interest is the occurrence
of IgA deficiency in 4 patients, including 2 from our own series. Although IgA deficiency is seen in both JIA (2-4%) and 22q11
deletion syndrome (2-4%), the prevalence of low IgA in this series (31%) is much greater than expected. This phenomenon and
the true association of inflammatory arthritis and a chromosome deletion disorder provides further evidence of important genetic
factors in the pathogenesis of JIA.