Recognition and Management of Pediatric Thyroid Emergencies in the Emergency Department

Table of Contents

 

Thyroid disease can be difficult to diagnose in the ED, not only because it is uncommonly seen, but because the variety of presentations is wide. Nonetheless, the ED provides an ideal setting to diagnose and arrange for treatment of thyroid disease. This issue reviews common presentations of various thyroid diseases and provides evidence-based recommendations for the management of patients with these diseases. You will learn:

Causes of hypothyroidism and hyperthyroidism

Common manifestations of hypothyroidism, myxedema coma, hyperthyroidism, Graves disease, thyroid storm, thyroid nodules, and thyroid trauma

When additional testing beyond TSH, T4, and T3 is necessary, and which tests are recommended for identifying different thyroid disorders

Management of patients with myxedema coma, thyroid storm, and thyroid trauma

Which patients can be discharged with referral for further evaluation and treatment, and which patients need surgical consultation or admission

1. Abstract
2. Case Presentations
3. Introduction
4. Critical Appraisal of the Literature
5. Etiology and Pathophysiology
6. Differential Diagnosis
   1. Hypothyroidism
      1. Congenital Hypothyroidism
      2. Acquired Hypothyroidism
      3. Myxedema Coma
   2. Hyperthyroidism
      1. Thyroid Storm
   3. Thyroid Nodules
      1. Trauma to the Thyroid Gland
7. Prehospital Care
8. Emergency Department Evaluation
   1. Hypothyroidism
   2. Hyperthyroidism
   3. Thyroid Storm
   4. Thyroid Nodules
9. Diagnostic Studies
   1. Hypothyroidism and Hyperthyroidism
   2. Thyroid Storm
   3. Myxedema Coma
   4. Thyroid Nodules
10. Treatment
    1. Myxedema Coma
    2. Thyroid Storm
    3. Thyroid Trauma
    4. General Management of Patients With Thyroid Disease
11. Special Circumstances
    1. Congenital Hypothyroidism
       1. Diagnosis
       2. Treatment
    2. Thyroid Disease and Pregnancy
    3. Exposure to Ionizing Radiation
    4. Pre-Existing Thyroid Disease
12. Controversies and Cutting Edge
    1. Subclinical Hypothyroidism
       1. Subclinical Hypothyroidism in Pregnancy
    2. Thyroid Storm and Levocarnitine
    3. Thyroid Nodules
    4. Desiccated Thyroid Hormone Versus Levothyroxine
13. Disposition
14. Summary
15. Risk Management Pitfalls in the Management of Pediatric Patients With Thyroid Disease
16. Case Conclusions
17. Time- and Cost-Effective Strategies
18. Clinical Pathways
    1. Clinical Pathway for the Management of Suspected Hypothyroidism
    2. Clinical Pathway for the Management of Suspected Hyperthyroidism
19. Tables and Figures
    1. Table 1. Manifestations of Hypothyroidism and Hyperthyroidism
    2. Table 2. Causes of Acquired Hypothyroidism in Children
    3. Table 3. Causes, Pathophysiologic Features, and Frequency of Various Types of Hyperthyroidism
    4. Table 4. Dosage Information for Medications Used to Treat Thyroid Storm
    5. Figure 1. Thyroid Hormone Feedback Loops
20. References

Abstract

The wide range and vague nature of clinical presentations of thyroid emergencies make accurate and timely diagnosis challenging. Patients with a variety of thyroid conditions present to the emergency department, and appropriate suspicion can reduce unnecessary delay and expense in determining the correct diagnosis. This issue reviews the current evidence for presentation, evaluation, and treatment for emergencies of thyroid function and anatomy including hypothyroidism, hyperthyroidism, thyroid nodules, and thyroid trauma. Complications of thyroid dysfunction are also considered, as well as recommendations for disposition and follow-up.

Case Presentations

A 4-year-old boy presents to your ED, asymptomatic after suspected ingestion of 25 tablets of his grandmother’s 300-mcg levothyroxine. The ingestion occurred 90 minutes ago. You wonder: Is this amount toxic? Would serum hormone levels be helpful? What symptoms would be concerning? How should this patient be managed?

An 8-year-old boy with a history of Down syndrome is brought in by his parents because he is lethargic. He is difficult to rouse and has a history of vomiting and diarrhea for the last 4 days. His parents say this is very unusual for him, as he is usually constipated. The boy responds slowly to voice and shows signs of dehydration on examination. His mucous membranes are tacky, his capillary refill is 4 seconds, and he has cool extremities. The patient’s heart rate is 135 beats/min and his blood pressure is 100/60 mm Hg. A review of systems reveals no recent weight change, no unusual hair growth, and no temperature intolerance. In the waiting room, oral rehydration by syringe has been unsuccessful. While you suspect that dehydration is the cause of this patient's condition and begin to calculate fluid replacement, you recall that constipation can be a symptom of thyroid disease. Should you check the patient's thyroid stimulating hormone level while you start intravenous rehydration?

A 16-year-old adolescent girl is brought in by EMS for reported mania. According to her parents, she has been a good student, with no history of drug use. Her initial vital signs are: temperature, 38.9°C (102°F); heart rate, 120 beats/min; respiratory rate, 16 breaths/min; and blood pressure, 140/80 mm Hg. The patient is sweaty, pale, thrashing, and speaking rapidly and incomprehensibly. As you prepare to draw initial laboratory samples, you wonder if this could be a manifestation of hyperthyroidism, and whether drawing samples for thyroid stimulating hormone testing is appropriate. How will you manage this patient if there is evidence of thyrotoxicosis? Will it change your initial medications for treatment of the agitated patient? Are there important findings on other tests you need to watch for?

Introduction

Thyroid disease is a common health problem in the population at large, but it does not often present to the emergency department (ED) as a primary concern. Thyroid disease is less common in children than adults. A Scottish population-based study found the prevalence of hypothyroidism to be 0.135% among all residents aged < 22 years. Of affected patients, 73% had acquired hypothyroidism, 66% of which had an autoimmune basis.¹ In areas with screening programs, patients with congenital hypothyroidism are usually identified in the neonatal period; however, this condition may present later in infancy if screening was not performed or in children with diets low in iodine.

For an emergency clinician, thyroid disease is often difficult to diagnose, not only because it is uncommon, but because the signs and symptoms are vague and nonspecific and the variety of presentations is wide. This often leads to a delay in diagnosis. Two separate chart reviews^2,3 demonstrated that children who were ultimately diagnosed with hyperthyroidism underwent testing for symptoms related to behavior (eg, attention deficit-hyperactivity disorder) or cardiac symptoms, were referred for non–endocrine subspecialist assessments 22.4% of the time, and underwent diagnostic testing and procedures costing as much as $14,000 per patient before their thyroid disease was confirmed.

Nonetheless, the ED provides an ideal setting to diagnose and arrange for treatment of thyroid disease. A fresh look at symptoms and signs, the availability of diagnostic testing, and access to pediatric subspecialists for follow-up makes thyroid disease relatively simple to diagnose and treat. Because of the severity of symptoms that can develop, the ED is also the site where acute thyrotoxicosis due to endogenous or exogenous hormone is most likely to present. This issue of Pediatric Emergency Medicine Practice reviews common presentations of various thyroid diseases and provides evidence-based recommendations for the management of patients with these diseases.

Critical Appraisal of the Literature

A literature search for articles published from 1990 to the present was performed in PubMed using the terms child, guidelines, thyroid emergencies, hypothyroid, hyperthyroid, thyroid trauma, and thyroid nodule. In addition, the Cochrane Database of Systematic Reviews was searched for reviews related to pediatric thyroid disease.

Recent high-level evidence for most thyroid disease is difficult to find. New evidence in the last 25 years is restricted to reviews, case reports, small studies, and clinical practice guidelines based on older evidence. Recent guidelines exist for the diagnosis and management of thyroid nodules,^4,5 congenital hypothyroidism,^6,7 childhood hypothyroidism,^8,9 hyperthyroidism,¹⁰ and Graves disease.¹¹

Risk Management Pitfalls in the Management of Pediatric Patients With Thyroid Disease

6. “My patient ingested a family member's thyroid medicine. I checked his thyroid levels when he came in, and they were normal. I don't understand how he got so much worse overnight.”

Young children are at risk for thyrotoxicosis from ingestion of levothyroxine, but usually do not show symptoms at the index visit. Ensure that repeat clinical assessments and laboratory evaluations are performed in follow-up.

7. “I gave acetaminophen to my patient with thyroid storm, but she just kept getting warmer and acting sicker!”

Propranolol and external cooling are the mainstays of ED treatment for thyroid storm. Antipyretics are of uncertain benefit, and salicylates in particular are contraindicated, as they may increase free thyroid hormone levels.

8. “Last week I saw a boy with recently diagnosed attention-deficit/hyperactivity disorder. He just had behavioral complaints, so I sent him home. He came back and was diagnosed with thyroid disease!”

Strongly consider evaluating TSH levels in patients with new behavioral complaints, unexplained cardiac complaints, or slipped capital femoral epiphysis.

Tables and Figures

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of patients. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study is included in bold type following the reference, where available. In addition, the most informative references cited in this paper, as determined by the author, are highlighted.

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