Curved and Spiral- Shaped gram negative rods

Vibrio, Aeromonas and Campylobacter sp. are often cultured where?

From gastrointestinal specimens.

Vibrio, Aeromonas and Campylobacter sp. are responsible for what?

Responsible for large epidemics, and pandemics as well as gastrointestinal ulcers.

What does Vibrio mean?

Vibrate

Genu vibrio gen characteristics?

-Gram negative rods with polar, sheathed flagella in broth but peritrichous, unsheathed flagella on solid media

-Rods are "curved" in clinical specimens, ( often referred to as coma shaped) but small, straight rods after culture

What environment does Genus vibrio grow in?

Facultative anaerobe

Is Genus vibrio spore forming?

No

Vibrio species biochemicals?

-Most are oxidase positive and able to reduce nitrates to nitrites

All species of vibrio is susceptible to?

Vibriostatic compound O/129

What does vibrio exhibit when colonies are mixed with sodium desoxycholate?

Mucoid stringing reaction

Most vibrio are?

Halophilic (salt-loving)

Some strains of vibrio are serotyped because they have?

O and H antigens

Where can vibrio be isolated from?

Variety of clinical specimens, including feces, wound, and blood

Vibrio is present on?

Marine animals

What environment is vibrio common in?

Salt water environments

What are the major species of vibrio?

V. cholerae, V. parahaemolyticus, V. vulnificus, and V. alginolyticus

Best indicators of vibrio infection is presence of what recognizing factors?

-Recent consumption of raw seafood (especially oysters)

-Recent immigration or foreign travel

-Gastroenteritis with cholera-like or rice-water stools

-Accidental trauma during contact with fresh or marine water

V. cholerae causes?

Cholera

What is Cholera?

-Usually contracted by drinking contaminated water or eating food washed in contaminated water.

-Eating undercooked sea food and fish are the most common food sources

V. cholera can remain as?

A free living organism among plankton, algae, crustaceans and fish provided temperature, saline level and nutrients remain adequate

V. cholerae clinical infection?

-Acute diarrheal disease

-Spread through contaminated water, but also improperly preserved foods, including fish and seafood, milk, ice cream, and unpreserved meat

-"Rice Water" stools

Rice water stool is caused by? death?

Caused by cholera toxin or choleragen

Dehydration is usual cause of death

V. cholerae is more often seen after?

–Often see epidemics following natural disasters

Clues of Identification of Vibrio cholera?

-Short motile, common shaped gram negative bacteria

-Oxidase positive

-Salt loving

-Nitrate positive

-Yellow colonies on Thiosulfate citrate bile sucrose agar

( TCBS)

-Will demonstrate the string reaction with mixed with sodium desoxylate medium

-Usually identified by serology methods

V. parahaemolyticus is?

Second most common Vibrio species involved in gastroenteritis

“Summer diarrhea” in Japan

Most cases of V. parahaemolyticus are?

Most cases traced to recent consumption of raw, improperly cooked, or recontaminated seafood, especially oysters

V. parahaemolyticus infections can form after?

Exposure of a wound to contaminated water.

How long does V. parahaemolyticus run its course?

3 days

Symptoms for V. parahaemolyticus?

Gastrointestinal symptoms are generally self-limiting; watery diarrhea, moderate cramps or vomiting

V. vulnificus is found where?

-Found in marine environments along all coasts in the U.S.

Vibrio Vulnificus two categories of infections?

Primary septicemia following consumption of contaminated shellfish, especially raw oysters; patients with liver dysfunction that results in increased levels of iron are predisposed

Wound infections following traumatic aquatic wound

Aeromonas hydrophilia general characteristics?

Ubiquitous oxidase-positive, glucose-fermenting, motile, not curved gram-negative rods widely distributed in fresh and salt water environments

Aeromonas hydrophilia isolated from?

Produce and meat sources

Aeromonas gastroenteritis results from?

Consumption of contaminated seafood, especially raw oysters or clams; illness usually self-limiting, except in very young and old populations

Wound infections from A. hydrophilia?

Resulting from traumatic water-related wound

A. hydrophilia can grow on?

MAC

Campylobacter characteristics?

-Non-spore-forming, curved, gram-negative rods, showing an S-shaped ("seagull-wing") appearance

-Exhibit "darting" motility

-Require selective media and microaerophilic environment for growth

C. jejuni is the most common cause of?

Bacterial gastroenteritis

Campylobacter infections attribute to?

Direct contact with animals and indirectly through consumption of contaminated water and dairy products and improperly cooked poultry

How can campylobacter be transmitted?

Sexually

Campylobacter on gram stain?

Curved, gram-negative rods appearing as long spirals, S shapes, or seagull-wing shapes; stains poorly, so safranin counterstaining should be extended to 2 to 3 minutes

Campylobacter can grow in what environment?

Cultured on Campy plates at 42 degrees C in microaerophilic and capnophilic environment

What characteristic of campylobacter? Biochemicals?

Darting motility in hanging drop, oxidase positive, and catalase positive

Helicobacter pylori is strongly associated with?

Gastric and duodenal ulcers; low grade inflammatory process

Helicobacter pylori organisms do not?

Invade the gastric epithelium, but the host immune antibody response causes inflammation

Helicobacter pylori biochemicals

Can be cultured, but it is so strongly urease positive that presumptive identification often made from biopsy specimen by testing for urease production

A test that can be done to confirm Helicobactor pylori?

■14C-labeled urea breath test

Chromobacterium violaceum characteristics?

Colonies will grow on Sheep blood, chocolate and MacConkey

Demonstrates a distinct violet color

Smells of ammonium cyanide which is similar to almonds.

When you encounter a pigmented strain you can presumptively ID the organism.