Graves' hyperthyroidism after postpartum thyroiditis.

Two Caucasian patients are described who had destructive postpartum thyroiditis (PPT) before the subsequent onset of Graves' hyperthyroidism (GH). HLA class II DQ typing in these two subjects identified putative susceptibility alleles previously detected in GH and PPT. Although PPT destructive thyroiditis preceding the development of GH is relatively uncommon, the occurrence of both these syndromes in the same patient suggests the possibility of an etiological role for thyroid antigen release and genetic susceptibility as pathogenic factors in the development of Graves' disease.