Does clinical management impact height potential in children with severe acquired hypothyroidism?

The association between perchlorate in drinking water and height and weight of children and adolescents in Southwest China: a retrospective cross-sectional study

Objective

To investigate the association between the concentration of perchlorate in drinking water and the height and weight of children and adolescents in Sichuan Province.

Methods

Perchlorate in the drinking water of 24 counties in Sichuan Province from 2021 to 2022 was detected and analyzed, 66 drinking water samples were collected, and the content of perchlorate in drinking water during the wet season and dry season was detected by ultra-high performance liquid chromatography in series. The linear mixed effect model was used to estimate the relationship between perchlorate in drinking water and the height and weight of 144,644 children and adolescents, and 33 pieces of local average wage data were used as confounding factors for quality control.

Results

After controlling the age, gender, and local economic situation, we found that the concentration of perchlorate in drinking water increased by 10 μg/L is associated with a 1.0 cm decrease in height and a 1.6 kg decrease in weight in children and adolescents (p < 0.05).

Conclusion

The concentration of perchlorate in drinking water may be negatively correlated with the height and weight of children.

Pituitary Macroadenoma Secondary to Congenital Hypothyroidism With Growth Failure and Developmental Delay: A Rare Presentation

Reactive pituitary hyperplasia can develop as a pituitary (pseudo) macroadenoma in the case of primary hypothyroidism. Hypothyroidism-induced pituitary hyperplasia (PHPH) can be managed medically. Surgery should not be performed if this condition is misdiagnosed as an adenoma. Primary hypothyroidism is a well-known cause of children's slow linear growth. Anterior pituitary enlargement is a rare symptom of severe or long-term illness (pituitary pseudotumor). Thyroid-stimulating hormone-secreting adenomas (TSHomas) are the rarest type of pituitary adenomas, with most endocrinologists seeing just a few cases throughout their lives. In most situations, the diagnosis is difficult, and patients may be referred after presenting with a condition of excessive thyroid-stimulating hormone secretion or a pituitary tumor. In this case study, we describe a 3.5-year-old girl who was referred to our hospital for a surgical assessment of a suspected pituitary neoplastic lesion. It was later determined that the suspected lesion was really pituitary hyperplasia brought on by primary hypothyroidism. Levothyroxine was started, and the dose was increased. The patient was advised to follow up to see if pituitary macroadenoma had responded to levothyroxine supplementation. Pituitary enlargement (pseudotumor of the pituitary gland) is a rare complication of primary hypothyroidism. Early diagnosis and treatment are critical for children with severe primary hypothyroidism to maintain their final height, as late diagnosis nearly always leads to a decline in adult stature. Pituitary macroadenoma secondary to severe hypothyroidism does not need risky and expensive surgical intervention. Because PHPH is rare in children, more credible information is needed to have a better knowledge of how the disease progresses and to develop scientific diagnostic criteria.

Evaluation of catch-up growth in severe pediatric Hashimoto's hypothyroidism

BACKGROUND

We aimed to evaluate catch-up growth in children with severe Hashimoto's hypothyroidism (HH) after thyroid hormone replacement therapy (HRT).

METHODS

A multicenter retrospective study was conducted including children referred for growth slowdown that led to the diagnosis of HH between 1998 and 2017.

RESULTS

A total of 29 patients were included, with a median age of 9.7 years (13-172 months). Median height at diagnosis was -2.7 [-4.6; -0.1] standard deviation score (SDS), with a height loss of 2.5 [0.7; 5.4] SDS compared to height before growth deflection (p<0.0001). At diagnosis, the median TSH level was 819.5 mIU/L [100; 1844], the median FT4 level was 0 pmol/L [undetectable; 5.4], and the median anti-thyroperoxidase antibody level was 1601 UI/L [47; 25,500]. In the 20 patients treated only with HRT, there were significant differences between height at diagnosis and height at 1 year (n = 19, p<0.0001), 2 years (n = 13, p = 0.0005), 3 years (n = 9, p = 0.0039), 4 years (n = 10, p = 0.0078), and 5 years (n = 10, p = 0.0018) of treatment but not in the case of final height (n = 6, p = 0.0625). Median final height was -1.4 [-2.7; 1,5] SDS (n = 6), with a significant difference between height loss at diagnosis and total catch-up growth (p = 0.003). The other nine patients were also given growth hormone (GH). They were smaller at diagnosis (p = 0.01); however, there was no difference in final height between those two groups (p = 0.68).

CONCLUSION

Severe HH can lead to a major height deficit, and catch-up growth seems to be insufficient after treatment with HRT alone. In the most severe cases, administration of GH may enhance this catch-up.

Pediatric Myxedema Due to Autoimmune Hypothyroidism: A Rare Complication of a Common Disorder

In children, hypothyroidism usually presents non-specific symptoms; symptoms can emerge gradually, compromising a timely diagnosis. We report the case of a 13-year-old male, who was admitted to the hospital due to swelling of the torso and neck. Besides these symptoms, the child was healthy, except for a significant growth delay. Ultrasound evaluation and blood tests led to the diagnosis of myxedema secondary to severe hypothyroidism, which was due to autoimmune thyroiditis. Further investigations revealed pericardial effusion and pituitary hyperplasia, with hyper-prolactinemia. Treatment with levothyroxine led to edema regression and clinical, hemato-chemical and radiological improvement. After 6 months, growth velocity increased, although the recovery of growth already lost was not guaranteed. Brain MRI showed regression of pituitary hyperplasia. The diagnostic delay in this case was probably due to the patient's apparent good health, and the underestimation of growth restriction. This report underlines the importance of growth monitoring in adolescence, a critical period for identifying endocrine conditions; if undiagnosed, these conditions can lead to serious complications, such as myxedema in hypothyroidism, with potential effects beyond growth on multiple organs.

Anastrozole Improves Final Adult Height in Severe Hypothyroidism With Rapid Pubertal Progression

Severe prolonged hypothyroidism due to Hashimoto thyroiditis may lead to rapid pubertal progression and compromised adult height after initiation of levothyroxine (LT4) therapy. There are no reports of aromatase inhibitor use to augment height in these patients. We describe a patient with severe hypothyroidism and growth failure who experienced rapid pubertal and bone age maturation on initiation of LT4 therapy. Anastrozole was added after 2 years to delay epiphyseal fusion. A boy aged 12 years and 1 month presented to the endocrine clinic with short stature and a markedly delayed bone age of 6 years. Brain magnetic resonance imaging showed a 1.5 × 1.0 × 1.2-cm enlarged lobular anterior pituitary. On examination, his height was -3.5 SD score (SDS) and weight was -2.87 SDS. Laboratory studies showed elevated thyrotropin (TSH) 850.6 μIU/mL, low free thyroxine 0.25 ng/dL, and elevated antithyroid antibodies. LT4 was initiated with normalization of TSH after 6 months. After 2 years of treatment he demonstrated catch-up growth with rapid bone age maturation, and his predicted adult height was compromised at 164.6 cm vs a midparental target height of 175.4 cm. Anastrozole 1 mg once daily was initiated. After 1.5 years of anastrozole treatment, the rate of his bone age advancement had slowed and his linear growth remained robust. The patient's near-final height (167 cm) was 2.4 cm taller than his height prediction prior to starting anastrozole. Anastrozole slowed the rate of bone age advancement in a patient with severe hypothyroidism and rapidly progressive puberty during treatment with LT4, leading to improvement in near-final height.

Thyroid hormone therapy in congenital hypothyroidism and pediatric hypothyroidism

The evaluation and management of hypothyroidism in children are similar to adults, but there are important differences based on the dependence on normal thyroid function for neurocognitive and physical development. In the pediatric population, hypothyroidism is frequently categorized as congenital or acquired hypothyroidism, depending on the age of presentation and the underlying etiology. The evaluation and management of children and adolescents with hypothyroidism are determined by the etiology as well as by the age at diagnosis, severity of the hypothyroidism, and the response to thyroid hormone replacement therapy. Children and adolescents require higher weight-based doses for thyroid hormone replacement than do adults, likely due to a shorter half-life of thyroxine (T4) and triiodothyronine (T3) in children, but weight-based dose requirements decrease as the child advances into adulthood. Multiple gaps in knowledge remains regarding how to optimize the treatment of hypothyroidism in pediatric patients, including (but not limited to) the selection of patients with subclinical hypothyroidism for treatment, and the potential benefit of combined LT3/LT4 therapy for patients with persistent symptoms and/or low T3 on LT4 monotherapy. The life-long impact on growth and development, and potentially on long-term cardiovascular and psychosocial health, are significant and highlight the importance of future prospective studies in pediatric patients to explore these areas of uncertainty.

Determinants of levothyroxine dose required to achieve euthyroidism in pediatric population-a hospital-based prospective follow-up study

We analyzed the relation of pretreatment anthropometric measures and serum thyrotropin (TSH) with the levothyroxine requirement. Children (3-18 years) brought to endocrine clinic with newly diagnosed acquired primary hypothyroidism were enrolled consecutively and prospectively with follow-up (July 2014 to April 2016). Children were started on levothyroxine, and dose was adjusted at regular intervals until achieved euthyroidism (serum TSH 0.4 to 4.5 mIU/L). The relationship of age, gender, height, weight, and serum TSH with levothyroxine dose was analyzed by univariate and multivariate regression analysis. Data of 51 children (42 girls and 9 boys) was used for the analysis. Age, weight, height, and serum TSH had significant correlation with levothyroxine daily dose based on weight (D/W) and dose based on BSA (D/BSA). Log₁₀ TSH and gender explained ∼60% absolute levothyroxine daily requirement. The final model built with height and serum TSH predicted ∼85% of D/W and ∼80% of D/BSA.

CONCLUSION

Pretreatment height and serum TSH can be used to determine levothyroxine dose needed to achieve euthyroidism in a newly diagnosed acquired primary hypothyroidism in children. What is Known: • The starting dose of levothyroxine is currently recommended based on the age of children. What is New: • In pediatric population, the effect of age on levothyroxine daily dose requirements can be explained by pretreatment height. • Pretreatment serum TSH level is an important predictor of levothyroxine daily dose in children with newly diagnosed primary hypothyroidism.

Massive pericardial effusion and short stature caused by autoimmune hypothyroidism in a 9-year-old girl

A 9-year-, 11-month-old girl was brought to the Emergency Department for sudden dyspnea caused by massive pericardial effusion. In addition to relative bradycardia despite impending cardiac tamponade, short stature, overweight, and hypercholesterolemia were clues for suspected hypothyroidism. During thyroxine supplementation, catch-up growth was incomplete by rapid skeletal maturation. The use of short-term growth hormone showed increased growth velocity. In conclusion, primary hypothyroidism should be included in the etiologic evaluation of pericardial effusion, especially when it is associated with relative bradycardia. Additional growth promoting therapy should be considered for incomplete catch-up growth in prolonged hypothyroidism during thyroxine supplementation.

Guidelines for the treatment of hypothyroidism: prepared by the american thyroid association task force on thyroid hormone replacement

BACKGROUND

A number of recent advances in our understanding of thyroid physiology may shed light on why some patients feel unwell while taking levothyroxine monotherapy. The purpose of this task force was to review the goals of levothyroxine therapy, the optimal prescription of conventional levothyroxine therapy, the sources of dissatisfaction with levothyroxine therapy, the evidence on treatment alternatives, and the relevant knowledge gaps. We wished to determine whether there are sufficient new data generated by well-designed studies to provide reason to pursue such therapies and change the current standard of care. This document is intended to inform clinical decision-making on thyroid hormone replacement therapy; it is not a replacement for individualized clinical judgment.

METHODS

Task force members identified 24 questions relevant to the treatment of hypothyroidism. The clinical literature relating to each question was then reviewed. Clinical reviews were supplemented, when relevant, with related mechanistic and bench research literature reviews, performed by our team of translational scientists. Ethics reviews were provided, when relevant, by a bioethicist. The responses to questions were formatted, when possible, in the form of a formal clinical recommendation statement. When responses were not suitable for a formal clinical recommendation, a summary response statement without a formal clinical recommendation was developed. For clinical recommendations, the supporting evidence was appraised, and the strength of each clinical recommendation was assessed, using the American College of Physicians system. The final document was organized so that each topic is introduced with a question, followed by a formal clinical recommendation. Stakeholder input was received at a national meeting, with some subsequent refinement of the clinical questions addressed in the document. Consensus was achieved for all recommendations by the task force.

RESULTS

We reviewed the following therapeutic categories: (i) levothyroxine therapy, (ii) non-levothyroxine-based thyroid hormone therapies, and (iii) use of thyroid hormone analogs. The second category included thyroid extracts, synthetic combination therapy, triiodothyronine therapy, and compounded thyroid hormones.

CONCLUSIONS

We concluded that levothyroxine should remain the standard of care for treating hypothyroidism. We found no consistently strong evidence for the superiority of alternative preparations (e.g., levothyroxine-liothyronine combination therapy, or thyroid extract therapy, or others) over monotherapy with levothyroxine, in improving health outcomes. Some examples of future research needs include the development of superior biomarkers of euthyroidism to supplement thyrotropin measurements, mechanistic research on serum triiodothyronine levels (including effects of age and disease status, relationship with tissue concentrations, as well as potential therapeutic targeting), and long-term outcome clinical trials testing combination therapy or thyroid extracts (including subgroup effects). Additional research is also needed to develop thyroid hormone analogs with a favorable benefit to risk profile.

Primary hypothyroidism with growth failure and pituitary pseudotumor in a 13-year-old female: a case report

Introduction

Primary hypothyroidism is a well-known cause of poor linear growth in children. A rare finding with profound or long-standing disease is anterior pituitary enlargement (pituitary pseudotumor). This case highlights this uncommon finding, discusses clinical situations in which gradual dose escalation of levothyroxine may be advisable and reviews adjuvant therapies that have been previously attempted to improve final height in the setting of profound hypothyroidism.

Case presentation

We report the case of a 13-year-old Hispanic girl initially evaluated for poor linear growth and delayed puberty, and found to have pituitary enlargement secondary to profound primary hypothyroidism. Treatment with progressive doses of levothyroxine normalized her symptoms and led to complete resolution of her pituitary findings, but she then rapidly progressed through puberty, achieving an adult height of only 142cm, significantly below her calculated mid-parental height.

Conclusions

In cases of severe primary hypothyroidism with prolonged elevation of thyroid-stimulating hormone and pituitary pseudotumor, gradual replacement of thyroid hormone with slowly escalating doses of levothyroxine may be beneficial to prevent complications of therapy. Early recognition and treatment of hypothyroidism during childhood is essential for normal growth, as final height is invariably compromised in children with prolonged disease. Additional study is needed to determine the potential beneficial effects of gonadotropin-releasing hormone agonist and recombinant human growth hormone treatment in this setting.

Incidence and characteristics of pseudoprecocious puberty because of severe primary hypothyroidism

Severe primary hypothyroidism is a presumed rare cause of pseudoprecocious puberty (PsPP). Here, we report a 24% incidence of PsPP among 33 children with profound hypothyroidism. Those with PsPP were older and trended toward a higher thyroid stimulating hormone. Increased awareness of PsPP can hasten diagnosis and appropriate treatment.