Discussion
Coagulopathy becomes evident with increase in D-dimer and fibrinogen
levels and minimal change in prothrombin time (PT), active partial
thromboplastin time (aPTT) and platelet count 15.
Hematological laboratory results can be used to determine the severity
and prognosis of COVID-19 infection. Thrombocytopenia has been shown to
be associated with an increased risk of severe disease and mortality
associated with COVID-19 18. Platelet count has been
accepted as a potential marker for COVID-19 since it is a simple,
inexpensive and easily available hematological marker and since it is
independent of disease severity and morbidity risk in the intensive care
Unit 19.
In a study conducted on thrombocytopenia with patients with COVID-19,
mild thrombocytopenia was observed in approximately 5% of patients who
had mild disease, thrombocytopenia was observed in 70-95% of patients
who had severe disease 5-19. In a meta-analysis, when
platelet count was compared, a significant difference was found between
the COVID-19-negative group and the group that had severe COVID-19 in
terms of platelet count and the individuals who had severe disease were
found to have lower platelet count 18. In another
study conducted on 1476 patients, a direct correlation was found in
patients with COVID-19 between the decrease in platelet count and
mortality 20. In another study conducted on patients
with COVID-19, it was reported that low platelet count was associated
with increased severe disease and death risk and it could serve as an
indicator of worsening of the disease during the hospital stay in
COVID-19 18. It has been reported that platelet count
decreases significantly in patients with COVID-1921-22 and it is lower in patients who do not survive
compared with those who survive 23.
Our study was found to be in parallel with the literature, a significant
difference was found between groups and platelet count was found to be
lower in the COVID-19 (+) group (U=5435.000, p=0.002, Effect
size=0.20)(Table 2).
D-dimer is a fragment produced by the cleavage of fibrin by plasmin
during clot breakdown 24. One of the most common
laboratory findings in patients with COVID-19 who require
hospitalization is the obvious elevation in D-dimer. A high D-dimer
value has been reported as a poor prognostic marker associated with
consistent critical course and higher mortality in patients with
COVID-19 25-26. In a study conducted on 1099 patients
with COVID-19 in China, high D-dimer levels were found in almost half of
the patients 27.
In an observational study conducted on 183 patients in China, a
statistically significant difference was found in the mean D-dimer
concentration at admission between patients with COVID-19 who survived
and those who did not 8. In another study conducted,
patients with COVID-19 treated in ICU (Intensive Care Unit) were found
to have higher D-dimer levels than patients with COVID-19 who were not
treated in ICU 5. Finally, in another study involving
5279 patients with COVID-19, the COVID-19 (+) group was compared with
the COVID-19 (-) group. The D-dimer level of the COVID-19 (+) group was
found to be four times higher 28.
Our study was found to be consistent with the literature. The difference
between groups was found to be significant. D-dimer levels were found to
be higher in the COVID-19 (+) group, while they were found to be lower
in the Covıd-19 (-) group (U=1457.500, p<0.001, Effect
Size=0.69)(Table 2).
Among coagulation parameters, PT is another laboratory parameter with
varying consequences in COVID-19. PT and aPTT are exogenous and
endogenous coagulation system factors that can be used for the early
diagnosis of DIC (Disseminated Intravascular Coagulation). In another
observational study conducted on 183 patients in China, a mild
prolongation was found in the mean PT concentration at admission between
patients with COVID-19 who survived and those who did not and a
statistically significant difference was found between the groups8. In another study conducted in China, the patients
receiving treatment in ICU were found to have higher PT prolongation
compared with patients who were not receiving treatment in ICU and a
significant difference was found between the groups 5.
In another study conducted on 187 patients diagnosed with COVID-19 and
treated in the hospital, patients with high troponin-T level were found
to have prolonged PT and aPTT levels 29. More
pronounced prolongation of PT and APTT parameters indicates that
patients are in a transition from high coagulation state to fibrinolytic
state due to excessive coagulation factor consumption.
Our study was found to be consistent with the literature, a significant
difference was found between the groups in terms of PT levels and
prolongation was found to be higher in the PCR (+) Group (U=3765.500,
p<0.001, Effect Size=0.40) (Table 2).
In conclusion, the relationship between PT, aPTT, DİMER, INR, PLT levels
was evaluated according to COVID-19 results and gender. Our study showed
statistical significance between groups in PT, D-dimer, INR, PLT values
between PCR positive and negative groups in terms of especially COVID-19
results (p<0.01). It is important to find out coagulopathy and
thrombocytopenia in Covid-19 patients. These parameters are also
important biomarkers for the prognosis of the disease in COVID-19.
The results of this study have shown that hypercoagulation exists in
patients with COVID-19 at an early stage and hypercoagulation is closely
associated with disease progression and clinical outcome. For this
reason, coagulation indicators such as D-dimer and PT should be
monitored as early as possible to determine thrombotic complications. It
is imperative to take preventive treatment to decrease thromboembolism
and DIC risk secondary to coagulation disorder and thus to reduce the
morbidity and mortality of patients infected with COVID-19.
Conflict of interest statement
There is no conflict of interest between the authors.