Tetanus

Question 1

What organism causes tetanus?

Answer 1

Clostridium tetani – a gram-positive, motile, spore-forming, obligate anaerobe found in soil and animal feces.

Question 2

What is the toxin responsible for tetanus symptoms?

Answer 2

Tetanospasmin – a neurotoxin that blocks inhibitory neurotransmitters (GABA and glycine), causing continuous muscle contraction and spasms.

Question 3

How do tetanus spores enter the body?

Answer 3

Through contaminated wounds, burns, punctures, umbilical stump infection (neonatal tetanus), or dirty injections under anaerobic conditions.

Question 4

What are the two toxins produced by C. tetani?

Answer 4

Tetanospasmin (neurotoxin) and tetanolysin (causes tissue necrosis and promotes anaerobic growth).

Question 5

What is the incubation period of tetanus?

Answer 5

Typically 7–10 days; shorter incubation indicates higher toxin load and worse prognosis.

Question 6

Describe the pathophysiology of tetanus.

Answer 6

Tetanospasmin travels retrograde along peripheral nerves to the CNS, blocking release of inhibitory neurotransmitters → loss of inhibition → sustained muscle spasms.

Question 7

List the four clinical types of tetanus.

Answer 7

Localized, cephalic, generalized (most common), and neonatal tetanus.

Question 8

What is the most common type of tetanus in children?

Answer 8

Generalized tetanus – presents with trismus, risus sardonicus, opisthotonus, and generalized spasms.

Question 9

What are the early clinical features of tetanus?

Answer 9

Trismus (lockjaw), risus sardonicus (facial grimace), neck stiffness, irritability, and dysphagia.

Question 10

What are the late features of generalized tetanus?

Answer 10

Generalized muscle rigidity, opisthotonus, painful reflex spasms, and laryngeal spasms leading to respiratory compromise.

Question 11

What causes the sustained back arching seen in tetanus?

Answer 11

Opisthotonus – due to spasm of extensor muscles of the back; a hallmark of severe tetanus.

Question 12

What is the most common cause of death in tetanus?

Answer 12

Respiratory failure due to laryngeal spasms and autonomic instability.

Question 13

How is the diagnosis of tetanus made?

Answer 13

It is purely clinical – based on characteristic spasms and rigidity; laboratory confirmation is rarely helpful.

Question 14

List key complications of tetanus.

Answer 14

Respiratory failure, aspiration pneumonia, autonomic instability, fractures from spasms, and rhabdomyolysis.

Question 15

What is the first step in management of tetanus?

Answer 15

Administer Human Tetanus Immune Globulin (TIG) 150 U/kg IM to neutralize unbound toxin as soon as possible.

Question 16

What antibiotic is preferred for tetanus?

Answer 16

Metronidazole for 7–10 days; it kills vegetative forms without affecting GABA, unlike penicillin.

Question 17

Why is penicillin avoided in tetanus treatment?

Answer 17

It inhibits GABA and can worsen muscle spasms and rigidity.

Question 18

How are muscle spasms controlled in tetanus?

Answer 18

Use diazepam (mainstay), midazolam, or chlorpromazine; severe cases may need neuromuscular blockers with mechanical ventilation.

Question 19

What drug helps control both spasms and autonomic dysfunction?

Answer 19

Magnesium sulphate – acts as a muscle relaxant and stabilizes autonomic function.

Question 20

List key supportive care measures in tetanus.

Answer 20

Airway maintenance, quiet environment, adequate nutrition, fluid balance, prevention of bedsores and aspiration, and physiotherapy.

Question 21

What are the goals of tetanus management?

Answer 21

Neutralize toxin, eliminate infection source, control spasms/autonomic symptoms, and provide supportive care.

Question 22

How is the source of infection managed?

Answer 22

Wound debridement to remove necrotic tissue and create aerobic conditions; administer antibiotics (metronidazole).

Question 23

What immunization prevents tetanus?

Answer 23

The DPT vaccine (Diphtheria, Pertussis, Tetanus) given at 6, 10, and 14 weeks, with boosters at 18 months and 5 years.

Question 24

Why should a patient recovering from tetanus still be immunized?

Answer 24

Tetanus infection does not confer immunity, as toxin levels are too low to trigger an immune response.

Question 25

How is neonatal tetanus prevented?

Answer 25

Clean cord care, maternal immunization with tetanus toxoid during pregnancy, and delivery under aseptic conditions.

Question 26

What factors worsen tetanus prognosis?

Answer 26

Short incubation period (<7 days), rapid onset of spasms, presence of autonomic instability, and delayed treatment.

Question 27

What are key exam facts about tetanus management?

Answer 27

Tetanospasmin causes rigidity; treat with TIG + metronidazole + diazepam; metronidazole preferred to penicillin; immunize after recovery.