Complementary Exams - Requesting them is easy, but interpreting them correctly...

Complementary Exams - Requesting them is easy, but interpreting them correctly...

When a test is ordered, laboratories usually send “normality” references with the results, i.e. the “normal” or even “acceptable” values for each test, in order to “help” those who are going to interpret the test. However, this can actually end up getting in the way of those who are less attentive, out of date or simply unprepared. Let's take a look at some of the reasons why:

• The values presented sometimes have “acceptable” ranges that are too large, with maximum values even more than 1000% from the minimum values!
• The “normal” references often vary according to each patient's clinical condition - so the right value for one patient may definitely not be the same for another.
• The result of one test often changes the parameters for others, again according to each particular case.
• Diet, sleep, fasting, the use of medication/supplements, physical exercise, the day/night before the test and many other factors alter the results and reliability/parameters.
• Many laboratories still have outdated reference values - for example, the acceptable value for TSH (the hormone released by the pituitary gland to stimulate the thyroid) has for years been less than 3 micrograms/ml, but it is still constantly written as “normal” up to 5!

Let's now look at some examples of how “plastered”, too broad, outdated or even mistaken parameters (as written in some laboratories' reports) can lead to confusion and thus harm the patient:

DHEA (an important hormone that has hundreds of actions of its own and is a direct or indirect precursor of other important hormones such as testosterone and estradiol.

To assess this, it is best to measure its most stable form, SDHEA (dehydroepiandrosterone sulphate), whose normal value for women is between 34 and 430. Is it really the case, then, that both someone with a dosage of 35 and someone with 429 are so “normal”? Of course not and, in particular and in general, I don't consider values below 200 to be acceptable at all.

🟢 Ferritin (iron “storage” protein; if low, it can mean mainly iron deficiency, but also low amounts of protein in the body or even liver problems)

For men, the reference value is between 22 and 322. Isn't this too wide a range of “normality”?

🟢 Folic acid (a vitamin that is fundamental to life and has many functions, such as acting in protein synthesis, cell multiplication, tissue reconstruction and even the prevention of anemia)

For both sexes, the “normal” value is between 3 and 17 ng/ml. The curious thing is that most of the patients I see, when they report feeling well, have values above the maximum presented here.

That's why I repeat the advice I've given before: choose the professionals who will look after your health well, because being registered with a professional council doesn't necessarily indicate proficiency or experience in their field. Tips to help you make this choice can be found in the previously published article: https://icaro.med.br/alguns-conselhos-para-quando-voce-resolver-cuidar-da-sua-saude/