Related Experiment Video
Updated: Aug 20, 2026

Precision Implementation of Minimal Erythema Dose (MED) Testing to Assess Individual Variation in Human Inflammatory Response
Published on: October 3, 2019
Poison ivy: an underreported cause of erythema multiforme
Andrew E Werchniak1, Kathryn Schwarzenberger
1Department of Dermatology, Dartmouth Medical School and Dartmouth-Hitchcock Medical Center, Hanover, New Hampshire, USA.
The relationship between herpes simplex virus (HSV) and erythema multiforme (EM) has been well described. Many authors contend that EM (excluding Stevens-Johnson syndrome and toxic epidermal necrolysis) occurs almost exclusively as a response to HSV infection. During the past year, however, we have observed several cases of EM complicating severe Rhus allergic contact dermatitis. Although this association has been previously documented, the paucity of cases in the literature, along with our experience, suggests that this is an underreported phenomenon. We describe 4 of our cases.
The relationship between herpes simplex virus (HSV) and erythema multiforme (EM) has been well described. Many authors contend that EM (excluding Stevens-Johnson syndrome and toxic epidermal necrolysis) occurs almost exclusively as a response to HSV infection. During the past year, however, we have observed several cases of EM complicating severe Rhus allergic contact dermatitis. Although this association has been previously documented, the paucity of cases in the literature, along with our experience, suggests that this is an underreported phenomenon. We describe 4 of our cases.
Related Concept Videos
Hypersensitivity Reactions: Immune-Complex Reactions
Hypersensitivities
Types of Hypersensitivities
Hypersensitivity reactions are categorized into four types: Type 1, Type 2, Type 3, and Type 4. Each type has a distinct mechanism...
Endocarditis II: Clinical Features of Infective Endocarditis
Myocarditis III: Medical Management
Allergic Drug Reactions
Skin Diseases and Disorders
Gram-positive Staphylococcus spp. and Streptococcus spp. are responsible for many of the most common skin infections. However, many...

