NEET PG High-Yield: Tetanus
A severe neurological disorder caused by the neurotoxin (tetanospasmin) produced by Clostridium tetani. It is non-communicable and preventable via immunization.
| Feature | Details |
|---|---|
| Causative Agent | Clostridium tetani (Gram-positive, anaerobic, spore-forming bacillus). |
| Mechanism | Tetanospasmin blocks the release of inhibitory neurotransmitters (GABA and Glycine). |
| Incubation Period | 3–21 days (usually < 14 days; shorter incubation = worse prognosis). |
Clinical Presentation
- Trismus: Lockjaw (usually the first sign).
- Risus Sardonicus: Characteristic facial expression.
- Opisthotonos: Arching of the back due to muscle spasms.
- Neonatal Tetanus: Typically occurs through infection of the umbilical stump (improper cord care).
High-Yield NEET PG Pearls:
- Prevention: Tetanus Toxoid (TT) vaccination is the cornerstone. Maternal immunization prevents neonatal tetanus.
- Post-Exposure Prophylaxis: Depends on wound severity and patient’s vaccination history (use both Tetanus Immunoglobulin [TIG] and TT for high-risk wounds).
- Treatment: Control spasms (Benzodiazepines), neutralize unbound toxin (TIG), and eradicate the source (Metronidazole).
- Spatula Test: A highly sensitive diagnostic test where stimulating the posterior pharyngeal wall causes a reflex jaw contraction (trismus).