Hipotiroidismo refractario idiopático: un caso clínico / Idiopathic refractory hypothyroidism: case report

Introducción: El hipotiroidismo constituye una patología frecuente, y su tratamiento habitual es el suplemento de levotiroxina (LT4) oral (VO). Sin embargo, existen casos inhabituales donde no es posible corregir esta condición a pesar de la utilización de LT4 en dosis alta. El hipotiroidismo refractario se define como la persistencia del hipotiroidismo a pesar del uso de LT4 > 1,9 ug/kg/día. La prevalencia del hipotiroidismo refractario no ha sido suficientemente documentada hasta ahora. Descripción del caso: Mujer de 53 años con antecedentes de hipotiroidismo, obesidad, dislipidemia, hipertensión arterial e insulinorresistencia. Fue derivada desde APS a nivel terciario por hipotiroidismo persistente a pesar del uso de LT4 800 ug/día y liotironina 80 ug/día. En forma ambulatoria se descartaron distintas causas, como mala adhesión al tratamiento, pseudo-malabsorción, síndromes de malabsorción; interacciones farmacológicas o interacciones alimentarias. Ante esto, y manteniéndose en su condición, se decide hospitalizar. Durante la hospitalización se prueban distintas fórmulas de administración. Finalmente, se logra respuesta adecuada con LT4 por vía rectal 100 ug/día asociado a 100 ug c/12 horas VO. Discusión: A pesar de no contar con herramientas óptimas para enfrentar este caso, se logró aplicar una estrategia sistemática especializada, que permitió un buen manejo de la paciente. Luego de probar distintas formulaciones de hormonas tiroideas, se logró respuesta mediante la administración por vía rectal, lo cual sugiere que esta paciente presentaba algún trastorno celular/bioquímico intestinal alto, que impedía la absorción óptima de LT4 VO. Conclusiones: La principal fortaleza de este trabajo consiste en la demostración de la utilidad práctica, en un contexto de recursos limitados, de una estrategia de estudio y tratamiento sistemático del hipotiroidismo refractario, lo cual ha sido escasamente publicado en la literatura internacional. Además, se recalca la importancia de una intervención especializada oportuna para evitar los riesgos sistémicos asociados a dosis altas de hormonas tiroideas.

Introduction: Hypothyroidism is a common condition, and its usual treatment is the supplement of oral levothyroxine (po). However, there are unusual cases where it is not possible to correct this condition despite the use of high-dose levothyroxine. Refractory hypothyroidism is defined as the persistence of hypothyroidism despite the use of levothyroxine > 1.9 ug/kg/ day. The prevalence of refractory hypothyroidism has not been sufficiently documented so far. Case description: 53 year old woman with a history of hypothyroidism, obesity, dyslipidemia, hypertension and insulin resistance. She was sent from primary care to tertiary level due to persistent hypothyroidism despite the use of 800 ug/day levothyroxine and liothyronine 80 ug/ day. On an outpatient basis, different causes were excluded as poor adherence to treatment, pseudo-malabsorption, malabsorption syndromes; drug interactions or food interactions. Given this, and staying on her condition, it was decided to hospitalize. Different forms of administration were tested during hospitalization. Finally, got adequate response with levothyroxine rectally 100 ug/day associated with 100 ug po bid. Discussion: Despite not having optimum tools to deal with this case, it was succeeded thanks to the implementation of a specialized systematic strategy. After testing different formulations of thyroid hormones, a positive response by rectal administration was achieved, which suggests that this patient presented any high intestinal cell/biochemist disorder that prevented the optimal absorption of levothyroxine po. Conclusions: The main strength of this work consists in demonstrating the practical utility, in a context of limited resources, of a study and systematic treatment strategy of refractory hypothyroidism, which has barely been published in the international literature. It is also highlighted the importance of an early specialized intervention to prevent the systemic risks associated with high doses of thyroid hormones.

Effect of curcumin in prolonging survival timeof cryopreserved mice via promoting thyroid function / 中国药理学通报

Aim To look for cold-protective drugs treating cryogenic freezing that may bring great damage to animal physiological system.Methods The protective effect of curcumin on frozen damage and the changes of thyroid function in mice were studied in this study.Quantitative analysis of the changes in survival time and metabolic indexes in mice disposed at(-20±1)℃ was conducted.Mouse serum free triiodothyronine(FT3) and free thyroxine(FT4) contents were detected by ELISA kit.HE staining was used to observe thyroid tissue morphological items.The expression of genes related to thyroid function was assessed via real-time quantitative PCR.Results The intraperitoneal injection of curcumin(12.5~50 mg·kg-1) could remarkably prolong the survival time of mice when exposed to cryogenic freezing.HE staining results displayed a recovered thyroid injury in morphology in the curcumin group, further with a notably improved metabolic indexes and evidently increase in serum FT3 and FT4 levels.The real-time quantitative PCR results indicated that the expressions of sodium iodide symporter(Nis), thyroglobulin(Tg) and thyroid peroxidase(Tpo) were up-regulated, and the expression of thyroid-stimulating hormone receptor(Tshr) was down-regulated.Sodium levothyroxine collabrated with the promoting thyroid effects of curcumin, while propylthiouracil inhibited the effects.Conclusion Curcumin can prolong the survival time of the cryogenic freezing mice, which is closely related to its ability to promote thyroid function.