What is the Harm of Switching Brands of LT4?

A Rare Thyroid Disease in A Teenager

I recently saw a 17 year old high school student, and it reminded me of a patient I saw a few years ago with a similar problem. He had thyroid nodule 3 years before I first saw him. His Pediatrician sent him to see a pediatric endocrinologist. All thyroid tests were normal,except the TSH was slightly low. The Thyroid scan showed a "hot" Nodule, with suppressed thyroid uptake on the other side.The 6/24 HR uptakes were normal.He was followed 3 times a year. The nodule increased in size, the TSH decreased, and the T3 increased, but still in the normal range. Because the T3 was still normal, inspite of significant decrease in TSH, there was no therapy given. Finally, one year later the T3 was abnormally elevated.
The TSH was very low. He had increased resting heart rate in the 90's. Again, there was no therapy for hyperthyroidism offered. He was seen again 5 months later, and the again the tests clearly confirm T3 Toxicosis. They considered surgery vs. radioiodine, but deferred to an adult endocrinologist. The reason they gave was they were not used to treating a teenager with Toxic Nodule, just Graves' Disease.
There was no anti-thyroid drug, or beta blocker given. The tests again showed T3 toxicosis at the second opinion 4 months later. The recommendation was for surgery, but no therapy was offered. 3 months later he was still untreated, and referred to me.
He was 17. School grades were poor. He had poor concentration, and memory problems.He had sweats, felt jittery, and had palpitations, and lost 12 pounds from his normal weight.Also had symptoms of hypoglycemia, without diabetes. Mentally, He had nightmares, a short temper,and felt very tense.
PE: WT loss 12 LBS, BP 110/60 P 130 regular
With mild exercise up stairs the pulse increased to 180. Proximal muscle weakness, and a large visible mass on the right side of his neck. The U.S. showed a 5 cm mixed mass. It was 2.5 cm larger that 3 years ago. in benign thyroid nodules.The scan confirmed a hot nodule. The I/123 uptake was elevated at 60 % N 8-32%. My testing confirmed hyperthyroidism secondary to a toxic nodule. This is rare in teenagers. The T3 was elevated, TSH was non-detectable, and the T4 was upper normal.
He finally had surgery after 6 weeks, when he was euthyroid. He is doing well in college now.


The time between childhood and adulthood, can be a wasteland for teenage thyroid patients. His health, and schooling suffered because he had a rare disease, Toxic Nodule in childhood, which is common in older adults.There was never any therapy given to combat his hyperthyroidism, and only a plan for definitive surgery, or radioiodine was offered. He needed to be rendered euthyroid before surgery anyway, and even probably before radioiodine. Surgery is the therapy of choice for a teenager. A more rapid referral to adult endocrinologist, who is used to treating toxic nodules in the adult population, may have saved 2 years of reduced health and poor school grades.

DR.G.

They Changed Your T4 Brand at the Pharmacy. What happens to your health?

A Pharmetrics study of 196 patients who were switched to a different T4 brand, but at the same dose. Prior to the switch, the titration blood studies confirmed they all had normal TSH.

Results:

1. 35% had a change of TSH of less than 0.5. This may not be important, unless the patient had cancer, were even that small change could stimulate cancer cell growth. Also T4 suppression therapy for goiters may be impacted.

2. 20% had a change of TSH of 0.5-1.0. Again not bad except for suppression or cancer therapy.

3. 17% had TSH change of 1.0-1.5. Again major impact of cancer and suppression. But could also impact hypothyroid therapy.

4. 5% had TSH changes of 1.5-2.0 Major impact on cancer, goiter suppression, and some on hypothyroidism.

5. However, the big news was that 25% had TSH changes of >2.0. This has a major impact on all types of thyroid hormone therapy.

Do not let them switch you, and if they do, demand another blood test within 6 weeks from your physician.It is mandated to re-test if switched by 6 weeks.
Switching T4 products may result in harm to the patient without retesting.

Patients must be pro-active to secure safe, effective thyroid hormone therapy.

DR.G.

Recommendations for FNA of Non-Palpable Thyroid Nodules and Neck Lymph Nodes

At the first meeting of the Academy of Clinical Thyroidologists, the group produced a position paper on non-palpable thyroid nodules, and neck lymph nodes.

Here are the indications for Ultrasound guided FNA of thyroid
micronodules( 0.5-1cm):

1.History of radiation to head and neck during childhood.
2.Family history of medullary, or papillary thyroid cancer.
3.Micronodule in remaining lobe after hemithyroidectomy for thyroid cancer.
4.Hypoechoic micronodule with one of the following ultrasound findings.

A.Blurred margins
B.Intranodular vascularity
C.Taller that wide
D.Microcalcifications
E.Significant neck lymphadenopathy

Our indications for FNA of neck lymph nodes found in thyroid cancer patients

Any node >5 mm in height without a hilar line, and having one or more of the following characteristics:

A.Anterior-posterior/transverse ratio >0.5, in the transverse view.
B.Calcifications
C.Cystic Necrosis
D.Peripheral vascularity
E.Causes deviation of the internal jugular vien

We recommend all thyroid nodules >2 cm be biopsied, unless it is known to be "hot" on I/123 Iodine scanning.

Nodules 1.1-1.9 cm were felt to need biopsy, but the judgement of the endocrinoiologist was paramount in this decision. Some features such as comet tail, and hyperechogenicity were felt to be reasons to delay FNA, as long as there would be follow up obervation.

The full text of the position paper can be found found on www.thyroidologists.com
.
This includes references.
The work of H.Jack Baskin M.D., expert in thyroid ultrasound, was the driving force behind these recommendations.

Thank you,

Richard Guttler
The Thyroid Blog
The Thyroid Home Page