Giuseppe Robuschi

COMPARISON OF METHIMAZOLE, METHIMAZOLE AND SODIUM IPODATE, AND METHIMAZOLE AND SATURATED SOLUTION OF POTASSIUM IODIDE IN THE EARLY TREATMENT OF HYPERTHYROID GRAVES’DISEASE

We have evaluated three regimens for the rapid control (10 days’therapy) of thyrotoxicosis in hyperthyroid Graves’disease: methimazole (MMI, 40 mg/ day), MMI and sodium ipodate (MMI + Na Ipodate, 1 g/day and MMI and saturated solution of potassium iodide (MMI + SSKI, 6 drops twice daily). When serum T4 and T3 concentrations were analysed as the percent change from pre‐treatment values, the following results were observed. Serum T4 concentration decreased in the three treatment groups and the decrease was similar in the MMI and MMI + SSKI groups but significantly lower than in the MMI + Na ipodate group. The serum T3 concentration decreased to the normal range in all seven MMI + Na Ipodate treated patients by the fourth day of treatment and the per cent decrease in serum T3 from pre‐treatment values was significantly greater than in the MMI and MMI + SSKI treated patients. The decrease in serum T3 was similar in the latter two groups. Heart rate decreased in all three groups, but the decrease was significantly more in the MMI+Na ipodate treated patients. The present findings suggest that the rapid control of hyperthyroid Graves’disease is similar in patients treated with MMI and MMI + SSKI and that the combination of MMI + Na Ipodate is more efficacious since the decrease in serum T3 concentrations and heart rate was significantly greater in the MMI + Na ipodate‐treated patients.

Effect of sodium ipodate and iodide on free T4 and free T3 concentrations in patients with Graves’ disease

Graves’ hyperthyroid patients were treated daily for 10 days with 1 g sodium ipodate, a cholecystographic agent which exerts a blocking effect on the peripheral conversion of T4 to T3, or with 12 drops of saturated solution of potassium iodide (SSKI). Serum concentrations of free T4 (FT4) and free T3 (FT3) were measured before, during and 5 and 10 days after the administration of each drug. Sodium ipodate treatment induced a rapid decrement of serum FT4 concentrations which declined from 48.9 ± 6.6 pg/ml to 26.0 ± 2.7 pg/ml. In these patients serum FT3 concentrations declined from 12.4 ± 2.0 pg/ml to 2.5 ± 0.4 pg/ml. Ten days after sodium ipodate withdrawal, serum FT4 and FT3 concentrations returned to baseline values. In patients treated with SSKI serum FT4 concentrations declined from 51.1 ± 8.8 pg/ml to 11.3 ± 1.4 pg/ml and FT3 from 15.7 ± 2 pg/ml to 2.6 ± 0.3 pg/ml. Moreover, after therapy interruption serum free thyroid hormone concentrations returned to baseline values in these patients. Serum FT4 pattern during the study was not different between the two groups of subjects whereas serum FT3 concentrations were significantly lower in patients treated with sodium ipodate. These findings indicate that SSKI and sodium ipodate are effective in inducing a rapid decrement of serum free thyroid hormone concentrations. Therefore the employment of these drugs may be useful in the treatment of patients with thyroid storm and those undergoing thyroidectomy.

Cord blood iodothyronine and thyrotropin concentrations in newborns of mothers exposed to povidone iodine in the last trimester

In the present study, we have evaluated thyroid function in neonates at delivery and in their mothers who used vaginal povidone-iodine (PVP-I) during the last trimester of pregnancy. Newborns and their mothers without a history of iodine exposure, admitted to the same department and residing in the same geographical area served as controls. Maternal serum thyroxine (T4), triiodothyronine (T3), reverse triiodothyronine (rT3) and thyrotropin (TSH) concentrations at delivery were not significantly different between the two groups of pregnant women. Cord blood thyroid hormone concentrations in the newborns of iodine exposed mothers were not significantly different from those in control newborns. In contrast, cord blood TSH concentrations in the neonates of mothers exposed to PVP-I during the last trimester of pregnancy were significantly higher than values in control neonates (p < 0.05). These data confirm that the fetal thyroid gland, even in the last trimester of pregnancy, does not adapt completely to the inhibitory action of iodine on thyroid hormone synthesis and/or release.

Methimazole and Serum Thyroid Hormone Concentrations in Hyperthyroid Patients: Effects of Single and Multiple Daily Doses

Excerpt Thionamide drugs are traditionally administered in divided doses, a treatment schedule recommended in many textbooks of endocrinology and thyroidology. The reason for administering antithyr...

Dermorphin, a new opioid peptide, stimulates thyrotropin secretion in normal subjects

The effect of a recently described, potent opioid peptide, dermorphin (DER), on TSH secretion in euthyroid subjects has been studied. DER infused at a rate of 5.5 μg/Kg/min for30 min induced a significant increase in serum TSH concentration at 60,90, and 120 min after the infusion was begun. Treatment with naloxone administered 30 min before the DER infusion with a bolus dose of 4 mg, followed by a constant infusion of 1 μ/Kg/min for 150 min, prevented the rise in serum TSH. Naloxone administered alone did not induce any change in TSH concentration. The present findings suggest that DER has a stimulatory effect on TSH secretion, probably mediated by opioid receptors. These results, however, do not solve the question as to whether opioids have a physiological role in the control of pituitary TSH secretion.

Serum concentrations of myoglobin, creatine kinase, lactate dehydrogenase and cardiac isoenzymes in euthyroid, hypothyroid and hyperthyroid subjects.

SummarySerum concentrations of myoglobin, creatine kinase and lactate dehydrogenase were measured in 33 euthyroid, 21 hyperthyroid and 15 hypothyroid subjects. The results showed that myoglobin, creatine kinase and lactate dehydrogenase were increased and decreased in the hypoand hyperthyroid states, respectively. In addition, the concentrations of myoglobin, creatine kinase and lactate dehydrogenase values were inversely related to both the thyroxine and triiodothyronine concentrations. To study the origin of the increased muscle protein values observed in hypothyroidism, the cardiac isoenzyme fractions were measured; the results obtained support the view that the muscle enzymes are mainly derived from skeletal muscles.

The value of serum thyroglobulin measurement as a marker of cancer recurrence in the follow-up of patients previously treated for differentiated thyroid tumor

In order to verify the value of serum thyroglobulin (hTg) determination to detect cancer recurrence, 104 patients previously treated with surgical and 131I total thyroid ablation for differentiated thyroid cancer were studied. Comparison of serum hTg results and 131I total body scans (131I TBS) was attempted. In 87 patients with negative 131I TBS, serum hTg was undetectable in 80% of the patients whereas in 20% detectable amounts of hTg were measured. In 57 patients with positive 131I TBS, serum hTg was measurable in 72% of the patients whereas in 20% was undetectable. These contrasting results of serum hTg measurement and 131I TBS suggest to us the usefulness to use both tests in the detection of thyroid cancer recurrence.

Effect of metoclopramide on maternal and fetal hyperprolactinemia

To investigate the effect of metoclopramide (MET), a dopaminergic antagonist drug, on serum PRL concentration in maternal and cord blood (CB) serum, the drug was injected in 94 at term pregnant women whereas 28 mothers received saline. Maternal serum (MS) samples were obtained before MET injection and at the parturition time. According to the interval of time between MET administration and birth, MS specimens were grouped in 7 groups. CB was obtained from neonates whose mothers were injected with saline, group 0 and from newborns whose mothers were treated with MET, groups 1 to 7. In the 7 groups of women the mean PRL concentration before MET ranged between 307 and 439 ng/ml. After MET injection a significant increase has been observed in all groups with a minimum and maximal mean value of 639 and 931 ng/ml. The highest net increment of PRL has been measured ingroup 1 sampled at 5 to 30 minutes after MET. CB PRL concentration in group 0, saline treated, was not different from the values measured in group 1 to 7, treated groups, with a range between 504 and 703 ng/ml. These findings suggest that maternal lactotropes are still responsive to MET. On the opposite, fetal pituitary does not release PRL after MET injection probably because PRL secretory activity is maximal or because the dopaminergic receptors’ system is still immature.

3, 3′, 5′-Triiodothyronine concentrations in amniotic fluid at different stages of pregnancy

Since it is feasible to detect reverse T3 (rT3) in amniotic fluid, we investigated the possibility as to whether measurements of amniotic rT3 could be useful in diagnosing fetal hypothyroidism during pregnancy. In 55 amniotic fluid samples, obtained at different stages of pregnancy, we have documented increasing concentrations of this hormone. The results obtained are conflicting with previous reports. The reason for this discrepancy is not clear, however methodological differences in rT3 determination should be taken in account. The large scatter of rT3 values in amniotic fluid suggests that the diagnosis of neonatal hypothyroidism based on measurement of rT3 may require caution.

Amniotic fluid thyrotropin (TSH) following maternal administration of thyrotropin releasing hormone.

Cord blood and amniotic fluid thyrotropin (TSH), T4, T3, and rT3 concentrations were measured in 49 women who received 400 micrograms thyrotropin releasing hormone (TRH) iv during labor and in 16 control women who received saline. Cord blood serum TSH concentrations were elevated for as long as 4 hours after TRH administration and peak values (38.0 +/- 4.2 microU/ml) were observed from 61-120 minutes after TSH as compared to control values of 5.0 +/- 0.3 microU/ml. The elevations in fetal TSH concentration stimulated the fetal thyroid, resulting in a progressive increase in cord blood T4 and T3 but not rT3 concentrations. These TRH induced elevations in fetal cord blood TSH concentrations were not accompanied by increases in unconcentrated and 4 fold concentrated amniotic fluid TSH concentrations which were almost always below 0.6 microU/ml, the limit of assay sensitivity. Unconcentrated amniotic fluid T4 concentrations were barely detectable and no variation was observed between the TRH treated and saline treated mothers; amniotic fluid T3 was not detectable in any of the groups; and amniotic fluid rT3 concentrations ranged between 46.4 and 55.6 ng/dl and did not differ between groups. These findings suggest that term amniotic fluid TSH values do not reflect transient but marked elevations in fetal serum TSH concentrations and that amniotic fluid TSH determination is probably not useful in the detection of primary fetal hypothyroidism. It is possible, but unlikely, that long-term and even greater elevations in fetal serum TSH concentrations would result in increased amniotic fluid TSH concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)