Chapter 154. Dermatologic Emergencies

Erythema multiforme (EM) strikes all ages, with the highest incidence in young adults (20 to 40 years), affects males twice as often as females, and occurs more commonly in the spring and fall.

Clinical Features

EM is an acute inflammatory skin disease with presentations that range from a mild papular eruption (EM minor) to diffuse vesiculobullous lesions with mucous membrane involvement and systemic toxicity (EM major or Stevens-Johnson syndrome). Precipitating factors include infection (mycoplasma and herpes simplex), drugs (antibiotics and anticonvulsants), and malignancy. No cause is found in about 50% of cases.

Malaise, arthralgias, myalgias, fever, a generalized burning sensation, and diffuse pruritus may precede skin lesions. The initial skin lesions are erythematous papules and maculopapules followed by target lesions in 24 to 48 hours. Urticarial plaques, vesicles, bullae, vesiculobullous lesions, and mucosal (oral, conjunctival, respiratory, and genitourinary) erosions may also develop (Fig. 154-1). Significant systemic toxicity along with significant fluid and electrolyte deficiencies and secondary infection may be seen in severe disease.

Diagnosis and Differential

Target lesions are highly suggestive of EM. The presence of mucosal involvement suggests EM major/Stevens-Johnson syndrome. The differential diagnosis includes herpetic infections, vasculitis, toxic epidermal necrolysis, primary blistering disorders, Kawasaki disease, and toxic infectious erythemas.

Emergency Department Care and Disposition

1. Patients without systemic manifestation and mucous membrane involvement may be managed as outpatients with dermatologic consultation. Systemic steroid bursts (prednisone 60 to 80 milligrams PO daily) are prescribed for mild disease but are unproven to change duration and outcomes. Acyclovir may reduce recurrent HSV-related EM.

2. Patients with extensive disease or systemic toxicity require critical care admission and consultation with a dermatologist and ophthalmologist. Intensive management of fluid, electrolyte, infectious, nutritional, and thermoregulatory issues is required. Diphenhydramine and lidocaine rinses provide symptomatic relief for stomatitis. Cool Burrow solution (5% aluminum acetate) compresses are applied to blistered regions.

Toxic epidermal necrolysis (TEN) is a severe inflammatory skin disease that strikes all ages and both sexes equally. Some authorities consider TEN to be a variant of EM major/Stevens-Johnson syndrome.

Clinical Features

Potential etiologies include medications, chemicals, infections, and immunologic factors. Malaise, anorexia, myalgias, arthralgias, fever, and upper respiratory infection symptoms may precede skin findings by 1 to 2 weeks. Skin findings progress from erythroderma to flaccid bullae to erosions with exfoliation (Fig. 154-2). A Nikolsky sign is present (slippage of the epidermis from the dermis when slight tangential pressure of rubbing is applied). Mucosal lesions are present. Systemic toxicity is common. Acute and chronic complications are similar to those encountered in EM major patients. TEN is fatal in 25% to 35% of cases. Predictors of poor prognosis include advanced age, extensive disease, multiple medication use, leucopenia, azotemia, and thrombocytopenia.

Diagnosis and Differential

Initial diagnosis is based on the clinical features. Definitive diagnosis is made via skin biopsy. The differential diagnosis includes EM major/Stevens-Johnson syndrome, exfoliative erythroderma, primary blistering disorders, Kawasaki disease, and toxic infectious erythemas.

Emergency Department Care and Disposition

1. TEN requires admission to a critical care setting or burn unit with appropriate cardiopulmonary, fluid, electrolyte, and sepsis resuscitation.

2. Emergent dermatologic consultation is required.

Clinical Features

Exfoliative erythroderma is a cutaneous reaction to a drug, chemical, underlying systemic disease state, or skin disorder. Onset may be abrupt (drug, chemical, underlying systemic disease, malignancy) or slow (underlying skin disorder). Symptoms include pruritus, tightening of the skin, and low-grade fever. Skin examination shows acute generalized warmth and erythema, flaking, scaling, and exfoliation. Patients with chronic disease have dystrophic nails, thinning of body hair, alopecia, and diffuse pigmentation changes.

Diagnosis and Differential

Initial diagnosis is based on clinical features. Definitive diagnosis is made via skin biopsy. The differential diagnosis includes EM, TEN, and toxic infectious erythemas.

Emergency Department Care and Disposition

1. Patients with significant disease require emergent dermatologic consultation, a search for the underlying precipitant and admission. Systemic steroids are frequently given after consultation.

2. Correct hypovolemia and hypothermia, if present.

Infectious syndromes caused by toxigenic bacteria with toxin-mediated dermatologic manifestations include staphylococcal toxic shock syndrome (TSS), streptococcal toxic shock syndrome (STSS), and staphylococcal scaled skin syndrome (SSSS). See Chapter 88 for detailed discussion of TSS and STSS.

Clinical Features

Both TSS and STSS present as multisystem illnesses with fever, shock, and erythroderma followed by desquamation. SSSS develops from a toxin produced by Staphylococcus aureus and is seen primarily in infants and young children. The skin is initially tender, with diffuse erythroderma and may have a sandpaper texture. Nikolsky sign is present. Large flaccid bullae then appear followed by sloughing of skin, leaving normal skin in 7 to 10 days (Fig. 154-3)

Diagnosis and Differential

For TSS and STSS, fever and hypotension with associated erythroderma should suggest the diagnosis. The differential diagnosis is broad and includes scarlet fever, Rocky Mountain spotted fever, leptospirosis, rubeola, meningococcemia, SSSS, Kawasaki disease, TEN, Stevens-Johnson syndrome, gram-negative sepsis, and exfoliative drug eruptions. Infants and toddlers with fever and diffuse erythroderma suggest SSSS. The differential diagnosis for SSSS includes TEN, TSS, exfoliative drug eruptions, staphylococcal scarlet fever, and localized bullous impetigo.

Emergency Department Care and Disposition

1. See Chapter 88 for management of TSS and STSS.

2. Patients with diffuse SSSS require aggressive fluid resuscitation, treatment with parenteral antibiotics and admission. Antibiotic choices include nafcillin or oxacillin 2 grams IV every 6 hours (children: 100 milligrams/kilogram/d IV divided every 6 hours). If methicillin resistance is suspected, clindamycin 600 milligrams IV every 6 hours (children: 40 milligrams/kilogram/d IV divided every 6 hours IV) or vancomycin 1 gram IV every 6 hours (in children: 10 to 15 milligrams/killogram IV every 12 hours up to 1 gram) may be added.

Clinical Features

Meningococcemia is a potentially fatal illness caused by Neisseria meningitides that typically affects persons younger than 20 years. Clinical disease usually develops within 3 to 4 days after exposure. Features include severe headache, fever, altered mental status, nausea, vomiting, myalgias, arthralgia, and neck stiffness. Dermatologic manifestations include petechia, urticaria, hemorrhagic vesicles, and macules that evolve into palpable purpura with grey necrotic centers (Fig. 154-4)

Diagnosis and Differential

The diagnosis should be considered in ill-appearing patients with petechial rash and associated symptoms. The differential diagnosis includes Rocky Mountain spotted fever, TSS, gonococcemia, bacterial endocarditis, vasculitis, viral and bacterial infections, and disseminated intravascular coagulation.

Emergency Department Care and Disposition

1. Administer ceftriaxone 2 gram IV and vancomycin1 gram IV as soon as the disease is suspected. The use of steroids is controversial.

2. All patients require close monitoring, supportive care, and hospitalization.

Clinical Features

Pemphigus vulgaris is a generalized, mucocutaneous, autoimmune, blistering eruption with a grave prognosis. Primary lesions are clear, tense vesicles or bullae that vary in diameter, and are first noted on the head, trunk, and mucous membranes. Within 2 to 3 days, the bullae become turbid and flaccid then rupture, producing painful, denuded areas that are slow to heal and prone to secondary infection (Fig. 154-5)

Diagnosis and Differential

Pemphigus vulgaris is suspected by the appearance of lesions and confirmed by skin biopsy and immunofluorescence testing. The differential diagnosis includes bullous pemphigoid, TEN, EM major, dermatitis herpetiformus, and other blistering skin diseases. Bullous pemphigoid is a mucocutaneous blistering disease of the elderly.

Emergency Department Care and Disposition

1. Treat fluid and electrolyte disturbances aggressively.

2. Consult with a dermatologist for management. Corticosteroids and immunosuppressives are the mainstays of therapy. Plasmaphoresis and IV immunoglobins may also be needed.