A 54-year-old presents with oral ulcerations. All of the following are reasonable differential diagnoses EXCEPT:

MMP, pemphigus vulgaris, and lupus are chronic immune-mediated conditions that can cause oral ulceration/erosion in a middle-aged adult. Primary herpetic gingivostomatitis is an acute viral infection of children/young adults and is the least fitting differential here.Other options: The three autoimmune/connective-tissue conditions belong in the differential for chronic adult oral ulceration.Key exam takeaway: Chronic immune-mediated oral ulcers in adults: MMP, pemphigus, lupus, lichen planus; primary herpetic gingivostomatitis is an acute pediatric viral disease.