The baseline demographics of all individuals were shown in Figure 1. When comparing the moderate and severe COVID-19 patient groups to the control group, there was a no significant in age (P>0.05). The severe group comprised 66 percent males and 34 percent females (P>0.05), while the moderate group had similar numbers of males and females.
Table 1 demonstrates the levels of serum ALT, AST, albumin, CRP, IL-1β, IL-4, IL-6, IL-18, IL-35, PGE2 and TXA2 levels as well as the expression of NF-κB p50 and NF-κB p65 mRNA in all studied groups. When compared to healthy controls, ALT, AST, albumin, and CRP levels indicated significant rises in moderate and severe COVID (P<0.001). When compared to the moderate group, patients in the severe group had significantly higher ALT (P<0.001), AST (P<0.05), and CRP (P<0.001). In addition, when compared to healthy controls, albumin levels were significantly lower in moderate and severe COVID-19 patients (P<0.001). When compared to the moderate group, albumin levels in the severe group were significantly lower (P<0.01).
In addition, IL-1β, IL-4, IL-6, IL-18, IL-35, PGE2, and TXA2 levels in moderate and severe COVID-19 patients were significantly higher (P<0.001) than in healthy controls. IL-6 was substantially greater (P<0.001) in the severe group than in the moderate group, although IL-1β and TXA2 were significantly higher in the moderate group than in the severe group. When comparing the moderate and severe groups, no significant differences in IL-18, IL-35, or PGE2 were found (p>0.05).
Furthermore, NF-κB p50 and NF-κB p65 mRNA expression levels in moderate and severe COVID patients were significantly higher (P<0.001) than in healthy controls. The moderate group, on the other hand, NF-κB p65 mRNA expression had significantly higher levels (P<0.05) than the severe group. Although it is not significant (P>0.05), the moderate group's NRP-1 mRNA expression level was higher than the severe group's.
Table 1 also shows that NRP-1 mRNA expression levels in moderate and severe COVID patient groups were significantly higher (P<0.001) than healthy controls.
Table 2 illustrates the relationship between CRP, PGE2 and TXA2 levels, and NF-κB p50, NF-κB p65 and NRP-1 mRNA expression with all other tested parameters in moderate group. CRP, PGE2 and TXA2 levels and NF-κB p50, NF-κB p65 and NRP-1 mRNA expression revealed a significant positive connection with all parameters in the moderate COVID-19 patient group, except for albumin which shows a significant negative correlation (P<0.01) with CRP and a non-significant (p>0.05) negative relationship PGE2, NF-κB p50 and NRP-1 mRNA expression.
Table 3 illustrates correlations between IL1β, IL4, IL-6, IL-18, and IL-35 with all other tested parameters in moderate group, where albumin shows non-significant (P>0.05) relationship with all cytokines except for IL-18 which has a significant negative correlation (P<0.05). IL4, IL-6, IL-18, and IL-35 shows a significant positive correlation with all parameters. IL1β showed non-significant (P>0.05) relationship with ALT, AST and albumin but it had a significant positive correlation (P<0.001) with others.
In the severe group, Table 4 illustrates the relationship between CRP, PGE2, TXA2, NF-κB p50, NF-κB p65 and NRP-1 with all other tested parameters in severe group. CRP and TXA2 serum levels and NF-κB p50, and NF-κB p65 mRNA expression revealed a significant positive connection with all other parameters in the severe COVID-19 patient group. Serum albumin level shows a significant (p<0.001) negative relationship with CRP, PGE2, TXA2, NF-κB p50, NF-κB p65 and NRP-1 mRNA expression. PGE2 showed non-significant (p>0.05) relationship with AST, while, NRP-1 mRNA expression showed non-significant (p>0.05) relationship with ALT and AST.
Table 5 depicts the correlation between serum IL1β, IL4, IL-6, IL-18, and IL-35 levels with all other tested parameters in severe group. All serum cytokine levels revealed a significant positive connection with all parameters in the severe COVID-19 patient group, except for albumin, which showed a significant negative relationship with all cytokines and NF-κB p50 expression which had non-significant (p>0.05) positive relationship with serum IL-4 level.
In order to accurately classify COVID-19 patients, we ran an area under the ROC curve (AUC) analysis on each parameter in the moderate group in Table 6. In the AUC study, a total of nine parameters produced a significant result (Table 6). Only TXA2 and NF-κB p65, however, displayed an AUC greater than 0.80. TXA2, which has an AUC of 0.843, was in fact a useful biomarker for early COVID-19 diagnosis since AUC = 0.843 of 95 % CI [0.782–0.904] and P<0.001 (Table 6 and Figure 3D). TXA2 was the only one to give an AUC over 0.80, indicating that it is a good biomarker to detect moderate COVID-19. Additionally, the TXA2 cut-off value obtained was 213.95 pg/mL, with a sensitivity of 88.0 % and specificity of 75.0 % for detecting COVID-19 infection (Table 6).
On the other hand, AUC analysis to determine the accuracy of each parameter in severe group in Table 7, 6 parameters showed a significant result in AUC analysis. However, only IL-6 showed an AUC over 0.8. Indeed, IL-6 was the good biomarker for early COVID-19 diagnosis, reaching an AUC of 0.844. However, IL-6 was the only one presenting an AUC over 0.80, revealing it as the good biomarker to severity COVID-19 (AUC = 0.844 (95% CI [0.783–0.904], P<0.001) (Table 7 and Figure 4C). Moreover, the resulting cut-off value of IL-6 was 51.0 pg/mL, which showed a sensitivity of 100% and specificity of 68% for identifying COVID-19 infection (Table 7). In contrast, 6 parameters in the severe group exhibited a significant result in the area under AUC analysis, which was used to measure the accuracy of each parameter (Table 7).