Background: Serum Amyloid A (SAA) is an acute-phase reactant downstream of the pro-inflammatory cytokines released during virus infection. However, the role of this inflammatory marker in SARA-CoV-2 infection is yet to be elucidated. Here, we explored the potential use of SAA in serum as a biomarker for monitoring the clinical course of COVID-19 patients.
Methods: The subjects included 95 COVID-19 patients discharged from the hospital with acute and / or convalescent phases data, among them 69 patients had paired data. Mann-Whitney U statistics and Wilcoxon signed-rank test were used to compare SAA level in the acute and convalescent phases. A subgroup of COVID-19 patients (n=9) participated in a follow-up examination with repeated blood collection reach five times during the hospitalization. The correlations of SAA levels with laboratory testing were then analyzed using the Spearman test.
Results: The results of the data analysis show that the media SAA levels at acute phases were significantly higher (P < 0.05) compared to that at baseline. Furthermore, ascensional range of SAA were associated with the degree of COVID-19 severity. Media SAA levels at convalescent phases were significantly decreased (P < 0.05) compared to that at acute phases. The same phenomenon was seen in patients with and without comorbidities and with fever patients except without fever patients. Furthermore, The SAA concentration change in 9 COVID-19 patients of longitudinal follow-up along with the CT score and SARS-CoV-2 nucleic acid change. In the course of the disease, SAA changes were greater than CRP, lymphocytes, and neutrophils.
Conclusions: The serum SAA levels were found to be significantly correlated with impending course of the COVID-19, and may serve as a useful biomarker to monitor the complicated clinical course of the disease.
