Here we report the case of a 20-year-old female patient previously diagnosed with Hashimoto's
thyroiditis and overt
hypothyroidism, and who had been taking synthetic
thyroxine (100 microg/day) for eight months. She experienced intermittent
dizziness and generalized weakness, and was diagnosed as having severe
autoimmune hemolytic anemia (AIHA). We prescribed
prednisolone treatment and continued synthetic
thyroxine administration. Two years and five months later, she developed
idiopathic thrombocytopenic purpura (
ITP) and was diagnosed with
Evans' syndrome. Thereafter, laparoscopic
splenectomy was performed because her
autoimmune hemolytic anemia was refractory and dependent on
steroid therapy. The HLA genotypes of the patient were
HLA-A*020101/A* 2602,
HLA-B*270502/B*5401,
HLA-Cw*0102/Cw*020202,
HLA-DRB1*0404/DRB1*0405, and
HLA-DQB1*0302/DQ B1*0401. Hashimoto's
thyroiditis is often associated with other nonendocrine
autoimmune diseases, and antithyroid
antibodies are frequently observed in
Evans' syndrome (coexistence of AIHA and
ITP). However, there is no report of
Evans' syndrome developing in patients with overt
hypothyroidism and Hashimoto's
thyroiditis. This case suggests that three
autoimmune diseases (AIHA,
ITP, and Hashimoto's
thyroiditis) might share a common immunogenetic pathway in pathogenesis.