To the Editor.
—We read with interest the article by Azizi1 in the January Archives and the letter by JiménezAlonso et al2 and Azizi's reply.3 We can confirm Azizi's data in a greater number of patients, at least in part.We, too, have studied the serum γ-glutamyl transferase (GGT) levels in untreated Graves' disease (44 patients) and Plummer's disease (ten patients). Our patients were compared with 100 healthy, age- and sex-matched control subjects. The diagnosis of thyrotoxicosis was based on clinical findings and measurement of serum triiodothyronine (T3) and thyroxine (T4) by radioimmunoassay, T3 resin uptake (T3RU), (free T4 index [FT4I] and free T3 index [FT3I] were calculated [T3xT3 RU, T4xT3 RU, respectively]), radioiodine uptake of thyroid at two and 24 hours, and scintiscans (with or without thyrotropin given previously), for patients and controls, respectively. Serum GGT was assayed by a commercial GGT test (Boehringer/Ingelheim, FRG) based on
Konrady A, Fenyvesi G, Rendes E. Serum ?-Glutamyl Transferase Activity in Thyrotoxicosis. Arch Intern Med. 1985;145(1):179. doi:10.1001/archinte.1985.00360010227048