Answers to Thyroid Function Test Case Analysis

ANSWERS - CASE ANALYSIS 1

Given results of patient:

•                    Patient                                  Reference

•      T4, Total (S) 7.0 ug/dl                         5 - 11.5

•      T3 resin uptake (S) 19%                     25 - 35

•      T3, Total (S) 134 ng/dl                       100 - 215

•      Free thyroxine index (FTI) 4.3            6 - 11.5

•      TSH (S) 22.0 uU/ml                            0.7 - 7.0

•      Antithyroglobulin Ab. Pos. (1:640)    Neg. Antimicrosomal Ab. Pos. (1:5120)     Neg. Cholesterol (S) 230 mg/dl                   140 - 225

•      (S = analyzed in serum specimens)

ANSWERS TO QUESTIONS:

1.      What does the low T3Uptake mean?

There are many TBG with active present in the sample.

2.      How would you interpret the results?

The patient may be a pregnant woman suffering from hypothyroidism. The RT3U is low indicating increased TBG, which could be seen in pregnancy. The increased TSH could indicate hypothyroidism, because TSH acts as a confirmatory test for thyroid function.