Erythema Multiforme Major

An 11-year-old boy presented to the hospital with a 3-day history of maculopapular rash over the face, trunk, and extremities (A, B, and C). He had completed a 5-day course of trimethoprim-sulfamethoxazole for otitis media 1 week before presentation. His medical history was otherwise unremarkable. Over the past 3 days, the rash had become pruritic and the lesions progressively larger. Some lesions were vesicular and bullous. There was diffuse involvement of the oral mucosa, conjunctivae, and genitalia (D).

The patient was admitted to pediatric intensive care with a temperature of 39.4°C (103°F) . Laryngoscopy showed friable oral mucosa and supraglottic edema. The patient was placed in reverse isolation and received wound care, intravenous fluids, and nutrition. An ophthalmologic consultation was requested. Intravenous methylprednisolone was initiated at 1 mg/kg/d and tapered as the patient's condition improved.

Ejaz Nemat, MD, of the University of North Dakota School of Medicine and Health Sciences in Bismarck diagnosed Stevens-Johnson syndrome (SJS). Also known as erythema multiforme major, SJS is an acute, systemic hypersensitivity reaction with involvement of skin and mucous membranes. It is a cell-mediated response to antigenic stimuli, most commonly medications and infective agents. The skin manifestations of the syndrome can be “target” lesions, erythematous papules, or bullae and are typically symmetric. Involvement of extremities and fever are characteristic. Mucous membranes of the conjunctivae, oral mucosa, and genitals are also commonly involved. Adults between age 20 and 40 years are most often affected.

Up to 40% of cases of SJS are idiopathic. Known etiologic factors include viral infection, bacterial infection, and medications. Notable infectious causes include herpes simplex virus, Epstein-Barr virus, and Mycoplasma pneumoniae. Medications most frequently implicated are sulfa drugs, phenytoin, allopurinol, tetracycline, amoxicillin, ampicillin, phenobarbital, carbamazepine, piroxicam, and phenylbutazone.

Anemia and lymphopenia are common laboratory findings. Skin biopsy shows necrosis and vacuolization of basal keratinocytes.

The diagnosis of SJS is clinical. Treatment involves identification of the underlying cause and management of the underlying infection with appropriate antimicrobial therapy. Immediately discontinue any medications implicated.

Management is similar to that for burn victims if skin damage is extensive and if toxic epidermal necrolysis (TEN) develops. Patients with TEN are especially vulnerable to sepsis and fluid and electrolyte disturbances. Local wound care and fluid and electrolyte management are imperative. Empiric antibiotic therapy is not indicated unless secondary infection is present. Oral and ophthalmologic care is mandatory. Systemic corticosteroids are used in most cases and are likely to be most beneficial when initiated early in the course of the disease.