A 42-year-old woman comes to the emergency department with extensive, painful skin lesions. She is unable to eat or drink due to painful blistering and ulceration in her mouth and throat. The rash was preceded by fever, headache, sore throat, cough, nausea, and vomiting. She was treated for acute cystitis with trimethoprim-sulfamethoxazole 5 days ago, but her history is otherwise unremarkable. Temperature is 38.3 C (101 F), blood pressure is 95/60 mm Hg, pulse is 110/min, and respirations are 14/min. On examination, the skin is hot and tender with widespread confluent erythematous macules that cover most of the visible skin surface on her entire body. The oral mucosa shows blistering and erosions. A representative photograph from her back is shown below. What is the most likely diagnosis?

Question

A 42-year-old woman comes to the emergency department with extensive, painful skin lesions.  She is unable to eat or drink due to painful blistering and ulceration in her mouth and throat.  The rash was preceded by fever, headache, sore throat, cough, nausea, and vomiting.  She was treated for acute cystitis with trimethoprim-sulfamethoxazole 5 days ago, but her history is otherwise unremarkable.  Temperature is 38.3 C (101 F), blood pressure is 95/60 mm Hg, pulse is 110/min, and respirations are 14/min.  On examination, the skin is hot and tender with widespread confluent erythematous macules that cover most of the visible skin surface on her entire body.  The oral mucosa shows blistering and erosions.  A representative photograph from her back is shown below.  What is the most likely diagnosis?

Quizplus · Accepted Answer

Explanation: 11ec25c8_d392_9a93_bc81_bb97220958de_MD0003_00 This patient's clinical features - acute mucocutaneous disorder with associated systemic toxicity, following use of sulfonamide antibiotics - are consistent with toxic epidermal necrolysis (TEN). TEN is an inflammatory hypersensitivity reaction to drugs (especially sulfonamides [eg, trimethoprim-sulfamethoxazole, as in this patient], nonsteroidal antiinflammatory drugs, anticonvulsants and allopurinol) or certain infections (usually Mycoplasma pneumoniae). Clinical features of TEN are variable, but typically include coalescing erythematous macules, bullae, desquamation, and mucositis. Subepidermal and sometimes deeper blistering can be seen. Patches of skin slide off with light pressure (positive Nikolsky sign, also seen in staphylococcal scalded skin syndrome and pemphigus vulgaris). Systemic signs are common and may include fever, tachycardia, hypotension, altered level of consciousness, conjunctivitis, seizures, and coma. The exact pathogenesis is unknown. mucositis TEN and Stevens-Johnson syndrome (SJS) are related disorders and may be considered on a continuum of severity. By convention: SJS denotes involvement of <10% of body surface area (Choice D). TEN denotes >30% involvement (as in this patient with lesions on his oral mucosa, back, and most of the visible skin on her entire body). 10%-30% is referred to as a SJS/TEN overlap syndrome. The treatment of TEN and SJS is primarily supportive, with wound care similar to that for burns (and often provided in a designated burn unit). Aggressive fluid support is often needed due to poor oral intake and profound cutaneous fluid loss. Secondary infections are common, and antiseptic precautions are needed. (Choice A) Erythema multiforme (EM) is characterized by sudden onset erythematous rash and target lesions and usually occurs after a herpes simplex virus infection. EM may appear similar to mild SJS/TEN, but bullae and desquamation are less common, mucosal involvement is rare, and systemic symptoms are not as prominent as in SJS/TEN. target lesions (Choice B) Exfoliative dermatitis (also known as erythroderma) is a widespread, scaly eruption of the skin. It may be drug-induced, idiopathic, or secondary to an underlying dermatological or systemic disease. Exfoliative dermatitis (Choice C) Staphylococcal scalded skin syndrome is a syndrome of acute exfoliation of skin caused by a toxin that is produced by Staphylococcus aureus. The skin is tender and warm, with a superficial, diffuse erythematous rash (in contrast to the deeper erosions in SJS/TEN). Other features include bullae, positive Nikolsky sign, facial edema, perioral crusting, and dehydration. It is usually seen in children age <6 years and is not associated with recent medication use. Educational objective: Toxic epidermal necrolysis (TEN) is a severe syndrome characterized by the sudden onset of mucocutaneous lesions and systemic signs of toxicity. Typical features include an erythematous eruption that rapidly evolves into exfoliation of the skin. It is most often caused by medications (eg antibiotics, anticonvulsants, allopurinol). TEN and Stevens-Johnson syndrome (SJS) are similar disorders distinguished by the percentage of involved skin: SJS involves <10% of the body surface area, TEN involves >30%, and SJS/TEN overlap syndrome involves 10%-30%. References: The current understanding of Stevens-Johnson syndrome and toxic epidermal necrolysis. (http://www.ncbi.nlm.nih.gov/pubmed/22014021)

A 42-Year-Old Woman Comes to the Emergency Department with Extensive