The effects of different doses of oral iodized oil on goiter size, urinary iodine, and thyroid-related hormones.

The prevention of iodine deficiency is still a worldwide concern. This study, conducted in Soja in western Sudan, was carried out to evaluate the effects of a dose of iodized oil sufficient enough to give maximum protection against goiter and provide an acceptable iodine supply without side-effects over a sufficiently long period of time. Adult goitrous subjects (n = 117) were randomly assigned to three groups, A, B, and C, and received a single oral dose of 200, 400, or 800 mg iodine, respectively. Urine and blood samples were collected at the start of the study and monitored for 1 yr. In the 3 groups, mean serum T4 and median urinary iodine and serum TSH values were restored to reference limits, and these were maintained for about 1 yr. In each treatment group, about two thirds of the subjects displayed a reduction in goiter size, and the 400- and 800-mg doses were not more efficient than the 200-mg dose to accomplish normalization of thyroid hormone values. A temporary rise in TSH was noted 1 week after iodine administration in 1, 3, and 10 subjects, respectively, and 1, 0, and 3 subjects showed biochemical signs of thyrotoxicosis during the year after treatment with the 3 different doses. The data indicate that oral administration of 200 mg iodine is effective and acceptable for treating iodine deficiency in adults for 1 yr. Because of the risks of side-effects and the shortage of medical resources, higher doses are not recommended.

Prevention and treatment of endemic iodine-deficiency goiter by iodination of a municipal water supply.

A recently described method for the prevention and treatment of endemic iodine deficiency and goiter, introduction of iodine into a public water supply, was tested in Troina, a town of about 13,000 inhabitants in northeast Sicily. There, before initiation of the program, a goiter endemic of moderate severity was present, as evidenced by goiter prevalence of 55% in school children. Iodine deficiency in nongoitrous adults was indicated by daily urinary iodine excretion of 40.7 +/- 2.6 micrograms (mean +/- SE) and 24-h thyroid radioiodine uptake of 50.8 +/- 2.4%. Iodination of the water supply was initiated in November 1979 using a stream-splitting device that diverts a controlled fraction of the total water flow to a canister containing iodine crystals, where the water becomes saturated with iodine (approximately 300 mg/liter) before returning to the main stream. Except for a 15-month interruption during which governmental authorization of the program was being reconfirmed, treatment of the water has continued to the present time, initially at a level of 81 +/- 25 micrograms/liter (mean +/- SD) and since resumption at a level of 46.5 +/- 5 micrograms/liter. Iodination of the water was followed by a prompt and marked reduction in goiter prevalence, and by improvement in biochemical indices of iodine deficiency. By April 1983, overall goiter frequency in school children had declined to 6.1%, and large goiters (WHO Grade 2) had virtually disappeared. By January 1984, daily urinary iodine excretion had increased to 85.6 +/- 6.5 (SEM) micrograms and radioiodine uptake had decreased to 40.7 +/- 4.7%. Serum thyroid-related hormone concentrations were as follows (pretreatment vs. November-December 1983): T4, 5.8 +/- 0.3 vs. 8.4 +/- 0.3 microgram/dl; T3, 1.6 +/- 0.05 vs. 1.2 +/- 0.06 ng/ml; TSH, 3.7 +/- 0.2 vs. 2.2 +/- 0.1 microU/ml; all changes being statistically significant. By late 1983, serum T4, T3, and TSH values in Troina were almost identical to those in Catania, a community in which iodine deficiency is not present (goiter prevalence in school children, 2.2%). In contrast, in Troina serum T4 concentrations were significantly higher and serum TSH concentrations were significantly lower than those in Maniaci, a iodine-deficient town near Troina, in which the water was not iodinated. Iodinated water was well tolerated by the population of Troina, and no adverse effects of water iodination, including any increase in the frequency of hyperthyroidism, was observed. At present prices, the cost of the water iodination program in Troina would be approximately 4 cents (U.S.) per person per year.(ABSTRACT TRUNCATED AT 400 WORDS)

Fetal hypothyroidism and maternal thyroid status in severe endemic goiter.

The relationship between maternal thyroid function and newborn thyroid function was studied in a region of very severe endemic goiter (Ubangi, Republic of Zaïre). T4, T3, and TSH concentrations were measured in the sera of 56 mothers (at the time of delivery) and 60 newborns (in the cord). The results obtained in these groups (untreated) were compared with those obtained in two control groups, comprising 53 mothers whose iodine deficiency had been corrected by the injection of iodized oil and 68 neonates born to such mothers. The results show that the mean (+/- SEM) T4 serum concentration (micrograms per dl) was 11.5 +/- 0.7 in the untreated mothers compared with 15.7 +/- 0.7 in the treated mothers (P less than 0.001), and 9.4 +/- 0.8 in the untreated newborns compared with 12.4 +/- 0.5 in the newborns of treated mothers (P less than 0.01). The values observed for the mean T3 serum concentrations (nanograms per dl) in the same groups were 171 +/- 10 and 154 +/- 9 (mothers; P greater than 0.05) and 68 +/- 6 and 55 +/- 6 (newborns; P greater than 0.05); the mean TSH serum concentrations (microunits per ml) were 8.7 (7.6 - 9.9) and 5.4 (4.9 - 5.9; mothers; P less than 0.001) and 19.6 (16.6 - 23.2) and 6.4 (5.8 - 7.0; newborns; P less than 0.001). The proportion of untreated newborns, i.e. 40%, with individual TSH values deviating by more than 2 SDS above the mean of the treated newborns is much greater than the corresponding proportion, i.e. 15%, of untreated mothers in relation to the treated ones. In 6 out of 34 untreated newborns, definite biochemical signs of congenital hypothyroidism were observed. Correlation coefficients were calculated between the untreated subjects. A positive correlation coefficient of 0.80 (P less than 0.001) was observed between the serum T4 concentrations of the mothers and those of the newborns, and one of 0.61 (P less than 0.001) was observed between their respective serum TSH values. Significant inverse correlations were observed between maternal serum T4 and cord serum TSH (-0.79; P less than 0.001) and between cord T4 concentrations and maternal TSH concentrations (-0.57; P less than 0.01). No definite trend is observed between the variations of serum T3 on one hand, and those of serum T4 or serum TSH on the other hand. Out of 51 mothers in whom serum T4 was determined, 11 showed values below 8 micrograms /dl; the newborns of those mothers showed very low serum T4 values (5.5 +/- 1.6 micrograms/100 ml) and extremely high serum TSH levels [144 (98-210) microU/ml]. It is concluded that, contrary to the situation observed in physiological conditions, maternal thyroid function in regions of severe endemic goiter is a good indicator of newborn thyroid function. The reasons for this probably lie in the influence of environmental factors acting simultaneously on the mother and the fetus.

Strategy of goitre and cretinism control in Central Africa.

Goitre prevalence in Ubangi Mongala (north-western Zaïre) ranges from 27 to 60 per cent in the male population and from 48 to 78 per cent in the female population; the prevalence of cretinism ranges between 0.7 and 7.6 per cent. This severe endemia affects 1.5 million inhabitants and constitutes a major public health problem. If administered to an entire population, single injections of slowly resorbable iodized oil can reduce goitre prevalence substantially, correct the iodine deficiency and restore normal thyroid function for a period of 3 to 7 years, depending on the parameter considered. The cost of programme of endemic goitre prevention based on this method can be estimated at 0.07 US dollars per person and per year of protection. A strategy of goitre and cretinism control in Central Africa, using iodized oil in an attack phase and iodized salt in a follow-up phase, is proposed. The organization of this programme will be dovetailed into other public health activities and will strengthen the basic health service framework.

PIP: Goiter prevalence in Ubangi Mongala (northwest Zaire) ranges from 27-60% in the male population and from 48-78% in the female population; the prevalence of cretinism ranges from 0.7-7.6%. The severe endemia affects 1.5 million inhabitants and constitutes a major public health problem. If administered to an entire population, single injections of slowly resorbable iodized oil can reduce goiter prevalence substantially, correct the iodine deficiency, and restore normal thyroid function for a period of 3-7 years, depending on the parameter considered. The cost of such a program of endemic goiter prevention based on this method can be estimated at 0.07 US dollars/person/year of protection. A strategy of goiter and cretinism control in Central Africa, using iodized oil in an attack phase and iodized salt in a follow-up phase is proposed. The organization of this program will be dovetailed into other public health activities and will strengthen the basic health service framework.

Superiority of thyrotropin to thyroxine as a tool in the screening for congenital hypothyroidism by the filter paper spot technique.

The effects of storage on the assessment of thyroxine (T4) and thyrotropin (TSH) were evaluated in blood spots collected on filter paper according to the methods commonly used in screening for congenital hypothyroidism. Comparisons were made with serum values obtained simultaneously in the same subjects. In samples stored at room temperature a clear-cut decrease in T4 was observed after 24 hours while TSH was stable for at least 15 days. Spot samples collected in an area of severe endemic goiter in Africa and analyzed in Brussels displayed a systematic decrease in T4 (up to 133 nmol/l) while TSH was fairly stable. Spot samples collected in Belgium were stored at -18 degrees C and were reassayed after 1 year; they did not show any significant change in TSH but a systematic decrease in T4. We conclude that spot TSH is the tool of choice in screening for congenital hypothyroidism particularly in developing countries and that spot T4 should not be used for field studies or under any circumstances in which assays cannot be performed very soon after blood collection.

Autonomy in endemic goiter.

The occurrence of hyperthyroidism in many individuals after introduction of iodine prophylaxis in endemic goiter areas can have dramatic consequences for the affected individuals. It indicates that in such individuals the increase of serum thyroid hormone level in response to iodine supplementation does not exert its normal negative feedback on thyroid activity, ie, that in such individuals some thyroid tissue has become autonomous. In this short review we summarize what is known about the possible mechanisms, cause, diagnosis, and consequences of thyroid autonomy.

Bacterial meningitis complicated by spinal arachnoiditis: diagnostic contribution of Tc-99m-inulin myeloscintigraphy.

Six cases of bacterial meningitis with myeloscintigraphic evidence of medullary arachnoiditis are reported. Four patients has tuberculous meningitis, another showed severe myelopathy, and the last was suspected to have hydrocephalus. Arachnoiditis is suspected when the earliest images show a sharp decrease of tracer concentration. Scintigraphy began 2 hours after lumbar injection of Tc-99m-Polyfructosan and imaging was performed at intervals of 2, 4, and 6 hours. This method has proved easy, innoculous, reproducible, and, owing to the small amount of irradiation, studies may be repeated during and after therapy. Scintigraphy is superior to the Queckenstedt test becaise it detects partial blocks and localizes lesions.

[Therapeutic indications in hyperthyroidism (author's transl)]. / Les indications thérapeutiques dans l'hyperthyroïdie.

The administration of synthetic antithyroid drugs or of l131, and subtotal resection of the thyroid gland remain the treatments of hyperthyroidism. Precise criteria will determine the choice. Surgery is the treatment of large goitres, of associated ophthalmic disorders and of recurrence after medical treatment. Drugs are indicated at the first occurrence of hyperthyroidism in young subjects with a small goitre; it will also be used as a preparation for surgery associated to Lugol and Levothyroxine. Finally l131 is indicated in medium size hyperthyroid goitres in patients over 45 years. Each treatment has advantages and drawbacks which must be taken into account for the therapeutic choice and the follow-up.

[Goitrogens of vegetable origin as possible aetiological factors in endemic goiter (author's transl)]. / Intervention de goitrigènes d'origine végétale dans l'étiologie du goitre endémique.

Ingestion of unsoaked cassava is followed by an increase of the thiocyanate production in men and in rats. Even a moderate increase of serum SCN concentration induces, in chronic conditions, a clearcut goitrogenic effect characterized by the aggravation of the effects of a preexisting iodine deficiency. The mechanism of the antithyroid action of SCN at low concentrations, lies in an acceleration of the exit rate of thyroidal iodide; this effect cannot be identified by the usual clinical investigation with Iodine131.

[Pathogenesis of endemic goiter: evidence of a dietary factor different from iodine deficiency (author's transl)]. / Mise en évidence d'un facteur alimentaire distinct de la carence iodée dans la pathogénie du goitre.

The role of cassava was investigated in particularly severe endemic goiter area (Ubangi). Dietary intake of cassava induces an increase of plasma thiocyanate concentration and an increase of urinary excretion of stable iodine. Generalized iodine deficiency induces very high thyroid uptakes; the other parameters of thyroid function are more or less affected according to the dietary intake of thiocyanate. When thiocyanate intake is high an adaptation is obtained only at the expense of a drop of plasma T4 level and very high increase of plasma TSH.

[Adverse effect of amniofetography on fetal thyroid function (author's transl)]. / Amniofoetographie et fonction thyroïdienne foetale.

Amniofetography is a valuable tool for the diagnosis of fetal malformations. We have studied the effect of radiopaques dyes, containing large amounts of iodide, on fetal thyroid function. We have performed serial determinations of serum thyrotropin and thyroxine in seven newborn infants submitted to amniofetography. This work demonstrates that amniofetography induces a transient impairment of fetal thyroid function.

[Use of plasmapheresis in a case of Graves' disease with malignant ophthalmopathy (author's transl)]. / Exophtalmie maligne traitée par échange plasmatique. Rapport d'un cas.

A short trial with high doses of prednisolone to treat a 62 year-old woman with malignant ophthalmopathy due to Graves disease yielded an unsatisfactory improvement after 5-6 days. The authors decided therefore to use plasmapheresis, 4 plasma exchanges of 2.5 liters each associated with prednisolone (80 ng/day) and azathioprine (100 mg/day). This therapeutic approach resulted in a spectacular improvement obtained after less than 2 weeks: normalization of thyroid function, improvement of all ophthalmological indices confirmed by radiology (C.A.T.) of the retroocular region. The rapid and important improvement obtained after such a short period of time is in favor or the major role of plasmapheresis in this combined therapy of malignant Graves' ophthalmopathy.