Synonyms |
|
TFT's
|
Clinical
Indications |
|
Screening
for suspected thyroid disease and monitoring treatment for
hypo- and hyperthyroidism. Guidelines
on thyroid function testing are available. |
|
Test
Includes |
|
TSH
is measured as a first line test followed up with free
T4, free T3 and thyroid
antibodies as indicated - see
laboratory TFT strategy. It should be noted that this 'TSH
first' strategy can give a false indication of thyroid status
in pituitary dysfunction. Therefore, requests for thyroid
function where pituitary dysfunction is known or suspected, must
be clearly indicated so that appropriate tests can be
undertaken.
|
|
Request
Form |
|
Combined Pathology Blood form
(Yellow/Black or Blue for GP's).
In order to help with provision of clinical details and
selection of appropriate tests, request forms include several
tick boxes for thyroid function:
-
TFT1
- Thyroid Disease?
-
TFT2
- On Thyroxine
-
TFT3
- Anti-Thyroid Rx
|
Availability |
|
On request.
|
Specific
Criteria |
|
None.
It is normally not necessary to repeat TFT's within 4 weeks.
|
Turnaround
Time |
|
Same Day (Monday to Friday)
|
Specimen |
|
Serum
|
Volume |
|
0.5 ml
|
Container |
|
Yellow top (SST) tube
|
Causes
for Rejection |
|
Unlabelled sample
|
Reference
Range |
|
Adults
(without non-thyroidal illness):
TSH 0.4 to 5.0 mU/L; free T4 12.0 to 23.0 pmol/L; free T3 4.0
to 7.8 pmol/L. |
|
|
|