Tetanus: Clinical Features, Diagnosis, and Urgent Management

Tetanus is caused by Clostridium tetani neurotoxin (tetanospasmin) blocking inhibitory neurotransmission (GABA/glycine) in spinal cord/brainstem → generalized rigidity and spasms.

Clinical Forms

• Generalized (80%): Trismus (lockjaw), risus sardonicus, opisthotonus, generalized spasms triggered by stimuli.
• Localized: Rigidity/spasms near wound; may generalize.
• Cephalic: Head wound → cranial nerve palsies (CN VII most common).
• Neonatal: Umbilical stump infection; high mortality in unvaccinated populations.

Incubation & Progression

• Incubation: 3–21 days (avg 10); shorter = more severe.
• Onset → full generalization: 1–7 days.
• Autonomic instability: Labile BP, tachycardia, arrhythmias, hyperthermia, sweating.

Diagnosis

• Clinical: No confirmatory lab; spatula test (pharyngeal touch → masseter spasm) supportive.
• Culture: C. tetani from wound (anaerobic) — low sensitivity, not required for treatment.

Urgent Management

1. Airway + ICU: Early intubation if spasms compromise ventilation.
2. Human Tetanus Immune Globulin (HTIG): 3,000–6,000 units IM (separate site from vaccine) — neutralizes unbound toxin.
3. Tetanus Toxoid Booster: 0.5 mL IM (if <3 doses or unknown) — active immunization.
4. Antibiotics: Metronidazole 500 mg IV q6h (preferred) or Penicillin G 2–4M units IV q4h — stops toxin production.
5. Wound Debridement: Excise necrotic tissue, remove foreign material.
6. Spasm Control: Benzodiazepines (diazepam, midazolam) IV; baclofen; neuromuscular blockade (vecuronium) + ventilation if severe.
7. Autonomic Stabilization: Magnesium sulfate, labetalol, clonidine, morphine.

Prevention

• Primary series (DTaP/Tdap) + boosters q10y (Td/Tdap).
• Wound management: Tdap if >5y since last booster (clean minor) or >10y (dirty/complex).

Tetanus is preventable. Vaccination + prompt wound care + HTIG for high-risk wounds = near-zero incidence in immunized populations.