Myxedema Coma due to Hashimoto Thyroiditis: A Rare but Real Presentation of Failure to Thrive in Infancy

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.

Myxedema crisis and ovarian hyperstimulation in a child with Down syndrome

OBJECTIVES

Myxedema crisis, a fatal complication of severe hypothyroidism, is extremely rare in children and treatment guidelines are lacking. Since availability of intravenous levothyroxine is limited in resource poor settings, myxedema crisis can be treated with oral levothyroxine and/or oral liothyronine (if necessary), in the absence of cardiac risk factors, thus hastening the recovery and significantly decreasing the associated morbidity and mortality. In the background of untreated hypothyroidism, a possible association of ovarian hyperstimulation syndrome (OHSS) and reactive pituitary hyperplasia should be kept in mind, thus preventing unnecessary interventions.

CASE PRESENTATION

A 13-year-old girl child with Down syndrome, presented with myxedema crisis, as initial presentation of untreated hypothyroidism.

CONCLUSIONS

Annual screening, timely diagnosis of hypothyroidism, and early initiation of thyroid hormone supplementation will prevent associated physical and neurocognitive morbidity in children, especially those with Down syndrome. Importance of oral liothyronine supplementation in myxedema crisis, has been highlighted in this case report.

Clinical Characteristics and Follow-Up of 19 Children With Hashimoto's Thyroiditis Aged Below 3 Years: A Single-Center Retrospective Analysis

AIM

To analyze the clinical characteristics of Hashimoto's thyroiditis (HT) in children below 3 years of age in order to improve the understanding of the disease, avoid misdiagnosis, and achieve early diagnosis and treatment.

METHODS

The study retrospectively analyzed the clinical data of 19 patients diagnosed with HT in the first three years of life.

RESULTS

The patients (12 female, 7 male) had an average age of 26.1 ± 8.2 months (range 10-36 months). At presentation, one patient had euthyroidism, ten had hypothyroidism, seven had subclinical hypothyroidism, and one had hyperthyroidism. The most common reasons for doctor's visits were thyroid enlargement (21.1%), global developmental delay (21.1%), and routine thyroid function tests in patients with type 1 diabetes (26.3%). Sixteen patients provided follow-up data, and the mean follow-up time was 23.31 ± 16.44 months (range 1-48 months). In the hypothyroidism group, one patient stopped levothyroxine (LT4) treatment after 2 months; the remaining patients had been treated with LT4 since their diagnosis. In the subclinical hypothyroidism group, one patient whose thyroid function returned to normal after 1 month of being diagnosed was not treated. The remaining patients received LT4 treatment at their diagnosis or during follow-up. The patient with hyperthyroidism was treated with methimazole after diagnosis, but treatment was discontinued 11 months later and LT4 was initiated 26 months after diagnosis. One in four patients with global developmental delay approached normal mental development after LT4 treatment. Four in six patients with short stature achieved height catch-up.

CONCLUSION

At their initial HT diagnosis, most of the children showed hypothyroidism or subclinical hypothyroidism. Children with global developmental delay require continual screening, even if the thyroid function is normal after birth, to determine whether they have HT-induced hypothyroidism. Thyroxine replacement could partially relieve the clinical manifestations of hypothyroidism and early diagnosis and treatment are essential for improving patient prognosis.