IgG2 Deficiency in Young Children Treated With Continuous Ambulatory Peritoneal Dialysis (CAPD)

Blood samples were taken during routine control visits. Concentrations of serum IgA, IgG, and IgM were measured by laser immunonephelometry with a DISC 120 Nephelometer (Hyland, Nivelles, Belgium) using monospecific antisera against human IgA, IgG, and IgM (Dako, Glostrup, Denmark). Detection limits with this method are 2 U/mL for IgA (1 U/mL = 18.7 mg/L), and 4 U/mL for IgG (1 U/mL = 89.3 mg/L) and IgM (1 U/mL = 9.8 mg/L). Levels of the IgG subclasses in serum were determined by radial immunodiffusion using monospecific antisera to the 4 IgG subclasses (Centraal Laboratorium van de Bloedtransfusiedienst, Amsterdam, The Netherlands). Detection limits of the subclasses are 10 % of the standard serum. Normal concentrations are derived from a large study of Swedish children (3)