Avaliação do perfil de citocinas na uveíte sifilítica e suas correlações clínicas

Abstract

Introduction: syphilis is a sexually transmitted infection caused by Treponema pallidum and has a pleomorphic clinical presentation. Its incidence has increased significantly over the last two decades, with a subsequent increase in the number of cases of syphilitic uveitis. Ocular syphilis, despite being an infrequent form of presentation, can lead to visual sequelae. The role of cytokines in the immunocellular response is not completely understood in this infection, and there are gaps in the understanding of its pathophysiology. Objectives: to characterize the cytokine profile in peripheral blood plasma and aqueous humor of patients with syphilitic uveitis, compare with individuals without ocular disorders, and to correlate it with clinical parameters. Methods: this is a comparative interventional cross-sectional study conducted with individuals who had a clinical-serological diagnosis of syphilitic uveitis in the uveitis service of HC-UFMG, from March 2022 to April 2023. During this period, 15 patients were included in the case group and 20 patients recruited for the control group. Complete ophthalmological examination was carried out, aqueous humor and peripheral blood were collected from all participants, with subsequent measurement of cytokines in the collected fluids. Statistical analysis compared the concentration of cytokines and variables of interest between groups using non-parametric tests, adopting a statistical significance level of 5%. Results: the clinical-epidemiological analysis of the cases revealed a predominance of male patients (66.7%) in the fifth decade of life and a majority of black or mixed-race individuals (80%). HIV co-infection rate was 13.3% and the majority of patients were identified as heterosexual (86.7%). Analysis of the concentration of cytokines in plasma revealed difference, with increase in the levels of CXCL10 and CCL4, in relation to the control group. When evaluating the aqueous humor of the cases, a higher concentration of Th1 (IFN-g; IL-2 e TNF-a), Th2 (IL-4; IL-5; IL10; IL-13), Th17 (IL-17) cytokines and chemokines (CXCL10; CCL3; CCL4 e CCL5) was observed, when compared to the control group. Furthermore, there was a difference in the concentration of cytokines in the aqueous humor of patients depending on the systemic phase of syphilis. Conclusion: cases of syphilitic uveitis have higher concentrations of cytokines in aqueous humor than the control group, suggesting a localized inflammatory process, however with no distinct immunoinflammatory response profile. Correlation of cytokines with clinical parameters was limited by the sample size and cross-sectional design of the study. Therefore, there is a demanding need for longitudinal studies to better understand the immunoinflammatory response in ocular syphilis.