TOXIC EPIDERMAL NECROLYSIS AND STEVENS-JOHNSON SYNDROME
Toxic epidermal necrolysis (TEN) and
Stevens-Johnson syndrome (SJS) are potentially fatal skin disorders and the
most severe form of erythema multiforme. The mortality rate from TEN approaches
30%. Both conditions are triggered by a reaction to medications or result from
a viral infection. Antibiotics, antiseizure agents, bu-tazones, and
sulfonamides are the most frequent medications im-plicated in TEN and SJS (Odom
et al., 2000).
TEN and SJS are characterized initially by
conjunctival burning or itching, cutaneous tenderness, fever, cough, sore
throat, head-ache, extreme malaise, and myalgias (ie, aches and pains). These
signs are followed by a rapid onset of erythema involving much of the skin
surface and mucous membranes, including the oral mucosa, conjunctiva, and
genitalia. In severe cases of mucosal in-volvement, there may be danger of
damage to the larynx, bronchi, and esophagus from ulcerations. Large, flaccid
bullae develop in some areas; in other areas, large sheets of epidermis are
shed, exposing the underlying dermis. Fingernails, toenails, eyebrows, and
eyelashes may be shed along with the surrounding epidermis. The skin is excruciatingly
tender, and the loss of skin leaves a weeping surface similar to that of a
total-body, partial-thickness burn; hence the condition is also referred to as
scalded skin syndrome.
These conditions occur in all ages and both
genders. The in-cidence is increased in older people because of their use of
many medications. People with HIV, particularly those with acquired
immunodeficiency syndrome (AIDS), and others who are im-munocompromised are at
higher risk for SJS and TEN. Although the incidence of TEN and SJS in the
general population is aboutcases per 1 million
person-years, the risk associated with sul-fonamides in HIV-positive
individuals may approach 1 case per 1000 (Odom et al., 2000). Most patients
with TEN have an ab-normal metabolism of the culprit medication, and the
mecha-nism leading to TEN seems to be a cell-mediated cytotoxic reaction
and keratoconjunctivitis are complications of TEN and SJS. Unrecognized and
untreated sepsis can be life-threatening. Keratoconjunctivitis can impair
vision and result in conjunctival retraction, scarring, and corneal lesions.
studies of frozen skin cells from a fresh lesion and cytodiagnosis of
collections of cellular material from a freshly de-nuded area are performed. A
history of ingestion of medications known to precipitate TEN or SJS may confirm
medication reac-tion as the underlying cause.
Immunofluorescent studies may be performed to
detect atypi-cal epidermal autoantibodies. A genetic predisposition to erythema
multiforme has been suggested but is not confirmed for all cases.
goals of treatment include control of fluid and electrolyte balance, prevention
of sepsis, and prevention of ophthalmic com-plications. Supportive care is the
mainstay of treatment.
All nonessential medications are discontinued immediately.
If possible, the patient is treated in a regional burn center, because
aggressive treatment similar to that for severe burns is required. Skin loss
may approach 100% of the total body surface area. Sur-gical d√©bridement or
hydrotherapy in a Hubbard tank (ie, large, steel tub) may be performed to
remove involved skin.
samples from the nasopharynx, eyes, ears, blood, urine, skin, and unruptured
blisters are obtained for culture to identify pathogenic organisms. Intravenous
fluids are prescribed to main-tain fluid and electrolyte balance, especially in
the patient who has severe mucosal involvement and who cannot easily take oral
nourishment. Because an indwelling intravenous catheter may be a site of
infection, fluid replacement is carried out by nasogastric tube and then orally
as soon as possible.
Initial treatment with systemic corticosteroids is
controversial. Some experts argue for early high-dose corticosteroid treatment.
However, in most cases, the risk for infection, the complication of fluid and
electrolyte imbalance, the delay in the healing process, and the difficulty in
initiating oral corticosteroids early in the course of the disease outweigh the
perceived benefits. In patients with TEN thought to result from a medication
reaction, cortico-steroids may be administered; however, the patients should be
closely monitored for the previously stated adverse effects.
report stated that intravenous administration of im-munoglobulin (IVIG) to 10
patients led to improvement within 48 hours and skin healing within 1 week.
This response is dra-matically better than that obtained with
immunosuppressives, and IVIG may soon become the treatment of choice (Rutter
& Luger, 2001).
the skin with topical agents is crucial. Various top-ical antibacterial and
anesthetic agents are used to prevent wound sepsis and to assist with pain
management. Systemic antibiotic therapy is used with extreme caution. Temporary
biologic dress-ings (eg, pigskin, amniotic membrane) or plastic semipermeable
dressings (eg, Vigilon) may be used to reduce pain, decrease evap-oration, and
prevent secondary infection until the epithelium re-generates. Meticulous
oropharyngeal and eye care is essential when there is severe involvement of the
mucous membranes and the eyes.