Exam 3: Miscellaneous Bacterial Agents of Disease Flashcards
1
Q
comma-shaped rods, single polar flagellum, gram negative
A
vibrio species lab id
2
Q
vibrio cholerae possess unique
A
O & H antigens
3
Q
cholera is caused by
A
toxigenic strains of V. cholerae (O1 and O139 serotypes)
4
Q
how does someone get vibrio cholerae?
A
ingested via contaminated food or water
5
Q
where does vibrio cholerae infect?
A
surface of small intestine
6
Q
t/f vibrio cholerae is invasive?
A
false
7
Q
incubation period of vibrio cholerae
A
2 hours to 5 days
8
Q
VF of vibrio cholerae
A
cholera toxin
9
Q
cholera toxin causes
A
electrolyte and water loss through dramatic, high, volume, secretory diarrhea RICE WATER STOOLS
10
Q
rice water stools is associated with which pathogen
A
vibrio cholerae
11
Q
`Pt from Haiti presents with severe, watery diarrhe with mild to severe dehydration due to toxin production, you’re worried because death can occur within 48 hours, what pathogen infected this pt?
A
vibrio cholerae
12
Q
Causes cells to pump out large amounts of cl and bicarbonate so positively charged Na and K go out which then causes water to follow leading to dehydration
A
vibrio cholerae
13
Q
causes gastroenteritis via its 2 enterotoxins from RAW SEAFOOD, SHRIMP, TUNA, SQUID, CRAB
A
vibrio parahaemolyticus
14
Q
t/f vibrio parahaemolyticus is self limited
A
true–usually resolves itself within 3 days
15
Q
pt presents with explosive, watery diarrhea, abdominal pain, fever
A
vibrio parahaemolyticus
16
Q
gastroenteritis usually from RAW OYSTERS; can lead to bacteremia and sepsis esp. in IC and diabetics
A
vibrio vulnificus
17
Q
causes RAPIDLY PROGRESSIVE WOUND INFECTIONS eg. cellulitis in the setting of contaminated salt water and carry a HIGH MORTALITY RATE if not treated early
A
Vibrio vulnificus
18
Q
3 bacteria pathogens found within saltwarer
A
Vibrio cholerae, vibrio parahaemolyticus, vibrio vulnificus
19
Q
how is the vibrio species diseases transmitted?
A
either by consumption or contamininated shellfish or traumatic injury associated with infected water
20
Q
heat-labile enterotoxin CJT causes most of the symptoms
A
VF of campylobacter jejuni
21
Q
curviform bacteria, short spirals or curved rods; one flagellum
A
campylobacter jejuni lab id
22
Q
import cause of bacterial gastroenteritis in DEVELOPED COUNTRIES; ingested via CHICKEN, milk, water, other meats
A
campylobacter jejuni
23
Q
incubation period of campylobacter jejuni
A
1-7 days
24
Q
reaches mucosa at the ileum near colon; adheres & invades leading to inflammation, abscesses, & occasionally bacteremia
A
campylobacter jejuni
25
Sx: HA, fever, abdominal pain, secretory diarrhea; MAY MIMIC APPENDICITIS
campylobacter jejuni
26
pt presents will appendicitis like pain but on CT is shows inflammation of the colon rather than acute inflammation of the appendix...what pathogen infected this pt?
campylobacter jejuni
27
how long does campylobacter jejuni usually last
typically 3-5 days but can last up to 2 weeks
28
VF of helicobacter pylori
able to inhabit the human stomach, UREASE allows it to live in low pH due to generation of ammonia
29
lab id of helicobacter pylori
curviform bacteria; curved rods with severeal polar flagella
30
causes stomach and duodenal ulcers (90%)
helicobacter pylori
31
how is h. pylori spread?
person to person via fecal-oral route
32
dx or h. pylori
direct: biopsy, indirect: urea breath test or stool antigen test
33
tx of h. pylori
triple therapy! PPI + amoxicillin + clarithromycin
34
lab id of treponema pallidum
weakly gram negative --> need special stains; darkfield microscopy, immunofluorescence
thin, regular, coiled cells
35
strict parasites that can only be cultured in live cells
treponema pallidum
36
what is the sole natural host of treponema palldium?
humans
37
where on humans does treponema pallidum like to live?
genital region and oral cavity
38
t/f treponema pallidum is extremely fastidious and sensitive; it cannot survive long outside of the host
true
39
how is syphilis (treponema pallidum) transmitted
contact with lesions or via placenta
40
wherever the spirochete (treponema pallidum) lands is where
lesion will occur
41
Pt is contagious
first stage of infection, localeized, PAINLESS chancre (progresses from erythemic macule to papule to ulcer); serologic tests may not be positive during early in this stage (bc body takes a few weeks to make antibodies)
primary syphilis
42
what causes syphilis?
treponema pallidum
43
Contagious; weeks to few months later, 25% of untreated patients will develop a systemic illness that presents with GENERALIZED, DIFFUSE MACULOPAPULAR RASH --> affecting the palms and sole, does not hurt or itch, can persist for months; may also present with conylomata lata; serologic tests are usually highest in titer during this stage
secondary stage of syphilis
44
look similar to genital warts but are smoother, typically have a flat top to them, usually skin color or redish brown
condylomata lata
45
condylomata lata are associated with which stage of syphilis?
secondary
46
host suppresses infection, but spirochete is still present --> no lesions are clinically apparent; asymptomatic
only evidence is positive serologic test
can occur between primary and secondary stages or after secondary stages
latent stage of syphilis
47
which stage of syphilis is the patient usually not contagious during?
tertiary
48
occurs months to years later untreated patients can develop neurologic symptoms and gumma
tertiary syphilis
49
granulomatous lesions that destroy soft tissue, cartilage, and bone; can occur in skeletal, spinal, and mucosal areas; the eyes, and viscera (lung, stomach, liver, genitals, breast, brain, and heart)
gummas
50
results from damage by the spirochete, presents as ascending aortic aneurysm, aortic valve insufficiency and/or heart failure
cardiovascular syphilis
51
usually occurs during the tertiary stage but literature say it can occur at any stage; occurs when the bacteria invades the CNS; spirochetes destroy the blood vessels in the brian, cranial nerves, and dorsal roots of the spinal cord
neurosyphilis
52
via placenta
most common manifestationsa re recgonzied at 2 years of age
bone and tooth deformities (hutchinson's teeth), deafness, nervous system abnormalities; may lead to stillbirth, neonatal death, infant disorders; transmission can occur during any stage of syphilis but risk if much higher during primary and secondary stages
congenital syphilis
53
what happens if syphilis is not treated
it will become chronic
54
tx for syphilis
penicillin
55
populations at increased risk for syphilis
men who have sex with men, men who have sex with both men and women, african american/black population
56
T. pallidum enters body via
abraded skin and mucous membranes during sexual contact --> binds to mucous membranes or dmaged skin using its hooked endoflagellum
57
incubation period of t. pallidum
3 weeks -- asymptomatic
58
dx of early syphilis
clinical presentation + id of tremponema pallidum in lesion exudate or tissue (antibodies might not be present yet)
59
dx or secondary, latent, and tertiary syphilis
serology (nontreponemal and treponemal)
60
measure ANTIBODY DIRECTED AGAINST A CARDIOLIPIN ANTIGEN; not specific
nontreponemal test
61
VDRL and RPR are examples of
notreponemal tests
62
nontreponemal tests are considered
screening tests, but are used to follow treatment responses as well
63
results from nontreponemal tests are reported
quantitatively
64
specific; if RPR is positive, we order one of these; CONFIRMATORY TEST; measure antibody against T. pallidum antigens; qualitative; reactive for life
treponemal tests
65
FTA-ABS (fluorescent treponemal antibody test), Treponemal agglutination test (MHA-TP or microhemagglutination test)
examples of treponemal tests
66
penicillin for treatment of t. pallidum is injected
IM
67
lab id of Borrelia burgdorferi
weakly gram negative, darkfield microscopy, immunofluorescence; LARGE, 3-10 COILS, ABUDANCE OF PERIPLASMIC FLAGELLA
68
borrelioses is transmitted by
arthropod vector
69
what does borrelia burgdorferi cause?
Lyme disease
70
lyme disease is transmitted by
Ixodes tick -- black legged deer ticks
71
what is the most common vector-borne disease in the U.S.?
Lyme disease
72
Nonfatal, slowly progressive syndrome that mimics neuromuscular and rheumatoid conditions if untreated
lyme disease
73
bull's eye rash called
erythema migrans (lyme disease)
74
in lyme disease is untreated it can disseminate and progress to
cardiac damage, neurological symptoms and polyarthritis
75
tx for lyme disease
doxycycline for 8 years and above; amoxicillin for 8 and younger
76
why do we not give 8 and younger doxycycline?
causes tooth deformities and discoloration
77
prevention against lyme disease
DEET
78
small, gram-negative, fastidious but not obligate parasites
bartonella henselae lab id
79
trench fever
bartonella quintana -- spread by human lice
80
bartonella henselae causes
cat-scratch disease
81
cat-scratch disease
lymphatic infection associated with a clawing injury by cats
82
starts as a small patch/cluster of papules at site within 7 days, then spreads via lymphatics to draining regional lymph nodes --> progresses to tender, regional lymphadenopathy within 1-2 weeks; can lead to bacteremia and endocarditis in IC; usually self-limiting
bartonella henselae (cat-scratch disease)
83
obligate INTRACELLULAR parasitic bacteria; small, gram-negative cell wall
chlamydiae
84
chlamydia lab testing
Direct nucleic acid antigen testing (NAAT) from patient swab samples
85
what type of samples do you need to check for chlamydiae on NAAT?
male: urethral swab or urine
female: cervical swab
86
STD, neonatal and ocular disease
chlamydia trachomatis
87
ATYPICAL PNEUMONIA
chlamydophila pneumoniae
88
pt presents with fever, dry cough, sore throat, HOARSENESS/LARYNGITIS
chalmydophila pneumoniae
89
dx of chlamydophila pneumoniae
culture; immunofluorescence microscopy
90
zoonotic atypical pneumonia usually transmitted from BIRDS
chlamydoophila psittaci
91
chlamydophila psittaci causes
atypical pneumonia and can lead to endocarditis, myocarditis, encephalitis
92
pathogenisis of c. trachomatis
infects columnar epithelial cells
93
when c. trachomatis gets into the urogenital tract -->
urethritis, cervicitis, prostatitis, PID, lymphogranuloma venereum
94
when c. trachomatis gets into the conjunctiva
trachoma, conjunctivitis
95
manifestations of c. trachomatis
trachoma, reiter's syndrome, lymphogranuloma venereum, urethritis
96
severe infection of the epithelial cells of the eye causing deformity of eyelids & cornea, can cause blindness --> typically seen in neonates of mothers who were not treated
trachoma (caused by c. trachomatis)
97
trio of arthritis, urethritis, and conjunctivitis
reiter's syndrome (caused by c. trachomatis)
98
caused by the invasion of lymphatic tissue of the genitalia --> leads to disfiguring disease of the external genitalia and pelvic lymphatics
lyphogranuloma venereum (caused by c. trachomatis)
99
clinical appearance of advanced lymphogranuloma venerum
chronic local inflammation blocks the lymph channels, causing swelling and distortion of the external genitalia
100
most common sexually transmitted disease in both men and women -- more common than gonorrhea and syphilis combined
chlamydia trachomatis urethritis
101
#1 bacterial STD
chlamydia trachomatic urethritis
102
pts are often asymptomatic; males: nongonoccocal urethritis (NGU) -- can cause mild dysuria, mild discharge; females: urethritis can lead to cervicitis and PID -- can elicit a yellowish-whitish discharge and or dysuria (BUT 90% ARE ASYMPTOMATIC)
chlamydia trachomatis urethritis
103
lab id of rickettsia rickettsii
OBLIGATED INTRACELLULAR parasitic bacteria; gram-negative; non-motile pleomorphic rods
104
ticks, fleas, & lice are involved in their life cycle
ricketssia rickettsii
105
have tropism for endothelial cells --> enter vascular endothelial cells & cause NECROSIS of the vascular lining --> vasculitis, vascular leakage & PINPOINT HEMORRHAGING in vessels of the heart and lungs
rickettsia rickettsii
106
ricketssia rickettsii causes
rocky mountain spotted fever
107
what usually carries rickettsia rickettsii
dogs and wood ticks
108
second most common tick-borne disease
rickettsia rickettsii (rock mountain spotted fever)
109
engulfed by endothelial cells via endocytosis and takes over the cells machiner --> spreads through the bloodstream or the lymphatics and causes widespread damage to the SMALL BLOOD VESSELS (vasculitis) --> leads to hemorrhage, increased vascular permeability, edema, and the activation of inflammatory and coagulation mechanisms
patho of rickettsia rickettsii
110
onset usually between 207 days after exposure; fever, chills, HA, n/v, myalgias; DISTINCT SPOTTED RASH THAT OCCURS WITHIN 2-5 DAYS OF ONSET OF FEVER
s/sx of rickettsia rickettsii (rocky mountain spotted fever)
111
blanching erythematous rash with mucules that become petechial over time
rocky mountain spotted fever -- rickettsia rickettsii
112
rash begins on the ankles and wrists and spreads to the trunk (inclusion of the palsm and soles at later stage)
rickettsia rickettsii; rocky mountain spotted fever
113
T/F all patients get the erythematous rash with macules that become petechial over time in rocky mountain spotted fever
false
114
mycoplasma lab id
naturally lack cell walls, highly pleomorphic, attachment tip
115
walking pneumonia
mycoplasma pneumoniae
116
common cause of pneumonia in children and young adults; most common cause of atypical community acquired pneumonia
mycoplasma pneumoniae
117
pt presents with gradual onset of sx: FEVER, malaise, persistent and slowly worsening DRY COUGH; HA, chills and sore throat
mycoplasma pneumoniae
118
what does a chest XR of mycoplasma pneumoniae usually show?
patchy infiltrates
119
dx of mycoplasma pneumoniae
serology or PCR
120
causes GU tract infections; historically regarded to be weak sexually transmitted pathogens but now linked to PID in women and urethritis in men
Mycoplasma genitalum
121
average duration of incubation stage of syphilis
3 weeks
122
clinical setting of syphilis incubation stage
no lesion; treponemes adhere and penetrate the epithelium; after multiplying, they disseminate
123
clinical setting: initial appearance of chancre at inoculation site; intesnse treponemal activity in body; chancre later disappears
primary stage of syphilis
124
average duration of primary stage of syphilis
2-6 weks
125
diagnosis of syphilis during primary stage of syphilis
dark-field microscopy; VDRL, FTA-ABS, MHA-TP testing
126
clinical setting: healed chancre; little scarring; treponemes in blood; few if any sypmtoms
primary latency stage of syphilis
127
average duration of primary latency stage of syphilis
2-8 weeks
128
dx during primary latency stage of syphilis
serological tests
129
clinical setting: skin, mucous membrane lesions; hair loss;patient highly infectious; fever, lymphadenopathy; symptoms can persist for months
secondary stage syphilis
130
average duration of secondary stage of syphilis
2-6 weeks after chancre leaves
131
dx of syphilis during secondary stage
dark-field testing of lesions; serological tests
132
clinical setting: treponemes quiescent unless relapse occurs; lesions can reappear
latency stage of syphilis
133
average duration of latency stage of syphilis
6 months to 8 or more years
134
dx of syphilis during latency period
seropositive blood test
135
clinical setting: neural, cardiovascular symptoms; gumma develop in organs; seropositivity
tertiary stage of syphilis
136
average duration of tertiary stage of syphilis
variable; up to 20 years
137
dx of syphilis during tertiary stage
treponeme may be demonstrated by DNA analysis of tissue
138
what is the tx for syphilis
Benzathine penicillin G, 2 x 10^6 units; doxycycline
