Systemic C-reactive protein levels and central serous chorioretinopathy: A systematic review with meta-analysis

Elevated corticosteroid levels are the strongest known risk factor for central serous chorioretinopathy (CSC), and previous studies have explored if alterations in systemic immunity could play a role in CSC. Here, we explored if elevated systemic C-reactive protein (CRP), a marker of systemic low-grade inflammation, is associated with CSC. We systematically searched 12 literature databases on 12 April 2025 for studies in which blood CRP is measured in both patients with CSC and a comparable control group. Studies were reviewed qualitatively. Meta-analysis using the random-effects model was performed on the weighted mean difference in systemic CRP levels between patients with CSC and controls. Six studies comprising 544 patients with CSC and 655 control individuals were eligible for this review. The meta-analysis of the difference in CRP between patients with CSC and controls showed no statistically significant difference at 0.86 mg/L (95% CI: -1.03-2.75 mg/L; p = 0.37). One study reported a very high degree of association between elevated CRP and CSC, which was not reproduced in the other studies. The lack of association remained consistent in the sensitivity analyses. Current evidence does not suggest that elevated systemic CRP levels are associated with CSC. Further studies on CSC pathophysiology are warranted.