Triiodothyronine (T3) Resin Uptake (RUR)
(T3 Uptake)

Sample type:-

Serum

Uses:-

1. The T3 resin uptake is used by doctors to estimate the amount of TBG in the blood, and how much T4 and T3 in the blood is free form and available to affect the body.

2. RUR is inversely proportional to unsaturated hormone-binding sites.

3. Total T4 × RUR is proportional to free T4 and inversely proportional to TSH.

Precautions :-

• No special preparations are needed for a T3RU. However, certain medications, including seizure medications, steroids, and birth control pills, can affect the results.

Interfering factors:-

• If there’s either too much or too little TBG in the blood, the measurements of total T3 and T4 levels will be affected, which can make it difficult for doctors to tell whether a person actually has a thyroid problem without also knowing the results of the T3 resin uptake.

• Pregnancy and Some drugs that can decrease T3RU levels.

• In some cases of severe nonthyroid illness, RUR does not fully compensate and does not adjust the T4 into the normal range.

• Normal in pregnancy with hyperthyroidism, nontoxic goiter, and in use of certain drugs (e.g., mercurials, iodine).

Pre -analytical errors:-

• Unlabeled or mislabeled specimen.

The Corrective action

• Reject the sample and another one is requested.

Post analytical errors:-

1. Write wrong name on the report.

2. Send wrong results to the patient.

The Corrective action:-

1. make sure that the name and all data are right

2. Communicate to the patient and apologize for this mistake and sent the right report to him.

Reference rang:

24% to 37%.

Normal value ranges may vary slightly among different laboratories.