The collar test is a quick examination that should be performed in all cases of suspected dengue, as it allows to identify the fragility of the blood vessels, common in infection with the dengue virus.
This test can also be called a tourniquet test, Rumpel-Leede test, or simply hair fragility test, and is part of the World Health Organization’s recommendations for dengue diagnosis, although this test is not always positive in people with dengue. Therefore, after the positive result, a blood test should be performed to confirm the presence of the virus.
- As the risk of bleeding.
- The rope test should not be used when there are already signs of bleeding.
- Such as bleeding from the gums and nose or the presence of blood in the urine.
- In addition.
- The loop test may show false results in situations such as aspirin.
- Corticosteroid.
- Pre- or postmenopausal phase.
- Or in case of sunburn.
- For example.
The loop test is primarily known to aid in the diagnosis of dengue, however, as a test for the fragility of the vessels, it can also be used when suspected of other diseases that can cause bleeding, such as:
Since the binding test can be positive in several situations, after experiencing the result, further diagnostic tests are always recommended, starting with blood tests, for example.
To do the loop test, you must draw a square on the forearm of a 2.5 x 2.5 cm surface, and then follow these steps:
Finally, the amount of reddish spots, called petechiae, in the square of the skin should be evaluated to know the test results.
Understand what petechiae are and see other causes that may be causing them.
The result of the lasso test is considered positive when more than 20 red dots appear on the square marked on the skin. However, a score of 5 to 19 points may already indicate a suspected dengue, and more tests should be done to help confirm whether the infection exists or not.
It is important to remember that the test can give a false negative even in people with the disease, so if suspected through symptoms, your doctor should order further evaluations to confirm it. In addition, it can be positive in other diseases that cause hair fragility and bleeding, such as other infections, immune diseases, genetic diseases, or the use of medications such as aspirin, corticosteroids, and blood thinners, for example.
Therefore, it can be observed that this test is not specific and should be done only to assist in the diagnosis of dengue. Learn more about the tests available to diagnose dengue.