A 24 y.o. Asian woman presents with a rash on her palms and soles
What is the rash? what causes it?
Our patient had erythema multiforme minor, in this case probably caused by herpes since she had just had a herpes simplex outbreak. The reaction is thought to be a type IV hypersensitivity reaction caused by viral infections, drugs or skin conditions like psoriasis.
The lesions have a pathognomonic target shape and often begin on the palms and soles or extremities. They last up to two weeks and can recur. In a more serious reaction, erythema multiforme major, blistering can occur with epidermal detachment involving less than 10% of body surface area. The spectrum is completed by TEN(toxic epidermal necrolysis) where more than 30% of the body’s surface area loses skin. Mouth lesions are also noted in the more severe forms as in Stevens Johnson.
While 50% of time erythema multiforme is related to herpes, there are many other causes . When the rash is localized to palms and soles: syphilis, cocksackie virus and Rocky Mountain Spotted fever are in the differential.
Mamatha K, Ravali T, Chiranjeevi P, et al. A case report on ciprofloxacin induced erythema multiforme. 2018 MSRUAS-SAS Tech Journal. Vol 14(2) 45-47.
Lamoreaux M, Sternbach M, Hsu W. Erythema Multiforme. 2006. Am Fam Physician Dec 1;74(11). 1883-88.
Nambudiri V, Nambudiri N, Nazarian R, et al. A rash starting on the palms and soles. 2015 BMJ.