24 h-kinetics of iodide uptake in amiodarone induced hypothyroidism.
Amiodarone induced hypothyroidism (AIH) is assumed to result from a failure of the thyroid to escape from the inhibitory effect of inorganic iodine on its organification as a consequence of uninhibited iodide trapping. This hypothesis was supported by the 24h kinetics of radioiodine uptake in a patient with AIH. 131I uptake reached a maximum after 2h and remained unchanged from 2h to 24h. 131I uptake was in the normal range from 1 1/2h to 7h and clearly subnormal after 9h. The normal early 131I uptake was due to the non inhibition of the iodide-concentrating mechanism and the low 24h radioactivity to the decreased iodide organification. These findings presumably explain the mechanism of AIH.
Unger
J
J
Department of Endocrinology, Erasme Hospital, Brussels, Belgium.
Surmont
D W
DW
Sarot
J
J
Soupart
A
A
Dumont
J E
JE
D000368:Aged; D000369:Aged, 80 and over; D000638:Amiodarone / Q000009:adverse effects*; D001693:Biological Transport, Active; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000139:chemically induced / Q000378:metabolism*; D007454:Iodides / Q000493:pharmacokinetics*; D007457:Iodine Radioisotopes / Q000493:pharmacokinetics; D007700:Kinetics; D013961:Thyroid Gland / Q000378:metabolism
D007454:Iodides; D007457:Iodine Radioisotopes; D000638:Amiodarone