title: Reevaluation of stringent low iodine diet in outpatient preparation for radioiodine examination and therapy.
abstract: To decrease total body iodine is a key point in preparation for radioiodine study and therapy. We introduced a stringent self-managed low iodine diet (LID) and compared the outcome to that of the conventional restricted iodine diet (RID) for outpatients. We measured urine iodine to creatinine ratios (I/Cr) in patients prepared with RID for one week, LID for one week, or LID for two weeks. Mean urinary iodine excretion after RID for one week (n = 210) was 182.2 microg/gCr (range, 13-986 microg/gCr; standard deviation (SD) = 158.5) not reaching below the recommended level (I/Cr<100 microg/gCr). Urinary iodine excretion after LID for one week (n = 15) showed a lower mean urinary iodine level (I/Cr 119.4 microg/gCr; range, 23-218 microg/gCr; SD = 55.9) than RID for one-week, and two-week LID (n = 17) showed an even lower mean level (I/Cr 63.1 microg/gCr; range, 7-134 microg/gCr; SD = 38.7). The one-week LID period adequately (recommended level of I/Cr being less than 100 microg/gCr) prepared 26% of the patients, while two-weeks on the diet adequately prepared 70% of the patients. Furthermore, none of the two-week LID patients had I/Cr>150 microg/gCr, although a significantly greater number of one-week LID patients (19%) did. Our self-managed, outpatient LID successfully induced iodine deficiency, and two-week LID may be recommended for preparation in radioiodine study and therapy for thyroid cancer.
authors.affiliation: Kuma Hospital, Shimoyamate-dori, Kobe, Japan.
authors.forename: Chisato
authors.initials: C
authors.lastname: Tomoda
authors.forename: Takashi
authors.initials: T
authors.lastname: Uruno
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Takamura
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ito
authors.forename: Akihiro
authors.initials: A
authors.lastname: Miya
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Fumio
authors.initials: F
authors.lastname: Matsuzuka
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Amino
authors.forename: Kanji
authors.initials: K
authors.lastname: Kuma
authors.forename: Akira
authors.initials: A
authors.lastname: Miyauchi
mesh_terms: D000328:Adult; D003404:Creatinine / Q000652:urine; D004032:Diet; D005260:Female; D006801:Humans; D007455:Iodine / Q000008:administration & dosage* / Q000172:deficiency / Q000652:urine; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy / Q000601:surgery; D013965:Thyroidectomy
chemical_list: D007457:Iodine Radioisotopes; D007455:Iodine; D003404:Creatinine