According to a research team from the University of South Florida Health (USF Health) Morsani College of Medicine, a screening blood test that was originally validated in seriously ill patients without COVID-19 is still clinically useful for ruling out pulmonary embolism in patients hospitalized with the coronavirus.
Diagnostic research in JAMA Network Open on Oct. 8 to see how well D-dimer testing worked in excluding pulmonary embolism in COVID-19 patients hospitalized.
The D- Dimer Test Is Still Useful In Ruling Out Pulmonary Embolisms
Doctors who suspect pulmonary embolisms use the widely accessible D-dimer test to rule out the potentially fatal blood clotting disease, which occurs most frequently in surgical patients who are immobilized for lengthy periods and patients admitted to the intensive care unit.
During the tough phase of viral infection, the experts were much dependent on the level of D-Dimer that can help them know the status of the virus in the body.
However, in recent research, it was stated that this system is not as effective as expected. Yet, as per a team of specialists, the level of D-dimer can help them in ruling out the probabilities of one’s health state where he needs to be admitted in a hospital.
D-dimer is a simple blood test that measures protein fragments of blood clots floating in the bloodstream. D-dimer levels, normally undetectable or detectable at very low levels, rise sharply when the body is breaking down the clots.
“Our research shows that clinicians may interpret D-dimer levels in COVID patients the same way they do in other patients; we don’t need a special (different) value for COVID patients,” said Dr. Oxner, associate professor and vice-chair of USF Health Internal Medicine. “So, if d-dimer levels are low in hospitalized COVID patients, we can correctly rule out a pulmonary embolism.”
When blood clots form in another area of the body (usually the leg), they travel through the bloodstream and lodge in the blood arteries of the lungs, reducing blood flow and producing low oxygen levels.
According to Dr. Oxner, COVID-19 patients are three to ten times more likely than other hospitalized patients to develop pulmonary embolisms, even when they are not as sick or immobilized.
The COVID-19 virus appears to create a cellular environment that favors clotting by making the inside of blood vessels uneven, irritable, and prone to microtears, according to scientists.
A negative D-dimer test (one that excludes pulmonary embolism) can help patients avoid more costly, intrusive diagnostic procedures such as computed tomography, pulmonary angiography, or CTPA. The test also necessitates an IV contrast injection, which increases the risk of kidney damage while you’re ill.
The USF Health researchers wondered if the higher risk of blood clotting in COVID-19 patients, as well as the uncertainty of various D-dimer values identified in earlier smaller studies, hampered the efficacy of the existing screening tool to appropriately rule out pulmonary embolism in COVID patients.
The common wisdom was that because D-dimer levels are virtually always elevated in COVID-19 patients, the test was originally validated (in non-COVID patients) would be ineffective in distinguishing COVID individuals without clots.
The retrospective study looked at the records of 1,541 COVID-19 patients who were admitted to Tampa General Hospital between January 1, 2020, and February 5, 2021. In 287 of those patients, they compared plasma D-dimer concentrations to CTPA, the criterion for diagnosing pulmonary embolism.
The majority (91.2%) of COVID-19 patients with CTPA evidence of pulmonary embolism had D-dimer levels of 0.05 g/mL or higher, as did all patients with CTPA evidence of pulmonary embolism. (Any D-dimer concentration above 0.05 g/mL is considered positive for pulmonary embolism, whereas anything below that level is considered negative.)
