Herpes Simplex Virus: Cutaneous Manifestations

Overview / Definition Herpes Simplex Virus (HSV) is a member of the Herpesviridae family and is classified into two main types: HSV-1 and HSV-2. HSV-1 primarily causes orofacial lesions, while HSV-2 is predominantly associated with genital infections. Both types can cause cutaneous manifestations and systemic symptoms, leading to recurrent outbreaks. Epidemiology HSV infections are highly prevalent worldwide. The Centers for Disease Control and Prevention (CDC) estimates that approximately 67% of the global population under 50 years old is infected with HSV-1, and around 11% of the population is infected with HSV-2. Key epidemiological points include: Transmission occurs through direct contact with infected lesions, mucosal surfaces, or bodily fluids. HSV-1 is often acquired in childhood, frequently through nonsexual contact. HSV-2 is most commonly transmitted through sexual contact. Pathophysiology / Mechanism After initial infection, HSV establishes latency in the sensory ganglia. Reactivation can occur due to various triggers, leading to recurrent lesions. The pathophysiological mechanisms include: Infection of epithelial cells leading to cell lysis and inflammation. Immune response involving both innate and adaptive systems. Latency established in sensory neurons, allowing for potential reactivation. Clinical Presentation Clinically, herpes simplex manifests in several forms, including: Primary Infection: Often asymptomatic, but may present with fever, malaise, and painful vesicular lesions. Recurrent Herpes: Characterized by localized vesicular eruptions that typically resolve within 1-2 weeks. Common triggers include stress, illness, and sun exposure. Herpetic Whitlow: A painful infection of the fingers caused by HSV. Herpes Gladiatorum: A skin infection seen in wrestlers, characterized by clusters of vesicles. Diagnosis / Workup Diagnosis of herpes simplex is primarily clinical, but laboratory confirmation can be obtained through: PCR Testing: Highly sensitiv