PROTOCOL OUTLINE:
Blood samples are collected at diagnosis of chromosome 22q11 deletion and assessed for lymphocyte proliferation in response to mitogens phytohemagglutinin, pokeweed mitogen, and concanavalin A (mitogen stimulation analyses). These analyses are repeated at 4 months along with a quantitative analysis of immunoglobulin.
At 8 months, patients are tested for their lymphocytes' ability to respond to antigens (candida, tetanus, and diphtheria). At 1 year, patients have lymphocyte subset, IgG, IgA, and IgM analyses performed. Quantitative evaluations of antibody titers to diphtheria, tetanus, Haemophilus influenza, and hepatitis B are also performed.
Over 1 year of age, all studies are performed if the patient is seen for a single visit.