How Thyroid Testing Has Developed
MAY 17, 2017
Jane McDaniel, MS, MLS (SCP) SC, Wake Forest School of Medicine explained that typically, the most common forms that are talked about are the thyroid panel, but most physicians will end up ordering a thyroid-stimulating hormone (TSH) to start with.
“TSHs have evolved over the years to the point that it’s now considered the best test to use. It’s also the 3rd generation of the TSHs, which are the mot sensitive; so almost all the testing that’s done is with the 3rd generation TSHs,” McDaniel said.
However, if those turn out to be abnormal (can cover the whole range from hypo to hyperthyroidism), then the physician will order a thyroid panel, which will give them the T3 and T4 freethyroxine index that would help them understand a little more about what’s going on with the patient.
According to McDaniel, several symptoms are involved with hyperthyroidism and hypothyroidism that are evidenced from thyroid testing. For instance, if a patient has hyperthyroidism, they’re typically going to have low cholesterol, sweating, and many physical and chemical signs and symptoms in the body.
She did discuss that if no thyroid disorder is found, the clinician will still assess the patient, specifically to look for other causes of the symptoms the patients have. The 3rd generation TSH assays will actually pick up very small differences in the thyroid-stimulating hormone and are helpful in adjusting thyroid medication dosage.
One of the key points of McDaniel’s talk was about a case study regarding a patient who presented with what appeared to be hypothyroidism – she had an elevated TSH and symptoms of hypothyroidism, but was also on birth control pills. McDaniel’s team did all the studies on that and found out she, in fact (because some of the T3 and T4 tests are in the normal range), is hypothyroid and was started on levothyroxine. They then monitored her TSH levels, which helped them discover that the TSH levels decreased over time.
Since they did measure about 6-weeks out, the patient returned feeling jittery. The team found the levothyroxine had taken her levels so low that she’s starting to feel “jittery. As a result, the team adjusted her medication based on the 3rd generation assay, which, McDaniel said, was valuable to making sure the patient was on the right dosage.