VIBRIO AND OTHER GRAM-NEGATIVE BACILLI

VIBRIO

Although they still infect your gastrointestinal tract, they

are not considered as gram-negative enteric bacilli.

o O1

o O139

Toxigenic Vibrio cholerae is divided into 2 epidemic

serotypes:

(O1)

(o Classical Vibrio cholerae

o El tor)

(____) Divided into 2 biotypes based on biochemical

reactions

o Ogawa

o Inaba

o Hikojima

• antigenic differences

• biochemical reactions

Each O1 biotype can have 3 serotypes (based on

antigenic differences) which are divided into ribotypes:

-(_______)

-(________)

-(________)

• Based on (_______)

• Based on (_______)

• Ogawa à containing A & B antigens

• Inaba à containing A & C antigens

• Hikojima à containing A, B, & C antigens

• Vibrio cholerae / Classical

• Vibrio el tor

BASED ON ANTIGENIC DIFFERENCES

BASED ON BIOCHEMICAL REACTIONS

(-, +) (-, +) (+ (sensitive) -(resistant) (+, -) () () () () ()

BIOCHEMICAL DIFFERENTIATION

OF THE 2 BIOTYPES

	Classical	El tor
Voges Proskauer at 22oC	(____)	(_____)
Chicken erythrocyte agglutination	(_____)	(_____)

Polymyxin B sensitivity (50 IU)	(_____)	(_______)
Group IV Cholera phage sensitivity	(_______)	(______)

(Gram-negative (-) (Oxidase positive (+) (Comma-shaped) (monotrichous)) (pH 7) (9.5) (acid slant/acid butt, no gas, no H2S) (Ferments lactose slowly) (String test positive)

CHARACTERISTICS OF VIBRIO

• (____________)

• (___________)

• (________)

• Motile (single thick polar flagellum - (_______))

• Grow best at pH (___) but can tolerate alkaline conditions

  to pH (_____)

• TSI: Carbohydrate fermentation with acid but no gas (_________)

• (_____________)

• (____________) - only 1 gram-negative bacilli

  positive for string test (Klebsiella pneumoniae)

(Endotoxin) (Enterotoxin

(Choleragen)) (A1) (Na, H2O, Cl, K, HCO3) (B) (adenylate cyclase) (Flagella) (Mucinase) (O) (H)

DETERMINANTS OF PATHOGENICITY

(________)	Caused baby gram-negative bacteria
(________)	Responsible for diarrhea in vibrio; Has subunits A (A1 & A2) & B (____) - Increases the cAMP à loss of cell nutrients (___, ____, ___, ___, ____) / excretion of H2O and electrolytes à causing diarrhea (_____) - Attaches to the mucosal surface; Allows entry of subunit A into plasma membrane à Increased (____________) activity
(________)	Acts as an adhesive & binds the bacteria to cellular surfaces

(________)	Enzyme that destroys mucin in intestinal tract; Enables organism to adhere to the cells of the brush border of the gut or intestinal tract by dissolving the protective glycoprotein coating the intestinal cells

ANTIGENIC STRUCTURE

(___)	Somatic antigens
(____)	Flagellar antigens

(10M bacilli (106 – 1011 CFU) (aquatic environment) (Bile salts, organic acids,) (Only humans) (Houseflies and other insects) (4F’s) ()

CLINICAL MANIFESTATION: CHOLERA

Infecting dose:	(_________)
High dosage:	Series of changes as it moves from (_________) to intestine (temp) Acidic environment of the stomach HCl Intestinal environment (_________________) complement inhibit bacteria growth • Must penetrate mucosal lining of intestinal epithelial cells

TRANSMISSION:

Reservoirs:	(________)
Carriers:	(________)
MOT:	Bacterium transmitted through contaminated (____) (humans to humans) and via contaminated water and food

(ingested) (stomach acid, large dose) (small intestine and

adhere to mucosa) (severe loss of fluids) (dehydration and electrolyte) (ingestion) (stomach’s acid (HCl)) (resistant bacteria) (small intestine) (flagella and mucinase) (bacteria) (dehydration &↓electrolytes)

(rice water stools) (rapid dehydration) (alkaline pH)

PATHOGENESIS OF CHOLERA

1	V. cholerae is (_______)
2	V. cholerae sensitive to (________) needed to cause disease in healthy host
3	Surviving organisms move to (_______&_______)

4	The survival in small intestine depends on attachment, motility, production of mucinase (In the intestine, they produce the toxin, e.g. enterotoxin → causing (_________) → (____________) imbalance) Bacteria enters body through (______) → some bacteria are killed by (___________), only (_________) survive → bacteria proceed to infect (________) → (____________) helps bacteria adhere to cells in small intestine → enterotoxin is produced by (______) → results to diarrhea → diarrhea proceeds to cause severe loss of fluids in infected individuals (___________)
	↑cAMP causes ↑ in fluid secretion; ions follow fluids out
	Massive volumes of watery diarrhea (__________________) (___________)

	Organism is sensitive to stomach acid therefore those with (_______) in the stomach & intestine appear to be more easily infected

(2-3 days; may be hours or a few

days) (Mild diarrhea) (Mucus and intestinal tissue) (Muscle cramps) (Scaphoid abdomen) (Vomiting) (Loss of skin turgor) (Weak pulse) (Choleraic facies) (Cholera cot)

SYMPTOMS OF CHOLERA

	Incubation period: (_______________)
	(______) à sudden severe diarrhea (1L/hr)
	(_____&____) visible in feces

	(_________)
	(________)
	(__________)

	(_________)
	(_________)
	(_________)

	(________)

(CHOLERAIC FACIES) (severe dehydration) (CHOLERA COT)

Tellurite Taurocholate Gelatin Agar (TTGA)

• Thiosulfate Citrate Bile Salt Sucrose Agar (TCBS)

(________________)

• Washerwoman’s hand appearance

• Sunken eyeballs

• Due to (__________)

(________________)

• Used by patients with

cholera

• Hole in the bed with pail

under it

CULTURE MEDIA

TELLURITE TAUROCHOLATE GELATIN AGAR

(TTGA)

• Flattened, transparent colonies surrounded by a cloudy

halo

THIOSULFATE CITRATE BILE SALT

SUCROSE AGAR

• Culture medium of choice

• Flat yellow colonies with opaque center and

transparent periphery

(alkaline peptone) à place in TCBS (Triple Sugar Iron) (Oxidase Test) (String Test)

DIAGNOSIS OF CHOLERA

• (____________) → bacilli exhibit rapid darting

  or shooting motility

• Stool culture → (_____________)

• (______)

• (____________)

TEST RESULTS

(_______)	Lactose fermenter: (______/_____)
(_______)	Positive (+)
(_______)	Positive (+)

(VIBRIO PARAHAEMOLYTICUS) (negative (-)) (monotrichous)) (Hong Kong) (heating at 75C) (Halophilic) (2% NaCl) (4-30 hours, usually 12-24 hours) (Abdominal pain, diarrhea, vomiting, mild fever) (acute gastroenteritis) (Gastroenteritis) (Diarrhea)

(_________________)

CHARACTERISTICS

• Gram-(_______)

• Motile (by means of a single thick polar

  flagellum → (___________)

• (1) (___________) is a halophilic vibrio naturally

  found in the marine environment and seafood

• Commonly associated with seafood

• (________) it is one of the most frequently isolated

  food poisoning organisms

• It can be destroyed by (_______) or above for

  several minutes.

• Distributed worldwide in marine environment

• (_____) (salt loving) à needs (___) for optimum

  growth

SYMPTOMS

• Incubation period: (___________)

• (__________________________)

• Common cause of (___________) associated

  with the consumption of improperly cooked seafood

  (squid, mackerel, sardines, tuna, oysters, clams,

  shrimps, & crabs)

• (____________) is self-limiting lasting about 3 days.

• (_________) is explosive & watery with no blood & mucus,

  accompanied by nausea & vomiting, abdominal

  cramps, & sometimes mild (low) fever

(Consumption of raw/undercooked seafood) (Isolation media) (2%-4% NaCl ) (fluids & electrolytes) (Thiosulfate Citrate Bile Salt Sucrose

Agar) (green) (TCBS)

VIBRIO PARAHAEMOLYTICUS

CLINICAL MANIFESTATION

• Mode of Transmission: (___________________ or cooked food that has been cross-contaminated with bacteria without further

cooking

DIAGNOSIS

• (_________) containing (______) are used

TREATMENT

• Treatment: giving of (__________)

CULTURE MEDIA

(____________________) → differentiated from Vibrio

cholerae by producing large, (__________)

smooth colonies on (______)

(VIBRIO VULNIFICUS) (raw oysters) (warm brackish water, low salt) (bacteremia & liver disease)

(_______________)

CHARACTERISTICS

• Mostly causes outer ear infection (swimming) &

wound infection

• Responsible for rapidly progressive wound

infections after exposure to contaminated

seawater and septicemia after consumption

of raw oysters

• Associated with (__________)

• Common in (_____________________)

• Can also cause (_______________)

(CAMPYLOBACTER) (diarrheal and systemic disease) (comma or S-shaped) (Motile and monotrichous) (25°C) (nalidixic acid) (Microaerophilic)

CHARACTERISTICS OF (_________________)

• Among the most widespread cause infection in the

world

• Cause both (__________________)

• Curved gram-negative (-) rods that

appear as (____________), or

“gull-wing shapes”

• (___________) (single polar flagellum)

• Oxidase positive (+)

• Identified by its failure to grow at (_____)

• Sensitive to (__________)

• (___________) → growing best in 5%

oxygen rather than 20% present in the

atmosphere

• No spore

• No capsule

(Campylobacter jejuni) (42C)

(________) → diarrhea

• Grows well at (_____)

• Major cause of diarrhea in the U.S.A.

CAMPYLOBACTER INTESTINALIS

(______________) → bacteremia

• Does not grow well at 42C

(Lipopolysaccharides (LPS) (endotoxic) (Cytopathic extracellula) (enterotoxins) (milk and meat products) (gastric acid) (10^4) (bloody stools) (bloodstream) (enterotoxin-mediated) (4-8 days) (Acute enteritis) (3 weeks) (Acute colitis) (Diarrhea, malaise, fever, acute abdominal pain) (< 1% C. jejuni)

VIRULENCE FACTORES OF CAMPYLOBACTER

• (__________________) with (________) activity

• (____________) toxins and (____________) →

causes diarrhea and septicemia

PATHOGENESIS & EPIDEMIOLOGY

• Transmission: (Usually fecal-oral) Infection is by oral

route from food, drink, or contact with infected animals

or animal products (_____________))

• Susceptible to (________)

• Infecting dose: about (____) organisms

• Multiply in the small intestine à invade the epithelium

à produce inflammation à cause (___________)

• Occasionally, (_____________) is invaded

• Diarrhea is believed to be (_____________) similar

to Cholera.

SYMPTOMS OF CAMPYLOBACTER

• Incubation period: (__________)

• (__________): 1 week, stools remain positive for (_______)

• (___________): inflammation of colon

• (___, ____, ____, __, ___), usually

self-limiting

• Bacteremia: (__________) (<1% invades bloodstream)

(ENTEROCOLITIS) (1-7 days) (watery, foul-smelling diarrhea) (1-7 days) (SYSTEMIC INFECTIONS) (Skirrow’s medium) (CAMPY-BAP) (CAMPY-CVA) (42C) (5% oxygen & 10% CO2) (Nalidixic acid)

(_______________)

• Commonly due to Campylobacter jejuni

• Incubation period: (_________)

• Begins as (_____________) followed by

bloody stools accompanied by fever abdominal pain after

an incubation period of (_______)

• Production of diarrhea is similar to that of Cholera

(____________________)

LABORATORY DIAGNOSIS

Stool culture on blood agar (remove toxin oxygen radicals) plate containing antibiotics that inhibits most other fecal flora	(_______)	Vancomycin Trimethoprim Polymyxin
	(_______)	Vancomycin Trimethoprim Polymyxin Amphotericin B Cephalothin
	(________)	Vancomycin Cefoperazone Amphotericin B

Plate incubated at (____) in a microaerophilic atmosphere

with (_____________)

Sensitive to (____________)

(flat, droplet-like, glistening)

COLONIES OF CAMPYLOBACTER JEJUNI

• Colonies are (________________)

and tend to spread along the direction of

the streak on moist agar

(HELICOBACTER PYLORI) (Curved bacilli; lophotrichous) (Campylobacter pylori) (Barry Marshall and Robin Warren) (antra gastritis, gastric ulcers, and

gastric carcinoma) (negative, curved rod) (corkscrew motion) (amino acids and fatty

acids) (10% CO2 and 5% O2) (Urease positive (+)) (Catalase positive (+)) (Oxidase positive) (37C) (Urease) (Motility) (Mucinase) (Adherence factor) (Flagella)

CHARACTERISTICS OF (______________)

• (_________________) flagella

• Former name: (____________) due to morphology

• Founded by (___________________)

• Is the prototype organism in this group

• It is associated with (_______________)

IMPORTANT PROPERTIES

• Gram-(_______________)

• Very motile → (______________)

• Fastidious, microaerophilic, use (________________) rather than carbohydrates to obtain energy,

needs (______________)

• (___________) like Proteus à urease breath test

• (_____________) à Produce catalase

• (_____________)

• Grow at (__________), not 25C or 42C

VIRULENCE FACTORS

(______)
	allows the organism to pass through the mucous layer
(_______)	anchors bacteria at the intracellular junction of enteric cells

(_________)	helps in its mobility in the gastric mucosa

(mucus layer of stomach) (Ammonia) (Gastric ulceration (or Peptic ulcers)) (mucus-secreting) (inflammatory

response) (mucosa ) (protective

mucus) (gastric or duodenal) (60 yrs) (gastric mucosa) (feces & dental

plaque) (Toxins and LPS) (Gastritis & duodenal ulcer) (bleeding) () () () () () () () () () () () () () ()

PATHOGENSIS & EPIDEMIOLOGY

1 H. pylori penetrates the (_________) and

adheres to the surface of gastric mucosal epithelial

cells

2 (________) is produced (urease hydrolyzes urea à

ammonia & CO2) which neutralizes the gastric acid

3 H. pylori proliferates, and migrates, and finally causes

infection

4 (________________) is developed by

the destruction of the mucosa, inflammation, and

mucosal cell death

Attaches to (_________) cells of the gastric mucosa à

organism’s urease hydrolyzes urea to ammonia & CO2 à

large amount of ammonia coupled with (_________) à damage to the (_____) à loss of (________) coating à (__________) ulcer

• 50% adults older than (_______). are infected

• Primary habitat is the human (______)

• Has been occasionally cultured from (________) suggesting fecal-oral transmission

• (_________) may damage mucosal

CLINICAL MANIFESTATIONS

• (___________) are characterized by

recurrent pain in the upper abdomen, frequently

accompanied by (_______) in the gastrointestinal tract

(Gram stain) (H&E

Warthin silver stain

Giemsa stain) (cephalothi) (Columbia agar) (CAMPY-CVA) (CAMPY-BAP) (a scintillation counter or special spectrophotometer) (Positive (+) (SKIRROW’S MEDIUM)

HELICOBACTER PYLORI

LABORATORY DIAGNOSIS

(_______)	Difficult to observe, rarely done Counterstain: basic fuchsin Specimen: biopsy specimen of gastric mucosa
(________)	Usually done
Culture	Can be cultured as Campylobacter à enriched medium with blood, hemin, charcoal (protect the organism from oxygen free radicals) Can be cultured on: • Skirrow’s medium without (________) • (_________) • (________) • (__________) cannot be used because it contains cephalothin

Endoscopy and biopsy	(______)
Urea breath test	Urease positive (+) within 1-2 hours • Samples of breath air is collected by having the patient blow into a tube before and 30 minus after ingestion of 13C-labeled urea, rapid, non-invasive, for assessing response 4-8 weeks post therapy • Expensive but not invasive • Radiolabelled urea is ingested, if the organism is present, radiolabelled CO2 is evolved and the radioactivity is detected in the breath by using a (_______________)
Catalase & Oxidase test	(_________)

(_________) → small, translucent to pale graying

colonies