Stevens-Johnson syndrome (SJS) is most commonly caused by certain medications that trigger an immune reaction. The main medication causes include antibiotics (especially sulfa drugs), anticonvulsants (such as lamotrigine, carbamazepine, and phenytoin), allopurinol, and some pain relievers. Infections, particularly certain viral infections like Mycoplasma pneumoniae and cytomegalovirus, can also cause SJS. Genetic predispositions and immune system disorders like HIV/AIDS or lupus increase the risk. The syndrome is essentially a severe immune hypersensitivity reaction affecting skin and mucous membranes.
Medication Causes
- Antibiotics: sulfonamides, penicillins, ciprofloxacin
- Anticonvulsants: lamotrigine, carbamazepine, phenytoin, valproic acid
- Other drugs: allopurinol, NSAIDs, acetaminophen, nevirapine, and several others
- Symptoms typically begin within 4 to 28 days of starting the causative drug.
Infection Causes
- Viral infections like herpes simplex virus, Epstein-Barr virus, enteroviruses
- Bacterial infections such as group A beta-hemolytic streptococci and Mycoplasma pneumoniae
- Fungal and protozoal infections are also possible triggers.
Immune Reaction
SJS is a type IV hypersensitivity reaction where the immune system attacks the body's own skin and mucous membranes, primarily mediated by activated T cells and natural killer cells.
In summary, SJS is caused by medications or infections triggering a severe immune reaction, often influenced by genetic and immune system factors.