• Many cases preceded by infection with herpes simplex; less often with Mycoplasma pneumoniae or other organisms
• May be related to drug consumption, including sulfonamides, other antibiotics, analgesics, phenolphthalein-containing laxatives, barbiturates
• Another trigger may be radiation therapy.
• Essentially an immunologically mediated reactive process, possibly related to circulating immune complexes
• Acute onset of multiple, painful, shallow ulcers and erosions with irregular margins
• Early mucosal lesions are macular, erythematous, and occasionally bullous.
• May affect oral mucosa and skin synchronously or metachronously
• Lips most commonly affected with eroded, crusted, and hemorrhagic lesions (serosanguinous exudate) known as Stevens-Johnson syndrome when severe
• Predilection for young adults
• As many as one-half of oral cases have associated erythematous to bullous skin lesions.
• Target or iris skin lesions may be noted over extremities.
• Genital and ocular lesions may occur.
• Usually self-limiting; 2- to 4-week course
• Recurrence is common.
• Rapid onset
• Multiple site involvement in one-half of cases
• Biopsy results often helpful, but not always diagnostic
• Viral infection, in particular, acute herpetic gingivostomatitis (Note: Erythema multiforme rarely affects the gingiva.)
• Pemphigus vulgaris
• Major aphthous ulcers
• Erosive lichen planus
• Mucous membrane (cicatricial) pemphigoid
• Mild (minor) form: symptomatic/supportive treatment with adequate hydration, liquid diet, analgesics, topical corticosteroid agents
• Severe (major) form: systemic corticosteroids, parenteral fluid replacement, antipyretics
• If evidence of an antecedent viral infection or trigger exists, systemic antiviral drugs during the disease or as a prophylactic measure may help.
• Generally excellent
• Recurrences common