W. Khovidhunkit et al., Development of overt autoimmune hyperthyroidism in a patient therapeutically immunosuppressed after liver transplantation, THYROID, 10(9), 2000, pp. 829-832
Immunosuppression is a therapeutic maneuver directed at preventing transpla
nt rejection. When applied to autoimmunity, immunosuppression is intended t
o target similar immune processes. We report an unusual case of a 35-year-o
ld woman who developed autoimmune hyperthyroidism of Graves' disease while
on immunosuppressive therapy for liver transplantation. Signs and symptoms
of hyperthyroidism were already present when, misled by the concomitant tox
ic hepatic syndrome, liver rejection was first suspect-ed. Despite a therap
eutic level of cyclosporine, elevated serum alanine and aspartate aminotran
sferase levels were noted. Consequently, a liver biopsy was performed to ex
clude an acute rejection. The findings were consistent with acute hepatitis
without evidence of rejection. Then, the diagnosis of Graves' hyperthyroid
ism was considered and finally confirmed by finding a suppressed thyroid-st
imulating hormone, elevated thyroid hormone levels, and a high and homogene
ous thyroid uptake from radioactive iodine scan. Thyroid peroxidase antibod
y and thyroid-stimulating immunoglobulin were markedly elevated. The patien
t was treated with radioactive iodine, which resulted in improvement of sym
ptoms and resolution of abnormal liver function tests. Although the mechani
sms involved in transplant rejection and human autoimmunity are thought to
be similar, the development of Graves' disease in this patient despite ther
apeutic immunosuppression suggests that the immunological processes may be
different.