The severe acute respiratory syndrome coronavirus 2, SARS-CoV-2, was first discovered in Wuhan, Hubei province, China. Cytokines play a critical role in COVID-19 infections through their inflammatory or anti-inflammatory activities. This study aimed to detect the diagnostic value of and the relationship between the interleukins under study, in addition to their relationship with demographic data in COVID-19 patients. Patients with a confirmed diagnosis of COVID-19 based on laboratory (PCR) results and the healthy control group were given their section of this investigation. The patient group had 120 COVID-19 patients, including 62 males and 58 females, while the control group consisted of 32 individuals (22 males and 10 females). The subdivision was then performed according to their vaccination status, chronic diseases, gender, and residence. Cytokine levels were detected using the ELISA technique. The immunological status of COVID-19 patients was determined by measuring interleukin (IL)-6, IL-25, and IL-35. During the research, it was found that IL-6 was highly significant in COVID-19 patients (0.001). However, its level was not significantly different (0.376) in patients regarding the type of chronic diseases, residence (0.353), and gender (0.574), but it was significantly different in vaccinated patients (0.029). It was also found that IL-6 is significantly correlated with IL-25 and IL-35. IL-25 was highly significant in COVID-19 patients (0.007), and there was a significant difference in its level in patients regarding the type of chronic disease (0.049). While there was no difference in terms of residence (0.421) and gender (0.681), corona vaccination showed a significant difference (0.047). IL-25 also had a significant correlation with IL-6 and IL-35. As for IL-35, it was significant in patients with COVID-19 (0.013) but not significantly different regarding chronic diseases (0.344), residence (0.877), or gender (0.800). However, it was significantly different in vaccinated patients, compared to the non-vaccinated ones. IL-35 was found to be significantly correlated with IL-25 and IL-6 (0.000). The examined interleukins increased in COVID-19 individuals. IL-6 remains an excellent marker for determining the immune state of patients with COVID-19. There were also strong correlations between the interleukins under study in COVID-19 patients. However, there was no relationship between age, residence, gender, and the concentration of studied cytokines. IL-25 increases significantly in COVID-19 patients suffering from chronic diseases. Therefore, it is more efficient in the follow-up of patients.
Keywords: Cytokines; Interleukins; SARS-CoV-2.