Antibodies to oxidized low-density lipoproteins in patients with syphilis

Background. The pathogenesis of syphilis is not completely clear. Oxidative stress can play a certain role. Antibodies to oxidized low-density lipoproteins (anti-oxLDL) reflect the level of oxidative stress. Objective. To study the production patterns of antibodies to anti-oxLDL in syphilis, their clinical and laboratory associations, and changes during syphilis therapy. Material and methods. The anti-oxLDL level was measured in 154 patients with various forms of syphilis, of which 57 patients were followed-up. IMTEC-oxLDL-Antibodies Ig(GM) ELISA kits were used to detect anti-oxLDL. Results. Patients with secondary syphilis had the highest levels of anti-oxLDL compared to those with other types. Overall, anti-oxLDL was significantly higher in early syphilis versus untreated late syphilis and untreated late syphilis versus seroresistant patients. In late syphilis, patients with symptoms had higher levels of anti-oxLDL than those without in laboratory-confirmed neurosyphilis. In a multivariate model, the rate of clinical manifestations consistent with neurosyphilis was increased with increased anti-oxLDL level (by 3.8 times), cerebrospinal fluid abnormalities (8.1 times), and no history of syphilis therapy (4.9 times). A higher anti-oxLDL level is associated with a higher titer of microprecipitation test in early syphilis, while in late syphilis, such a relationship was not observed. The level of anti-oxLDL decreased shortly after the start of therapy in patients with early syphilis, and in patients with late syphilis, it decreased slowly and persisted for years. Conclusion. Oxidatively modified LDLs play a significant role in syphilis pathogenesis and the occurrence of complications. Anti-oxLDL can be considered a potential biomarker for assessing immediate treatment outcomes for early syphilis.