Thyroid Stimulating Hormone (TSH)

Thyroid disorders affect more people worldwide than diabetes. In the USA, 27 million people have thyroid disease and more than 50% go undiagnosed.

The majority of thyroid disorders fall into the category of hypothyroidism (underactive thyroid) which is assessed by determining the levels of thyroid stimulating hormone (TSH) in the blood.

The diagnostic test for TSH is the largest volume immunoassay run in central laboratories today, with around 200 million assays run each year globally.

It is considered to be the industry gold standard for immunoassays by which major diagnostic companies measure the performance of competing platforms. To be of clinical utility, TSH tests must be extremely sensitive and be able to measure the concentration of the target hormone in blood over a very wide range (3 to 4 orders of magnitude). The requirement for sensitivity in the picomolar range has previously been a barrier to bringing the test to the point of care while ensuring sufficient dynamic range is available in a point-of-care system can also be challenging.

Vivacta’s TSH diagnostic test meets these requirements and in so doing demonstrates the high sensitivity, wide dynamic range, precision and speed to result enabled by the technology platform. Vivacta’s TSH test performs as well as laboratory-based tests but produces results in a fraction of the time.

Patients are tested for TSH if their physician suspects them of hypothyroidism, which leads to higher-than-normal levels of TSH. A high TSH reading, even within the reference range, may be associated with coronary heart disease and less favourable lipid (eg cholesterol) concentrations in the blood. For diabetics, hypothyroidism may interfere with glycemic control. In pregnant women, untreated hypothyroidism during pregnancy increases the risk of gestational hypertension and complications at delivery with many commentators calling for more extensive TSH screening of expectant mothers.

Hypothyroidism is treated with thyroxine, which must be accurately dosed to ensure benefit and avoid the side-effects of too high a dose. Patients taking thyroxine must be monitored at regular intervals. Owing to possible interferences with glycemic control, it may be appropriate to monitor diabetic patients more frequently.

Vivacta’s TSH test has potential as a companion diagnostic by providing information to physicians whether to initiate a patient on thyroxine treatment. In addition, once thyroxine treatment has begun, Vivacta’s test may be suitable for monitoring the patient’s TSH levels to ensure the correct dose is attained and maintained.

Benefits for TSH diagnosis:

• Improved clinical efficiency: use TSH readout for earlier clinical decision-making
  
• Facilitates immediate patient/physician face-to-face discussion of options
• Subclinical thyroid abnormality results are hard to discuss fully over the phone or by email
• Thyroxine drug titration is a slow and multistep process; Point-of-Care testing simplifies and speeds achievement of targeted dose