Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)
Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)
Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe and life-threatening mucocutaneous reactions characterized by extensive necrosis and detachment of the epidermis (Hasegawa & Abe, 2020). A typical presentation of a patient with SJS/TEN experience a prodrome period with fever that often is greater than 39 degrees Celsius and generalized influenza-like symptoms of malaise, myalgia, and arthralgia. Other common symptoms include photophobia, conjunctival itching or burning, and pain when swallowing; of which may be indicators of early mucosal involvement. Cutaneous lesions initially begin on the face or trunk of the body, are ill-defined, coalescing, erythematous macules with purpuric centers and are centrally-symmetrically distributed; some cases present with diffuse erythema. As the syndrome progresses, lesions disperse laterally to the extremities and lesions progress to form vesicles and bullae; the scalp is usually not affected, and palms and soles are rarely never involved. The skin is typically tender or painful, and the pain can be out of proportion to the amount of lesions present (High, 2021a). Mucosal lesions or mucosal involvement occur in about 90 percent of cases and can precede or follow the cutaneous lesions; painful crusts and erosions may occur on any mucosal surface. Oral mucus membranes and the vermillion border are frequently involved causing painful hemorrhagic erosions covered with a grayish-white membrane. Stomatitis and mucositis lead to impaired oral intake and subsequent malnutrition and dehydration. Ocular involvement occurs in up to 80 percent of patients, how develop severe conjunctivitis with a purulent discharge; corneal ulceration; and anterior uveitis or panopthalmitis may occur (High, 2021a). Urogenital involvement occurs in up to 67 percent of patients who may develop urethritis, genital erosions, and in women vulvovaginal involvement (erosive and ulcerative vaginitis, vulvar bullae, and vaginal synechiae). The pharyngeal mucosa is affected in nearly all patients (High, 2021a).
Drugs are the leading trigger of SJS/TEN, the most commonly reported medications include allopurinol, aromatic antiseizure medications and lamotrigine, antibacterial sulfonamides (including sulfasalazine), nevirapine, and oxicam nonsteroidal anti-inflammatory drugs (NSAIDs). However, less commonly reported medications include penicillins (amoxicillin or ampicillin) and several conventional and targeted anticancer therapies (High, 2021a).
Differential diagnosis includes erythroderma and erythematous drug eruptions, erythema multiforme, acute generalized exanthematous pustulosis, and generalized bullous fixed drug eruption. Multiple other diagnoses may mimic SJS/TEN, however can be ruled less likely based on patient history. Forming a diagnosis of SJS can be difficult as no universally accepted criteria has been established and a diagnosis would be appropriate based on history and clinical features. SJS and TEN are considered a disease continuum that is differentiated based upon severity and total body percentage affected by blisters and erosions. The less severe form, SJS, is identified by less than 10 percent skin detachment of total body surface area; TEN involves detachment of greater than 30 percent; SJS/TEN overlap describes the in between phase of skin detachment from 10-30 percent (High, 2021a).
One of the most important components of the evaluation is the assessment of the culprit drug. The algorithm of drug causality for epidermal necrolysis (ALDEN) is a screening tool that has found to be useful, especially in patients exposed to multiple medications. When diagnosing SJS/TEN, the assessment of severity is a necessary component. Diagnostics that assist in ruling out other potential causes include a skin biopsy, CBC w/ DIFF, CMP, ESR, CRP, bacterial and fungal cultures from whole blood, wounds, and mucosal lesions, and a chest radiograph SJS/TEN’s patients are at high risk of bacterial superinfections and sepsis (High, 2021b).
The treatment for SJS/TEN first must start with the prompt withdrawal of the culprit drug. Furthermore, care for these patients is predominantly supportive with wound care, fluids and nutrition, pain control, prevention and treatment of infections, and prevention of vulvovaginal sequelae. Beyond supportive care, there are no established therapies for SJS/TEN, the use of corticosteroids, IV IG, cyclosporine, TNF inhibitors, and plasmapheresis remain controversial and continue to be studied (High, 2021b). Appropriate referrals for this population of patients would include a nutrition consult, wound care, ophthalmology, nephrology, and infectious disease. If progression of the disease occurs, supportive measures may include placement of a foley catheter, endotracheal tube, and central venous access.
Reference list
Hasegawa, A., & Abe, R. (2020). Recent advances in managing and understanding Stevens-Johnson syndrome and toxic epidermal necrolysis. F1000Research, 9, 612. https://doi.org/10.12688/f1000research.24748.1
High. (2021a). Stevens-Johnson syndrome and toxic epidermal necrolysis: Pathogenesis, clinical manifestations, and diagnosis. Uptodate. https://www.uptodate.com/contents/stevens-johnson-syndrome-and-toxic-epidermal-necrolysis-pathogenesis-clinical-manifestations-and-diagnosis?search=SJS%2FTEN&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1
High. (2021b). Stevens-Johnson syndrome and toxic epidermal necrolysis: Pathogenesis, clinical manifestations, and diagnosis. Uptodate. https://www.uptodate.com/contents/stevens-johnson-syndrome-and-toxic-epidermal-necrolysis-pathogenesis-clinical-manifestations-and-diagnosis?search=SJS%2FTEN&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1
