Epidemiological characterization of patients with VDRL test results at the Regional Hospital of Encarnación, Paraguay (2023-2024)
Abstract
Introduction: Syphilis represents a persistent global public health problem. Serological tests, such as VDRL, are essential for initial screening, although they require confirmation by treponemal tests. In Paraguay, there has been an increase in cases, especially among young women.
Objective: To characterize epidemiologically patients with VDRL results at the Regional Hospital of Encarnación, Paraguay, during the period 2023-2024.
Methodology: An observational, descriptive study with correlational analysis was conducted using a cross-sectional design. A total of 22,299 laboratory records of patients over 18 years of age with documented VDRL results were analyzed. Descriptive statistics and the chi-square test were used for bivariate analysis.
Results: A total of 22,298 results were included in the study, and 6.88% (n = 1,534) were VDRL reactive. Most patients were women (78.9%), and the predominant age group was 18-30 years (46.37%). However, reactivity was significantly higher in men (8.37% vs. 6.48%; p<0.001). The most frequent titers were 1:1 (24.90%) and 1:2 (21.84%), which warranted a treponemal test to confirm syphilis. A significant association was found between reactivity and sex, as well as between reactivity and age (p<0.005).
Conclusions: There is a higher frequency of reactive VDRL results in males and young people, highlighting the need for targeted detection, confirmation, and prevention strategies. The implementation of the reverse algorithm is recommended to improve diagnostic sensitivity, especially given the high proportion of low titers.
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