Urinary iodine concentrations should be monitored to diagnose some thyroid gland diseases in heart transplant recipients.
BACKGROUND
According to the World Health Organization, iodine excreted in urine is a measure of its supply. According to the International Council for Control of Iodine Deficiency Disorders (ICCIDD), the urinary iodine (UI) should be >100 microg I per 1 liter of urine. Severe deficiency (SID) is diagnosed when UI is <50 microg/L and a moderate deficiency (MID) when UI is <100 microg/L.


METHODS
UI analysis among 32 heart transplant recipients (26 men and 6 women); of overall mean age of 50.4 +/- 12.6 years was performed using the modified Program Against Micronutrient Malnutrition method, a spectrophotometric measurement based on the Sandell-Kolthoff reaction. Results were compared with those of thyroid stimulating hormone (TSH; microIU/mL), of free tri-iodothyronine (FT3; pg/mL), and thyroxine (FT4; ng/dL).


RESULTS
The average UI among the whole group was 126.4 +/- 109.6 microg/L. SID occurred in 12 patients (37.5%) and MID in 4 (12.5%); namely, mean UI of 17.0 +/- 9.6 and 79.5 +/- 5.6, respectively. In the other 16 patients (50%), the average UI was high, namely, 220.1 +/- 72.1 IU/mL. TSH, FT3, and FT4 in the whole group were within normal ranges. However, FT4 values significantly differed when SID and MID patients were compared with those displaying the recommended UI: 0.8 +/- 0.2 and 0.9 +/- 0.1 versus 1.1 +/- 0.2 respectively (P < .05). We noted decreased values of TSH in 5 patients (15.6%) and of FT3 or FT4 in 6 subjects (18.8%).


CONCLUSIONS
There exists significant iodine deficiency among heart transplant recipients. Measurements of urinary iodine together with thyroid gland hormones may be essential to prevent thyroid gland disturbances in these patients.
Wozniak-Grygiel
E
E
Laboratory of Immunology and Transplantology, Silesian Centre for Heart Diseases, Zabrze, Poland.
Zeglen
S
S
Stanjek-Cichoracka
A
A
Zakliczyński
M
M
Kucewicz Czech
E
E
Zembala
M
M
D000328:Adult; D015415:Biomarkers / Q000652:urine; D005260:Female; D016027:Heart Transplantation / Q000009:adverse effects*; D006801:Humans; D006980:Hyperthyroidism / Q000097:blood / Q000453:epidemiology / Q000652:urine; D007037:Hypothyroidism / Q000097:blood / Q000453:epidemiology / Q000652:urine; D007455:Iodine / Q000652:urine*; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D013053:Spectrophotometry; D013959:Thyroid Diseases / Q000453:epidemiology* / Q000652:urine; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D015415:Biomarkers; D014284:Triiodothyronine; D013972:Thyrotropin; D007455:Iodine; D013974:Thyroxine