This week, a thyroid patient from British Columbia posted an image of a piece of paper handed to her at a LifeLabs laboratory.
LifeLabs BC was using this paper leaflet to explain to her why “Free T3 and Free T4 will not be tested when the TSH is in reference range.”
THE LEAFLET GIVEN TO THE PATIENT
The paper says this:
“Thyroid Protocol Changes.
- The Thyroid Protocol is being simplified
- Going from 80 diagnoses and conditions that qualified for special case to 6
- The new special list is:
YES: Diagnosis or comments on the requisition include any of the following words or phrases:
- Secondary Hypothyroidism (MUST specify “secondary”)
- Tertiary Hypothyroidism (MUST specify “tertiary”)
- Suspected / Query (?) analytical interference (Requisition MUST indicate that the ordering practitioner has obtained approval by a laboratory physician prior to ordering)
All other diagnoses and comments do not qualify as special case.”
In this post, I’m going to focus on analyzing the leaflet itself in light of its context in our health care system.
Overall, the handout itself illustrates the failure of the TSH-centric thyroid testing policy both locally at LifeLabs BC and in general.
First of all, it shows unintelligent and inefficient procedures at LifeLabs and their inept communication strategies.
Secondly, the handout reveals a failure in quality control.
Thirdly, the handout reveals that the blinding TSH paradigm is the major problem with thyroid testing today. Inconsistent results should be expected more often.
Because of all these failures, this testing policy can’t even diagnose the many ways in which thyroid therapy and human biochemistry can compromise the pituitary gland and hypothalamus gland — it’s essentially blind to diagnose the valid special cases it lists!
At the end, I’ll reveal an easy fix for this failed policy.
THE CONTEXT OF THIS HANDOUT
This is just a local event in a huge machine of policy that is changing how thyroid laboratory testing occurs across Canada and in many countries today.
The Canadian Society for Endocrinology and Metabolism has put naive faith in thyroid guidelines by the American Thyroid Association, one of whose purposes appears to be to defend the narrow monopoly of TSH monotesting and T4 monotherapy from all reasonable scientific and clinical doubt as well as patients’ complaints of ineffective therapy. They have offered our vulnerable thyroid hormone levels as a sacrifice to ATA dogma and penny-pinching pressures. They use campaigns like “Choosing Wisely,” richly funded by provincial governments, to advance policies to cancel the lab tests that we need to optimize our thyroid hormones to our individual setpoint. These policies are then implemented by provincial health care systems, pushed onto laboratories and doctors and reinforced in medical schools.
Today, according to the way Canadian endocrinology testing toolkits and guidelines are being worded, the only justification for testing Free T4 and Free T3 during routine hypothyroid therapy when the pituitary TSH is normal will be based on central hypothyroidism (which causes TSH hyposecretion or bioinactive TSH).
Of course, this policy denies all equally valid health reasons for measuring thyroid hormone levels.
It prevents the diagnosis of real biochemical hypothyroidism and tissue hypothyroidism that can be hidden under a normalized TSH.
5 SPECIAL CASES ARE REALLY ONLY ONE
Naive people at Life Labs seem to be saying to the thyroid patient, “Wow look at all those 6 special cases or diagnoses you could have that would still justify a FT3 and FT4 test!”
Anyone who understands secondary hypothyroidism will note that items 1-5 are synonyms for of ONE general diagnosis of “Central Hypothyroidism.”
Central hypothyroidism, a condition of TSH hyposecretion, is caused by
1) Pituitary failure, which causes
2) Secondary hypothyroidism, and/or by
3) Hypothalamic or
4) Hypothalamus failure, which causes
5) Tertiary hypothyroidism.
This is not a DIAGNOSIS list. It’s a VOCABULARY list.
Now we know how brainless an operation this is at Life Labs.
This list is for people who know absolutely nothing about thyroid hormones. This list is for uneducated lab workers who don’t even know common suffixes in English.
Unbelievable! They need to be told that “hypothalamic” is an adjective for the noun “hypothalamus.”
They are being told to look for words like “secondary hypothyroidism” and “pituitary failure,” but they obviously have no idea that those words mean exactly the same thing.
They aren’t even aware that “central hypothyroidism” is missing from their vocabulary list.
Medically uninformed staff members are checking OUR requisition forms with an eye to cancelling test orders whenever they don’t have “magic words” on them that Life Labs has put on a vocabulary list!
DID YOU REALLY USE A LIST OF 80 SYNONYMS?
Life Labs BC, you look very foolish now that we see that vocabulary lists are part of your inefficient and uneducated procedures.
The leaflet says this: “Going from 80 diagnoses and conditions that qualified for special case to 6.”
Do you expect that your gullible reader of the leaflet, the thyroid patient, should be impressed by the number “80”?
Do you think we really believe that there used to be 80 unique diagnoses and health conditions that are mutually exclusive and that they all require a Free T4 and/or Free T3 test?
LifeLabs, you are admitting to thyroid patients that you used to have a list of 80 SYNONYMS that somebody in your staff naively believed were actually discrete “diagnoses and conditions.”
And you were making uneducated laboratory workers scan a list of 80 items whenever they got a requisition for FT3 and FT4!
How inefficient is that?
It makes it seem like patients and their doctors are being denied vital tests just so that the laboratory worker doesn’t have to scan such a long list of synonyms.
ANALYTICAL INTERFERENCE IS A DIFFERENT ISSUE
The 6th special case in which Free T3 and Free T4 testing may be permitted is “analytical interference.”
This item also gives us insight into a flawed laboratory quality control system.
This final “special case” permits the “laboratory physician” to have veto power over the test ordering physician when laboratory test technologies and procedures are in question.
Question: When are you as a doctor permitted to question the validity of a TSH, FT3 or FT4 test result?
Answer: Almost never, or with great difficulty!
This technical aspect of lab tests is limited to cases such as
- the handling of blood samples, such as storage and temperature and attributing the sample to the correct patient,
- the storage and maintenance of materials and equipment like chemical reagents and assay machines
- the manufacturer’s or local laboratory’s process used to establish a statistical population reference range, such as not excluding thyroid patients or unhealthy people when establishing FT3 or FT4 reference ranges.
- the failure of the technology to analyze the concentration properly, and
- the manufacturer’s test’s failure to detect different types of TSH molecules or antibodies to TSH
Requiring the test-ordering physician to have the prior approval of the laboratory physician is like asking a head chef to go through his kitchen looking for contaminants just because one customer got sick. Not going to happen.
You need an unbiased medical inspector to enforce and carry out the checking.
Getting the lab to approve the questioning of their own lab test is ridiculous. It is a procedure meant to shield the laboratory’s processes and procedures, and ultimately shield the laboratory assay and platform’s manufacturer. It protects these these industry players from being questioned.
Assay interference does not justify either a TSH, FT3 or FT4 re-test only from the same laboratory.
Any genuine suspicion of analytical interference would justify going to at least one different laboratory, if not two, to use their test based on different assay manufacturers. Ideally you would test a single blood sample on several brands of assays (Roche, Abbott, and on) to see the degree to which the test results are discordant with each other.
Even more ideally you’d get it tested by a gold-standard “liquid chromatography tandem mass spectrometry” TSH, FT4 or FT3 test.
Discovering the reasons for FT3 or FT4 results inconsistent with TSH or clinical presentation is essential to the diagnosis of all thyroid patients.
We are worthy of the best laboratory service because our lifelong therapy depends on exact thyroid hormone dosing.
These are critical lab tests.
Certain manufacturers’ FT3 and FT4 tests have problems, and LifeLabs currently uses the untrustworthy Abbott assay and suspicious methods of determining the FT3 reference range.
- Abbott Laboratories’ reference range normalizes lower Free T3
- The Abbott Free T3 test kit recall of 2018-2019
Test quality concerns should be carefully investigated and fixed rather than making them too difficult to question.
WHAT LIES BENEATH “ANALYTICAL INTERFERENCE”?
This final item on the LifeLabs BC handout indirectly reveals the deeper failure of our current thyroid testing policy.
Why is this final item of “analytical interference” even mentioned as a “special case” for FT3 or FT4 testing?
This item in the list is not like the others.
It is not a medical diagnosis or health condition. It is something that could be a problem with ANY lab test.
Now let’s think critically about why this irrelevant item appears in this list.
Perhaps doctors have received TSH test results that are inconsistent with clinical presentation and/or a previous FT3 and FT4 test result. Puzzling over the inconsistency, the doctors have suspected analytical interference. They seem to have tried to use this reason to justify their request for FT3 and FT4 testing (or re-testing).
Policies like these are born from administrative annoyance, not the protection of health.
This problem is actually caused by “TSH-paradigm interference.”
The standard paradigm presumes TSH should be consistent with FT3 and FT4 and perhaps even a patient’s clinical status. This paradigm will “interfere” with thyroid test interpretation.
Extreme trust in TSH secretion makes many doctors suspect the FT3 and/or FT4 test is untrustworthy, or the TSH assay, when these assays are reliable enough to be used in research when they are properly validated and verified.
This policy sweeps puzzling results under the rug.
Trust in TSH and the laboratory is maintained by never seeing conflicting FT3 and FT4 results during therapy.
DIAGNOSE THE POLICY FAILURE
We need to observe TSH inconsistency with FT3 and FT4 and clinical presentation.
Collecting the inconsistent data is necessary to correctly diagnose not only the laboratory test quality and the patient’s thyroid hormone status. But first we have to diagnose this deeper issue …
The critical FAILURE of this TSH-centric thyroid testing policy in the context of thyroid therapy.
- You can’t observe the failure of TSH-only testing by repeatedly testing only the TSH!
Consider all the ways in which normalized TSH fails to give enough information to guide effective thyroid therapy:
- Individual thyroid ranges are 38-68% the size of the lab reference range
- Targeting TSH? It’s not as specific or as sensitive as people claim.
- Several fallacies in the TSH-T4 paradigm of thyroid therapy
- TSH “can be very misleading” during thyroid therapy, say researchers
- How TSH ultrashort feedback works, and antibody interference
A QUICK FIX FOR THE POLICY FAILURE
Make thyroid batch testing the norm and the requirement within thyroid therapy.
Batch thyroid testing is cheap.
Batch testing saves on staff time, assay reagents, and blood draws and paperwork. It is 1/2 to 1/3 the price of testing TSH, FT3, and FT4 separately through three different blood samples or separate blood draws.
Don’t trust the laboratory to estimate the true cost — they will always inflate the cost as if the tests were _not_ done through batch testing.
The lifelong health and welfare of thyroid patients is worth a few dollars extra per test.
Add a checklist item to the laboratory requisition:
“X = Full thyroid testing including FT3 and FT4 (Note: This is to be used only in patients dosed with thyroid hormone and patients with severe or chronic thyroid symptoms despite a normalized TSH.)”
This should cover all the necessary, valid conditions for FT3 and FT4 testing.
- Now there’s no need for any silly vocabulary lists for exceptions to rules.
- Now you can give due respect to the doctor’s expert clinical judgment.
- Now you can prevent unnecessary conflict between doctors and laboratories.
- Now you can calmly learn from seeing normal TSH results that do not reveal the human suffering caused by low (or very low-in-range) FT3 and FT4 and significantly lower FT3:FT4 ratios during thyroid therapy.
- Now you don’t have to discipline doctors or send them for brainwashing sessions to be re-indoctrinated in the TSH-paradigm whenever they continue to order FT3 and FT4 tests.
Instead, you can spend health care resources on something more fruitful that will help thyroid patients.
You could mount workshops that teach doctors how to use TSH, FT3, and FT4 levels within reference range to optimize thyroid patients’ therapy to the individual.
– Tania S. Smith