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Microbiology 1 > Test 3 (bacteria portion) > Flashcards

Test 3 (bacteria portion) Flashcards

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1
Q

Which disease is caused by R. akari?

A

rickettsialpox

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2
Q

What is the reservoir for rickettsialpox caused by R. akari?

A

mice

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3
Q

What is the vector for rickettsialpox caused by R. akari?

A

mites

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4
Q

Rickettsialpox caused by R. akari is a mild disease with a rash resembling ___________________

A

varcella (chickenpox)

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5
Q

How do you prevent rickettsialpox caused by R. akari?

A

reduce rodent population

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6
Q

Which organism is in the scrub typhus group? What disease does this organism cause?

A

R. tsutsugamushi causes scrub typhus

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7
Q

What are the characteristics of scrub typhus caused by R. tsutsugamushi? How do you prevent this?

A

-resembles epidemic typhus clinically
-bacteria is very toxic and produces an eschar (punched out ulcer covered with a blackened scab) that indicates the mite vector bite

prevention= reduce rodents

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8
Q

Which disease is caused by Coxiella burnetii?

A

Q fever

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9
Q

The genus Coxiella is morphologically similar to __________, but with a variety of genetic and physiological differences

A

Rickettsia

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10
Q

What are the characteristics of C. burnetii?

A

-forms endospore-like structures
-the endospores are resistant to drying and pasteurization
-the spores can survive in dried feces or milk for months

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11
Q

What is the reservoir for Q fever caused by C. burnetii?

A

sheep, goats, and cattle

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12
Q

What is the vector for Q fever caused by C. burnetii? How is it transmitted? Who is most susceptible

A

-no human vector
-it is transmitted to humans by inhalation of dried feces, urine, milk, or placental material from animals like sheep, goats, and cattle
-its usually an occupational hazard for farmers, vets, medical center with large numbers of people exposed to animal shedding the organism
-infections may be acute or mild

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13
Q

Q fever caused by C. burnetii resembles ____________

A

influenza

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14
Q

What is the treatment and prevention for Q fever caused by C. burnetii?

A

-antimicrobial therapy
-high temp short time pasteurization

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15
Q

The chlamydia species is an ___________________ bacteria

A

obligate intracellular

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16
Q

Which bacteria is the smallest and most primitive of cellular organisms?

test q

A

chlamydia species

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17
Q

Which bacteria can synthesize fats, proteins, and carbs, but they are energy dependent parasites that are unable to synthesize their own ATP?

A

chlamydia species

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18
Q

The chlamydia species have a biphasic development (2 phases in life cycle). What are the 2 phases?

test q

A

1) elementary body
-small metabolically inactive
-infectious form
-released by infected host cell

2) reticulate body
-larger non-infectious form
-actively dividing cells
-grows within host cell

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19
Q

What diseases are caused by chlamydia trachomatis (ocular strain, serovars A-C)?

A

ocular infections, trachoma

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20
Q

What diseases are caused by chlamydia trachomatis (serovars D-K)?

A

-STDs
-inclusion conjunctivitis
-infant pneumonitis

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21
Q

What disease is caused by chlamydia trachomatis (serovars L1-L3)?

A

lymphogranuloma venerum (LGV)

note: the name means enlargement of lymph nodes, glands and tissues that are sexually related infections

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22
Q

What disease is caused by chlamydia psittaci?

A

psittacosis/ornithosis (pneumonia)

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23
Q

What disease is caused by chlamydia pneumonia?

A

pneumonia

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24
Q

chlamydia trachomatis (ocular strain, serovars A-C) is an ___________________ bacteria

A

obligate intracellular

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25
Q

What are the characteristics of chlamydia trachomatis (ocular strain, serovars A-C)?

A

-chronic keratoconjunctivitis that begins with acute inflammatory changes in the conjunctiva and cornea and progresses into scarring and blindness
-initial infection occurs in early childhood
-can lead to trachoma
-earliest symptoms are= lacrimation, mucopurulent discharge (pus), conjunctival hyperemia, follicular hypertrophy
-will then see scarring of the conjunctiva, eyelid deformities (entropion, trichiasis) and eyelashes sweeping across the cornea
-may experience secondary bacterial infection which results in loss of vision through the years

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26
Q

How is chlamydia trachomatis (ocular strain, serovars A-C) diagnosed?

A

-becomes purely clinical once symptoms advance
-cytoplasmic inclusions are found in epithelial cells of conjunctival scraping and are stained with fluorescent antibodies or on Giemsa stain

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27
Q

What is the treatment and prevention for chlamydia trachomatis (ocular strain, serovars A-C)?

A

SAFE:
S= surgery for eyelid deformities
A= azithromycin therapy
F= face washing and hygiene
E= environmental improvement (latrines, decreasing the number of flies that feed on conjunctival exudates)

note: this is most prevalent in countries where hygienic conditions are poor and water is scarce

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28
Q

Chlamydia trachomatis (serovars D-K) is an ___________________ bacteria

A

obligate intracellular

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29
Q

Which bacteria causes the most commonly reported STD in the US?

A

chlamydia trachomatis (serovars D-K)

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30
Q

What are the consequences of STDs caused by chlamydia trachomatis (serovars D-K) in women?

A

-up to 40% of women with untreated chlamydia develop pelvic inflammatory disease (PID)
-1/5 women with untreated chlamydia lose the ability to have children
-80% of women with chlamydia have NO symptoms

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31
Q

What are the pathogenicity characteristics of the STI caused by chlamydia trachomatis (serovars D-K)?

A

-most common cause of non-gonococcal urethritis (NGU) in men, but is less severe than gonorrhea
-in women it causes urethritis, cervicitis, and pelvic inflammatory disease (PID) which can lead to sterility and predispose to ectopic pregnancy
-symptoms also include painful urination and increased frequency of urination

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32
Q

What is the most common cause of non-gonococcal urethritis (NGU) in men?

A

STI caused by chlamydia trachomatis (serovars D-K)

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33
Q

What are the pathogenicity characteristics of infant pneumonitis caused by chlamydia trachomatis (serovars D-K)?

A

-infants become infected at birth from infected mother’s birth canal
-causes tachypnea and a paroxysmal staccato cough
-NO fever or eosinophils present
-diagnosis should be suspected if pneumonitis develops in a newborn who has inclusion conjunctivitis
-sometimes these babies also develop otitis media (middle ear) infection with same organism
-note: this is treated the same as pneumonia

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34
Q

What are the pathogenicity characteristics of inclusion conjunctivitis caused by chlamydia trachomatis (serovars D-K)? How are infants and adults different? What are the symptoms?

A

-for babies, it begins as a mucopurelent conjunctivitis 7-12 days after delivery
-adult inclusion conjunctivitis results from sexual contact with a person who has a genital infection
-in adults, it manifests relatively acutely with foreign body sensation, photophobia, often with keratitis (inflammation of the cornea)
-in absence of reinfection, the lesions tend to heal over several months to 2 years

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35
Q

How is inclusion conjunctivitis caused by chlamydia trachomatis (serovars D-K) treated?

A

erythromycin or tetracycline

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36
Q

How are STIs, infant pneumonitis, and inclusion conjunctivitis caused by chlamydia trachomatis (serovars D-K) diagnosed?

A

specimen collection from:
-endocervical
-vaginal
-urethral or
-conjunctival and then put on chlamydiae transport medium

urine may be tested for presence of chlamydial nucleic acid

can do serological testing such as direct fluorescent antibody and ELISA testing

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37
Q

Chlamydia trachomatis (serovars L1-L3) is an _____________ bacteria. It causes lymphogranuloma venereum which is an STD and is more common in males than females

A

obligate intracellular

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38
Q

Chlamydia trachomatis (serovars L1-L3) causes lymphogranuloma venereum, which is an STD. What are the 3 pathogenicity stages and their characteristics?

A

stage 1
-incubation is 1-3 weeks
-rapidly healing, painless genital papule or pustule

stage 2
-painful inguinal lymphadenopathy
-occurs 2-6 weeks after primary lesion

stage 3
-usually years later
-more common in women and MSM (gay men)
-characterized by proctocolitis
-may have rectal fibrosis and stricture in advanced stages (reversible with treatment), and elephantitis of the genitals in men

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39
Q

How is chlamydia trachomatis (serovars L1-L3) which causes lymphogranuloma venereum (STD) diagnosed?

A

frei test (this is a distinct test for LGV)

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40
Q

What is the treatment and prevention for the STD LGV caused by chlamydia trachomatis (serovars L1-L3)?

A

antimicrobial therapy and safe sexual practices

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41
Q

Chlamydia psittaci is an _________________ bacteria that causes psittacosis (also known as parrot fever or ornithosis). It is a human disease acquired from contact with birds (usually exotic birds). It produces a spectrum of clinical manifestations ranging from….

A

obligate intracellular, severe pneumonia and sepsis to mild asymptomatic infection

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42
Q

What are the pathogenicity characteristics of psittacosis (also known as parrot fever or ornithosis) caused by chlamydia psittaci?

A

-bacteria enters through the respiratory tract from inhalation of dried bird feces and infects lung tissues
-found in the blood during the first 2 weeks of the disease and may be found in the sputum as well
-will experience sudden onset of influenza like symptoms
-incubation period is approx 10 days
-symptoms= malaise, fever, anorexia, sore throat, photophobia, and severe headache
-several cases will have bronchial pneumonia at the end of the first week
-mortality rate is 20% if left untreated

43
Q

How is psittacosis (also known as parrot fever or ornithosis) caused by chlamydia psittaci diagnosed?

A

-clinical diagnosis, rather than labs usually
-immunoassay or PCR is preferred
-serological testing

44
Q

What is the treatment and prevention for psittacosis (also known as parrot fever or ornithosis) caused by chlamydia psittaci?

A

treatment= antimicrobial therapy

prevention=
-outbreaks may occur whenever there is close contact between humans and infected birds
-so, control bird shipments
-quarantine
-test imported birds for infections and treat with tetracycline in bird food

45
Q

What bacterial species/bacteria are spirochetes?

A

1) treponema sp.
2) borrelia sp.
3) leptospira interogans

46
Q

What is the 1 venereal treponematoses?

A

Treponema palidum

47
Q

What disease is caused by Treponema pallidum?

test q

A

syphilis

48
Q

What are the microbio characteristics of Treponema pallidum?

A

-slender spirals/ spiral coils regularly spaced (bc its a spriochete bacteria)
-actively motile

49
Q

How is syphilis caused by Treponema pallidum transmitted?

A

-humans are the only host
-bacteria enters through mucus membrane

50
Q

What is primary syphilis?

test q

A

-caused by Treponema pallidum
-incubation is usually 3 weeks
-pt will have a chancre lesion, which is a painless circular purplish ulcer with a small raised margin with hard edges (its like a canker ulcer)
-the lesion develops at the site of entry of the spirochete
-organism is present on the lesion

51
Q

Is primary syphilis treatable?

test q

A

YES

52
Q

What is secondary syphilis?

test q

A

-caused by Treponema pallidum
-primary syphilis has a chancre lesion
-secondary syphilis is where the lesion has already healed
-will have fever and flu like symptoms, and swollen lymph nodes
-becomes a systemic infection now
-will have skin rash that may be mistaken for measles, rubella, or chicken pox (Great Imitator)
-the rash appears as reddish brown spots on the palms, soles, faces, and scalp
-organism is present on the lesion
-symptoms will eventually subside and pt will enter latent period for several years

53
Q

Is secondary syphilis treatable?

test q

A

yes

54
Q

What is tertiary syphilis?

test q

A

-caused by Treponema pallidum
-this occurs in only 40% of patients who left primary and secondary syphilis untreated
-usually occurs many years after secondary syphilis
-may appear on the skin, skeletal system, cardiovascular system, or in nervous system
-organism cannot be found, its like a mystery
-the hallmark sign is gumma, which is a soft painless noninfectious granular lesion
-the lesion may weaken major blood vessels and cause them to burst
-if the lesion is in the spinal cord or on the meninges then it can lead to degradation of tissues and paralysis
-if the lesion is in the brain, then it can alter the patients personality and judgment skills
-may need to be hospitalized at mental institutions

55
Q

Is tertiary syphilis treatable?

test q

A

NO

56
Q

What is the hallmark sign of tertiary syphilis?

test q

A

gumma lesion (soft, painless, gummy noninfectious granular lesion)

57
Q

What is congenital syphilis (ToRCHeS infections, S is for syphilis)?

A

spirochetes penetrate the placental barrier after the 3rd or 4th month of pregnancy and causes congenital syphilis (causes damage to fetus and can result in birth defects)

58
Q

How is syphilis caused by Treponema pallidum diagnosed?

A

-nontreponemal tests used as screening tests
-treponemal antibody tests
-specimens from tissue fluid from early surface lesions of spirochetes by either dark-field or immunofluorescence microscopes, or nucleic acid amplification
-blood for serologic testing
-CSF for neurosyphilis testing

if you can only memorize one thing, then memorize the dark field microscopes

59
Q

What is the treatment for syphilis caused by Treponema pallidum?

test q

A

penicillin

60
Q

What are the 3 non-venereal treponematoses (endemic syphilis) bacterias?

A

1) treponema pallidum endemicum causes bejel
2) treponema pallidum pertenue causes yaws
3) treponema pallidum carateum causes pinta

61
Q

What disease is caused by treponema pallidum endemicum?

A

bejel

62
Q

What shape is treponema pallidum endemicum?

A

-slender spirals
-spiral coils are regularly spaced

63
Q

Which age group is bejel caused by treponema pallidum endemicum common in?

A

children

64
Q

What is bejel caused by treponema pallidum endemicum?

A

-highly infectious/contagious skin lesions that are transmitted by direct contact
-after latent period, may develop bony and cartilaginous involvement and chronic skin ulcerations

65
Q

What is the treatment for bejel caused by treponema pallidum endemicum?

A

penicillin

66
Q

What disease is caused by treponema pallidum pertenue?

A

yaws

67
Q

What disease is commonly misdiagnosed? Why?

A

yaws caused by treponema pallidum pertenue

bc the facial deformities and tissue build up looks like cancer or leprosy

68
Q

What shape is treponema pallidum pertenue?

A

-splender spirals
-spiral coils are regularly spaced

69
Q

Where is treponema pallidum pertenue most commonly found?

A

-endemic in hot humid tropics like Africa near the equator
-poor communities
-poor socio-economic conditions with lack of hygiene and overcrowding

70
Q

What is yaws caused by treponema pallidum pertenue? How is it transmitted?

A

-its a primary lesion that looks like an ulcerating papule, found on arms or legs
-without treatment, the infection can spread and lead to chronic disfigurement and disability in tissues like the face
-transmission is person to person
-most people affected are 15 y/o and younger

71
Q

How is yaws caused by treponema pallidum pertenue treated?

A

azithromycin or benzathine penicillin

72
Q

What disease is caused by treponma pallidum carateum?

A

pinta

73
Q

What shape is treponma pallidum carateum?

A

-slender spirals
-spiral coils are regularly spaced

74
Q

How is pinta caused by treponma pallidum carateum transmitted?

A

direct contact of flies or gnats

75
Q

What is pinta caused by treponma pallidum carateum?

A

-skin disease
-the lesions are only on the dermis
-the lesions will begin at the site as a small papule but then enlarge and become hyperkeratotic
-lesions are mainly on extremities, face, or neck
-after 3-9 months, further thickened and flat lesions appear all over body and at bony prominences
-some lesions will eventually look like slate blue color or depigmented (can cause hyperpigmentation or hypo-pigmentation of skin)

76
Q

How is pinta caused by treponma pallidum carateum treated?

A

penicillin or azithromycin

77
Q

Prevotella melaninogenicus (gram neg anaerobic bacteria) WITH fusobacterium sp. (gram neg anaerboic bacteria) WITH TREPONEMA VINCENTII causes what disease?

test q

A

acute necrotizing ulcerative gingivitis (trench mouth)

78
Q

What is acute necrotizing ulcerative gingivitis (trench mouth)?

A

-severe form of gingivitis that causes painful infected bleeding gums and ulcers
-causes stinky breathe bc of dying tissue
-this disease is rare in developed countries since we have good hygiene
-the poor hygiene allows large ulcers to form and multiply in the gums
-will be extremely painful and cause bad taste in mouth

79
Q

What are the risks for getting acute necrotizing ulcerative gingivitis (trench mouth)?

A

-living in developing country
-poor nutrition or hygiene, and poor living conditions

80
Q

How is acute necrotizing ulcerative gingivitis (trench mouth) treated?

A

-antibiotics
-antiseptic mouthwash
-painkillers

81
Q

How is acute necrotizing ulcerative gingivitis (trench mouth) diagnosed and prevented?

A

diagnosis= clinical

prevention= teeth/mouth hygiene practices

82
Q

What disease is caused by borrelia recurrentis?

A

epidemic relapsing fever

83
Q

What is the largest pathogenic spirochete bacteria?

test q

A

borrelia recurrentis

84
Q

What is the vector for epidemic relapsing fever caused by borrelia recurrentis?

A

louse

85
Q

What is epidemic relapsing fever caused by borrelia recurrentis?

A

-larger scale and longer duration than endemic relapsing fever caused by borrelia hermsii and borrelia turicatae
-causes fever, shaking, chills, headache, prostration and drenching sweats
-the symptoms last a few days and then disappear AND then REAPPEAR up to 5x in the next several weeks
-spirochetes change their surface antigen during growth, and so by the time initial Ab is formed, it becomes useless bc theres a new surface Ag and this can happen multiple times

86
Q

What is the treatment and prevention for epidemic relapsing fever caused by borrelia recurrentis?

A

tx= antibiotics

prevention= lice control

87
Q

What disease is caused by borrelia hermsii and borrelia turicatae?

A

endemic relapsing fever

88
Q

Borrelia hermsii and borrelia turicatae are a spirochete bacteria. What is the vector and reservoir?

A

vector= tick

reservoir= rodents

89
Q

What is endemic relapsing fever caused by borrelia hermsii and borrelia turicatae?

A

-causes fever, shaking, chills, headache, prostration and drenching sweats
-has very similar clinical manifestations to epidemic relapsing fever caused by borrelia recurrentis BUT its a much shorter duration and affects less people

90
Q

What is the treatment and prevention for endemic relapsing fever caused by borrelia hermsii and borrelia turicatae?

A

tx= antibiotics

prevention= tick control

91
Q

What disease is caused by borrelia burgdorferi?

A

lyme disease

92
Q

What is the vector for lyme disease caused by borrelia burgdorferi?

A

small ixodes tick

93
Q

What is the reservoir for lyme disease caused by borrelia burgdorferi?

A

white footed mouse

94
Q

What is the most commonly reported arthropod borne illness in the US currently?

A

lyme disease caused by borrelia burgdorferi

95
Q

Can you die from lyme disease caused by borrelia burgdorferi?

A

yes, but its not very common

you body can have substantial damage though

96
Q

What are the pathogenicity characteristics of lyme disease caused by borrelia burgdorferi? What are the 3 stages of the disease?

A

-after attaching to the host, the tick takes a blood meal and defecates into the wound, and if the tick is infected then spirochetes will be transmitted
-the incubation period is 3-31 days

3 stages:
1) early localized stage
-slowly expanding red rash at site of tick bite is called erythema (red) migrans
-will have a flat or raised lesion and the rash will increase in diameter in a circular pattern over weeks
-sometimes diameter can be as long as 10-15 in!
-the lesion will have an intense red border and central clearing, termed as the “bull’s eye rash” (looks like target sign)
-other symptoms include: fever, headaches, and pain

2) early disseminated stage
-becomes systemic, can take months to years after first stage
-skin will have multiple smaller erythema migrans develop
-if it spreads to NS, then pt can get meningitis, facial palsy, and peripheral nerve disorders
-cardiac abnormalities are the most common and the symptom for it is brief irregular heartbeats
-joint and muscle pain can also occur

3) late stage
-can happen months or years after stage 2 if left untreated
-about 10% of patients develop chronic arthritis with swelling in the large joints such as the knee

97
Q

How is lyme disease caused by borrelia burgdorferi diagnosed?

A

-rash observation (clinical)
-DNA and PCR testing
-ELISA and indirect fluorescent antibody assays (IFA) are most widely used
-immunoblot is generally used to confirm results obtained from ELISA

98
Q

What meds are used for treatment of lyme disease caused by borrelia burgdorferi?

test q

A

early infection w/
-doxycycline
-amoxicillin
-cefuroxine axetil for 14-21 days

arthritis
-doxycycline
-amoxicillin
-penicillin G
-ceftriaxone

99
Q

What disease is caused by Leptospira interrogans?

A

leptospirosis (weil’s disease)

100
Q

Which bacteria is a thin, coiled spirochete usually with a hook at one end resembling a question mark?

A

Leptospira interrogans

101
Q

What is the most widely spread zoonosis?

A

Leptospira interrogans

102
Q

How is Leptospira interrogans spread causing leptospirosis (weil’s disease)?

A

-spirochetes colonize the kidney tubules in infected animals (cats, dogs, farm animals, etc)
-humans acquire it by contact with infected animals or soil, food, or water contaminated with infected animal urine

103
Q

What are the pathogenicity characteristics of leptospirosis (weil’s disease) caused by Leptospira interrogans? What are the 2 stages?

A

-swimming or wading in contaminated water, the bacteria enters through mucus membranes of the eyes, nose, mouth, and skin, especially if theres any cuts of wounds already
-bacteria multiplies rapidly and pt will have flu-like symptoms and for only 5-10% of patients it will become systemic and lethal

early phase
-headache, muscle aches, vomiting, nausea, conjunctivitis
-episodes of high fever and chills

late phase
-fever returns after a week or two
-meningitis is common in this stage
-inflammation in lungs and liver can occur
-kidney damage and jaundice is most common at this stage
-can vomit blood, have gastric hemorrhages with liver and kidney dysfunction

Microbiology 1 (5 decks)

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