Bacteria (Part IV) Flashcards
1
Q
What are the gram negative pathologic bacteria-enteric bacteria- that cause respiratory infections? (3)
A
Bordetella pertussis, Legionella pneumophilia, Haemophilius influenzae
2
Q
What are the general characteristics of Legionella pneumophilia (gram stain, shape, a(n)erobic, intra or extracellular?
A
gram negative rod, aerobic, facultative intracellular organism (survives in macrophages)
3
Q
How does legionella pneumophilia cause infection?
A
it is aerosolized: found in water systems: cooling towers, condensers, showers, tubs
4
Q
Where can legionella pneumophilia live?
A
inside free living amoebas and in biofilms
5
Q
What 2 specific diseases can Legionella pneumophilia cause?
A
Pontiac fever and Legionnaires’ disease
6
Q
how does Pontiac fever present?
A
self-limited febrile illness (2-5 days): fever, chills, myalgia, malaise, headache
7
Q
how does Legionnaires’ disease present?
A
it is more severe: multilobular pneumonia with abscess; fever, chills, cough, can lead to multiorgan dysfunction and death
8
Q
what are the general characteristics of Haemophilus influenza (gram stain, shape)?
A
pleomorphic gram negative rod or coccobacillus
9
Q
what do all haemophilus species require for growth? And where are these found
A
hemin and NAD (X and V factors); both are found in blood
10
Q
where must Haemophilus influenza grow?
A
chocolate agar- it cannot grow on routine blood agar
11
Q
what does the encapsulated strain of Haemophilus influenza allow?
A
it is much more virulent and allows blood stream invasion
12
Q
what is the most important and most virulent encapsulated strain of haemophilus influenza?
A
Haemophilus influenza type B (Hib)
13
Q
what is haemophilus influenza type B (Hib) well known for?
A
early childhood meningitis
14
Q
when is the Hib vaccination series given?
A
during the first 1 1/2 years of life
15
Q
Besides early childhood meningitis, what else does encapsulated Haemophilus influenza type B cause?
A
acute epiglottitis
16
Q
how does acute epiglottitis present?
A
fever, sore throat leading to severe wheezing, drooling
17
Q
when do disease manifestations of encapsulated H. influenza occur?
A
at 6 months to 3 years- after disappearance of maternal antibodies
18
Q
what does unencapsulated haemophilus influenza cause?
A
otitis media
19
Q
What are the general characteristics of Haemophilius ducreyi? (gram stain, shape, and requirements for growth)?
A
gram negative coccobacillus, X and V factors (hemin and NAD) required for growth
20
Q
how does Haemophilius ducreyi look when stained?
A
clumping of bacteria likened to a school of fish
21
Q
how is Haemophilius ducreyi transmitted?
A
sexually transmitted
22
Q
what is the effect of Haemophilius ducreyi infection?
A
a painful genital ulcer known as a chancroid; can also cause a painful unilateral suppurative (pus forming) inguinal lymphadenopathy
23
Q
where is haemophilius ducreyi endemic to?
A
developing regions in asia africa and caribbean
24
Q
what organisms cause a painful genital lesion?
A
haemophilius ducreyi and HSIVI and II virus
25
what are the general characteristics of Garderella vaginalis? (gram stain and shape)
gram negative to variable rod
26
what is the effect of garderella vaginalis?
bacterial vaginitis
27
how does garderella vaginalis detected on pap smear?
as "clue cells": squamous epithelial cells with mixed flora replacing normal flora
28
what is the presentation of infection of garderella vaginalis?
malodorous "fishy smelling" discharge, pruritus, and dysuria
29
What are the gram negative zoonotic bacilli? (4)
yersinia pestis, francisella tularensis, brucella species, and Pasteurella multocida
30
what are the facultative intracellular gram negative zoonotic bacilli?
Yersinia, Francisella, and brucella
31
what are the general characteristics of yersinia pestis? (gram stain, shape)
gram negative zoonotic rod; BIPOLAR SHAPE
32
what is historically known about yersinia pestis?
it was responsible for the bubonic plaque
33
what is the reservoir for yersinia pestis?
found in wild rodents and prairie dogs; transferred to rats during epidemics
34
what is the vector for yersinia pestis?
fleas
35
what were the symptoms of the bubonic plague?
hemorrhage under skin; lymph nodes become hot and painful, fever, headache
36
what happens/ what is the effect of yersinia pestis being spread by aerosolized particles from human to human?
a severe atypical pneumonia
37
what are the general characteristics of francisella tularensis? (gram stain and shape)
gram negative zoonotic rod
38
how is infection with francisella tularensis most commonly obtained?
by handling rabbits or via tick/deerfly bite
39
what are the effects of francisella tularensis?
ulceroglandular tularenia and pneumonic tularemia
40
how does ulceroglandular tularemia present?
similar presentation to bubonic plague except presents with a skin ulcer
41
what is the key difference between yersinia pestis and francisella tularemia?
a characteristic primary ulcer occurs at the site of the fly or tick bite in francisella
42
what are the general characteristics of brucella specieis? (gram stain and shape)
gram negative zoonotic rod
43
what causes brucella infections? Who is at risk?
those who have contact with domesticated animal products, drinking unpasteurized milk, contact with infected meats, placental tissue
44
what are the features of brucella infections?
undulant fever, headache, night sweats, joint and muscle pain, splenomegaly; hematologic abnormalities can occur including anemia and leukopenia
45
what is an undulant fever?
fever spikes during the day and decreases at night
46
What are the general characteristics of pasteurella multocida? (gram stain and shape)
gram negative zoonotic NOT INTRACELLULAR
47
where is pasteurella multocida found?
normal flora of cats and dogs; often results after bite or cat scratch
48
what is unique about pasteurella multocida when compared to the other gram negative zoonotic organisms?
it is a facultative anaerobe: it can cause localized wound infection (cellulitis)
49
What are the general characteristics of Bartonella species? (stain and shape)
gram negative rod
50
how is bartonella henselae transmitted?
by cat scratch or bite
51
what are the effects of infection with Bartonella henselae?
cat scratch fever; regional low grade fever, malaise, lymphadenopathy, it is self limiting
52
besides the febrile illness, what else can bartonella henselae cause?
bacillary angiomatosis
53
what is bacillary angiomatosis?
a vascular proliferative disease consisting of numerous small vascular lesions which occur in the immunocompromised
54
What are the obligate intracellular bacteria?
chlamydia species, Rickettsia species, Coxiella burnetti, and Ehrlichia chaffeensis
55
What are the general characteristics of chlamydia species? (stain, size, intra-extracellularity)?
gram negative, tiny obligate intracellular bacteria
56
what do chlamydia species have a predilection to?
mucosal epithelial cells
57
What is chlamydia trachomatis?
the most common bacterial sexually transmitted infection; exclusively a human pathogen
58
what is chlamydia trachomatis a common cause of?
neonatal blindness worldwide
59
how does transmission of chlamydia trachomatis occur?
through direct contact
60
What is the effect of chlaymydia trachomatis?
non-gonococcal urethritis: dysuria, discharge in men; dysuria, increased frequency in women; men can occasionally have epididymitis; women can have mucopurulent cervicitis leading to PID
61
What is trachoma?
a chronic eye infection caused by certain serotypes of chlamydia; spread by flies
62
What is lymphogranuloma venereum cause by?
caused by the L1, L2, and L3 serotypes of chlamydia trachomatis
63
what does lymphogranuloma venereum cause?
a tender suppurative (or pus forming) inguinal lymphadenitis which can ulcerate
64
besides chlamydia trachomatis, there are two other chlamydial organisms which can cause what?
Chlamydia pneumoniae and chlamydia psittaci- both cause atypical PNA
65
how does the mild atypical pneumonia caused by chlamydia present?
dry cough, low grade fever with patchy interstitial inflammatory changes
66
how is chlamydia pneumoniae PNA spread?
community acquired direct spread
67
how is chlamydia psittaci "psittacosis" atypical PNA spread?
transmitted from bird exposure (bird feces and dried out feathers)
68
what are the general characteristics of Rickettsia species? (gram stain and shape)
gram negative pleomorphic coccobacillus form
69
what are Rickettsia species transmitted by?
arthropod vectors
70
most rickettsia species are what test positive? and what does this mean?
Weil-Felix test positive: they show agglutination by OX antibodies
71
how do Rickettsia species present?
fever, headache, rash, thrombocytopenia
72
what does Rickettsia rickettsii cause?
Rocky mountain spotted fever
73
what is the vector for Rickettsia rickettsii?
ticks
74
what is the reservoir for Rickettsia rickettsii?
dogs, rabbits, wild rodents
75
what are the symptoms associated with R. Rickettsii infection aka rocky mountain spotted fever?
fever, headache, centripetal rash including palms and soles
76
where is R. rickettsii prevalent?
central and southeast US
77
causes of rickettsial infection also often show what?
thrombocytopenia
78
what does a centripetal rash mean?
it starts on the wrists and ankles and spreads to the trunk
79
What is unique about R. akari?
they are Weil-Felix negative
80
what is the most prominent sign of rickettsialpox?
a blister/eschar at bite site
81
What are the general characteristics of coxiella burnetti (Q fever)?
obligate intracellular gram negative bacteria
82
where is coxiella burnetti found?
in domesticated animals such as cattle, sheep, and goats
83
how can coxiella burnetti be transmitted?
through the dust and air especially during the birthing, killing, and butchering of animals
84
what does coxiella burnetti: Q fever present with?
fever, headache, atypical pna
85
What is ehrlichia chaffeensis?
tick born illness which causes ehrlichiosis
86
how does ehrlichiosis present?
it is a similar disease as rocky mountain spotted fever but typically NO RASH; fever headache malaise present
87
where is Ehrlichia chaffeensis common?
same range as rocky mountain spotted fever: southeast and central US
88
What is a general description of the spirochetes?
they are gram negative, corkscrew bacteria, with spinning motility and difficult to culture
89
What are the 3 different species in the spirochetes group?
treponema, borrelia, and leptospira
90
how are spirochetes diagnosed?
by dark-field microscopy, silver stains, and serologic testing
91
What is the main disease/illness caused by treponema pallidum?
syphilis
92
how is syphilis transmitted?
sexually transmitted disease by skin to skin contact
93
how does syphilis present? what are the stages of the illness?
1. primary syphilis 2. Secondary syphilis 3. tertiary syphilis
94
what occurs in primary syphilis?
a painless chancre develops after 3-6 weeks of contact (typically in genital region)
95
what occurs in secondary syphilis?
6 weeks after the primary infection, individuals can get a condyloma lata, a macular red rash (on the palms and soles), patchy hair loss, lymphadenopathy
96
what occurs in tertiary syphilis?
6-40 years after secondary infection: gummatous lesions, thoracic aortic aneurysm, and neurosyphilis
97
what are the symptoms of neurosyphilis?
subacute meningitis, tabes dorsalis
98
when does tabes dorsalis occur and what is the effect?
occurs when syphilis affects the posterior columns of the spinal cord resulting in decreased coordination, loss of pain/temperature sensation, and diminished proprioceptive and vibratory sensation
99
what is Argyll robinson pupils?
syphilitis lesion involving the midbrain; pupil constrict to focus on near object but they do not react to light
100
infants with congenital syphilis present with what?
mucous membrane involvement in the first 3 weeks of life termed "snuffles"
101
what is secondary syphilis in infants?
rash including palms and soles, condyloma lata
102
what is the time frame for congenital syphilis?
within the first 2 years of birth
103
what is the time frame for late congenital syphilis?
>2 years after birth
104
what are the findings of late congenital syphilis?
tertiary syphilis (cardiovascular typically spared); neurosyphilis (8th cranial nerve involvement deafness) bone and teeth involvement
105
what are the teeth defects seen in late congenital syphilis?
Hutchinson's teeth: central tooth notching
106
what are the bone defects seen in late congenital syphilis?
Saber shins: bowing of the tibia
107
How do you diagnose syphilis if it is in the primary and secondary active forms?
dark field microscopy of chancre, rash, or condyloma latum
108
What does infection with Borrelia burgdorferi cause?
lyme disease
109
How is lyme disease transmitted?
by blacklegged Ixodes ticks
110
what is the reservoir for lyme disease?
deer
111
where is lyme disease commonly found?
northeast US, upper midwest
112
what is the most common tick borne illness?
Lyme disease
113
How does the early localized disease of lyme disease present?
10 days after tick bite: erythema migrans: bulls-eye rash at tick bite; flu like symptoms
114
what are the signs of early disseminated disease of lyme disease?
it can involve the nervous system, heart and joints; Bell's palsy, neuropathy, or meningitis can occur
115
What is a big clue of early disseminated disease of lyme disease?
if there is a unilateral warm joint (especially the knee) with concomitant fever
116
What are the signs of late disease of lyme disease?
chronic arthritis and encephalopathy (memory impairment and somnolence)
117
What is a unique feature of mycobacterium?
they are acid fast
118
what are the 3 important mycobacteria?
m. tuberculosis, M. leprae, and M. avium complex
119
how is m. tuberculosis spread?
respiratory aerosolization from person to person
120
who is at more of a risk for m. tuberculosis?
immunocompromised especially HIV patients
121
what are the major countries with m. tuberculosis?
china, southeast asia, africa
122
what is the body's response to mycobacterium?
cell mediated immune response- the mycobacterium is taken up by alveolar macrophages which activate a T helper 1 cell
123
what is the result of the cell mediated immune response to mycobacterium?
a necrotizing granulomata
124
In tuberculosis most of the damage is caused by what?
the necrotizing granulomata not the actual organism
125
what acts as the virulence factor for mycobacterium?
mycosides
126
what happens once tuberculosis is breathed in?
it travels to the distal portion of the airspaces when it often times implants in the middle lobe; primary infection begins in the lung
127
who is at risk for primary symptomatic tuberculosis?
immunocompromised, elderly, and young
128
how does primary symptomatic tuberculosis present?
fever, chest pain, hilar lymphadenopathy, and effusion
129
What is a Ghon complex?
a focus of subpleural tuberculosis with associated lymphadenopathy
130
What is secondary tuberculosis?
it arises from a previously infected host, often through reactivation of a latent infection
131
when might secondary tuberculosis appear?
months to years after the primary infection
132
how does secondary tuberculosis present?
insidious onset- low grade fever, night sweats, and hemoptysis
133
reactivated tuberculosis classically involves what?
the upper lobes of the lungs because of the relatively higher oxygen tension
134
what are two important patterns of spread of secondary tuberculosis?
Pott's disease and miliary tuberculosis
135
what is miliary tuberculosis?
widespread disseminated disease throughout multiple organs with innumerable lesions throughout the organs
136
what is Pott's disease?
involvement of tuberculosis of the spine
137
what is the most common extrapulmonary manifestation of tuberculosis?
Pott's disease
138
how is tuberculosis diagnosed?
Screening: tuberculin skin test and interferon-gamma release assays
139
when might you suspect primary tuberculosis on chest x-ray?
if you identify a Ghon complex
140
when might you suspect secondary active tuberculosis on chest xray?
something in the uper lobes
141
what does m. leprae cause?
leprosy (hansen's disease)
142
where is leprosy prevalent?
certain developing countries- india brazil and indonesia
143
what is m leprae carried in?
in armadillos in southern US
144
leprosy is a disease of primarily the skin and superficial soft tissue- why?
it preferentially grows at lower temperatures
145
there are different manifestations of leprosy including what two?
tuberculoid leprosy and lepromatous leprosy
146
what is occurring in tuberculoid leprosy?
a strong cell mediated response (THelper 1 and IFN-gamma)
147
what is the effect of the strong cell mediated response that is occurring in tuberculoid leprosy?
localized skin lesions, granulomatous inflammation; typically involves unilateral skin/nerve; loss of nerve sensation
148
what is occurring in lepromatous leprosy?
there is no or minimal cell mediated immune response
149
what is the result of the minimal cell mediated immune response that is occurring in lepromatous leprosy?
the organisms are allowed to replicate unchecked- skin lesions typically occur all over the body with disfigurement including loss of digits of the hand
150
Where is mycobacterium avium complex species found?
fairly ubiquitous in nature and even found in municipal water sources
151
what effect does MAC cause in immunocompetent people?
a very low grade non specific atypical PNA which presents with cough, general fatigue/malaise and maybe SOB
152
What is important to remember about MAC?
it is a very common opportunistic infection in HIV patients with CD4 T cell count less than 50
153
how does MAC infection present in HIV patients with CD4 T cell count less than 50?
unexplained weight loss, fever, diarrhea
154
what are the three bacteria without cell walls?
mycoplasma pneumoniae, mycoplasma genitalium, and ureaplasma urealyticum
155
what is the smallest bacteria?
mycoplasma pneumoniae
156
what is the effect of mycoplasma pneumoniae?
very mild or self limited bronchitis and PNA; it is a very common cause of atypical PNA in teenagers and young adults
157
how is mycoplasma pneumoniae diagnosed?
cold agglutinins
158
what is mycoplasma pneumoniae associated with?
erythema multiforme
159
what is erythema multiforme?
target looking lesions, first seen on the backs of hands/ tops of feet with eventual spread down the limbs towards the trunk
160
what does mycoplasma genitalium infection cause?
non-gonococcal urethritis
161
what does ureaplasma urealyticum infection cause?
non-gonococcal urethritis
