The measurement of fecal thyroxine in the diagnosis of thyrotoxicosis factitia.
Two patients with prolonged thyrotoxicosis are presented with low radioiodide uptake, low-normal serum thyroglobulin concentrations, and low iodide content of the neck on x-ray fluorescence studies. The surreptitious intake of thyroid hormone was directly proven by a high fecal concentration of T4 (12.38 and 23.99 nmol/g) compared with low concentrations in healthy subjects (1.03 +/- 0.64 nmol/g; mean +/- SD, n = 6) and in patients with hyperthyroidism due to Graves' disease (1.93 +/- 1.86; n = 8). Fecal thyroid hormone measurement may help to provide formal proof of factitious thyrotoxicosis.
Bouillon
R
R
Unit of Endocrinology, Katholieke Universiteit, Leuven, Belgium.
Verresen
L
L
Staels
F
F
Bex
M
M
De Vos
P
P
De Roo
M
M
D000328:Adult; D015415:Biomarkers / Q000032:analysis; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D007455:Iodine / Q000032:analysis; D008875:Middle Aged; D015203:Reproducibility of Results; D013954:Thyroglobulin / Q000032:analysis; D013971:Thyrotoxicosis / Q000175:diagnosis* / Q000378:metabolism; D013974:Thyroxine / Q000032:analysis* / Q000378:metabolism
D015415:Biomarkers; D013954:Thyroglobulin; D007455:Iodine; D013974:Thyroxine