M5 PART 4 Flashcards
1
Q
- the most common form of enterococcal infections
- frequently associated with indwelling catheters, instrumentation, or structural abnormalities of the genitourinary tract
A
UTI
2
Q
Enterobacteriaceae
MOTILITY
A
motile w/ peritrichous flagella or nonmotile
3
Q
Enterobacteriaceae
oxygen requirement
A
facultative anaerobes
4
Q
Enterobacteriaceae
grow well on what medium
A
MacConkey agar
5
Q
Enterobacteriaceae
____ fermenters, often with gas production
A
glucose
6
Q
Enterobacteriaceae
reduce ____ to ____
A
nitrate to nitrite
7
Q
Enterobacteriaceae
catalase ____
oxidase ____
A
catalase positive
oxidase negative
7
Q
- Gram-negative rods
- Either motile with peritrichous flagella or nonmotile
- Grow on peptone or meat extract media without the addition of sodium chloride or other supplements;
- Grow well on MacConkey agar;
- Grow aerobically and anaerobically (are facultative anaerobes);
- Ferment rather than oxidize glucose, often with gas production
- Are catalase positive, oxidase negative
- Reduce nitrate to nitrite
A
Enterobacteriaceae
8
Q
Enterobacteriaceae
LACTOSE FERMENTED RAPIDLY
A
Klebsiella
Escherichia coli
Enterobacter aerogenes & cloacae
KEE
9
Q
A
10
Q
Enterobacteriaceae | ANTIGENIC STRUCTURE
most external part of the CELL WALL lipopolysaccharide and consist of repeating units of polysaccharide, resistant to heat and alcohol and usually are detected by bacterial agglutination
A
O antigen
11
Q
Enterobacteriaceae | ANTIGENIC STRUCTURE
- external to O antigens on some but not all Enterobacteriaceae, “Kapsule”
- may be associated with virulencce
A
K antigens
12
Q
Enterobacteriaceae | ANTIGENIC STRUCTURE
located on flagella and are denatured or removed by heat or alcohol
A
H antigens
13
Q
The most frequent sites of clinically important infection are the urinary tract, biliary tract, and other sites in the abdominal cavity, but any anatomic site (e.g., bloodstream, prostate gland, lung, bone, and meninges) can be the site of disease.
A
Escherichia coli
14
Q
A
15
Q
Escherichia coli
____ inhibits adhesion of E. coli to the urothelium
A
cranberry juice
16
Q
A
17
Q
Escherichia coli
Infection in kidney
A
cystitis
18
Q
- the most common cause of UTI
- accounts for 90% of first UTI in young women
A
Escherichia coli
19
Q
Escherichia coli
____ may be highly susceptible to E. coli sepsis because they lack IgM antibodies
A
newborns
20
Q
Escherichia coli
Newborns may be highly susceptible to E. coli sepsis because they lack ____ antibodies
A
IgM
21
Q
Escherichia coli
Sepsis may occur ____ to urinary tract infection
A
secondary
22
Q
Escherichia coli
E. coli and group B streptococci are the leading causes of ____ in infants.
A
meningitis
23
Q
Escherichia coli
Approximately 80% of E. coli from meningitis cases have the ____
A
K1 antigen
24
# **E. COLI ASSOCIATED DIARRHEAL DISEASES**
* EPEC adhesion factor (EAF) and chromosomal locus of enterocyte effacement (LEC) **promote tight adherence to the intestine**
* Severe, **watery** diarrhea, vomiting and fever in **infants**
**Enteropathogenic**
E. coli
25
# **E. COLI ASSOCIATED DIARRHEAL DISEASES**
* ETEC colonization factors (pili known as colonization factor antigens [CFA]) that **allows attachment to small intestine**
* **Traveler’s disease**, diarrhea in children
**Enterotoxigenic**
E. coli
26
# **E. COLI ASSOCIATED DIARRHEAL DISEASES**
* Produces **two** antigenic forms of toxins: **Shiga-like toxin 1 and 2**
* Mild **non-bloody** diarrhea, hemorrhagic colitis (**bloody diarrhea**), **severe form** of diarrhea, hemolytic uremic syndrome (a disease resulting to acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia)
**Shiga toxin-producing**
E. coli
27
# **E. COLI ASSOCIATED DIARRHEAL DISEASES**
* **Invades** and **destroy** the **mucosal cells** of the **colon**
* **Shigellosis-like**, occurs in **children in developing countries** and in travelers to these countries
**Enteroinvasive**
E. coli
28
# **E. COLI ASSOCIATED DIARRHEAL DISEASES**
* They are characterized by their **specific patterns of adherence** to **human cells**. This group of **diarrheagenic E. coli** is **quite heterogeneous**, and the exact pathogenic mechanisms are still **not completely elucidated**.
* **Acute and chronic diarrhea** (>14 days in duration) in persons in **developing countries**, cause of **foodborne illnesses** in **industrialized countries** and have been associated with **traveler's diarrhea** and **persistent diarrhea in patients with HIV**
**Enteroaggregative**
E. coli
29
30
# **Escherichia coli** | TREATMENT
CYSTITIS
TMP-SMZ or nitrofurantoin
31
# **Escherichia coli** | TREATMENT
PYELONEPHRITIS
**ciprofloxacin** or **ceftriaxone**
32
# **Escherichia coli** | TREATMENT
SEPSIS
3rd gen **cephalosporins** with or without aminoglycosides
33
# **Escherichia coli** | TREATMENT
NEONATAL MENINGITIS
**ampicillin** and **cefotaxime**
34
35
35
36
# **Klebsiella pneumoniae**
Has a **very large** polysaccharide ____
capsule
37
# **Klebsiella pneumoniae**
Produce a **lobar** ____ with **thick**, **mucoid**, **blood sputum**
pneumonia
38
# **Klebsiella pneumoniae**
**mucoid sputum** is also called
currant jelly
39
* found **outside** the enetric rod
* has **K1 antigen** (K - kapsular antigen)
* **rapid** lactose former
* produce **lobar pneumonia**
* produce **mucoid sputum (currant jelly)**
KLEBSIELLA PNEUMONIAE
40
# **ENTEROBACTER**
may cause ____ infections
nosocomial
41
* *E. cloacae* complex and *E. aerogenes*
* found in soil, water, sewage system
* common cause of **nosocomial** infections (**hospital acquired** infections)
* known to be **resistance** because of the** β-lactamase** called **ampC**
* **rapid** lactose former
ENTEROBACTER
41
# **ENTEROBACTER**
known to be **resistant** to **ampicillin** first- and 2nd gen **cephalosporins** because of the ____
β-lactamase called ampC
41
# **Serratia marcescens**
produce a **red pigment** called
PRODIGIOSIN
41
# **Serratia marcescens**
**site** of infection
urinary tract
42
# **Serratia marcescens**
**drug resistant** because of
ampC β-lactamase
43
* produce a characteristic **red pigment** (**prodigiosin**)
* Most **common sites of infection** include the **urinary tract**
* **resistant** to penicillin, ampicillin, and first-generation cephalosporins because it harbors an inducible, chromosomal **AmpC ß-lactamase**
SERRATIA MARCESCENS
43
# **Proteus**
motility
swarming motility
44
* Exhibit swarming motility
* Urease **positive** → **stone formation** (**struvite**)
* *P. mirabilis* & *P. vulgaris*
PROTEUS
44
# **Proteus**
* **urinary tract infections**
* **bloodstream infection** (frequently **secondary** due to a UTI)
* **respiratory tract infections**
P. mirabilis
44
# **Proteus**
urease ____
positive
45
# **Proteus**
* **wound** and **soft tissue** infections
P. vulgaris
45
# **Morganella morganii**
typically **resistant** to ____
penicillin
46
* Cause of **UTI** and **wound infections** in the **hospital**
* **Drug-resistant** (penicillin, cephalosporins)
Morganella morganii
47
# **Providencia**
associated with ____
UTI
48
* can cause urinary tract infections, sepsis, respiratory tract infections, intraabdominal infections, and wound infections, principally among **immunocompromised** and/or **debilitated hospitalized patients**
* Citrate test: Citrate positive
CITROBACTER
49
# **CITROBACTER**
can cause **urinary tract infections**, sepsis, respiratory tract infections, intraabdominal infections, and wound infections, principally among ____ and/or debilitated hospitalized patients
immunocompromised
50
Enterobacteriaceae species **TREATMENT**
**No single therapy is available**
Sulfonamides, ampicillin, cephalosporins, fluroquinolones, and aminoglycosides
51
# **Shigellae**
antigen present
somatic O antigen
52
# **Shigellae**
can cause the **most severe human infection**
Shigella dysenteriae
53
# **Shigellae**
have a very **low** ____
infective dose
| **highly communicable**
54
# **Shigellae**
incubation period
1 - 4 days
55
# **Shigellae**
**infections** are almost always **limited** to ____
gastrointestinal tract
56
# **Shigellae**
toxin produced
shiga toxin
56
# **Shigellae**
mode of transmission
food, fingers, feces, flies
person - person
56
# **Shigellae**
reservoir
humans
| only reservoir
57
# **Shigellae**
can only **ferment**
glucose
| non lactose fermenter
58
# **Shigellae**
bloody diarrhea
Shigellosis / Bacillary dysentery
58
# **Shigellae**
**only** **lactose** fermenter but **SLOW** lactose fermenter
Shigella sonnei
59
# **Shigellae**
positive result in **TSI**
whole agar is yellow
60
# **Shigellae**
type 1 **hemolytic uremic syndrome**
S. dysenteriae
61
# **Shigellae**
**Reiter's** chronic arthritis syndrome
S. flexneri
62
# **Shigellae**
disease
Shigellosis or Bacillary dysentry
63
# **Shigellae**
treatment for **severe** infections
ciprofloxacin
64
# **SALMONELLA**
antigens
cell wall O, flagellar H, capsular Vi
65
# **SALMONELLA**
TYPHOIDAL
S. Typhi
S. Parathypi A
66
# **SALMONELLA**
* **severe**, **systemic illness**, caused by Salmonella Typhi (**most common**) or Salmonella Paratyphi
* The fever rises to a **high plateau** (39°C to 40°C)
* from **food** or **water**
* fever, malaise, headache, constipation, bradycardia, and myalgia
ENTERIC FEVER / TYPHOID FEVER
66
# **SALMONELLA**
ENTERIC / THYPOID FEVER:
**incubation period**
10 - 14 days
67
# **SALMONELLA**
**enlargement** of ____
spleen & liver
68
# **SALMONELLA**
**spots** observed on the chest and abdomen
ROSE SPOTS
69
# **SALMONELLA** | TREATMENT
uncomplicated
oral azithromycin
70
# **SALMONELLA** | TREATMENT
complicated
parenteral
3rd gen cephalosporion or fluoroquinolone
71
# **SALMONELLA** | PREVENTION
oral
live attenuated vaccine
72
# **SALMONELLA** | PREVENTION
intramascular
Vi capsular polysaccharide vaccine (Typbar)
73
# **Bacteriologic Methods for Isolation of Salmonellae**
* The specimen (**usually stool**) can also be placed into **selenite F** or **tetrathionate broth**, both of which **inhibit replication** of **normal intestinal bacteria** and **permit multiplication of salmonellae**.
* After incubation for **1-2 days**, an aliquot from this broth is plated on differential and selective media.
ENRICHMENT CULTURE
74
# **SALMONELLA**
* **most common manifestation** of Salmonella infection
* severe diarrhea
ENTEROCOLITIS
74
# **SALMONELLA**
complicating Salmonella bacteremia usually involves the aorta, often associated with **atherosclerotic plaque**s or **aneurysms**; people **older than 50** years have a **higher risk** of developing such complications
endovascular infection
75
# **Bacteriologic Methods for Isolation of Salmonellae**
* **EMB**, **MacConkey**, or **deoxycholate medium** permits **rapid detection of lactose nonfermenters** (not only salmonellae and shigellae but also Proteus, Pseudomonas, etc.).
* **Gram-positive** organisms are somewhat **inhibited**.
* **Bismuth sulfite** medium permits **rapid detection of salmonellae**, which form **black colonies** because of HS production.
* Most salmonellae produce **H2S**.
DIFFERENTIAL MEDIUM
76
# **SALMONELLA | Serologic Methods**
known **sera** + **unknown culture**
AGGLITINATION TEST
76
# **SALMONELLA**
more common among patients with **comorbidities** (e.g., immunosuppression), as well as **infants** and the **elderly**
| esp those **kids** with **sickle cell anema**
BACTEREMIA
76
# **Bacteriologic Methods for Isolation of Salmonellae**
* The specimen may also be plated on **salmonella-shigella (SS) agar**, **Hektoen enteric (HE) agar**, **xylose-lysine desoxycholate (XLD) agar**, or **desoxycholate-citrate agar**, all of which **favor growth of salmonellae** and **shigellae** over other Enterobacteriaceae.
* **Chromogenic agars** specifically for salmonella recovery are also available.
SELECTIVE MEDIUM
77
# **SALMONELLA | Serologic Methods**
serum agglutinins **rise sharply** during the **second** and **third weeks** of S serotype Typhi infection.
Tube Dilution Agglutination Test (Widal Test)
78
# **SALMONELLA | Epiemiology**
sources of infection
poultry products, food & drinks
78
# **SALMONELLA | Epiemiology**
**Three percent** of survivors of typhoid fever become ____
| gallbladder, biliary tract, or rarely, the intestine or urinary tract
permanent carriers
78
# **PSEUDOMONAS AERUGINOSA**
oxygen requirement
obligate aerobe
78
# **PSEUDOMONAS AERUGINOSA**
Produces a **non-fluorescent bluish** pigment, ____, which diffuses into the agar
pyocyanin
78
# **PSEUDOMONAS AERUGINOSA**
Produces the **fluorescent** pigment ____, which gives a **greenish color** to the agar when combined with pyocyanin
pyoverdine
78
# **PSEUDOMONAS AERUGINOSA**
**dark red** pigment
pyorubin
78
# **PSEUDOMONAS AERUGINOSA**
**brown-black** pigment
pyomelanin
78
* gram **negative**
* **obligate aerobe**
* **motile** & **rod shaped**
* produces a blue pigment called **pyocyanin**
* commonly present in **moist environments** in **hospitals**
**PSEUDOMONAS AERUGINOSA**
78
# **PSEUDOMONAS AERUGINOSA** | ANTIGENIC STRUCTURES
extend from the cell surface and **promote attachment to host epithelial cells**
PILI (FIMBRIAE)
78
# **PSEUDOMONAS AERUGINOSA** | ANTIGENIC STRUCTURES
an **exopolysaccharide** is responsible for the **mucoid colonies** seen in cultures from patients with CF
ALGINATE
78
# **PSEUDOMONAS AERUGINOSA** | ANTIGENIC STRUCTURES
responsible for many of the **endotoxic properties** of the organism
LIPOPOLYSACCHARIDE
78
# **PSEUDOMONAS AERUGINOSA** | ANTIGENIC STRUCTURES
**elastases**, **proteases**, and **two hemolysins** (a heat-labile phospholipase C and a heat-stable glycolipid)
EXTRACELLULAR ENZYMES
78
# **PSEUDOMONAS AERUGINOSA** | ANTIGENIC STRUCTURES
responsible for the **production of hydrogen peroxide** and **superoxide**, and stimulates the **release of interleukin (IL)-8**
PYOCYANIN
78
# **PSEUDOMONAS AERUGINOSA** | ANTIGENIC STRUCTURES
serves as a **siderophore**, that is, **binds iron**
PYOVERDINE
78
# **PSEUDOMONAS AERUGINOSA** | ANTIGENIC STRUCTURES
**blocks protein synthesis**, causes **tissue necrosis** and is **lethal** for **animals** when injected in purified form.
EXOTOXIN
78
# **PSEUDOMONAS AERUGINOSA**
**bifunctional** enzymes with **GTPase** and **ADP-ribosyl transferase** activity
EXOENZYME S & T
78
# **PSEUDOMONAS AERUGINOSA**
phospholipase
EXOENZYME U
78
# **PSEUDOMONAS AERUGINOSA**
an adenylyl cyclase
EXOENZYME Y
78
# **PSEUDOMONAS AERUGINOSA**
produces what type of **odor**
grape-like or corn taco-like
78
* **not part** of normal human microbiota but is capable of **colonization** of various body sites
* known to cause disease in humans, especially in people with **altered** and **decreased host defenses**
**PSEUDOMONAS AERUGINOSA**
79
# **PSEUDOMONAS AERUGINOSA**
acquisition of the organism can be either ____ or ____
endogenous or exogenous
79
# **PSEUDOMONAS AERUGINOSA**
occurs **after** colonization
endogenous infection
79
# **PSEUDOMONAS AERUGINOSA**
occurs from an **environmental reservoir** via susceptible portal of entry
exogenous infection
79
# **PSEUDOMONAS AERUGINOSA**
grows well at what **temp**
37C - 42C
80
* **Comma**-shaped, **curved**, and sometimes straight
* **facultatively anaerobe**
* catalase and oxidase-**positive**
* Motile (**mono**trichous or **multi**trichous polar flagella)
* **Halophilic**
VIBRIOS
81
# **VIBRIOS**
shape
comma-shaped, curved
82
# **VIBRIOS**
catalase & oxidase
positive
83
# **VIBRIO CHOLERAE**
transmission
contaminated water & food
84
# **VIBRIO CHOLERAE**
Many vibrios share a **single heat-labile** ____ antigen
flagellar H
85
# **VIBRIO CHOLERAE**
has ____ found on the **cell wall**
O lipopolysaccharides
86
# **VIBRIO CHOLERAE**
can cause **epidemic** and **pandemic cholera**
O1 and O139
87
# **VIBRIO CHOLERAE**
associated with **cholera-like** diarrheal diseases
non-O1 and non-O139
88
# **VIBRIO CHOLERAE**
**50%** of the infections with **classic** vibrio Cholera are ____
ASYMPTOMATIC
89
# **VIBRIO CHOLERAE**
**75%** of the infections are associated with ____
El Tor biotype
90
# **VIBRIO CHOLERAE**
medium
thiosulfate-citrate-bile salts-sucrose (TCBS) agar
91
# **VIBRIO CHOLERAE**
secretes an **enterotoxin** called ____ (cholera toxin)
choleragen
92
# **VIBRIO CHOLERAE** | ENTEROTOXIN
**enters**, **closed** in an **endosome**, reaching the cytoplasm; catalyze the addition of ADP ribose to the G protein; G protein will cause the persistent stimulation of this enzyme called the adenylate cyclase and the adenylate cyclase will result to the increase of cyclic AMP – **prolonged hypersecretion of water and electrolytes**
subunit A
93
# **VIBRIO CHOLERAE** | ENTEROTOXIN
binding to the **GM1 receptor** (ganglioside receptor)
subunit B
94
# **VIBRIO CHOLERAE** | CLINICAL FINDINGS
spectrum of disease
asymptomatic to mild, moderate, or severe diarrhea
95
# **VIBRIO CHOLERAE** | CLINICAL FINDINGS
incubation period
12 hrs - 3 days
96
# **VIBRIO CHOLERAE** | CLINICAL FINDINGS
**stools** resemble
rice water
97
# **VIBRIO CHOLERAE** | TREATMENT
most important treatment
water & electrolyte replacement
98
# **VIBRIO CHOLERAE** | TREATMENT
DOC
tetracycline
99
# **VIBRIO CHOLERAE** | TREATMENT
children and in pregnant women
erythromycin / azithromycin
100
* Transmitted by contaminated **seafood** (raw fish or shellfish)
* The enteritis ranges from **mild watery** diarrhea to a **dysentery-like** syndrome (**bloody**)
Vibrio parahaemolyticus
101
# **Vibrio parahaemolyticus** | TREATMENT
DOC
doxycycline / fluoroquinolone
102
* **Severe wound** and **soft tissue infections** - Can lead to **necrosis**
* **Bacteremia/sepsis** (rather than gastroenteritis)
* Chronic liver diseases, such as **liver cirrhosis**
* Can **invade the bloodstream** even without causing GI symptoms
Vibrio vulnificus
103
# **Vibrio vulnificus** | TREATMENT
DOC
fluoroquinolones, doxycycline, 3rd gen cephalosporins
104
# **CAMPYLOBACTER JEJUNI**
shape
curved, comma, S-shaped, **SEA GULL WING** shaped
105
# **CAMPYLOBACTER JEJUNI**
oxygen requirement
macroaerophilic
106
# **CAMPYLOBACTER JEJUNI**
selective media
camply blood agar, skirrow's media
107
# **CAMPYLOBACTER JEJUNI**
grows better at ____C than 37C
42C
108
# **CAMPYLOBACTER JEJUNI**
catalase & oxidase
positive
109
* A **small motile**, Gram-**negative rod** that appears as **curved**, **comma**-, or **S**-shaped organisms
* "**Sea gull wing**" shape
* **Microaerophilic** (5-7% O2, 10% CO₂)
* Selective media – **Campy blood agar**, **Skirrow's media**
* Grows better at **42°C** than 37°C
* Catalase and oxidase-**positive**
CAMPYLOBACTER JEJUNI
110
# **CAMPYLOBACTER JEJUNI**
transmission
contaminated food & water
contact w infected animals / animal products
111
# **CAMPYLOBACTER JEJUNI** | ANTIGENIC STRUCTURE
have ____ with endotoxic activity
lipopolysaccharide
112
# **CAMPYLOBACTER JEJUNI** | CLINICAL FINDINGS
* Characterized by **abdominal cramps**, diarrhea (**bloody**), HA, malaise, and fever.
* **Self-limiting**
* The organism can occasionally **invade the bloodstream**.
* May **resemble enteric fever**
* Susceptible in **macrolides** (e.g., erythromycin)
GASTROENTERITIS
113
# **CAMPYLOBACTER JEJUNI** | CLINICAL FINDINGS
A form of **ascending paralytic** disease.
Guillain-Barré syndrome
114
* A Gram-**negative curved rod**
* spiral, curved, or **fusiform** rod-shaped
* Motile (**single** and/or **multiple** **mono**polar flagella)
* Catalase and oxidase-**positive**; **urease-positive**
* **Microaerophile**
HELICOBACTER PYLORI
115
# **HELICOBACTER PYLORI**
catalase & oxidase
positive
116
# **HELICOBACTER PYLORI**
urease
positive
117
# **HELICOBACTER PYLORI**
oxygen requirement
microaerophile
118
# **HELICOBACTER PYLORI**
transmission
person - person
| via fecal-oral route
119
* **survives** in the **acidic environment** of the **stomach** and ultimately **establish lifelong colonization** of the **gastric mucosa** through **urease activity**.
* **does not appear to invade the gastric mucosa**, but rather release various toxins
* infection is a known independent risk factor for the development of:
o Atrophic gastritis
o Gastric ulcer disease
o Gastric adenocarcinomas
o Gastric mucosa associated lymphoid tissue
(MALT) lymphomas
HELICOBACTER PYLORI
120
# **HELICOBACTER PYLORI**
reservoir
humans
121
# **HELICOBACTER PYLORI**
grows optimally at pH of
6 - 7
122
# **HELICOBACTER PYLORI** | CLINICAL FINDINGS
Acute infection typically yields an **upper gastrointestinal illness** called
food poisoning
123
# **HELICOBACTER PYLORI** | CLINICAL FINDINGS
**colonization** with H. pylori
chronic gastritis
124
# **HELICOBACTER PYLORI** | TREATMENT
triple therapy
7 - 14 days
125
# **HELICOBACTER PYLORI** | TREATMENT
quadruple therapy
10 - 14 days
