Methimazole plus levothyroxine for treating hyperthyroidism in children: a systematic review and meta-analysis

BACKGROUND

Hyperthyroidism is a disease of excessive synthesis and secretion of thyroid hormones, and there is a lack of studies that have systematically evaluated the efficacy of the combination in treating hyperthyroidism. This study aimed to systematically evaluate the effectiveness and safety of methimazole combined with levothyroxine for treating hyperthyroidism in children.

METHODS

We searched PubMed, CNKI, Wanfang Database, EMBASE, Web of Science, and other online electronic databases to find correlation studies of methimazole combined with levothyroxine in treating hyperthyroidism in children from 2010 to 2021. Meta-analysis was performed using Stata 16 software.

RESULTS

Finally, 15 relevant articles were included comprising 1,718 pediatric patients. Meta-analysis results indicated that compared with methimazole alone (control group), the experimental group administered methimazole + levothyroxine had no evident difference in the level of thyroid-stimulating hormone [standardized mean difference (SMD) =-0.34, 95% confidence interval (CI): -1.02, 0.35, P=0.33], but notably improved the efficacy of clinical treatment of hyperthyroidism in children [odds ratio (OR) =5.77, 95% CI: 2.62, 12.74, P<0.001]. Meanwhile, the experimental group had lower adverse reaction rates (OR =0.28, 95%CI: 0.19, 0.40, P<0.001), free triiodothyronine (FT3) level (SMD =-0.85, 95% CI: -1.57, 0.13, P=0.02), free tetraiodothyronine (FT4) level (SMD =-0.94, 95% CI: -1.59, -0.30, P=0.004) and reduced thyroid volume (SMD =-1.3, 95% CI: -1.67, 0.93, P<0.001).

DISCUSSION

Using methimazole + levothyroxine to treat hyperthyroidism in children can raise the levels of FT3 and FT4, reduce the thyroid volume, improve clinical efficacy, and lower the adverse reaction rate of patients.

Levothyroxine sodium pentahydrate tablets - formulation considerations

Even though levothyroxine sodium pentahydrate tablets have been in the market since 1955, there continue to be recalls due to sub potency. We have comprehensively reviewed the factors affecting its stability in solid oral dosage forms. A compilation of marketed formulation compositions enabled the identification of the potential 'problem excipients'. Two excipient properties, hygroscopicity and microenvironmental acidity, appeared to be responsible for inducing drug instability. In drug products, depending on the formulation composition and storage conditions, the pentahydrate can dehydrate to highly reactive levothyroxine sodium monohydrate, or undergo salt disproportionation to the free acid form of the drug. The USP assay method (HPLC based) is insensitive to these different physical forms of the drug. The influence of physical form of levothyroxine on its chemical stability is incompletely understood. The USP has five product-specific dissolution tests reflecting the complexity in its evaluation.

Thyrotoxicosis after massive triiodothyronine (LT3) overdose: a coast-to-coast case series and review

Excessive exogenous thyroid hormone ingestion may lead to severe thyrotoxicosis and cause potential harm. We have reviewed the literature and suggested that thyroid hormone supplementation should not be used to alleviate nonspecific complaints in patients with normal endogenous thyroid function. Failure to do so may cause serious harm, as demonstrated in one of the cases described here. In addition, treatment based on symptom relief only without biochemical measure may lead to overmedication - as reported from academic hospitals both in Canada and the United States. Given the risk of severe thyrotoxicosis from potential compounding errors, pharmacies providing a compounding service should be subject to more rigorous monitoring by the food and drug administration. Clinicians should also use local biochemical markers when titrating thyroid hormone supplements even though the normal thyroid function reference range has its limitation, failure to do so may result in iatrogenic thyrotoxicosis.

A Practical Forensic Approach to Fatal Pediatric Endocrinopathies

Of all of the organ systems in clinical medicine, the endocrine system is among the most difficult to master since it requires a detailed and knowledgeable integration of many of the body's separate systems. In forensic pathology, the evaluation of a sudden unexplained death can be challenging depending upon the particular disease processes and the organ systems that are affected. It is therefore not surprising that the investigation of sudden unexplained deaths involving the endocrine system can be particularly daunting. This review attempts to focus upon three of the major endocrine/metabolic conditions that may be potentially life-threatening and fatal in the pediatric population - hypoglycemia, adrenal insufficiency, and hyperthyroidism - and to provide forensic pathologists with a practical strategy for working up these cases. By adopting a more focused and selective approach to pediatric endocrine conditions rather than an exhaustive and comprehensive study of them, it is the intention of this review to make these disorders more manageable conceptually and to optimize the chance of arriving at a decisive and ultimately accurate postmortem diagnosis.

Case report: clues to the diagnosis of an unsuspected massive levothyroxine overdose

There is currently little literature pertaining to levothyroxine overdose apart from minor or accidental overdoses in the pediatric population. In particular, there is little information available on how to confidently differentiate levothyroxine overdose from endogenous causes of thyrotoxicosis when there is no history available at the time of assessment. We report a levothyroxine (15,800 mcg) and citalopram (2,460 mg) overdose in a 55-year-old woman presenting with seizure and tachycardia in which the diagnosis was not initially suspected. Clinical data, including a long history of treated hypothyroidism and lack of a goiter; and biochemical findings, such as an incompletely suppressed thyroid-stimulating hormone (TSH) level, despite a markedly elevated free thyroxine level (FT4), a normal sex hormone-binding globulin level at baseline, and an undetectable thyroglobulin, supported the diagnosis of thyrotoxicosis due to a massive exogenous thyroid hormone overdose. Treatment was given to decrease free triiodothyronine (FT3) conversion and increase thyroid hormone clearance with dexamethasone and cholestyramine. The patient made a full recovery. Levothyroxine overdose can result in subtle symptoms and signs clinically, even when in massive quantities. This can make diagnosis challenging. Biochemical features, such as the pattern of thyroid hormone elevation and thyroglobulin levels, help differentiate exogenous thyroid hormone overdose from endogenous causes of thyrotoxicosis.

American Thyroid Association Guide to investigating thyroid hormone economy and action in rodent and cell models

BACKGROUND

An in-depth understanding of the fundamental principles that regulate thyroid hormone homeostasis is critical for the development of new diagnostic and treatment approaches for patients with thyroid disease.

SUMMARY

Important clinical practices in use today for the treatment of patients with hypothyroidism, hyperthyroidism, or thyroid cancer are the result of laboratory discoveries made by scientists investigating the most basic aspects of thyroid structure and molecular biology. In this document, a panel of experts commissioned by the American Thyroid Association makes a series of recommendations related to the study of thyroid hormone economy and action. These recommendations are intended to promote standardization of study design, which should in turn increase the comparability and reproducibility of experimental findings.

CONCLUSIONS

It is expected that adherence to these recommendations by investigators in the field will facilitate progress towards a better understanding of the thyroid gland and thyroid hormone dependent processes.

Thyroid disease in children: part 2 : State-of-the-art imaging in pediatric hyperthyroidism

Hyperthyroidism occurs secondary to overproduction of thyroid hormone by the thyroid gland. This condition can have rather serious effects on children, and thus timely diagnosis and treatment are of utmost importance. Imaging is quite useful in the management of children with hyperthyroidism. In addition to determining the underlying pathology, radiologic exams are crucial for therapy. This article describes the underlying etiologies of pediatric hyperthyroidism and provides general information on treatment.