Which viral infection is the most common cause of erythema multiforme?

Erythema multiforme is a condition characterized by the appearance of target-like skin lesions and is often precipitated by infections. The most common viral infection associated with erythema multiforme is herpes simplex virus (HSV).

The association between HSV and erythema multiforme is well-documented, particularly in the form of recurrent outbreaks following HSV infections. This can include both primary and reactivated infections. The mechanism believed to underlie this reaction involves a hypersensitivity response to viral antigens present in the skin.

In contrast, other viral infections listed, such as cytomegalovirus, varicella zoster virus, and human immunodeficiency virus, have not been as directly linked to erythema multiforme. While varicella zoster can cause skin lesions, it is not reported as a common trigger for erythema multiforme compared to herpes simplex. Cytomegalovirus tends to cause more systemic manifestations rather than localized skin reactions. Although HIV can have numerous dermatological manifestations, including reactions related to immune dysfunction, it is also not a primary cause of erythema multiforme.

Understanding the specific relationship between HSV and erythema multiforme can aid in diagnosis and management, emphasizing the