Bacterial Diseases Flashcards
what is tetanus?
An acute infectious disease caused by
spores from the bacterium
Clostridium tetani
what type of bacteria is c. tetani?
anaerobic, gram-positive
bacillus
appearance of c. tetani
“drum stick” appearance
transmission of c. tetani
- spores found everywhere in environment
- develop into bacteria when it enters the body (usu through breaks in the skin)
what is unique about tetanus?
although it’s preventable w/ vaccine, it’s not spread person to person
c. tetani pathogenesis
- spores colonize a deep puncture wound
- in the presence of anaerobic conditions, it produces tetanus toxins
- diffuses away from the would and enters the blood stream and lymph system
- toxins act on neurons that control the nueral feedback that tells flexed musces to relsx
- prevents theses neurons from signaling the relaxation
incubation period of c. tetani
3-21 days (avg. 5-10)
3 clinical forms of tetanus
- generalized
- localized
- cephalic
generalized tetanus s/sx
- MC
- spasm of masseter (lockjaw)
- HA
- muscle spasms
- jerking or staring
- dysphagia/drooling
- painful muscle stiffness
- diaphoresis
localized tetanus s/sx
-muscle spasms in a confined area close to the site of the injury
cephalic tetanus s/sx
- assocated w/ lesions of the head/face and OM
- results in flaccid cranial nerve palsies rather than spasm
dx of tetanus
clinical - no lab tests
tx of tetanus
- medical emergency
- immediate tx w/ human tetanus immune globulin (TIG)
- agents for muslce spasms
- aggressive wound care
- IVIG can be used
prognosis of tetanus
-mortality: worldwide - 50%; untreated adults - 15-60%; neonates - 80-90%
how long does the tetanus vaccine last?
10 yrs
what is diptheria?
Diphtheria is an infection
caused by the
Corynebacterium
diphtheriae bacterium
Corynebacterium
diphtheriae bacteria type
- nonmotile, noncapsulated, club-shaped
- gram-positive bacillus
causes of diptheria
- person to person through respiratory droplets
- contaminated personal items, household items
- touching contaminated wound
pathogenesis of c. diptheriae
- adheres to mucosal epi cells where the exotoxin (released by endosomes) causes a localized inflammatory rxn then destruction and necrosis
- distruction enables the toxin to be carried lymphatically and hematologically to other parts of the body an can have a systemic effect
incubation period of c. diptheriae
- 2-5 days
- can involve any mucous membrane
types of diptheria
- respiratory: nasal, pharyngeal and tonsillar, laryngeal
- cutaneous
s/sx of diptheria
- thick gray membrane covering your throat and tonsils
- sore throat and hoarseness
- enlarged lymph nodes and bull neck
- difficulty or rapid breathing
- nasal discharge
- fever, chills, malaise
cutaneous diptheria
-type of diphtheria can affect the skin,
causing the typical pain, redness and swelling associated with other bacterial skin infections
-Ulcers covered by a gray membrane also may bdevelop in cutaneous diphtheria
complications of diptheria
- blocking of airway
- myocarditis
- nervous system toxicity
- pneumonia
Dx of diptheria
- pharyngeal gram stain and culture
- wound gram stain and culture
**don’t wait for results to start tx
tx of diptheria
- antitoxin (DAT)
- abs: penicillin or erythromycin
- isolation
- vaccination
- examine close contacts
What is botulism?
-a rare, serious, life-threatening disease -caused by a toxin that attacks the body’s nerves and causes difficulty breathing, muscle paralysis and even death -an intoxication not infection -no person to person spread
bacterium the produces the botulism toxcin
-clostridium botulinum
clostridium botulinum bacteria type
-Anaerobic, gram positive, rod-shaped bacteria
-Spores normally grow in soil or lake sediments
-found on plants growing in feces
contaminated soil
how many forms of botulinum toxins?
- 7
- A-G
which kinds of toxins cause human botulism
- A
- B
- E
- rarely F
50% of food borne botulism outbreaks are from which kinds?
A; then B and E
which kinds of botulism cause illness in birds and mammals?
C, D and E
infant botulism
caused by ingesting spores of the bacteria which germinate and produce toxin in the intestines (honey)
food borne botulism
caused by eating foods that contain botulism toxin
wound botulism
C. botulinum spores germinate in the infected tissue
inhalation botulism
Aerosolized toxin is inhaled:
▪ does not occur naturally and may be indicative of bioterrorism
home canned goods and risk for botulism
-particularly low-acid foods such as asparagus, beets, and corn
honey and risk for botulism
- can contain C. botulinum spores
- not recommended for infants <12 months old
pathogenesis of botulism
-toxin enters blood stream from wound or mucosal surface –> binds to peripheral cholinergic nerve endings –> inhibits release of Ach –> prevents muscles from contracting –> symmetrical, descending, flaccid paralysis from cranial nerve downward
complications of botulism
-Can result from airway obstruction or paralysis of respiratory muscles
-Secondary complications related to prolonged ventilatory support and
intensive care
Sx of botulism
- n/v
- HA
- diplopia
- droopy eyelids
- dysphagia
- dilated/fixed pupils
- extremely dry mouth
- can progress to paralysis and respiratory weakness
infants w/ botulism will present with what sx?
- constipation
- weak cry
- poor feeding
- poor muscle tone
- “floppy baby” syndrome
botulism dx
- toxin bioassay
- sometime EMG
- toxin can be identified by: serum, stool, vomit, gastric aspirate, foods, wound culture
botulism tx
- botulinum antitoxin, heptavalent (HBAT) - > 1yo
- supportive care
- elimination
- abx for wound
- monitor
therapeutic uses of botulism toxin
- focal dystonias
- spasticity
- nondystonic disorders
- strabismus
- disorders of localized muscle spasms
- smooth muscle hyperactive disorders
- cosmetic
- sweating
