Pathologic and immune factors in thyroid disease.

Thyroid glands from 33 children with hyperthyroidism and nine with juvenile lymphocytic thyroiditis were examined histologically and for IgG, IgA, IgM, and C3 by immunofluorescent staining. There was no significant difference between glands with JLT and those with hyperthyroidism in the degree of lymphoid infiltration or lymphoid follicle formation. In thyroiditis there was no correlation between the degree of histologic abnormalities and the presence of immunofluorescent staining for IgG, IgM, or IgA. In hyperthyroidism there was a correlation between the degree of histologic abnormalities and the presence of IgG. In both groups of patients LI and LFF were distinctly more severe in glands positive for C3. Postsurgical hypothyroidism correlated with LI but not with LFF, IgG, or C3.