A Previously Healthy 4-Year-Old Boy Is Brought to the Physician

A previously healthy 4-year-old boy is brought to the physician because of blisters and redness on his neck and chest for 2 days. He has also had a fever. He is lethargic and has not eaten well since the rash appeared. He has not had coughing, wheezing, or dysuria. He is an only child and there is no family history of serious illness. His immunizations are up-to-date. His temperature is 38.9°C (102°F) , pulse is 90/min, and blood pressure is 80/40 mm Hg. Examination shows flaccid blisters over his neck and trunk that rupture easily. Areas of erythematous moist skin are also noted. Twirling an eraser over the trunk results in a blister. Oropharyngeal examination is normal. Which of the following is the most likely cause of this patient's symptoms?

A) Autoantibody binding to epithelial cell surface
B) Cell-mediated hypersensitivity
C) Endotoxin-mediated inflammatory response
D) Exotoxin-mediated skin damage
E) Mast cell degranulation