Tetanus Flashcards
Centers for Disease Control and Prevention defines tetanus as
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
True or false
Tetanus among children and neonatal tetanus are uncommon
True 
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
 True
C. tetani produces two exotoxins:
tetanolysin
tetanospasmin
Exotoxin which facilitates growth of the bacterial population
tetanolysin
powerful neurotoxin responsible for all of the clinical manifestations of tetanus
tetanospasmin
How does tetanospasmin reach into the CNS?
- hematogenous spread of the exotoxin to peripheral nerves and
- retrograde intraneuronal transport
True or false
Tetanospasmin does not cross the blood–brain barrier
True
Mechanism of action of tetanospasmin
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
True or false
No wound exists in up to 10% of patients with tetanus
 True
The incubation period for tetanus ranges
<24 hours to >1 month
True or false
Short incubation periods are associated with severe disease and a poor prognosis
True
Less likely causes
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
Three forms of tetanus
generalized, cephalic, and local
accounts for about 80% of cases
Generalized tetanus
most frequent presenting complaints of patients with generalized tetanus
Pain and stiffness in the masseter muscles (“lockjaw”)
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.
 True
transition from muscle stiffness to rigidity leads to the development of trismus and the characteristic facial expression called
risus sardonicus (sardonic smile)
Spasms can last for
3 to 4 weeks
Recovery depends on
regrowth of axonal nerve terminals and may take months
an important consideration in differentiating tetanus from other disorders
The mental status is normal
Complications of tetanus
- rhabdomyolysis
- long- bone fractures secondary to violent muscle contractions.
True or false
Aspiration pneumonia is present in 50% to 70% of autopsied cases.
True
What occurs during the second week of clinical generalized tetanus?
Autonomic dysfunction and a hypersympathetic state including tachycardia, labile hypertension, profuse sweating, hyperpyrexia, and increased urinary excretion of catecholamines
Neonatal tetanus
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
Cephalic tetanus
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.
Local tetanus
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.
True or false
Tetanus is a clinical diagnosis
True
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.
True 
True or false
There are no laboratory tests to diagnose tetanus, although serum antitoxin titers of >0.01 IU/mL are usually protective.
 True
True or false
Human tetanus immunoglobulin neutralizes circulating tetanospasmin and toxin in the wound but not toxin already fixed in the nervous system.
 True
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.
3000 to 6000 units IM
True or false
Give tetanus immunoglobulin before wound debridement because exotoxin may be released during wound manipulation
 True
antibiotic of choice
metronidazole, 500 milligrams IV every 6 to 8 hours
the preferred benzodiazepine for treatment of tetanus because of cost and availability
Diazepam
neuromuscular blockade what can be given?
- Succinylcholine -given early for emergency airway control
- vecuronium- for prolonged blockade, with minimal cardiovascular side effects.
Contraindications to tetanus-diphtheria or Tdap
- history of serious allergic reaction (respiratory compromise or cardiovascular collapse) to vaccine components.
- 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
- Guillain-Barré syndrome ≤6 weeks after a previous dose of tetanus toxoid-containing vaccine,
- moderate to severe acute illness,
- unstable neurologic condition, or
- history of an Arthus reaction to a tetanus toxoid–containing vaccine administered <10 years previously.
True or false
If tetanus toxoid is contraindicated, consider passive immunization with tetanus immunoglobulin
True
