The Great Imitator With a Greater Comeback – A Clinicoepidemiological Study of Syphilis

Introduction: Syphilis is a chronic systemic disease commonly acquired as a sexually transmitted infection and is caused by Treponema pallidum subsp. pallidum. It is one of the ancient diseases known for centuries now. The incidence and prevalence of syphilis worldwide observed a fall during the later part of the 19th century, with increased screening and adequate treatment of positive cases. The increased awareness of safe sexual practices helped reduce disease incidence and transmission. Since 2000, a resurgence has been observed in both developed and developing countries due to a change in sexual behaviour. Objective: To study the present clinico-epidemiological trend of syphilis among patients attending the STD clinic in a tertiary care centre in the Western part of Tamil Nadu. Methodology: A retrospective study of syphilis patients who participated in the Sexually Transmitted Diseases (STD) clinic at the department of Dermatology, Venereology and Leprosy at a tertiary care centre at Coimbatore, Tamil Nadu, for a 1-year duration (June 2022 – July 2023) was conducted. Of the 3119 clients, 170 serologically confirmed syphilis patients were included in our study whose records were analysed for the demographic distribution, clinical stage of syphilis, association with other Sexually Transmitted Infections (STIs) and sexual behaviour. The total number of positive cases was compared with the year-wise positive cases from 2019 to 2023 to study the trend of syphilis. Results: Of the 170 positive cases, males (71.2%) predominated over females (21.8%) and transgenders (7.1%). The most common age group was 21-30 years (52.7%), and presentation was the latent stage of syphilis (46.4%). Men having sex with men (MSM) (40.58%) was the most common high-risk behaviour, followed by heterosexuals (33.52%) and bisexuals (8.23%). Multiple STIs were found in 21.76% cases, of which 67.56% cases were positive for Human Immunodeficiency Virus (HIV) infection. Newly diagnosed HIV disease was found in 14 patients (8.23%), of whom 46.2% were MSM with multiple partners. Interestingly, 7.1% of patients reported usage of social media platforms and apps specially designed for partner selection. It was observed from this study that there is a statistically significant progressive rise in the incidence of syphilis from 1.08% in 2019 to 5.45% in 2023 (p=0.00001; p<.05 is significant). Conclusion: Syphilis, an age-old disease, is alarmingly rising in recent years. Early identification, treatment and preventing further spread depend on focusing on the changing trends of high-risk behaviour of patients and their psychosocial factors and on targeted interventions.