October 1982

Abnormalities in Thyroid Function Tests in Patients Admitted to a Medical Service

Author Affiliations

From the Department of Medicine, University of North Carolina School of Medicine, Chapel Hill. Dr Gooch's present affiliation is the Department of Medicine, Vanderbilt University, Nashville, Tenn.

Arch Intern Med. 1982;142(10):1801-1805. doi:10.1001/archinte.1982.00340230041008

• Serum thyroid hormone, thyrotropin (TSH) and thyroxinebinding globulin (TBG) concentrations, free thyroxine index values, and free thyroxine concentrations were measured at the time of admission in all 77 patients hospitalized on a medical service on four separate days. Serum thyroxine (T4) concentrations and serum free T4 index values were decreased in 19.5% and 11.7%, respectively, and increased in 3.9% and 11.7%, respectively; serum free T4 concentrations were decreased in 6.8% and increased in 5.4%. Six patients (7.8%) had increased serum TSH concentrations. Serum triiodothyronine (T3) concentrations were decreased in 26.0% and reverse triiodothyronine (rT3) concentrations were increased in 29.9%. None had manifestations of thyroid disease. These results indicate that available thyroid function tests may give misleading results in patients with nonthyrold illness and suggest that caution be exercised in diagnosing thyroid disease in hospitalized patients.

(Arch Intern Med 1982;142:1801-1805)