SNAP® Total T4 Test

Screen for hypo- and hyperthyroidism during patient visits

The new SNAP® Total T₄ Test provides convenient, clinically accurate results in-house in just 15 minutes for diagnosing and monitoring thyroid disease.

The SNAP Total T4 Test results correlate extremely well with IDEXX Reference Laboratories methodology, eliminating confusion in result interpretation from one methodology to another.
The test simplifies your work flow with one single dynamic range and one sample volume for canine, feline and equine patients.
It’s fully quantitative, so you can monitor the course of thyroid disease, evaluate therapeutic responses and better assess disease progression during patient visits.

Read the Thyroid Roundtable (PDF) for more information about Total T4 and thyroid conditions in cats and dogs.

The SNAP® Total T4 Test is for use only with the SNAPshot Dx® Analyser.

Benefits
Accuracy
How To/Resources
FAQs

SNAP® Total T₄ Test—Accurate Results in-house in 15 minutes

In the morning, take out one SNAP Total T₄ device and replace it when you use it.*	0 minutes
Use plasma from the same sample you draw for chemistries	2 minutes
Incubate sample and prepare your SNAP Total T₄ Test	6 minutes
Run the SNAP Total T₄ Test (average run time).	7 minutes
TOTAL TIME TO RUN SNAP Total T₄ Test	15 MINUTES

*

SNAP Total T₄ devices require 15 minutes to warm up if not removed from the refrigerator in advance.

The SNAP Total T₄ Test lets you:

Screen, monitor and diagnose thyroid disease with one easy work flow and begin treatment or follow-up testing in the same visit.
See immediate results. Diagnose, adjust therapy and dispense medication during the patient visit for improved real-time patient care and increased client compliance and satisfaction.
Include a total T4 test as part of your routine wellness screen along with a CBC and chemistry profile.
Perform reflex testing immediately: 66–75% of hypothyroid dogs have elevated cholesterol, and more than 90% of hyperthyroid cats show increases in ALT or ALKP.1

The SNAP Total T₄ Test uses proven SNAP® ELISA technology to ensure the accuracy you need for confident diagnoses.

1.

Feldman EC, Nelson RW. Canine and Feline Endocrinology and Reproduction. 3rd ed. Philadelphia, PA: WB Saunders; 2004.

The new SNAP® Total T4 Test is a clinically accurate in-house testing option

We’ve thoroughly evaluated, studied and refined the new SNAP® Total T4 Test, so you can depend on your results.

To ensure optimal accuracy, reliability and ease of use, we invested more than five years in research and development.
The test was evaluated by 22 North American veterinary practices.
More than 1,300 patient samples have been tested on the SNAPshot Dx® Analyser.

The reference intervals and interpretive information for the new SNAP® Total T4 Test are directly aligned, and correlate extremely well, with the IDEXX Reference Laboratories Total T4 test. A collaborative approach in the research and development of the SNAP Total T4 Test has eliminated confusion in result interpretation from one methodology to the other.

Run the new SNAP Total T4 Test on the SNAPshot Dx Analyser to get the benefit of proven ELISA technology.

State-of-the-art digital imaging system and proprietary image analysis algorithms produce reliable, accurate test results in your clinic.
Accurately quantifies total T4 in either serum or plasma samples from dogs, cats and horses.
A reliable and convenient option for screening and monitoring patients with thyroid disease using your in-house laboratory.

Read the IDEXX SNAPshot Dx® Analyser SNAP® Total T4 Performance Study (PDF).

Resources and support materials for the SNAP® Total T4 Test

1.

Following the on-screen instructions on the SNAPshot Dx® Analyser, dispense 65 µL of sample into a disposable tube. Make sure you use the purple pipette.

2.

Dispense 300 µL of conjugate into the same sample tube used in step 1.

3.

Gently invert the sample tube 4–5 times to mix.

4. Incubate the sample tube for 5 minutes.	5. Pour entire contents of sample tube into the sample well of the SNAP* device.	6. When colour first appears in the activation circle, press the activator.
7. Immediately load the SNAP device into an available port on the analyser.

Note: So you’ll always be prepared, take a SNAP® Total T4 Test and conjugate out of the refrigerator in the morning to bring them to room temperature; replace the test as you use it.

View the package insert for detailed instructions.

Interpreting Results

Species	Reference Intervals
	U.S. Units (µg/dL)		SI Units (nmol/L)
Canine	<1.0	Low	<13	Low
	1.0–2.0	Low Normal	<13–26	Low Normal
	1.0–4.0	Normal	13–51	Normal
	>4.0	High	>51	High
	2.1–5.4	Therapeutic	27–69	Therapeutic

Feline	<0.8	Subnormal	<10	Subnormal
	0.8–4.7	Normal	10–60	Normal
	2.3–4.7	Gray zone in old or symptomatic cats	30–60	Gray zone in old or symptomatic cats
	>4.7	Consistent with hyperthyroidism	>60	Consistent with hyperthyroidism

Equine	<1.0	Low	<13	Low
	1.0–3.8	Normal	13–49	Normal
	>3.8	High	>49	High

Note: 1 µg/dL is equal to 12.87 nmol/L.

Resource List

Diagnosing and Managing Thyroid Disease in Dogs and Cats

Sample Preparation Poster

Frequently asked questions about the SNAP Total T₄ Test

What does the SNAP T₄/Total T₄ Test measure?

The SNAP T₄/Total T₄ Test measures total thyroxine, commonly referred to as “total T₄” or “T₄.”

What is hyperthyroidism?

Hyperthyroidism is a syndrome resulting from excessive production of thyroid hormones, resulting in an increased basal metabolism. Hyperthyroidism is the most common endocrinopathy in cats, but is very rare in dogs. Common clinical signs include weight loss, polyphagia, increased activity/restlessness/nervousness, hair loss/unkempt coat, polyuria/polydipsia, vomiting/diarrhoea/bulky stools. Polycythaemia, increased liver enzymes (ALT/ALKP) and hypokalaemia are common laboratory findings.

At what age should cats be tested for hyperthyroidism?

Hyperthyroidism occurs in middle- to old-aged cats with a mean age of 11–13 years. It is rare in younger cats, but any cat over 4 years of age with compatible clinical signs should be screened. All cats over 7 years of age should be routinely screened for hyperthyroidism.

After diagnosis of hyperthyroidism, what is the next step?

There are three primary treatment options available for hyperthyroid cats:

Medical therapy
Surgical removal of the thyroid gland
Radioactive iodine treatment

Can I use SNAP T₄/Total T₄ Test to monitor response to treatment?

Yes, the SNAP T₄/Total T₄ Test is fully quantitative and enables you to monitor response to treatment. With the ability to monitor T₄ levels in-house, you can make immediate adjustments to thyroid medication and discuss the course of illness and treatment while the client and patient are present.

What is hypothyroidism?

Hypothyroidism is a syndrome resulting from inadequate production and secretion of thyroid hormone by the thyroid gland. Hypothyroidism is the most common endocrinopathy in dogs but very rare in cats. Common clinical signs include lethargy, inactivity, weight gain, cold intolerance, hair loss or excessive shedding, lack of hair re-growth following clipping, dry or lusterless hair coat, excessive scaling, hyperpigmentation, recurrent skin infections. Common laboratory findings include a mild nonregenerative anaemia and hypercholesterolaemia.

At what age should dogs be tested for hypothyroidism?

The onset of clinical signs can occur at varying ages but generally appear during middle age (4–10 years). Some high-risk and large- or giant-breed dogs can develop signs at an earlier age (2–3 years). All dogs with compatible clinical signs should be screened for hypothyroidism.

After diagnosis of hypothyroidism, what is the next step?

The treatment of hypothyroidism involves thyroid supplement therapy. The goal is to treat the dog with the lowest possible dose that alleviates clinical signs and keeps the thyroid concentration in the upper end or slightly above the reference interval at peak levels (approximately 4–6 hours post-pill).

Can I use the SNAP T₄/Total T₄ Test to monitor response to levothyroxine therapy?

Yes, the SNAP T₄/Total T₄ Test is fully quantitative and enables you to monitor response to treatment. With the ability to monitor T₄ levels in-house, you can make immediate adjustments to thyroid medication and discuss the course of illness and treatment while the client and patient are present.

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