A method in field measurement of urinary iodine.

The objective of this study is to determine a very cheap, reliable, relatively rapid portable field unit for quantitative urinary iodine measurements. As Individual Urine Excretion (IUE) approximate those of Daily Iodine Intake (DII), iodine deficiency can be measured in casual urine samples of individual. Using the criteria, the frying pot method has been introduced and modified from the long and tedious Zak’s method after Pino et al, and Robbins and Dunn et al. This modified method has many advantages. Such the assay takes 84 tubes of urine per pot in100o C paraffin oil bath and changes into water. It has been shortened from one hour to 25 minutes. Change of color to intermediate violet is observed by adding ferroine as the indicator, resulting in a standard curve reading the concentration of iodine being, in micrograms per liter. The results of 255 subjects from Mukdaharn Province indicated the reliability of the method as the results of which are the same as those using in the heating block and spectrophotometespectrophotomete. This has been confirmed by the results of 1,007 samples. This new technique provides good results; between oil and water, the results on using water are even better. This saves much money modification reduces significantly by lowering the cost of equipment. It is rapid, simple and reliable. The method is portable and valuable for measuring and monitoring iodine deficiency studies and for epidemiological studies of iodine deficiency its control in developing countries.

Iodized salt and iodized water in the control of iodine deficiency disorders (IDD) in Thailand.

The use of drinking water as an additional vehicle for iodine to common salt has its origins in the fact that a low and irregular intake of common salt has led to a high prevalence of goitre in the north of Thailand. The distribution of salt in the north is poor. Culturally water is offered to passers-by and guests in every house. Thus, iodized salt and iodized water are combined to increase the efficacy of both, for children in primary schools in a village in Nan province where goitre is prevalent. At the end of 12 months of a strictly controlled study in 172 placebo and 114 treated subjects, the prevalence in the treated group was reduced dramatically from 60.2 to 10.5%. The urine and serum findings in the post-test samples became normal when compared with those of the pre-test samples. Both iodized salt and iodized water have been used to help relieve iodine deficiency to date. No complications were found in this series of volunteers. Monitoring and evaluation of the method showed that, if the daily dose of iodized salt was consistently 50ppm and that of iodized water 100mg per litre, this can be continued indefinitely until all areas of the country are fully developed. In conclusion, using combined iodized products under close supervision is definitely more effective than using iodized salt or iodized water alone.

Urine iodine inresligalion in Thailand.

The heating block method is a method for the routine determination of urine iodine that has been modified from the Program Against Micronutrient Malnutrition (PAMM) method. Normal values of adult urine iodine (age 35-70 years) in Bangkok were (mean + SD) 110.9+ 74.6 with a median values of 96.8 ตg/L (n = 66). Urine iodine values of adults from Maehongson and Petchabun were (mean + SD) 465.1+ 293.1 with a median value of 399.5 ตg/L (n=86), and 127.8+ 74.1 with a median value of 115.4 mg/L (n = 140), respectively. The mean and SD of the iodine content of urine from school children (age 7-12 years) in Uttraradit, Maehongson and Trang were 401.0+ 373.2 (n = 77), 1,171.1+ 1,078.4 (n = 97) and 275.0+ 399.4 (n = 46), and the median values were 264.5, 998.6 and 137.0 mg/L, respectively. There was no change in urine iodine concentration over three years despite storage a 37oC, 4 oC and 0 oC. We have participated in the PAMM-Centers for Disease Control and Prevention (CDC) Inter-Laboratory Urine Iodine Quality Assurance Program to fulfill quality assurance criteria in our testing. The results of three blind urine iodine levels were well correlated to consensus mean and %CV for inter assays were less than 15.

Tc-99m MIBI scintimammography (SMM) in the evaluation of palpable breast masses.

Radionuclide breast imaging, also called scintimammography (SMM) was performed using Tc-99m MIBI in 37 patients with palpable breast masses. A total of 38 lesions were analyzed. Twenty cases subsequently underwent modified radical mastectomy while the remainder underwent only biopsy or fine needle aspiration for histologic proof. The average size of the masses were 3.03+1.61 x 4.10+2.89 cm in diameter. Twenty-six lesions were malignant and 12 were benign; 23 malignancies showed positive MIBI uptake but three did not. The false negative cases were all invasive ductal carcinomas. Nine benign lesions were true negatives and three were false positives. They were mastitis, foreign-body granuloma and fat necrosis which chronic inflammation. Of 14 cases which histologically proved to have axillary node metastasis, only 7 revealed positive MIBI uptake. The sensitivity and spectively. However, in the detection of axillary node metastasis, the sensitivity was only 50 percent. Thus, Tc-99m MIBI SMM is helpful in the diagnosis of routine mammography. However, the imaging is not accurate enough for the detection of axillary node metastasis. In addition, Tc-99m MIBUI SMM also plays an important role in terms of prognosis and therapeutic planning in patients with breast cancer.

An investigation into methods of urine iodine analysis for use among villagers with goitre.

A modified Zak’s method has been used in this laboratory, but was subjected to contamination and produced occasional inconsistent results. Two simple ways for the determination of iodine in urine are herein described. The better one is by modified PAMM method. Briefly, destruction of organic matter in urine by acid digestion is carried out prior to determination by the Sandell and Kolthoff reaction. The Coefficient of Variation (CV) is below 10%. Iodine contents as low as 6.5 ug/L, can be detected. The proposed acid digestion procedure offers some advantages over the traditional acid digestion : e.g. low iodine losses, not complicated, and less harsh digestion. The method does not require large samples (250 ul or below) and one technician can easily handle 100 samples per day. The results obtained by this method are well correlated between the simple methods and agree with those recorded by other workers. This is also in agreement with Zak’s method (Intraclass Correlation Coefficient of 0.55). The proposed method is rapid, simple, cheap and suitable for the research investigations on iodine deficiency goitre in areas where it is endemic.

Optimized nuclear techniques and thyroid function studies in the newborn in iodine-deficient areas of Thailand.

Cord blood samples, as sera (n=4,753) and dried blood spots (n=855) obtained from subjects in iodinedeficient districts in northern Thailand, were studied for T4 and TSH. The methodology was optimized by the used of NETRIA bilk reagents and in-house methods were developed to adapt them for cost reduction, convenience and precision/accuracy. The biochemical findings with cut-off values at < 3 µg/dl for T4 and >50 mIU/L for TSH as confirmed by <1ng/dl for FT47 showed 16 cases (0.34%) of neonatal chemical hypothyroidism (NCH) varying from 0.18 to 1.59 percent of 4,753 cases. Out of the total 4,753 cases, 1.45 percent (n=96) could benefit from thyroxine administration. In this research project, the screening indicated a mild to moderate degree of IDD severity. The findings are useful for epidemiological monitoring and for advocacy of the IDD prevention and control programme.

Iodine deficiency disorders: Recent experience with iodine technology in Thailand.

For the control Iodine Deficiency Disorders (IDD) in Thailand, simple methods for iodination of various food supplements have been introduced by making use of: a) a single bottle of concentrated KIO3 solution which can be prepared by village health volunteers. Iodine may be administered by consumers by dripping the concentrate into drinking water containers belonging to village households, water for school lunch programmes, by spray mixing with salt or by dripping into fish sauce. b) twin bottle for instant detection of iodine in salt and water. This instant test is very useful for on site monitoring and hence surveillance. On a mass scale, iodination of common salt was undertaken by a simple but high capacity spraying machine or by manual mixing on a spraying table. At village level, salt iodination can be undertaken by hand spraying in a plastic basin. Iodination of drinking water can be facilitated either by using a single dropper bottle of conc KIO3 solution, or iodinators. On a limited scale, oral lipiodol has been utilized with success and the synthesis of iodized oil has been attempted. Supporting evidence from field trials confirmed the effectiveness of present methods of control via the iodated salt programme, (1962-1968), iodinated water in village households and school lunch programmes (1986-1988), iodinated water by iodinators (1981-1988), oral iodized oil (1987-1989), and iodinated water and iodated salt (1988-1989). Education transfer, and pitfalls found in the control and evaluation programmes were carefully followed up. Future projections of the control programme have been discussed.

Perchlorate discharge test.

A variety of perchlorate discharge techniques was performed and the criteria for interpretation varied according to the techniques employed. The modified technique, 10 microcurrie of Na131 I was injected into the patient with a 10 minute serial recording for 1 hour ; KC 104 300 mg/25 ml was given orally and continued with 10 minute serial recording for 30 minutes. This technique can identify the iodide transport defect and organic binding defect of the thyroid gland, and trapping function of the gland. In 25 mormal subjects, the thyroid131 I- content increased during a 60 minute serial recording and after KC 104 was given. The discharge observed during 90 minutes ranged from 1% to (- 55.7%). The range at the 20 – minute uptake is from 4.70% to 11.66% (X ฑ 2 SD). In 15 patients, 3 patients had iodide transport defect, 9 patients organic binding detect, while such defects could not be found for the remaining patients. However, it is possible that the remaining three may have other kinds of defects such as iodotyrosine coupling defect, iodotyrosine dehalogenase defect or abnormal secretion of iodoprotein.