Board Review: Sexually Transmitted Infections with Dermatologic Features
Sexually transmitted infections (STIs) often present with notable dermatologic features, making dermatologists key players in their diagnosis and management. This article reviews common STIs with cutaneous manifestations, focusing on their clinical presentations, diagnostic approaches, and treatment options.
Topics: STI, syphilis, board review
Overview / Definition Sexually transmitted infections (STIs) are infections that are primarily transmitted through sexual contact. Some STIs have significant dermatologic features that can aid in their diagnosis. Common examples include herpes simplex virus (HSV), human papillomavirus (HPV), syphilis, and human immunodeficiency virus (HIV). Epidemiology The prevalence of STIs varies significantly by geographic region, population, and sexual behaviors. According to the World Health Organization (WHO), STIs are among the most common infectious diseases worldwide, with millions of new cases reported each year: Chlamydia trachomatis: Most prevalent bacterial STI, with higher rates in young adults. Human papillomavirus (HPV): Over 80 million Americans are currently infected; a significant proportion of sexually active individuals will contract HPV at some point in their lives. Syphilis: Incidence has increased, particularly among men who have sex with men (MSM). Herpes Simplex Virus (HSV): Affects approximately 1 in 6 individuals aged 14 to 49 in the United States. Pathophysiology / Mechanism STIs affect the skin and mucous membranes through various mechanisms, depending on the causative organism. For instance: HSV: Causes vesicular lesions through direct viral replication in epithelial cells. HPV: Leads to the proliferation of keratinocytes, resulting in warty lesions. Syphilis: The Treponema pallidum bacterium invades tissues, leading to systemic spread and characteristic lesions. Clinical Presentation The clinical manifestations of STIs can vary widely: Herpes Simplex Virus: Painful vesicular lesions on the genitals or oral mucosa. Human Papillomavirus: Genital warts (condylomata acuminata) often present as cauliflower-like lesions. Syphilis: Chancre in primary syphilis; rash in secondary syphilis, often described as a non-itchy, generalized rash. HIV: Acute HIV infection may present with generalized rash, mucosal ulcerations, and lymphadenopathy. Diagnosis / Workup D