6 abscesses Flashcards
abscess
a swollen, inflamed area in body tissues, in which pus gathers and would presumably drain from
what determines the pathogens within the abscess
flora of the region
what determines the site of the abscess?
- head and neck anatomy
- syndromes you must recognize
- therapeutic principles/guidelines
how can organisms involved in abscesses reach a normally sterile internal area?
blood borne
penetration/trauma
extension from a nearby non-sterile area, such as a mucosal surface
blood borne
hematogenous spread
penetration/trauma
knife wound
extension from a nearby non-sterile area such as a
mucosal surface
most brain abscesses are from
oral focus
eusobacterium
oral flora that can spread to brain tissue
commensal
normal flora
streptococcus pyogenes
group A strep
what adheres well to oral epithelial cells and
strep pyogenes (group A strep)
S salivarius and veillonella species colonize
tongue + buccal mucosa
S mutans + mitis and actinomyces viscosus colonize
dental surfaces
staphylococcus aureus is present on
skin and nares
pelvic abscess is an extension of an
intestinal wall infection (diverticulitis) + contains a mixture of bacteria that originated in the large intestine
abdominal abscesses
aeropic organisms + anaerobes
aerobic organisms of abdominal abscesses
e. coli which tolerate anoxic conditions
anaerobes of abdominal abscesses such as bacteroides
not killed by tiny doses of oxygen, and have enzymes such as superoxide dismutase to detoxify oxygen radicals and catalase to break down hydrogen peroxide
anaerobes
clostridia, anaerobic and facultative anaerope, strep
strict anaerobe
facultative anaerobe
2-8% oxygen
abscesses in gluteus muscle
cardiac infection (endocarditis) allowed bacteria to spread to the butt via the bloodstream
what causes cardiact valve infections?
staphylococcus + streptococcus
distant site abscess is a pure culture of the
single organism
hematogenous spread= bacteremia common with
skin infections, pneumonia, uti/kidney infections
secondary sites of hematogenous spread
large joints (hips, elbows), bones, lungs, liver, spleen`
bacteriology of the abscess may be anticipated from
the microbial flora of the originating focus
most abscesses originate from
teeth, dental crevices
most abscesses harbor
harbor four or five organisms, mainly oral anaerobes
infections arise from the pharynx contain oral anaerobes and
strep pyogenes + staph aureus
polymicrobial synergy
typical deep neck ifnections + abscesses include on average 5 or 6 bacterial species
-synergy between a # of species renders the whole pathogenic
upper airway harbors large numbers of what kind of bacteria?
anaerobic bacteria of limited virulence unless allowed entry into sterile areas
some pathogens need no assistance! no polymicrobial synergy
staph + strep fusobacterium
how do polymicrobibal synergistic infection species work?
add something necessary but not sufficient
pyrosequencing
many uncultured species
example of pyrosequencing
bacteroids fragilis has a capsular polysaccharide complex (CPD) with (+) and (-) charges promoting abscesses; without CPD, no abscess is formed
with polymicrobial synergistic infections, tx has to be aimed at
different kinds of bacteria, not just one
abcesses can be
polymicrobial
how are organisms introduced during abscess formation
trauma or via bloodstream (local)
what can narrow the mixture of organisms?
early presence of oxygen and then later, the lack of oxygen
host response to abscess
walls off organisms with fibrin deposition, eventually thick-walled fibrous collagen capsule
inside an abscess
live/dead cells, bacteria, debris
healthy tissue is well oxygenated unless you have
- interruption of blood flow (surgery + trauma)
- ischemic necrosis from tumors
- adjacent infection
adjacent infections produce
cytotoxic and necrotizing factors extending infection; organisms can consume oxygen rednering tissue anaerobic, which means dead tissue
are most oral infections anaerobic or aerobic?
anaerobic (oral abscesses, periodiontal lesions, pulp, periapical lesions0
oxygen tolerance varies from species to species
-requires low [02] and reduced oxidation-reduction potential
anaerobes outnumber aerobes by how much in the oral cavity and skin
10:1
anaerobes outnumber aerobes by how much in the colon
1,000 : 1
few anaerobes by themselves are very virulen
fusobacterium, clostridium, + bacteroides
what presents on gram negs, and have a strong correlation with pulp + periodontal damage and endotoxin?
endotoxin; metabolites (hydrogen sulfide, ammonia) and injurious enzymes are made
host neutrophils require oxygen for their
metabolic burst but is lacking
beta- lactamases mediate
penicillin resistance
bacteria have acquired antibiotic resistance like
beta lactamase + penicilin lactamase
anaerobic infections characteristics
- polymicrobial, usually endogenous + opportunistic
- occur in closed spaces
- smell foul (cadavers)
- accompanied by thrombophlebitis
thrombophlebitis
bacterial enzymes promote clot formation; gram neg endotoxins activate clotting cascade, bad since clotted vessels lead to death
why are abscesses often biphasic
phase 1 acute inflammation phase 2 local abscess formation
resurgent infection
some anaerobes (bacteroides) are resistant to antibiotics, so initial tx with antibiotics may kill off bacteria, but not the bacteroides, leading to resurgent infection
resurgent infection
kils of bacteria that are sensitive to antibiotics, but the ones that aren’t still survive, so youthink people are fine, but they are in fact still sick
cervical fascia
muscles, vessels, and visceral structure of the neck are eveloped in fascia
interfascial spaces
potential areas where abscesses can sit
what are borders for infections
fascia
pediatric neck abscessse commonly in
submandibular and posterior triangle and submental
superficial fascia
subcutaneous tissues of neck which are continuous with platysma anteriorly; begins at nuchal line
what does the superficial fascia enclose
trapezius SCM strap mmms submaxillary glands parotid glands
middle or pretracheal fascia
often involved in dental infections that have extended from site of origin
infection in what artery with compromise blood flow to brain
carotid
second spaces
within submental + submandibular triangles, between mucosa of floor of mouth and superficial layer of deep fascia
what divides the second spaces
myelohyoid mucsle into submandibular + sublingual spaces
clinical syndromes
- peritonisillar, parotid, parapharyngeal and submandibular abscesses
- parapharyngeal space abscess
- pterygopalatine, infratemporal, + temporal fossa abscesses
- retropharyngeal abscesses
- lung abscesses
*sore throat and trismus is sean in
peritonsillar , parotid, parapahryngeal, and submandibular abscesses
trismus
inability to open the jaw; pressure or infection of the muscles of mastication
trismus involves motor branch of which nerve
trigeminal
dysphagia (can’t eat) + odynophagia (can’t swallow
inflammation of cricoarytenoid joint
dysphonia + hoarseness
- neck infection (10th cranial nerve)
- unilateral tongue paresis (12th cranial nerve
stridor + dypsnea
local pressure or spread of infection to mediastinum
unilateral tongue paresis
nerve problems
patients w/ peritonsillar, parotid, parapharyngeal, and submandibular abscesses have
- facial + neck swelling, erythema, purulent oral discharge
- pooling of saliva in mouth and asymmetry of oropharynx to help determine where problem is\
- adenopathy
- flucuation
adenopathy
enlargement of lymph nodes anywhere in body
characteristic signs of deep pus
pitting or a doughy feeling on firm deep palpation
Is ludwig’s angina an abscess?
no, but can be consued with on
ludwig’s angina
rapidly spreading cellulitis, not an abscess
what anatomical feature does ludwig’s angina include
floor of the mouth and loose areolar tissue above the myelohyoid diaphragm
what are the dominant flora in ludwig’s angina
oral flora = strep and anaerobes
what precedes ludwig’s angina in a most cases
recent lower molar extraction
what is critical to control during ludwig’s angina
airway control, asphyxiation is a route of death, as is sepsis
why does ludwig’s angina look like an abcess?
fluids and gases collect and can mimic collection of pus
what is commonly seen with ludwig’s angina
people with bad oral hygiene and trismus
tx ludwig’s angina
antibiotic therapy
how does death occur during ludwig’s angina
suffocation (edema mouth, togue, glottis) mediastinitis, septicemia, pneumonia
ludwig’s angina II
brawny or indurated edema of the neck, hard, does not give, no pus formation
indurated
hardened
who does acute bacterial parotitis usually affect
elderly, dehydrated, intubated, postoperative individual
acute bacterial parotitis
salivary stasis permis retrograde seeding of stensen’s duct with virulen oral flora
risk factors for acute bacterial parotitis
recent vigorous teeth cleaning, use of antcholinergic drugs and salivary calculi
most common pathogen in acute bacterial parotitis
staphyloccoccus aureus but anaerobes, enteric gram neg bacterial and other organisms also seen
acute bacterial parotitis patients present with
pain, swelling of parotid gland and dysphagia
acute bacterial parotitis and stensen’s duct
pus can be expressed, it should be cultured and gram stained
-gland can suppurate and abscess may be present
treatment for acute bacterial parotitis
hydration, antibiotics directly against staphlococci + mouth flora
stone forms in stensen duct of acute bacterial parotitis
person is dehydrated, difficulty forign saliva, taking meds
give lemon drops to patients with acute bacterial parotitis
to stimulate salivary production
acute bacterial parotitis usually caused by
staph!
true submental + submandibular abscesses
usually after an infected submandibular lymph node or salivary gland suppurates
true submental + submandibular abscesses fluctuation is easy becasue
no overylying musculature and fascia is not dense
submental abcesses usually ressult from
spread of an apical abscess of the lower incisors through the thin buccolabial acrolar plate and below the myelohyoid diaphragm or from suppuration of a submental lymph node
true submental + submandibular abscesses
elevation of floor of mouth may be seen but swelling of ludwig’s angina is NOT PRESENT
true submental + submandibular abscesses infection can be so bad that it destroys the
lymph node or salivary gland leading to an abscess
parapharyngeal
lateral pharyngeal= pharygomaxillary space
parapharyngeal space
upper neck, above the hyoid; inverted cone with base bounded by the skull and apex toward the hyoid bone
parapharyngeal space close to the
carotid sheath
6 lymph nodes
form a collar around the junction of head and neck; rest are chains
6 lymph node groups
occipital mastoid parotid facial submandibular submental
node chains
lateral and anterior cervical nodes
common root for drainage of nodes
lateral cervical chain
final conduit form from all lymphatics in the head and neck
large deep carotid sheath chain
before antibiotics, half of all head and neck infections were from
infection in tonsils or pharynx
what usually arises as a complication of peritonsillar abscess but infections of the parotid gland, dental roots, petrous pyramid, or after dental or pharyngeal surgery may extend into this space
parapharyngeal abscess
triad of pharyngeal abscess
tonsillar prolapse with swelling of lateral pharyngeal wall, trismus, and parotid swelling
abscess in parapharyngeal space
extension of abscess into the carotid sheath is frequent
**erosion of the internal carotid artery leads to s
strokes, fatal hemorrhage, thrombophlebitis of the internal jugular vein with intracranial extension
inferior extension to the pyriform sinus during parapharyngeal space abscess leads
obstruction of upper airway
extension from the retropharyngeal space or carotid sheath during parapharyngeal space abscess leads to
mediastinitis
septic thrombosis
blood flow through carotid only on one side so one side of the brain has no blood flow
pterygopalatine fossa
maxillary nerve + branches, sphenopalatine ganglion, internal maxillary artery and branches
infections of maxillary and spenoid sinuses can involve
abducens nerve, inferior branch of the oculomotor nerve, and maxillary nerves
where do infections after a extraction of a maxillary molar tooth or after local anesthesia of the superior alveolar nerve cause infections?
pterygopalatine, infratemporal, and temporal fossa infections
fulminant cellulitis
involves upper molar gingiva, pterygopalatine, infratemporal, and temporal fossa, and then abscess formation in these spaces ensues
proptosis of the ye bc pus in inferior orbit requires (pterygopalatine abscess)
surgical drainage
what is the most important communication between the neck and the chest
retropharyngeal space
retropharyngeal space
runs longitudinally from the base of the skull to the posterior mediastinum-between the prevertebral fascia posteriorly and the posterior aspect of the pretracheal fascia anteriorly
what does the retropharyngeal space communicate with?
parapharyngeal space laterally, where it is bounded by carotid sheaths
retropharyngeal abscess
results from lymphatic spread of infection in the pharynx or sinuses to the retropharyngeal lymph nodes . The nodes suppurate, leading to abscess
retropharyngeal lymph node abcesses are common in
children age 3 or 4 bc that’s when these lymph nodes involute
in older children or adults, abscess can occur after
accidental perforatoin such as with a fish bone or lollipop stick
retropharyngeal abscesses are polymicrobial
with anaerobes, streptococci, and staphylococcci predominating
retropharyngeal abscess symptoms
- chillls and fever after pharyngitis
- dysphagia
- neck pain
- dypnea
- regurgitation
children with retropharyngeal abscess may have
insidious onset with irritablility + refusal to eat
neck during retropharyngeal abscess
hyperextended with local tenderness
retropharyngeal symptoms
muffled voice (Dysphonia) + drooling followed by tachypnea + stridor
what is the most important tool for diagnosis of retropharyngeal abscess
lateral neck radiograph
what are treatments of retropharyngeal abscess
drainage and high dose penicillin or clindamycin
thickened pre-vertebral fascial space
extra space between arrow and vertebral column- entire airway is pushed forward
rupture of the abscess can lead to
aspiration of the pus into the lungs, and pneumonia and empyemia
an abscess in the danger space between the alar and the prevertebral fascias may drain into the mediastinum , resulting in
mediastinitis
hemorrhage suggest
involvement of the major blood vessels, and phlebitis or thrombosis of the internal jugular vein
lung abscesses
aspiration of oral contents, anaerobic flora predominates, alcoholics, people who have been in the hospital, little gastric acid may have different flora
lung abscesses
staphlococcus aureus, gram negative enterics often colonize the mouth and upper intestinal tract in those who belong to the latter group. thus, anaerobes, and at times S. aureus and gram negatives, are found in lung, again polymicrobial
lung abscesses description
- inoculum size must be big enough
- acid may induce a chemical pneumonitis
- occlusion of the airway by food or foreign objects renders the area anaerobic
- synergism of diff bacteria
- nutritional state and integrity of the host defenses are important
- aspiration pneumonia now very common
initially, lung abscesses begin with
a necrotizing pneumonia, often after aspiration
lung abscesses- microabscesses
form and coalesce
2 weeks after aspiration
lung abscess is seen
location of lung abscesses depends on the dependent region
lower lobes more comon than upper
=people who have gotten drunk and passed out upside down before aspiration or inhalation of vomitus may be in upper lobes
lung abscess drains into
bronchiole, causing foul sputum and foul oral odors
if air gets into lung abscess cavity
then an air-fluid lvel may be seen on chest radiograph
if a lung abscess drains into the pleura,
an empyema may form
lung abscess tx
drain, long course of antibiotics-can be oral after iv
bubbles in radiographs are probably
abscesses
therapy of abscesses
- activity against anaerobes or aerobes
- bacteroides make beta lactamase limiting penicillin, therefore broad spectrium penicillins (beta lactam) + beta lactamase inhibitor are useful like ampicillin/sulbactam
what is also used as therapy for abscesses
metronidazole, clindamycin btu bacteroides are becoming resistant to clinda
clindamycin fights
strep, staph, anaerobes
1st main cause of sore throat
strep
2nd main cause of sore throat
gonorrhea
