SNAP® T4 Test—Get fast results with either serum or plasma
| In the morning, take out one SNAP T4 device and replace it when you use it.* | 0 minutes |
| Use plasma from the same sample you draw for chemistries. | 2 minutes |
| Incubate the sample and prepare your SNAP T4 Test. | 6 minutes |
| Run the SNAP T4 Test (average run time). | 7 minutes |
| TOTAL TIME TO RUN SNAP T4 Test | 15 MINUTES |
*
SNAP T4 devices require 10 minutes to warm up if not removed from the refrigerator in advance. Devices can be removed from refrigeration up to 5 eight-hour cycles.
The SNAP T4 Test lets you:
- Screen for hypo- and hyperthyroidism and begin treatment or follow-up testing in the same visit.
- 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
- Perform preanaesthetic testing—Hyperthyroid cats can have secondary cardiac disease and hypertension that would indicate changes in preanaesthetic protocol.
- Monitor medications—Use as part of your protocol to help evaluate the effectiveness of treatment and adjust medications, if necessary.
The SNAP 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.
A reliable, accurate in-house testing option for immediate T4 results
The measurement of total thyroxine (T4) concentrations is a widely accepted screening tool for the analysis of thyroid function in veterinary medicine. The SNAP® T4 Test allows you to measure T4 concentrations in-house, providing the convenience of timely results and the ability to modify medications or diagnostic options during the patient appointment.
Correlation of IDEXX SNAP T4 with radioimmunoassay1
Each SNAP T4 lot is tested with canine and feline serum from both healthy animals and those with thyroid disease. The IDEXX internal calibration process ensures that each lot of T4 maintains a high level of performance and will provide accurate results for patient samples across all areas of the range.
The data presented shows excellent clinical agreement between serum T4 concentrations measured by the SNAP T4 Test and radioimmunoassay (RIA). The correlation coefficient (r) is a measure of how well a linear equation depicts the relationship between two variables. An r value of 0.92 indicates excellent overall agreement between T4 concentrations measured by SNAP and T4 concentrations measured by RIA.
1. Data on file at IDEXX Laboratories, Inc. Westbrook, ME USA
Frequently asked questions about the SNAP T4 Test
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/diarrhea/bulky stools. Polycythemia, increased liver enzymes (ALT/ALKP) and hypokalemia 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.
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 regrowth following clipping, dry or lusterless hair coat, excessive scaling, hyperpigmentation, recurrent skin infections. Common laboratory findings include a mild nonregenerative anemia and hypercholesterolemia.
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).
