Brief Answer:
About thyroid nodules;

Detailed Answer:
Hello and thank you for asking!
I can understand your concern regarding to your son's health.
Ultrasound of the thyroid gland gives very useful information regarding to nodule's characteristics.
If they have pure cystic nature than they are considered benign and the next step would be the evaluation of the thyroid function ( TSH level).
If one of them has 2 or more suspicious characteristics in ultrasound (irregular borders, high vascularisation, hypoechogen, microcalcification, taller than wider)TSH level and than Fine needle aspiration is recommended.
As you described, they seem to be cysts ( except to one in istmus that is not described further) there is no need to get worried.
Anyway, your physician will guide you further having into consideration the physical examination history of the disease, family predisposition ect.
Hope the information will help.
Kind regards,
Dr.Mirjeta

---

Brief Answer:
About thyroid nodules;

Detailed Answer:
Welcome back,
At this age they may shrink or disappear with levothyroxine therapy ( if the thyroid hormones are within the normal level).
Usually there is a genetical predisposition for cysts or nodules in the thyroid gland.
Probably you/ your husband or other ancestors have nodular goiter.
Nodules are very common in the general population, 1 in 2 persons have nodules in ultrasound.
So, ia not a rare pathology.
Will be a pleasure to help you further.
Kind regards,
Dr.Mirjeta

---

Brief Answer:
Check the thyroid function:

Detailed Answer:
Welcome back,
The thyroid gland volume is not increased and the nodules are to small to compress the trachea and cause cough or shortness of breath.
Anyway the thyroid function should be checked to rule out on over active thyroid that may cause tachychardia and shortness of breath due to it.
Wish him good health.
Kind regards,
Dr.Mirjeta

---