Neonatal Nurse Practitioner Practice Exam

If a neonate has a low T4 and elevated TSH, what should be the appropriate next step?

1. Begin thyroid hormone replacement therapy

2. Monitor the infant for lethargy, hypotonia and feeding difficulties

3. Recheck T4 and TSH levels at two months of age

4. Refer to an endocrinologist

The correct answer is: Begin thyroid hormone replacement therapy

In the case of a neonate presenting with low T4 and elevated TSH levels, this scenario is indicative of primary congenital hypothyroidism. The elevated TSH suggests that the pituitary gland is producing more thyroid-stimulating hormone in response to low levels of thyroid hormone (T4), which occurs when the thyroid gland is underactive or not functioning correctly. The immediate and appropriate intervention for congenital hypothyroidism is to initiate thyroid hormone replacement therapy. Thyroid hormone is critical for the normal growth and development of a neonate, particularly for brain development, and a delay in treatment can lead to serious long-term developmental issues, including intellectual disabilities. Starting therapy quickly can help mitigate the risk of these adverse outcomes, making it the most essential step in managing this condition. Monitoring for symptoms, rechecking hormone levels, or referring to an endocrinologist may be valid in certain contexts, but they do not address the urgent need for treatment and could result in harms due to an avoidable delay in starting necessary therapy. Thus, beginning thyroid hormone replacement therapy is the correct and most immediate course of action in this situation.