What Are Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN)?
Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) represent two spectrums of a severe, life-threatening mucocutaneous reaction—most commonly triggered by adverse reactions to prescription medications.
In a textbook chapter published in the European Handbook of Dermatological Treatments, Dr. Grace Obeid and her co-authors outline the clinical features of SJS/TEN: extensive blistering, death (necrosis) of the outer skin layer (epidermis), and painful erosion of mucosal surfaces (eyes, mouth, and genital areas).
SJS vs. TEN: Understanding the Difference
SJS and TEN are variations of the same pathological disease process, differentiated primarily by the percentage of Body Surface Area (BSA) affected by skin detachment:
- Stevens-Johnson Syndrome (SJS): Less than 10% BSA skin detachment.
- SJS / TEN Overlap: 10% to 30% BSA skin detachment.
- Toxic Epidermal Necrolysis (TEN): Greater than 30% BSA skin detachment (requires critical care in a burn or intensive care unit).
High-Risk Medications Associated with SJS/TEN
Over 70% of SJS/TEN cases are directly caused by adverse drug reactions. Symptoms typically appear 7 to 21 days after starting a new medication.
Based on global drug causality assessments (such as the ALDEN algorithm), the most frequently reported culprit medications include:
- Antibacterial Sulfonamides: Such as co-trimoxazole and sulfasalazine.
- Anticonvulsants / Anti-Epileptic Drugs: Including carbamazepine, lamotrigine, phenytoin, and phenobarbital.
- Allopurinol: Commonly prescribed for gout or high uric acid levels.
- Oxicam Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Certain prescription pain relievers.
- Antibiotics: Including aminopenicillins, cephalosporins, and quinolones.
Recognizing Early Symptoms & Warning Signs
Prompt recognition of SJS/TEN can save lives. The condition typically evolves through distinct phases:
1. The Early Prodromal Phase
Days before skin peeling begins, patients often develop non-specific flu-like symptoms:
- High fever, malaise, headache, and body aches.
- Sore throat, painful swallowing, or cough.
- Eye burning, sensitivity to light (photophobia), or conjunctival redness.
2. Mucosal Involvement (Over 90% of Cases)
Painful inflammation and blistering affect mucosal membranes—frequently preceding skin eruptions:
- Oral Mucosa (71–100%): Painful mouth sores, raw gums, and lip ulcers.
- Ocular Mucosa (50–78%): Swollen eyelids, eye discharge, and conjunctival erosion.
- Anogenital Mucosa (40–63%): Painful erosions making urination difficult.
3. Skin Eruption & Blistering
- A reddish, flat, or target-like rash spreads symmetrically across the face, neck, and upper chest.
- Skin becomes extremely tender to the touch.
- Nikolsky Sign: Slight lateral pressure on reddish skin causes the top layer to slide off easily.
- Flaccid blisters form and rupture, leaving exposed, raw skin that resembles “wet cigar paper”.
How SJS/TEN Develops: The Immune Cascade
When a susceptible individual takes a culprit medication, specialized immune cells (CD8+ cytotoxic T-lymphocytes) mistakenly target skin cells (keratinocytes).
These immune cells release cytotoxic proteins—primarily granulysin—which trigger widespread, rapid cell death (apoptosis) across the outer skin layer.
Emergency Management & Treatment Principles
SJS and TEN are medical emergencies requiring immediate hospitalization in specialized burn units or dermatological intensive care units:
- Immediate Withdrawal of Culprit Drugs: Stopping the offending medication as early as possible significantly improves survival rates.
- Supportive Care: Intensive fluid and electrolyte replacement, nutritional support, and environmental temperature control (around 28°C).
- Meticulous Skin & Eye Care: Non-adhesive dressings, petroleum jelly ointments, and daily ophthalmological examinations prevent scarring and long-term vision loss.
- Targeted Systemic Therapies: Promising immunomodulatory therapies—such as cyclosporine—may block disease progression and reduce tissue damage.
Consult Dr. Grace Obeid for Specialist Dermatological Care
Because SJS/TEN requires specialized medical evaluation, consulting an experienced dermatologist is crucial for identifying drug triggers, managing recovery, and avoiding long-term complications.