Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

DERS (GIT) > L15- GI Infections VI (inflam. diarrhea, bacteria) > Flashcards

L15- GI Infections VI (inflam. diarrhea, bacteria) Flashcards

1
Q

list the types of Salmonella, associated species, and what they cause

A

Typhoidal:

  • typhoid / paratyphoid fever
  • S. typhi, S. paratyphi A/B/C

Non-Typhoidal:

  • gastroenteritis / food poisoning
  • other Salmonellas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

list the three important Salmonella microbial features

A
  • Gram(-) rods
  • motile
  • non-lactose fermenter
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Salmonella spp. typing depends on….

A
  • O Ag, cell wall
  • H Ag, flagella
  • Capsular Vi (virulence) Ag
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Salmonella has (1) property, therefore it needs (high/low) inoculation dose

A

1- acid labile

2- large dose (many destroyed in stomach)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Typhoid Salmonella reservoir is (1), mainly transmitted via (2)

Non-typhoid reservoir is (3), mainly transmitted via (4)

A

1- humans
2- person-to-person transmission

3- humans + animals
4- contaminated foods (poultry, dairy)- note person-to-person is less common

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

list the clinical manifestations of Salmonellosis and indicate the associated species

A

Gastroenteritis: S. typhimurium, S. enteritidis, S. newport

Septicemia / Bacteremia: (rare) S. cholerasuis

Enteric / Typhoid Fever: S. Typhi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

list the complications of Salmonellosis

A

-CVS, CNS, pulmonary, hepatobilliary involvement

  • reactive arthritis
  • osteomyelitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Salmonellosis –> gastroenteritis:

  • (1) species
  • (2) main infection description
  • worse effects in (3) patients and invasive in (4) patients
  • (5) is a common associated symptom
A 
1- S. typhimurium, S. enteritidis, S. newport
2- self-limiting diarrhea
3- young, elderly
4- children, cancer, SCD Pts
5- vomiting
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Salmonellosis –> septicemia:

  • (1) species / transmission
  • defining condition in (2) patients
  • (3) clinical presentation
A

1- any species found in contaminated food / water

2- AIDS

3- fever/chills, oliguria, tachycardia, tachypnea, vomiting, diarrhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

list the risk factors for Salmonella Septicemia (in order of most importance)

A

1a) age extremes, immunosuppression, malignancy, congenital immune defects
1b) other predisposing co-morbidities (includes liver disease, hemoglobinopathies)
2) alteration to GIT by suppression of gastric acid (antacids) or antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Salmonella pathogenesis:

  • (1) route of entry
  • (2) mediates attachment
  • (3) and (4) aid in intracellular survival, where they are contained in (5)
A

(similar to Shigella, although replication in vacuoles, not cytoplasm)
1- paracellularly, M-cell endocytosis
2- SPI-1 (salmonella pathogenicity Island-1)
3- SPI-2
4- T3SS (type 3 secretion system)
5- SCV (salmonella containing vacuoles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

describe Salmonella pathogenesis (gastroenteritis)

A

1) ingestion
2) attaches to SI
3) invades M cells (Peyer’s patches) + enterocytes (PAI encoded)
4) survive/replicate w/in vacuole (PAI encoded)
5) transports across cytoplasm
6) release into blood/lymph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Enteric fever:

  • (1) organisms/spp.
  • (2) reservoir
  • (3) geographic areas
A

(Typhoid / Paratyphoid fever)
1- S. typhi, S. paratyphi A/B
2- humans (no animals)
3- Asia, Mexico, India (travelers to those places)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

describe Salmonella pathogenesis (Typhoid/Paratyphoid fever)

A

1) blood stream
2) macrophage involvement
3) transports to liver, spleen, bone marrow
4) colonization in gall bladder
5) second bacteremia
6) replication in bile
7) re-enters intestines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Enteric Fever:
-(1) is required and (2) is occasionally seen before diagnostic testing

-(3) and (4) are used in diagnostic testing

A

1- h/o travel to endemic areas
2- transient macular rash (rose-colored) on trunk

3- examination of blood: anemia, leukopenia, absence of eosinophils
4- blood culture –> S. typhi isolation (needs many samples)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

2-5% of typhoid patients exhibit _______, a very dangerous property

A
  • continued fecal excretion

- asymptomatic carrier state that allows for transmission

17
Q

Salmonella Enterocolitis:

  • (1) incubation
  • (abrupt/insidious) onset
  • (3) fever description
  • (4) duration
  • (5) GI Sxs
  • (6) blood cultures
  • (7) stool cultures
A 
1- 8-48hrs
2- abrupt
3- low grade fever
4- 2-5 days
5- n/v/d
6- negative
7- positive soon after onset
18
Q

Salmonella Septicemia:

  • (1) incubation
  • (abrupt/insidious) onset
  • (3) fever description
  • (4) duration
  • (5) GI Sxs
  • (6) blood cultures
  • (7) stool cultures
A 
1- variable
2- abrupt
3- rapid rise and spiking septic fever
4- variable
5- none
6- positive
7- infrequently positive
19
Q

Salmonella Enteric Fever:

  • (1) incubation
  • (abrupt/insidious) onset
  • (3) fever description
  • (4) duration
  • (5) GI Sxs
  • (6) blood cultures
  • (7) stool cultures
A

1- 7-20 days
2- insidious
3- gradual, high plateau, typhoidal state
4- several wks
5- early constipation, bloody diarrhea
6- positive in 1st/2nd wk
7- positive after 2nd wk (negative early on)

20
Q

Salmonella:

  • (1) appearance on initial agar
  • (2) appearance on (3) / secondary agar
  • (3) is another agar
  • (4) are the three key microbial features
A 
1- pale/colorless on MacConkey agar
2- black colonies (H2S production)
3- S-S agar (Salmonella-Shigella agar)
4- EMB (eosin methylene blue agar)
5- motile, Gram(-) rod, non-lactose fermenter
21
Q

Campylobacter spp. microbial features

A
  • small, curved spiral rods, 1.5-3.5mm x 0.2-0.4mm
  • Gram(-), motile (single falgellum), oxidase(+)
  • microaerophilic
  • selective growth at 42-43C (none at 25C)
22
Q

Campylobacter spp. are common infections in (1) countries, mainly the (2) species. (3) list the reservoirs / routes of transmission.

A

1- N. America, Europe, Australia

2- C. jejuni

3- GIT of large domestic animals: raised poultry, cows, sheep, pigs, cats, dogs
(rarely person-to-person, fecal-oral)

23
Q

Campylobacter pathogenesis:

  • ingest (1) amount of pathogen
  • invasion of (2) segment mucosal surface
  • (3) production initiated in GIT
A

1- 500-10000 organisms (low inoculation dose)

2- SI, LI

3- Endotoxin, Enterotoxin (watery diarrhea), Cytotoxin (bloody diarrhea)

24
Q

list the clinical features / symptoms of Campylobacter spp. infections (GIT)

A

(similar to Shigella, Salmonella)

  • slight vomiting, profuse diarrhea (blood stained), severe abdominal pain
  • severe prostration (getting on all fours in pain)
  • pyrexia (fever)
25
Q

list the common complications of Salmonellosis

A

1) (40%) Acute inflammatory demyelinating polyneuropathy / Guillain-Barre Syndrome
2) (1%) reactive arthritis, mostly knee joint for 6-12 mos

26
Q

C. jejuni diagnosis:

  • cultured from (1) samples
  • has (2) appearance on (3) special culture
  • (4) positive on biochemical analysis
  • similar microscopic appearance to (5)
A 
1- fecal specimen
2- grey, mucoid, (spreading)
3- Skirrow agar
4- oxidase(+), catalase(+)
5- Vibrio spp., Gram(-)
27
Q

Of the Yersinia spp., (1) causes the most GIT infections, mainly in (2) population. (3) is another species with less frequent infections. These Yersinia spp. prefers (4) climates- include geographic areas.

A

1- Y. enerocolytica
2- children 1-7y/o (more in <4y/o, or adults at daycare center)
3- Y. pseudotuberbulosis
4- cooler climates: Japan, Canada, Scandinavia

28
Q

Yersinia spp.:

  • (1) reservoirs
  • (2) most common route of transmission
  • (3) optimal growth temperature
A

1- aquatic and domestic animals (so many)

2- contaminated food, contact with infected animal/feces

3- -1C - 40C (psychotroph - facultative psychrophile)

29
Q

Yersinia spp. pathogenesis (GIT infections):

  • contains (1) toxin with (2) cellular effect
  • Sxs will mimic (3)
A

1- ST enterotoxin (chromosomal)

2- inc cGMP

3- appendicitis (if it invades ileum = pseudo-appendicitis): abdominal pain, diarrhea, fever, rarely vomiting

30
Q

Yersinia spp. clinical features (GIT infections):

  • described as (1) disease
  • (2) incubation period, (3) duration
  • (4) Sxs
A

1- self-limiting enterocolitis
2- 3-7 days
3- 14-21 days (or longer)
4- abdominal pain, diarrhea, fever, rarely vomiting (pseudo-appendicitis)

31
Q

list the defining microbial features of Yersinia spp. (GIT infections)

A
  • Gram(-), bipolar staining, coccobacilli
  • glucose(+), sucrose(+)
  • catalase(+), oxidase(+)
32
Q

Yersinia spp. (GIT infections):

  • Dx usually requires (1) sample
  • (2) appearance on initial agar, then (3) agar is used
  • (4) may also be used to aid Dx
A

1- stool sample
2- pinpoint colonies on MacConkey (48hrs)
3- specialized Yersinia media
4- Serology

33
Q

Non-Cholerae Vibrio spp.:

  • (1) and (2) are the main species, include main disease cause
  • (3) is the main source of infection
  • (4) is the main difference from V. cholera
A 
1- V. parahemolyticus --> gastroenteritis
2- V. vulnificus --> wound infection
(+ V. alginolyticus)
3- shellfish / seawater
4- encapsulated + able to invade blood
34
Q

Non-Cholerae Vibrio spp. are considered (1) organisms found in (2) environmental areas and causing (3) in 25% of patients

A

1- halophilic organisms
2- coastal waters (e.g. Gulf of Mexico)
3- inflammatory diarrhea

35
Q

V. parahemolyticus

  • (1) is main source of infection
  • produces (2) virulence factors
  • (3) are the clinical Sxs
A

1- ingestion of raw / poorly cooked seafood (Japan- raw fish, USA- shellfish)

2- enterotoxin (ST), hemolysin

3- watery diarrhea, abdominal cramps, n/v –> bloody diarrhea

36
Q

V. vulnificus:

  • most commonly found in (1) geographic area
  • (2) list the three possible resulting infections, include infection source
  • highest concern is infection in (3) patients
A

1- Gulf of Mexico

2:
-Acute gastroenteritis: raw / undercooked shellfish

  • Necrotizing wound infection: injured skin + contaminated marine water
  • Invasive sepsis: raw / undercooked shellfish (oysters) + immuno-compromised individuals

3- patients with underlying liver disease

37
Q

Non-cholera Vibrio spp. general pathogenesis and its factors

A

poorly understood

Virulence Factors:

  • capsule
  • endotoxin
  • flagellum
  • metalloprotease, hemolysin, cytolysin, phospholipase (extracellular products)
  • Heme receptors, siderophores (Fe acquisition)
  • fibronectin binding protein, pili (adherence)
38
Q

Non-Cholera Vibrio spp.:

  • (1) samples screen for (2) activity
  • (3) is the main agar with (4) as the differentiating agent- explain
A

1- stool samples
2- oxidase activity
3- TCBS: thiosulphate-citrate-bile salts-sucrose
4- sucrose:
(+): V. cholera, yellow appearance
(-): V. parahemolyticus, V. vulnificus, normal green (no color change) appearance

DERS (GIT) (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions