Which clients are at risk for hypothyroidism: a middle-aged adult with osteoarthritis, a child born with DiGeorge syndrome, an older adult who underwent a thyroidectomy (surgical removal of the thyroid gland) two years ago, or a young adult diagnosed with Addison's disease (primary adrenal insufficiency)?

Risk Factors for Hypothyroidism

The client at highest risk for hypothyroidism is the older adult who underwent a thyroidectomy two years ago, as surgical removal of the thyroid gland directly causes hypothyroidism requiring lifelong thyroid hormone replacement therapy. 1

Analysis of Risk Factors by Patient

Older Adult Post-Thyroidectomy

• Highest Risk: Surgical removal of the thyroid gland (thyroidectomy) results in permanent hypothyroidism in nearly all cases
• Total thyroidectomy leads to the inability to produce thyroid hormones, necessitating lifelong thyroid hormone replacement therapy 1
• Postoperative levothyroxine is indicated for all patients who undergo thyroidectomy 1
• The most common significant complications of thyroidectomy include hypoparathyroidism and recurrent laryngeal nerve injury 1

Child with DiGeorge Syndrome

• Moderate-High Risk: DiGeorge syndrome (22q11.2 deletion) is associated with endocrinopathies including hypothyroidism
• Nearly 1 in 4 patients with 22q11.2 deletion syndrome require treatment for primary hypothyroidism 1
• Onset of hypothyroidism occurs decades earlier than in the general population 1
• Thyroid function should be assessed annually in patients with DiGeorge syndrome 1
• Children with DiGeorge syndrome should have early newborn thyroid screening due to the higher risk of hypothyroidism 2

Young Adult with Addison's Disease

• Low-Moderate Risk: While not directly causative, there is an association between autoimmune disorders
• Addison's disease (primary adrenal insufficiency) is an autoimmune condition that can be associated with other autoimmune disorders including autoimmune thyroiditis
• However, this association is not as direct or common as the risk following thyroidectomy or with DiGeorge syndrome

Middle-aged Adult with Osteoarthritis

• Lowest Risk: No established direct connection between osteoarthritis and hypothyroidism
• Osteoarthritis is not listed as a risk factor for thyroid dysfunction in clinical guidelines 1

Radiology Technologist in Trauma Center

• Low Risk: Occupational exposure to radiation in properly protected healthcare workers is generally not sufficient to cause thyroid dysfunction
• While high levels of radiation exposure (>20 mGy) are considered a risk factor for thyroid dysfunction 1, radiology technologists typically work with appropriate protective equipment

Clinical Considerations

Monitoring and Management

• Post-thyroidectomy patients require regular monitoring of thyroid function tests to ensure adequate hormone replacement 1
• TSH should be kept in the normal range through adjusting the levothyroxine dose 1
• Liothyronine (T3) can be used in patients allergic to other thyroid preparations 3

Common Pitfalls

1. Failure to recognize hypothyroidism in DiGeorge syndrome: Symptoms may be attributed to the syndrome itself rather than to thyroid dysfunction 1, 2
2. Inadequate monitoring post-thyroidectomy: Insufficient follow-up can lead to under-replacement or over-replacement of thyroid hormone
3. Overlooking hypomagnesemia: Severe hypomagnesemia can cause functional hypoparathyroidism, leading to hypocalcemia 4
4. Missing concomitant autoimmune disorders: Patients with one autoimmune disorder (like Addison's disease) should be monitored for development of others

Special Considerations for DiGeorge Syndrome

• Patients with DiGeorge syndrome may develop both hypoparathyroidism and hypothyroidism 5
• Regular calcium, parathyroid hormone, magnesium, and thyroid-stimulating hormone monitoring is recommended 1
• These patients may also develop autoimmune thyroid disorders including Graves' disease despite the immune deficiency associated with the syndrome 6, 7