Fig. 5.

(a,b) Tendency of changes in serum immunoglobulin A (IgA)–anti-tissue transglutaminase (TGA) concentration and avidity during seropostivity. For children with confirmed coeliac disease (C) (a), the autoantibody levels and avidity indices were measured at seroconversion and at diagnosis before introducing a gluten-free diet. Children with transient or fluctuating autoantibodies (b) were analysed at the first and last time-point of seropositivity. Children with fluctuating IgA–TGA positivity are indicated with dashed lines. The children marked with symbols (•) and (○) had fluctuating autoantibodies as determined by enzyme-linked immunosorbent assay (ELISA), but in the fluorometric assay they presented IgA–TGA positivity throughout the follow-up.