Análisis crítico de un artículo: La terapia de reemplazo con la combinación de T3 con T4 no sería mejor que T4 sola en pacientes hipotiroideos / Critical appraisal: Combined T3 and T4 replacement therapy is not better than replacement with T4 alone

Conflicting results have recently been published about the benefits of combined thyroxine (T4) and triiodothyronine (T3) in treating hypothyroid patients. However these studies may have been underpowered to detect differences in psychological well-being specifically related to thyroxine replacement. We conducted a large, double-blind, randomized controlled trial of partial substitution of 50 microg of T4 by 10 microg of T3 (T3) vs placebo (T4 alone - 50 microg of T4 replaced) in 697 hypothyroid patients. Thyroid function showed a rise in the TSH (132%), a fall in Free T4 (35%, P <0.001) and unchanged basal Free T3 levels (P=0.92). At 3 months there was a large (39%) ®placebo effect¼ improvement in ®psychiatric caseness¼ defined by the General Health Questionnaire 12 score (GHQ 12) in the control group compared with baseline and this was sustained at 12 months. Differences vs the intervention (T3) group were more modest with improvements in GHQ caseness (OR - 0.61; 95% CI: 0.42, 0.90; P=0.01) and HADS anxiety scores at 3 months (P <0.03) but not GHQ Likert scores, HADS depression, thyroid symptoms or visual analog scales of mood and the initial differences were lost at 12 months. These results may be consistent with a subgroup of patients showing transient improvement following partial substitution with T3 but do not provide conclusive evidence of specific benefit from partial substitution of T4 by T3 in patients on thyroxine replacement. They also emphasize the large and sustained ®placebo effect¼ that can follow changes in thyroid hormone administration.

Función tiroidea en una población con aporte extra de yodo / Thyroid function in a population with an extra iodine intake

Background: After 20 years of iodine salt fortification, the prevalence of goiter has decreased significantly in the rural area of Pirque, central Chile. In this location, equipment has been installed that efficiently and economically adds 0.5 mg of elemental iodine per liter of water to render it potable. Aim: To study thyroid function and urinary iodine excretion in scbool age cbildren of this zone, after two years of extra iodine intake. Material and methods: One hundred thirty four children aged 6 to 12 years old were examined. In 56 randomly chosen children a morning urine sample was obtained to measure iodine excretion. In 45 children without goiter, a blood sample was obtained to measure TSH and thyroxin. Results: In nine cbildren (7 percent) a diffuse goiter was found. Median urinary iodine excretion was 158 ug/dl. Thyroxin and TSH levels were within normal limits (8.4Ý1.1 ug/dl and 2.2Ý1.5 uU/ml respectively). During the period of iodine water supplementation there were 47 births in the zone. All newborns had normal TSH values and none had goiter. Conclusions: When present results are compared with the period before water iodination (when the prevalence of goiter was 9.6 percent and mean urinary iodine excretion was 57.6 ug/dl), it can be concluded that extra iodine intake in this rural population has not caused additional thyroid problems

Prevalencia de bocio en escolares de la zona de Pirque: efecto de la yodación de la sal / Prevalence of goiter in school children at Pirque: effects of salt iodination

Twenty years ago, Pirque was a zone with a goiter prevalence of 39 percent, to assess the effects of salt iodination on the prevalence of goiter, school age children from 4 public schools of Pirque, were examined, following WHO criteria for the diagnosis of goiter. Urinary iodine excretion was also measured. Five hundred ninety one males and 298 females aged 12.1ñ2.5 years were examined. Fifty seven children (9.6 percent) had goiter. In 53, the goiter was grade I and in 4, grade II. No sex differences were observed. Minimal and median urinary iodine excretion values were 12.6 and 57.6 ug/dll respectively. In conclusion, goiter prevalence dropped from 39 to 10 percent. The fact that iodine intake is over minimal recommendations, underscores the effectiveness of salt iodination

Infiltración adiposa difusa de la glándula tiroides asociada a amiloidosis en un paciente con insuficiencia renal crónica / Diffuse fatty infiltration of the thyroid gland associated to amyloidosis in a patient with chronic renal failure

We report a 26 years old male with secondary amyloidosis and chronic renal failure who consulted due to rapidly growing goiter associated with coarseness and dysphagia. Serum levels of thyroid hormones and TSH were normal and a neck CT scan showed a big mass in the anterior lateral regions, thet compressed neighboring structures. The patient was subjected to a total thyroidectomy and the pathological study revealed a diffuse fatty and amyloid infiltration of the thyroid gland. There was no evidence of malignancy

Evaluación clínica del vello corporal en mujeres sanas / Clinical assessment of body hair in healthy women

To study tha amount and distribution of terminal body hair in non-hirsute women consulting in a public outpatient clinic. Two hundred thirty six premenopausical women consulting in a birth control clinic or consulting for acute non-endocrinological diseases were studied. Body hair was assessed with a semi-quantitative clinical method described by Ferriman and Gallwey. Ninetyfive percent of women had a score equal or less than 5. No correlations were found between the score and body mass index or age. Partial scores over 1 were found specially in the lower abdomen, chest, superior lip and thighs. This sample of women, coming from middle and low socioeconomic levels, appears more hairlee than European or North American Women. Thus, hirsutism must be suspected with scores over 5. These results cannot be extrapolated to all Chilean women, due to differences in ethnical backgrounds

Intoxicación aguda por tiroxina en niños / Acute poisoning with thyroxine in children

Dos niñas de 5 y 14 años de edad ingresaron al hospital 4 y 8 h después de haber ingerido dosis estimadas de L-tiroxina de 72 ug*kg. En ambas pacientes la concentración sérica de T4 estaba elevada al ingresar (19 y 20 ug/dl) y las dos eran asintomáticas. Ellas fueron tratadas con Ipodato de sodio, 3 g por vía oral cada 72 h, con el propósito de bloquear la conversión de T4 a T3. Las concentraciones séricas de T4 aún permanecían elevadas 10 días después (8 y 16 ug/dl), pero las de T3 descendieron a 60 ug/dl y se mantuvieron bajo este nivel, dentro de las primeras 48 h de iniciado el tratamiento. Los pacientes, en estos casos, pueden no presentar síntomas de intoxicación, sino hasta después de 24 h de producida la ingestión; por este motivo deben ser admitidos y tratados sistemáticamente en el hospital. El Ipodato es el tratamiento de elección

Hiponatremia severa en porfiria aguda: mielinolisis pontina central como complicación de su tratamiento / Acute porphyria: central pontine myelinolysis developing during correction of severe hyponatremia

Two patients developed severe hyponatremia attributed to inappropriate antidiuretic hormone secretion during a crisis of acute porphyria, and were treated with intravenous hypertonic sodium solution. One of them developed clinical and radiological findings of pontine and extrapontine myelinolysis, which may constitute a risk in the treatment of this complication