Miscellaneous
	Centanni et al., Rome, Italy, analyzed the amount of T4 that is required to suppress TSH in 36 patients (age 15–74 years) with histologically proven atrophic gastritis of the corpus (n=24) or antrum (n=12). Results were compared with 72 controls. The dose of T4 given was corrected for body mass index (BMI). The results were that in the controls 3.9 ± 0.9 µg T4/BMI was required to suppress TSH whereas in patients with gastritis this figure was 5.4 ± 1.2 µg T4/BMI. Patients with antral gastritis needed a lower dose than with atrophic gastritis of the corpus but still significantly higher than in controls. If in addition to atrophic gastritis of the corpus, Helicobacter pylori infection was present as well, even a higher T4 dose was necessary to suppress TSH i.e. 5.9 ± 1.1µg T4/BMI. Treatment of Helicobacter infection lowered the TSH suppressive dose. When 10 goitrous control subjects on T4 therapy were given omeprazole (proton-pump inhibitor of gastric acid secretion) serum TSH increased that was reversed by increasing the L-T4 dose. The authors conclude that impaired acid secretion might negatively affect the absorbed dose of T4. Comment: Although the results of this study are suggestive indeed of a pertinent role of gastric acid in T4 absorption, prove is not fully delivered because apart from decreased gastric acid secretion by gastritis or omeprazole, other unknown effects caused by gastritis or omeprazole may play a role as well. Full proof is obtained if gastric fluid, recovered from the controls themselves, when returned while omeprazole is being continued, reverses the increase in TSH effected by omeprazole without a change in the oral T4 dose. Azizi et al., Tehran, Islamic Republic of Iran, tested the safety of methimazole therapy (MMI) in breastfed infants, given to thyrotoxic nursing mothers. Two groups were discerned: Gr 1 of 46 mothers receiving 20 mg MMI/day for 12 months, and Gr 2 of 42 mothers receiving 30 mg MMI/day during the first month, 10 mg/day for the second month, and 5–10 mg/day for additional 10 months of therapy. Thyroid function in the offspring was tested at 1, 2, 6 and 12 months after initiation of therapy, and then at 48–86 months of life, and compared to basal values and to control children. MMI serum concentrations and IQ were also being measured. No adverse effects were seen in treated mothers and their children. The mean IQ of children of treated mothers was 103 ± 10 virtual the same as in control children being 103 ± 16. There were no differences in verbal and functional IQ and their components. The authors conclude that doses between 20 and 30 mg to lactating mothers for one year do not cause serious effects on thyroid function and intellectual development of their breast-fed infants. Gartner et al., Munich, Germany, reported the effect of selenium supplementation to critical ill patients on thyroid hormone levels and clinical outcome. Forty-two patients were studied and they found that in the selenium treated group overall mortality was 33.5% vs. 52 % in controls (p=0.13). Thyroid hormone levels increased in those patients with clinical improvement independent of plasma selenium. The authors conclude that administration of selenium improves clinical outcome but has no direct effect on free and total hormone levels, and suggest that any decreased deiodinase activity in these patients can not be caused by selenium deficiency. Comment: Although prognosis in the selenium treated group is nummerically better, this improvement is certainly not statistically significant different from the group not treated with selenium. Kwakkel et al., Amsterdam, The Netherlands, looked for genomic TSH-R mutations of exon 1,2,5,9 and part of 10, in 37 patients with non-autoimmune hypothyroidism and 18 with non-autoimmune hyperthyroidism. Autoimmunity was excluded by a TPO level < 300 kU/L and absence of TBII. This group of patients represented 7% of a total group of patients with abnormal thyroid function. In only 1/55 patients a TSH-R mutation was detected. Pingitore et al., Pisa, Italy, assessed the role of serum T3 as a predictor of prognosis in 167 consecutive patients with post-ischemic or idiopathic dilated cardiomyopathy. Two patient groups were discerned: Group I of 57 patients with subnormal FT3 and group II of 110 patients with a normal FT3. At univariate analysis FT3 was the most important predictor of cumulative death (p<0.03) followed by age (p<0.02). Comment: A similar finding in patients with acute myocardial infarction was already published almost 25 years ago! See: Smith et al., Eur J Clin Invest 1978;8:99-102. Svensson et al., Malmö, Sweden, reported the results of thyroid volume measurement by ultrasound in 598 children and adolescents, and found that girls had a significantly larger thyroid volume than boys when thyroid volume was expressed as a function of height, weight, and body surface area, but not when expressed as a function of age. The best predictor of thyroid volume in boys and girls was body surface area followed by age, weight and height. This study was done in an iodine sufficient area and the authors conclude that interpretation of thyroid volume should include both age as well as anthropometric measurements. They propose the use of a multivariate model using age and body surface area as predictors of thyroid volume. Comment: It should be realized that using such a model is most probably of no value in areas of iodine deficiency. Schmiegelow et al., Copenhagen, Denmark, reported the effects of craniospinal irradiation (CSI) in 29 children and cranial irradiation (CIR) in 42 children, all with a brain tumor. Both treatments resulted in a similar biological effective dose to the hypothalamic pituitary region. Hypothyroidism with elevated TSH was present in 12/29 CSI and 5/42 CIR treatments. In only 2 patients central hypothyroidism was detected. CSI patients had significantly higher median serum TSH levels as compared to CIR patients and controls. No differences in TSH were present between the latter two groups. Any additional chemotherapy had no influence on thyroid function in either group. The higher median TSH level and percentage of primary hypothyroidism in the CSI patients is explained by inclusion of the spinal field in the irradiated area, resulting in damage to the thyroid. Caraccio et al., Pisa, Italy, measured endothelium-dependent vasodilatation in 14 patients with subclinical hypothyroidism and compared the results with 28 healthy controls. In the patients mean serum cholesterol was 5.6 mmol/L. The control group was split into: group A, mean cholesterol 4.4 mmol/L, and group B, mean cholesterol 5.6 mmol/L. Forearm blood flow (FBF) response to intrabrachial acetylcholine (an endothelium-dependent vasodilatator) under basal conditions and during infusion with an inhibitor of nitric oxide synthase were evaluated. The authors found that before T4 treatment endotheliumdependent vasodilatation in subclinical hypothyroid patients was impaired due to reduced nitric oxide availability and only in part by mild dyslipidemia. Six months of T4 replacement therapy restored the found impairment towards normality. Comment: It seems now more and more evident that on a biochemical and physiological basis abnormalities are present even in subclinical hypothyroidism. However, the big question is if these abnormalities have a negative impact on the individual in the long run when subclinical hypothyroidism is not being treated.