Unusual GNR Fermenters

Question 0

inflammation of the stomach and intestines, resulting from bacterial toxins or viral infection and causing vomiting and diarrhea

Answer 0

gatroenteritis

Question 1

Genera that are considered unusual fermenters

Answer 1

Vibrio, Aeromonas, Plesiomonas, Campylobacter

Question 2

infection of the intestines resulting in severe diarrhea with the presence of blood and mucous in the feces

Answer 2

dysentery

Question 3

Stool specimen collection requirements

Answer 3

stool or rectal swab has a two hour window if placed in a sterile cup

Question 4

Stool specimen preservatives

Answer 4

Cary Blair, Buffered Glycerol Saline, Alkaline Peptone Water, Modified Stuart’s

Question 5

Oxidase positive, fermenters of glucose, isolated in coastal areas (fresh, brackish, and salt water), associated with seafood consumption

Answer 5

Vibrio Species characteristics

Question 6

Describe vibrio morphology

Answer 6

Curved or comma shaped GNRs, polar flagella, halophilic (require Na)

Question 7

caused by Vibrio, spread by fecal-oral route, severity variable but usualy severe diarrhea, death results from massive fluid loss/shock/acidosis

Answer 7

Cholera

Question 8

notorious pathogen, no tissue invasion, enterotoxin production (adheres to small intestine), “rice water stools”

Answer 8

Vibrio cholera

Question 9

Treatment of cholera

Answer 9

fluid/electrolyte replacement; tetracycline in severe cases

Question 10

collection/transport requirements for stool/wounds (cholera)

Answer 10

stool: susceptible to desiccation, within first 24 hrs of infection, cary-blair at room temp (no buffered glycerol saline transport); wounds: sterile swabs

Question 11

What do we use to isolate cholera?

Answer 11

Thiosulfate Citrate Bile Salts Sucrose Agar (TCBS Agar), SBA, MAC

Question 12

Describe TCBS agar

Answer 12

green plate; selective and differential; sucrose fermenters (yellow colonies)/non-sucrose fermenters (green colonies)

Question 13

Hemolysis present on SBA from cholera

Answer 13

Beta

Question 14

MAC Results in cholera

Answer 14

Most Lactose Negative

Question 15

Inubation requirements for cholera

Answer 15

Ambient air at 35’C

Question 16

What methods can we use to identify cholera?

Answer 16

string test, vibrostatic test, KIA and Phase II, automation, MALDI-TOF, O1 or O139 antisera in coastal areas

Question 17

list 3 non-cholera vibrios

Answer 17

V. parahaemolyticus, V. vulnificus, V. alginolyticus

Question 18

Endemic to Japan, mild gastroenteritis (ingestion of raw fish), wound infections (contaminated seawater), Kanagawa Phenomenon, does not ferment sucrose

Answer 18

V. parahaemolyticus

Question 19

more wound infections than diarrhea (contaminated seawater), septicemia, invasive, liver disease, non-sucrose fermenting

Answer 19

V. vulnificus

Question 20

wound infections, infections of ears and eyes, infrequently isolated in clinical laboratory, ferments sucrose

Answer 20

V. alginolyticus

Question 21

straight/coccobacillary GNR, polar flagellum, inhabitants of aquatic ecosystems (fresh and brackish water); obtained from fresh produce, meat, and dairy products or exposure to aquatic source

Answer 21

Aeromonas spp

Question 22

cause gastroenteritis (mild watery, self limiting diarrhea, spring to fall seasons) and extraintestinal infections

Answer 22

Aeromonas spp

Question 23

specimen collection and transport for aeromonas spp

Answer 23

stool: Cary-Blair or buffered glycerol saline as transport; process within 2 hours
wounds: sterile swabs

Question 24

media to Isolate aeromonas

Answer 24

SBA, MAC, CIN, KIA and Phase II, automation, MALDI-TOF

Question 25

Identification of aeromonas

Answer 25

oxidase positive fermenter, vibrostatic agent O129 Test, inability to grow in 6% NaCl

Question 26

CIN media characteristics

Answer 26

Cefsulodin-irgasan-novobiocin (CIN) inhibits normal flora in stool

Question 27

Straight GNR, single species (one organism), polar flagellum, ubiquitous natural habitat in soil and fresh water, oxidase positive, glucose fermenter, Lysine/Ornithine/Arginine all postive

Answer 27

Plesiomonas shigelloides

Question 28

Cause gastroenteritis (mild, chronic, or invasive), extraintestinal infections

Answer 28

P. shigelloides

Question 29

Isolation of P. shigelloides

Answer 29

SBA or MAC (enteric media)

Question 30

curved or S-shaped, seagull wing GNRs, motil by polar flagellum, microaerophilic and capnophilic (37-42’C), normal habitats in GI tracts of poultry, dogs, cats, sheep, cattle, and human; zoonotic (animal to human)

Answer 30

Campylobacter species

Question 31

cause gastroenteritis (C. jejuni), transmitted by contaminated food, self limiting (similar to acute appendicitis), late summer/early fall occurance, most common enteric pathogen

Answer 31

Campylobacter spp

Question 32

Cause Febrile Systemic Disease (Guillain-Barre’ Syndrome) and periodontal disease

Answer 32

Campylobacter

Question 33

Methods to isolate and identify campylobacter

Answer 33

Selective blood based media (Campy-CVA) or charcoal based (CSM); incubate at 42’C, 5% O2, 10% CO2, 85% N for 48 hours

Question 34

Hippurate hydrolysis positive, oxidase pos, catalase pos, curved GNR

Answer 34

Campylobacter

Question 35

spiral shaped GNR, natural habitat is human gastric mucosa (Dr. Barry Marshall’s experiment)

Answer 35

Helicobacter pylori

Question 36

causes gastric and duodenal ulcers, peptic ulcer disease, and gastric cancer, rarely found in stool specimens

Answer 36

Helicobacter pylori

Question 37

diagnosed by Antigen detection, biopsy, urease testing, brucella agar with 5% horse blood, and ELISA tests for IgG

Answer 37

Helicobacter pylori