The pattern of cytokines expression and dynamic changes of renal function at 6 months in patients with Omicron COVID-19.

To analyze the dynamic changes of renal function longitudinally and investigate the cytokine profiles at 6 months in patients with Omicron COVID-19. Forty-seven patients with a proven diagnosis of Omicron COVID-19 from January to February 2022 attended a 6-month follow-up after discharge at Tianjin First Central Hospital. The demographic parameters, clinical features, and laboratory indexes were collected during hospitalization and 6 months after discharge. The serum cytokine levels at 6 months were also assessed. Patients were grouped according to with or without kidney involvement at admission. The levels of serum creatinine and estimated glomerular filtration rate (eGFR) were all normal both in the hospital and at follow-up. Whereas, compared with renal function in the hospital, serum creatinine levels at 6 months increased remarkably; meanwhile, eGFR decreased significantly in all patients. The serum levels of interleukin (IL)-2, IL-4, IL-5, IL-6, IL-10, and TNF-α and IFN-γ significantly decreased and TGF-β remarkably increased in the kidney involvement group. The serum levels of IL-2 and IL-5 were positively correlated with age; contrarily, TGF-β showed a negative correlation with aging. The younger was an independent risk factor of the higher TGF-β levels. Omicron patients showed a decline in renal function at follow-up, reflecting the trend of CKD. Serum cytokine profiles were characterized with the majority of cytokines decreased and TGF-β increased in the kidney involvement group; the latter may be used as a sign of CKD. The tendency of CKD is one of the manifestations of long COVID and deserves attention.