TEN; This is literature-spontaneous report. A 19-year-old woman with no significant past medical history presented to dermatology clinic for evaluation of a 5-day history of a bullous rash and painful oral lesions. The rash started on her left upper arm 8 days after receiving a vaccine for meningococcus B (TRUMENBA) in her left deltoid, before spreading to her face, torso, legs, and neck. The patient denied fevers, malaise, or recent preceding illnesses. She was in the final days of completing a 3-week course of omeprazole for gastritis, but otherwise denied intake of any other medications, herbs, or supplements. On initial examination by the dermatology consultant (day 13 post-vaccination), the patient had evidence of tense bullae and violaceous targetoid plaques on her face, neck, trunk, and bilateral upper and lower extremities; she also exhibited erosions involving the mucosal lips. At that time, erythema multiforme major was favored over SJS or TEN given the targetoid nature of the majority of her lesions. The patient was started on empiric valacyclovir, doxycycline, and oral prednisone. A shave biopsy was performed on the left upper arm and showed marked interface dermatitis with numerous scattered necrotic keratinocytes and a superficial perivascular lymphocyte-predominant inflammatory infiltrate. IgM and PCR for HSV-1 and HSV-2 as well as IgM for Mycoplasma pneumoniae were negative. Two days after outpatient evaluation the patient was admitted to the hospital owing to progression of the rash. The patient now had nearly 80% body surface area (BSA) involvement with dull erythematous targetoid macules, some with overlying intact annular bullae; she had epidermal detachment of 30% of her BSA. The patient also had superficial erosions and crusting noted on her lips, vaginal mucosa, and perianal area. Her corresponding SCORTEN score was 1, with an associated mortality risk of 3.2% (SCORTEN criteria = age more than 40, associated malignancy, heart rate more than 120, serum BUN more than 28 mg/dL, detached BSA more than 10%, serum bicarbonate less than 20 mEq/L, serum glucose more than 252 mg/dL). Infectious studies for HSV and Mycoplasma were repeated upon admission and again were negative. Chest X-ray did not reveal any abnormalities. Over the next two days, the patient developed conjunctival injection and the eruption became more confluent and dusky; desquamation was observed. Owing to concern for possible toxic epidermal necrolysis, a one-time dose of etanercept 50mg/mL was administered to the left upper arm. Within one day the rash had stabilized and was less symptomatic. By three days there was evidence of reepithelialization. The patient was discharged 7 days after receiving etanercept. The authors also hypothesize that a combination antigen could have resulted in TEN in this patient, since she was taking omeprazole at the same time she received the meningococcal vaccination.   No follow-up attempts are needed. No further information is expected.; Sender's Comments: The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to Regulatory Authorities, Ethics Committees, as appropriate. The case will be reassessed if additional information becomes available.