Toxin-Mediated Erythema

June 12, 2018

F. Hall Reynolds II, MD, MSc; Mark G. Tusa, MD; and Samuel L. Banks, MD
Chattanooga Skin and Cancer Clinic, Chattanooga, Tennessee

Reynolds FH II, Tusa MG, Banks SL. Toxin-mediated erythema [published online June 11, 2018]. Consultant for Pediatricians.


Human illness due to protein toxin pose a formidable diagnostic dilemma. Increasing numbers of illnesses are being attributed to relate to toxins (bacterial or viral polypeptides) and relate to host susceptibility, microbial virulence, and perhaps new toxins being produced or identified. White and colleagues1 in 1989 introduced the concept that a protein toxin may function as a superantigen and activate excessive numbers of T lymphocytes. Since then, increasing numbers of illnesses have been attributed to toxins acting as superantigens. Clinical illnesses caused by streptococcal or staphylococcal toxins/superantigens may present similarly and are attributed to structural similarity of toxin molecules, with 3-dimensional structure being more important than amino acid sequence.2-5

Patients who present with erythema of both the perineal skin and the mucosa are a diagnostic challenge. Their skin abnormalities may represent an easily treated dermatitis or the early stages of a life-threatening illness. Clinical acumen is critical in solving the dilemma.


A 4-year-old boy had been in his usual state of good health until experiencing what had been considered to be a cold. Skin redness was noted in the distribution of his underwear, which prompted a visit to our general dermatology office a few days later. The redness had not caused itching or pain, nor had it interfered with bodily functions. There had been no systemic involvement such as fever, headache, loss of energy, irritability, or diarrhea.

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