Thyroid function tests in patients with acquired immune deficiency syndrome and healthy HIV1-positive out-patients

The thyroid function tests as well as evidence of thyroiditis were studied in 18 male patients with acquired immune deficiency syndrome (AIDS) and 12 healthy HIV1-positive persons compared with an age-matched control group. Serum total thyroxine was not significantly different between the groups, but both serum total triiodothyronine, triiodothyronine uptake test, and free thyroid hormone indices showed significantly decreasing values from HIV1-positive healthy persons to AIDS patients compared with controls (P value from less than 0.05 to less 0.001). Serum TBG was elevated in HIV1-positive subjects and in patients with AIDS, with a significant inverse correlation with the T3-uptake test (Spearman's rho = 0.657, P less than 0.01). There was no correlation between thyroxine binding globulin and the other measured variables. The serum level of thyrotropine was not significantly different in the groups, whereas serum thyroglobulin was significantly lowered in the AIDS group. There was no correlation between thyroid function variables and survival time, hepatic function and ratio of T-helper to T-suppressor cells. No evidence of thyroiditis was observed. In conclusion thyroid tests showed an atypical outcome in HIV1-positive patients with or without AIDS compared with the pattern normally seen in non-thyroid illness, and should, therefore, caution the interpretation of the biochemical changes when diagnosing abnormal thyroid function in these patients.