Chapter 5: Bacterial Infections Flashcards
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impetigo
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impetigo
what bacteria is impetigo caused by?
streptococcus pyogenes and/or staphylococcus aureus
what are the two forms of impetigo?
nonbullous and bullous
cases of impetigo usually arise in ___ skin
damaged
there is an increase prevalence of impetigo in what 3 populations?
HIV, type 2 DM, and dialysis
which type of impetigo is more prevalent?
nonbullous
nonbullous impetigo most frequently occurs where on the body?
legs
nonbullous impetigo facial lesions are usually located where on the face?
around the nose and mouth
nonbullous impetigo is seen in what age patient mostly?
school-aged children
is impetigo contageous?
yes
in nonbullous impetigo, ___ is common, and itching causes spreading of the infection
pruritis
what is the treatment for nonbullous impetigo?
topical antibiotics
bullous impetigo is seen more commonly in what aged patient?
infants
untreated severe cases of bullous impetigo can lead to what 3 illnesses?
meningitis, pneumonia, and glomerulonephritis
superficial vesicles of bullous impetigo rapidly enlarge to form what?
larger, flaccid bullae, which usually rupture and evelop a thin brown crust (“lacquer”)
what is the treatment of bullous impetigo?
systemic oral antibiotics
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tonsillitis
another name for tonsillitis/pharyngitis is ___
strep throat
what is tonsillitis/pharyngitis caused by?
group A beta-hemolytic streptococci, influenza, and epstein-barr virus
majority is caused by virus
the following are signs/symptoms of what infection?
sore throat, dysphagia, tonsillar hyperplasia, fever, headache, and other constitutional symptoms
tonsillitis and pharyngitis
how is streptococcal pharyngitis and tonsillitis diagnosed?
throat culture
what is the treatment for streptococcal pharyngitis and tonsillitis?
penicillin
what are the four sequelae to streptococcal pharyngitis and tonsillitis?
- scarlet fever
- rheumatic fever
- rheumatic heart disease
- acute glomerulonephritis
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scarlet fever
represents the first two days - white strawberry tongue
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scarlet fever
represents 4-5 days into infection - red strawberry tongue
___ is the result of disseminated group A beta-hemolytic streptococcal infection, with oral features including a white coating on the tongue with only fungiform papilla visible in the first two days, and an erythematous dorsal surface with hyperplastic fungiform papilla during days 4 and 5 of the infection
scarlet fever
first 2 days - white strawberry tongue
days 4-5 - red strawberry tongue
what are the dermatologic features of scarlet fever?
skin erythema (1 week) and desquamation (3-8 weeks)
pastia’s lines - rash in areas of pressure and skin folds presenting as transverse red streaks
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scarlet fever
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pastia’s lines
scarlet fever
what are the 5 possible complications of scarlet fever?
- abscess
- pneumonia
- acute rheumatic fever
- glomerulonephritis
- hepatitis
what is the treatment for scarlet fever?
oral penicillin or erythromycin
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tonsilloliths
tonsillar concretions occur when ___ tonsillar crypts are filled with ___ and ___. secondarily, they become colonized with what bacteria?
- pharyngeal
- desquamated keratin and foreign material
- actinomyces spp.
what is the difference between a tonsillar concretion and tonsillolith?
- when the contents of invaginations become compacted, it’s foul-smelling and termed a tonsillar concretion
- if it undergoes dystrophic calcification, it’s termed a tonsillolith
what are the symptoms of tonsillar concretions/ tonsilloliths?
other than the foul smell of tonsillar concretions, they are asymptomatic
tonsillar concretions and tonsilloliths can promote recurrent ___
tonsillar infections
how are tonsilloliths discovered?
on panoramic radiograph as radio-opaque objects superimposed on the midportion of the mandibular ramus
what are the at home treatments for tonsillar concretions / tonsilloliths?
- gargle warm salt water
- use pulsating jets of water
what are the in-office treatments for tonsillar concretions / tonsilloliths?
- enucleation
- local excision
- tonsillectomy is definitive
what is the bacteria responsible for diphtheria?
cornebacterium diphtheriae
___ are the sole reservoir for diphtheria
humans
what tissues does diphtheria affect first?
mucosal tissues
what are the implications of diphtheria?
lethal exotoxin produced by the bacteria causes tissue necrosis and cardiac complications
syphilis is caused by ___
treponema pallidum
how is syphilis contracted?
primarily through sexual contact and from mother to fetus
syphilis is 6x more common in what populations?
men and african americans
how is primary syphilis characterized?
characterized by the chancre that develops at the site of inoculation (3-90 days after inoculation)
what are the most common sites of inoculation of syphilis?
anus and external genitalia
or lesions account for __% of syphilis inoculation sites. describe the lesions.
- 2%
- most commonly seen on the lip
- primary syphilis is a painless ulceration
another term for secondary syphilis is ___
disseminated syphilis
secondary syphilis occurs ___ weeks after initial infection
4-10 weeks
what are the systemic symptoms of secondary syphilis?
- painless lymphadenopathy
- ALWAYS: diffuse, painless, maculopapular, cutaneous, widespread rash
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diphtheria
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primary syphilis chancres
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primary syphilis chancre
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secondary syphilis
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secondary syphilis
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tertiary syphilis
gumma
after secondary syphilis, patients enter ___ syphilis and are free of ___ for ___ years
- latent
- lesions/symptoms
- 1-30 years
___% of patients will progress from latent syphilis to tertiary syphilis
30%
what are the possible cardiac complications of tertiary syphilis?
- aneurysm of the ascending aorta
- congestive heart failure
- CNS involvement
- paralysis
- psychosis
- death
describe the lesions seen in tertiary syphilis
- ocular lesions
- tongue lesions (syphilitic glossitis)
- intraoral lesions usually affect the palate or tongue
- gumma - characteristic; scattered foci of granulomatous inflammation
what is hutchison’s triad, and what is it associated with?
- hutchison’s incisors
- ocular interstitial keratitis
- 8th nerve deafness
- occurs in congenital syphilis (however, not all people with congenital syphilis will have all of the features of hutchison’s triad)
describe hutchison’s incisors
- greatest mesiodistal width in the middle 1/3 of the crown
- incisal 1/3 tapers to the incisal edge - resembles a flat head screwdriver
- incisal edge has a central hypoplastic notch
what are the dental characteristics of congenital syphilis?
hutchison’s incisors and mulberry molars
what are the ocular characteristics of congenital syphilis?
ocular keratitis, which results in blindness
what bacteria is responsible for gonorrhea?
neisseria gonnorhoeae
___ is the most common reportable infectious disease in the US
gonorrhea
how is gonorrhea contracted?
sexual contact
what are the signs and symptoms of gonorrhea?
purulent discharge and dysuria
what bacteria is responsible for tuberculosis?
mycobacterium tuberculosis
acid fast bacillus
most patients that contract tuberculosis have an ___
immunodeficiency
how does tuberculosis spread?
through airborne droplets
tuberculosis of the skin is called ___
lupus vulgaris
___ is a form of myobacterial infection caused by drinking contaminated milk from an infected cow, and presents as an enlarged cervical lymph node
scrofula
intraorally, how does tuberculosis present?
tongue and palate as a painless, chronic ulceration
describe the histology of tuberculosis
granulomas with central areas of necrosis (caseating granulomatous inflammation)
what is the treatment for tuberculosis?
8-wk course of isoniazid, rifampin, and pyrazinamide, then 16-wk course isoniazid and rifampin
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congenital syphilis
hutchison’s incisors
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congenital syphilis
mulberry molars
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gonorrhea
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tuberculosis
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tuberculosis
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tuberculosis, as indicated by a scrofula
leprosy is a chronic infectious disease produced by what bacteria?
mycobacterium leprae
is leprosy infectious?
it has a low infectivity (exposure rarely results in disease)
82% of all leprosy cases are found in what 5 places? what are the two endemic areas?
- brazil, india, indonesia, myanmar, and nigeria
- endemic areas are louisiana and texas
___ is a host for leprosy
9-banded armadillo
what are the two main categories of leprosy, and what is the significance?
- tuberculoid leprosy (paucibacillary)
- lepromatous leprosy (multibacillary)
- treatment will be different depending on the category
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lepromatous leprosy
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lepromatous leprosy
which type of leprosy is this?
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tuberculoid leprosy
which type of leprosy is this?
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lepromatous leprosy
which type of leprosy is this?
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lepromatous leprosy
describe paucibacillary leprosy
- tuberculoid pattern
- small number of skin lesions
- rare oral lesions
describe multibacillary leprosy
- lepromatous pattern
- loss of hair
- facial skin enlargements = leonine facies
- collapse of bridge of the nose = pathognomonic
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lepromatous leprosy (multibacillary leprosy)
___ is a rapidly progressive, polymicrobial, opportunistic infection that is most frequently preceded by measles
noma
what are the two types of bacteria responsible for noma?
fusobacterium necrophorum and prevotella intermedia
noma frequently begins as ___
NUG
noma most frequently develops in ___ in children of what age?
- africa
- ages 1-7
- nutrition from breastfeeding = carbs and unsafe water
in noma, how do the zones of necrosis present?
- develop in gingiva or soft tissue
- necrosis spreads, but does not follow tissue planes and spreads through anatomic barriers (like muscle)
- necrotic areas are well-defined and unilateral
what is the treatment for noma?
- antibiotics and correct nutrition
- conservative debridement of gross necrotic areas
- aggressive removal is contraindicated (it compounds reconstruction problems - reconstruction is delayed 1 year to ensure complete recovery)
- leave necrotic bone to hold facial form; remove if it sequestrates
what are the mortality rates of noma?
- 95% mortality if untreated
- 10% mortality if treated in the US
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necrotizing ulcerative mucositis, which is characteristic of noma
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noma
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actinomycosis
actinomycosis is a bacterial infection caused by what bacteria?
actinomyces israelii
where can actinomyces israelii colonization occur in healthy patients?
tonsillar crypts, plaque, and/or carious dentin
55% of cases of actinomycosis are diagnosed in the ___ region
cervicofacial
what is the treatment for actinomycosis?
long-term high dose antibiotics
what bacterial infection can result in a suppurative reaction of the infection that may discharge a yellow material? what does the yellow material represent?
- actinomycosis
- represents colonies of bacteria (actinomyces israelii), termed sulfur granules
what bacteria causes cat-scratch disease?
bartonella henselae
cat-scratch disease is the most common cause of ___ in children
chronic regional lymphadenopathy
cat-scratch disease begins in the ___, and classically spreads to ___
- skin
- adjacent lymph nodes
cat-scratch disease arises after contact with what?
- a domestic cat or kitten
- scratches, licks, bites
80% of cat scratch disease cases occur in patients younger than ___
20
what can happen in cases of cat-scratch fever where primary lesions are adjacent to the eye?
can result in a conjunctival granuloma with preauricular lymphadenopathy (= oculoglandular syndrome of parinaud)
how is cat-scratch fever diagnosed?
serologic tests
what is the treatment for cat-scratch fever?
- it is a self-limiting condition
- palliative treatment only unless severely involved, then antibiotics are appropriate
- resolves in 4 months
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cat scratch disease
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cat scratch disease
___ is one of the most common health complaints in the US
sinusitis
sinusitis is usually caused by a blockage of the ___
ostiomeatal complex (therefore disruptive normal drainage)
what are the most common predisposing factors of sinusitis?
- allergic rhinitis
- upper respiratory tract viral infection
if not corrected, acute sinusitis can become ___
- chronic
- defined as recurring episodes of acute sinusitis/symptomatic sinus disease lasting longer than 3 months
in chronic sinusitis, calcification can occur, which is termed a ___
antrolith
describe pain of maxillary sinusitis
- increased pain when head is upright
- decreased pain when patient is supine
- a sinus infection should be strongly considered when patients complain of pain from several teeth
___ helps diagnose chronic sinusitis
radiographic imaging
sinus is cloudy with increased density
what is the treatment for acute sinusitis?
no treatment; disease is self-limiting
what is the treatment of chronic sinusitis?
- if unresponsive, surgical correction to enlarge the ostial openings
- surgery should try to be avoided in children
- decreased distance between orbit and brain
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sinusitis
cloudy right maxillary antrum