A newborn by normal vaginal delivery is brought for routine screening. you found an increase in TSH and low thyroxine T4. Apgar scores were 8 and 9 at 1 and 5 minutes, respectively. Physical examination reveals a normal size of the thyroid gland in the normal position. Neck ultrasound confirms an ectopic thyroid tissue beloww tounge . Which of the following is the most likely cause of this patient's otherwise normal physical examination despite abnormal thyroid laboratory findings?

Question

Quizplus · Accepted Answer

Eductional Objective: Congenital hypothyroidism, most commonly caused by abnormal thyroid gland development or location (ie, ectopy), is identified by elevated TSH and decreased thyroxine (T4) levels.  Clinical manifestations of hypothyroidism are not present at birth due to the transplacental transfer of small amounts of maternal T4.

A Newborn by Normal Vaginal Delivery Is Brought for Routine