Stevens-Johnson Syndrome

A 13-year-old boy was brought to the emergency department (ED) with a generalized itchy rash of 2 days' duration. For the past 3 days, he had dry, itchy eyes with a purulent discharge (Figure 1) and nonbilious emesis 2 or 3 times per day, with some blood streaks in the vomitus on the third day of illness. Chills developed on the third day, but the patient's temperature was not measured. His lips were swollen and cracked (Figure 2), which made it painful to eat or drink. About 6 months earlier, he had a similar episode that resolved with application of a topical cream to the lips. He also had painful urination without urgency or penile discharge. He denied recent use of medications and had no ill family members. He had been well before the onset of symptoms.


S Stevens-Johnson syndrome (SJS)
is a dangerous, occasionally fatal rash that can involve skin and mucosa throughout the body. Its exact underlying mechanism remains unknown, but researchers suspect an immune-complexmediated hypersensitivity reaction. Common triggers include certain drugs and infections, but in nearly half of cases, the trigger is unknown. [1][2][3]

(See What can trigger Stevens-Johnson syndrome?)
First identified in 1922, SJS can affect anyone, but it's most prevalent in school-age children and in adults ages 20 through 50, and is twice as likely in males. 3,4 In about 15% of cases, SJS is fatal. 5 A patient's mortality risk depends on how many identified risk factors he has (see Scoring your patient' s prognosis). 3

Signs and symptoms
Patients with SJS may initially experience flulike symptoms, including coughing, headache, myalgia, burning of the eyes, and fever lasting 1 to 14 days. The characteristic rash usually appears 1 to 3 weeks after exposure to the offending trigger.
At first, the rash appears red and papular. Next, target lesions develop: small vesicles (blisters) on an erythematous or dusky purple base. Often, SJS involves bullae (fluid-filled lesions more than 5 mm in diameter) and more atypical target lesions: erythematous or dusky purple but variable in size, confluent (tending to run together), and including vesicles (raised lesions filled with clear fluid and less than 5 mm in diameter). 2,6 The lesions tend to be painful and itchy. They can occur anywhere but are most commonly found on the face, trunk, hands, soles, and anterior aspects of the arms and legs. As the rash spreads, it can cause blistering of all mucous membranes. From 10% to 30% of patients develop lesions in their respiratory and gastrointestinal (GI) tracts. Lesions may also affect the mucosa of the eyes (causing conjunctivitis), mouth (stomatitis), and genitourinary tract (urethritis). Primary skin lesions may necrose or erode, and the patient's lips may develop hemorrhagic crusting and ulcerations. Vesicles typically erupt for 2 to 3 weeks.

Narrowing down the diagnosis
Stevens-Johnson syndrome is diagnosed based on history and clinical presentation. Lab findings may include elevated white blood cell count, elevated erythrocyte sedimentation rate, elevated liver function tests, and a urinalysis with proteinuria, hematuria, and pyuria. 3,6 The SJS rash is sometimes confused with erythema multiforme (EM). However, EM generally causes typical target lesions; SJS is characterized by more atypical target lesions and bullae. Skin lesions in SJS also tend to be more numerous, painful, and pruritic. Mucosal lesions, characteristic of SJS, often are absent in EM. 4 Another similar-looking syndrome is toxic epidermal necrolysis (TEN), which may be a more drastic form of SJS. Although SJS is sometimes called an exfoliating rash, skin involvement in TEN is more severe, with 30% or more of the lesions being bullae with detachment (that is, sloughing). And although TEN often resembles a second-degree burn, SJS looks more like a mix of first-and second-degree burns. Overall mortality is higher with TEN (about 40%). 2,4 The bottom line in recognizing SJS: Has the patient been exposed to a known trigger? And does he have fever, skin lesions, and painful mucosal lesions at two or more sites?
Treating SJS Treatment for SJS, which is mainly supportive, includes withdrawing any offending drug or treatment that may have triggered the syndrome. Ensure rest, optimal pain management and nutritional support, and monitor for secondary infections. Monitor your patient's vital signs and oxygenation and report any abnormal results. Provide meticulous hygiene and wound care as prescribed for the 40 l Nursing2008Critical Care l Volume 3, Number 6 www.nursing2008criticalcare.com

What can trigger Stevens-Johnson syndrome?
In nearly half of all cases, the cause of SJS is unknown. In children, infections and drugs (especially sulfonamides and anticonvulsants) are the most common triggers. In adults, medications are the most common culprit. For some reason-perhaps related to infectious organisms and higher antibiotic use associated with flu season-SJS develops most often in the winter and early spring.

The bottom line in recognizing
Stevens-Johnson syndrome: Has the patient been exposed to a known trigger? patient's skin and mucous membranes. Carefully monitor your patient's fluid intake and output along with dietary intake to ensure that he's getting enough fluid and nutrients.
If mouth ulcerations or GI bleeding prevent the patient from eating, he'll need intravenous (I.V.) fluid and nourishment. He may also require a nasogastric or gastric feeding tube to bypass esophageal strictures or an indwelling urinary catheter if he experiences urethral stricture or painful pruritis. 3,6 Pain medication usually is administered I.V. to avoid the painful swallowing associated with stomatitis. Viscous lidocaine swishes may help relieve mouth pain. Antihistamines can reduce pruritis. 3,6 Antibiotics must be stopped if they're suspected of triggering SJS. But if bacteria (such as Mycoplasma pneumoniae) appear to be the trigger, then the patient will need antibiotics to treat the infection.
Corticosteroids may help by halting the hypersensitivity reaction thought to occur in SJS, but you'll need to monitor your patient for signs of secondary infection and GI hemorrhage.
Research is under way on possible uses of immunoglobulin, cyclosporine, and cyclophosphamide in treating SJS. 7 What more can go wrong? Sloughing of oral and pharyngeal lesions can partially occlude your patient's airway, requiring bronchoscopy or endotracheal intubation. Oral and genital ulcers can open the door to secondary bacterial infections. Skin necrosis and erosion may need to be treated with skin grafting. 1,3,6 Besides impairing respiratory function, M. pneumoniae can increase the likelihood of rare complications such as hepatitis, GI bleeding, nephritis, and acute renal failure. Although patients with SJS rarely require intubation for secondary pneumonia or bronchitis, monitor for signs of deteriorating respiratory function, such as tachypnea, tachycardia, change in mentation, and falling SpO 2 or SaO 2 . Respiratory ausculatory findings with M. pneumoniae include scattered crackles and wheezes without evidence of consolidation.
Ocular complications can include keratitis, corneal scarring, perforation of the globe (rare), adhesions of the eyelids, and-in up to 10% of patientsblindness. Skeletal and muscle problems may include arthritis, arthralgia, and myalgia. 1,3,6 Explain to your patient and his family that SJS is a slow-resolving syndrome and that the most important goals are comfort, pain control, adequate nutrition, and preventing complications. Tell your patient to report any fever, tachypnea, or tachycardia, as these may indicate a secondary infection.

Scoring your patient's prognosis
To assess a patient's risk of death from Stevens-Johnson syndrome (or from toxic epidermal necrolysis), calculate his SCORTEN score based on the factors below. Score 1 point for each criterion your patient has: • age 40 years or older • diagnosis of cancer • heart rate 120 beats/minute or greater • 10% skin detachment from bullae initially • blood urea nitrogen level greater than 10 mmol/L • serum glucose level greater than 14 mmol/L • bicarbonate level of less than 20 mmol/L. Based on his score, the patient's risk of death is as follows: 0-1 = 3.2% or more, 2 = 12.1% or more, 3 = 35.3% or more, 4 = 58.3% or more, and 5 or greater = 90% or more.
Besides impairing respiratory function, Mycoplasma pneumoniae can increase the likelihood of rare complications such as hepatitis, GI bleeding, nephritis, and acute renal failure.
hours of onset can hasten recovery from SJS. Even dire cases can have good outcomes. One such case involved a 15-year-old girl diagnosed with SJS secondary to M. pneumoniae. She survived despite respiratory distress that required mechanical ventilation, acute renal failure that required hemodialysis, and numerous skin graft surgeries. Today, my former patient is a physician herself-and always alert when a patient presents with typical and atypical target skin lesions and mucosal lesions. O