0071643192.pdf

(Barré) #1
INFECTIOUS DISEASE

■ Puncture wounds
■ Wounds with crushed/devitalized tissue
■ Inadequate immunization
■ Produces tetanospasmin
■ Neurotoxin blocks inhibitory nerves
■ Causes overstimulation of
■ Skeletal muscle motor endplates
■ Autonomic nervous system
■ CNS


SYMPTOMS/EXAM


■ Traumatic injury (~30% do not report a specific event)
■ Incubation period: 1 day to >1 month (shorter =more severe)
■ Types:
■ Generalized (#1)
■ Trismus due to masseter spasm (“lockjaw”)
■ Muscle rigidity/spasms
■ Shortest nerves affected first
■ Progresses from head to feet
■ Hydrophobia/drooling
■ Leads to
■ Respiratory failure
■ Autonomic instability
■ Starts in second week
■ Generally hypersympathetic (ie, tachycardia, HTN, diaphoresis)
■ Localized
■ Persistent muscle spasms near site of injury
■ Spontaneously resolves in weeks to months
■ Normally no permanent sequelae
■ Cephalic
■ After head wound or otitis media
■ Cranial nerve dysfunction (most common =CN VII)
■ Neonatal
■ Inadequately immunized mother
■ Unsterile handling of umbilical stump
■ Irritability and poor feeding in first week of life
■ Close to 100% case fatality rate


DIFFERENTIAL


Strychnine poisoning, dystonic reaction, hypocalcemia, encephalitis, menin-
gitis, rabies


DIAGNOSIS


Clinical


TREATMENT


Symptomatic:


■ Aggressive supportive care
■ Benzodiazepines are mainstay for muscle relaxation.
■ Magnesium sulfate will improve spasm control.
■ Labetalol indicated for sympathetic hyperactivity.
■ Avoid isolated β-blockade.


A significant portion of
patients with tetanus do not
report specific trauma.

Strychnine acts by blocking an
inhibitory glycine receptor,
rapidly causes convulsions
and death, and is treated with
benzos and dantrolene.
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