Tetanus

Question 1

Centers for Disease Control and Prevention defines tetanus as

Answer 1

syndrome of acute onset of hypertonia and/or painful muscular contractions (usually of the muscles of the jaw and neck) and generalized muscle spasms without other apparent medical cause

Question 2

True or false

Tetanus among children and neonatal tetanus are uncommon

Answer 2

True 

Question 3

True or false

Crushed or devitalized tissue, a foreign body, or the development of infection favors the growth of the toxin- producing form of C. tetani

Answer 3

 True

Question 4

C. tetani produces two exotoxins:

Answer 4

tetanolysin

tetanospasmin

Question 5

Exotoxin which facilitates growth of the bacterial population

Answer 5

tetanolysin

Question 6

powerful neurotoxin responsible for all of the clinical manifestations of tetanus

Answer 6

tetanospasmin

Question 7

How does tetanospasmin reach into the CNS?

Answer 7

1. hematogenous spread of the exotoxin to peripheral nerves and
2. retrograde intraneuronal transport

Question 8

True or false

Tetanospasmin does not cross the blood–brain barrier

Answer 8

True

Question 9

Mechanism of action of tetanospasmin

Answer 9

Tetanospasmin prevents the release of the inhibitory neurotransmitters glycine and γ-aminobutyric acid from presynaptic nerve terminals, releasing the nervous system from its normal inhibitory control.

Loss of inhibition may also affect the preganglionic sympathetic neurons, resulting in sympathetic overactivity and high circulating catecholamine levels

Question 10

True or false

No wound exists in up to 10% of patients with tetanus

Answer 10

 True

Question 11

The incubation period for tetanus ranges

Answer 11

<24 hours to >1 month

Question 12

True or false

Short incubation periods are associated with severe disease and a poor prognosis

Answer 12

True

Question 13

Less likely causes

Answer 13

Tetanus can also develop after surgical procedures, otitis media, or abortion and can develop in injection drug users from contaminated heroin and in neonates through infection of the umbilical stump

Question 14

Three forms of tetanus

Answer 14

generalized, cephalic, and local

Question 15

accounts for about 80% of cases

Answer 15

Generalized tetanus

Question 16

most frequent presenting complaints of patients with generalized tetanus

Answer 16

Pain and stiffness in the masseter muscles (“lockjaw”)

Question 17

True or false

Nerves with short axons are first involved, with symptoms in the facial muscles; later, descending progression to the muscles of the neck, trunk, and extremities occurs.

Answer 17

 True

Question 18

transition from muscle stiffness to rigidity leads to the development of trismus and the characteristic facial expression called

Answer 18

risus sardonicus (sardonic smile)

Question 19

Spasms can last for

Answer 19

3 to 4 weeks

Question 20

Recovery depends on

Answer 20

regrowth of axonal nerve terminals and may take months

Question 21

an important consideration in differentiating tetanus from other disorders

Answer 21

The mental status is normal

Question 22

Complications of tetanus

Answer 22

1. rhabdomyolysis
2. long- bone fractures secondary to violent muscle contractions.

Question 23

True or false

Aspiration pneumonia is present in 50% to 70% of autopsied cases.

Answer 23

True

Question 24

What occurs during the second week of clinical generalized tetanus?

Answer 24

Autonomic dysfunction and a hypersympathetic state including tachycardia, labile hypertension, profuse sweating, hyperpyrexia, and increased urinary excretion of catecholamines

Question 25

Neonatal tetanus

Answer 25

a form of generalized tetanus, develops in infants born to inadequately immunized mothers, frequently after unsterile treatment of the umbilical cord stump.

Infants with neonatal tetanus are weak, irritable, and have an inability to suck.

Symptoms are evident by the second week of life

Question 26

Cephalic tetanus

Answer 26

follows injuries to the head or occasionally otitis media and results in dysfunction of the cranial nerves, most commonly the seventh. It has a poor prognosis.

Question 27

Local tetanus

Answer 27

displays muscle rigidity in proximity to the site of injury and usually resolves completely after weeks to months. Local teta- nus may progress to the generalized form of the disease. Approximately 1% of these cases are fatal.

Question 28

True or false

Tetanus is a clinical diagnosis

Answer 28

True

Question 29

True or false

Wound culture is of limited value because C. tetani may be cultured from wounds in the absence of clinical disease and may not be recovered in patients with documented tetanus.

Answer 29

True 

Question 30

True or false

There are no laboratory tests to diagnose tetanus, although serum antitoxin titers of >0.01 IU/mL are usually protective.

Answer 30

 True

Question 31

True or false

Human tetanus immunoglobulin neutralizes circulating tetanospasmin and toxin in the wound but not toxin already fixed in the nervous system.

Answer 31

 True

Question 32

For the treatment of clinical tetanus, the optimal dose of tetanus immunoglobulin is unknown, but ______________is the usual recommended dose, administered in a separate syringe and opposite the site of tetanus toxoid administration.

Answer 32

3000 to 6000 units IM

Question 33

True or false

Give tetanus immunoglobulin before wound debridement because exotoxin may be released during wound manipulation

Answer 33

 True

Question 34

antibiotic of choice

Answer 34

metronidazole, 500 milligrams IV every 6 to 8 hours

Question 35

the preferred benzodiazepine for treatment of tetanus because of cost and availability

Answer 35

Diazepam

Question 36

neuromuscular blockade what can be given?

Answer 36

1. Succinylcholine -given early for emergency airway control
2. vecuronium- for prolonged blockade, with minimal cardiovascular side effects.

Question 37

Contraindications to tetanus-diphtheria or Tdap

Answer 37

1. history of serious allergic reaction (respiratory compromise or cardiovascular collapse) to vaccine components.
2. History of encephalopathy (e.g., coma or prolonged seizures) not attributable to an identifiable cause within 7 days of administration of a pertussis vaccine is a contraindication to Tdap.

Reasons to defer tetanus-diphtheria or Tdap include

1. Guillain-Barré syndrome ≤6 weeks after a previous dose of tetanus toxoid-containing vaccine,
2. moderate to severe acute illness,
3. unstable neurologic condition, or
4. history of an Arthus reaction to a tetanus toxoid–containing vaccine administered <10 years previously.

Question 38

True or false

If tetanus toxoid is contraindicated, consider passive immunization with tetanus immunoglobulin

Answer 38

True