Study Notes: Stevens-Johnson Syndrome (SJS) | Drugs Causing Stevenson Johnson Syndrome | Tricks and Mnemonics | Pharmacology
Definition:
Stevens-Johnson Syndrome is a severe mucocutaneous hypersensitivity reaction characterized by epidermal necrosis and detachment, usually involving <10% of body surface area (BSA).
🔬 Etiology/Triggers:
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Drugs (most common cause)
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Infections: Mycoplasma pneumoniae, HSV
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Idiopathic
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Malignancies, vaccines (rare)
💊 Common Drugs Causing SJS:
Use the mnemonic: “LAME PCS”
| Drug/Class | Examples |
|---|---|
| L – Lamotrigine | Antiepileptic |
| A – Allopurinol | Gout treatment |
| M – Modafinil / Methotrexate | CNS stimulant / DMARD |
| E – Ethosuximide | Antiepileptic |
| P – Phenytoin / Phenobarbital | Antiepileptics |
| C – Carbamazepine | Antiepileptic |
| S – Sulfa drugs | Sulfonamides, Sulfasalazine |
✅ Also includes:
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Penicillins, Cephalosporins, NSAIDs (esp. Oxicams), Nevirapine, Abacavir, Tetracyclines
- Important Books for GPAT
🧬 Genetic Risk Factors:
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HLA-B*15:02 → Carbamazepine-induced SJS (Asians)
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HLA-B*58:01 → Allopurinol-induced SJS
🔍 Clinical Features:
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Fever, malaise
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Painful erythematous macules → bullae → skin detachment
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Mucosal involvement (oral, ocular, genital)
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Nikolsky sign positive
🧪 Diagnosis:
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Clinical diagnosis
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Skin biopsy (keratinocyte necrosis)
💊 Management:
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Stop offending drug immediately
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Supportive care (ICU/burn unit)
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Fluids, wound care
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Pain control, antiseptics
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Systemic corticosteroids / IVIG / immunosuppressants (controversial)
✅ Multiple Choice Questions (MCQs)
Participate in GPAT MOCK Test
🧠 Q1. Which of the following is most commonly associated with Stevens-Johnson Syndrome?
A. Atenolol
B. Allopurinol
C. Ranitidine
D. Metformin
Answer: ✅ B. Allopurinol
🧠 Q2. Which HLA allele is associated with increased risk of SJS due to carbamazepine in Asians?
A. HLA-B57:01
B. HLA-B15:02
C. HLA-A33
D. HLA-B58:01
Answer: ✅ B. HLA-B*15:02
🧠 Q3. All of the following drugs can cause SJS EXCEPT:
A. Sulfonamides
B. Phenytoin
C. Azithromycin
D. Carbamazepine
Answer: ✅ C. Azithromycin (rarely associated, not common culprit)
🧠 Q4. Which of the following features is least likely in Stevens-Johnson Syndrome?
A. Skin blistering
B. Mucosal erosions
C. Rapid resolution without treatment
D. Nikolsky sign positive
Answer: ✅ C. Rapid resolution without treatment
🧠 Q5. A 23-year-old patient develops fever, mucosal ulcers, and skin detachment after starting a new antiepileptic. The most likely drug is:
A. Sodium valproate
B. Ethosuximide
C. Lamotrigine
D. Diazepam
Answer: ✅ C. Lamotrigine