AbstractThe clinical course of Graves' disease is described in an 8 year old girl with high thyroid‐stimulating immunogloblin (TSI) and thyrotropin‐binding inhibition immunoglobulin (TBII) titers, 6,421% and 87.8%, respectively. She had three cycles of alternating hyper‐ and hypothyroidism during two years of observation with or without antithyroid medication or thyroxine replacement. She also developed a propylthiouracil‐induced lupus‐like syndrome with a positive antinuclear antibody. Although a causal relationship between elevated TSI and TBII titres and hyper‐hypothyroidism was not established, the coexistence of high TSI and TBII titres requires close observation for the proper treatment of th