Gram negative rods in GI tract

Question 1

What species of salmonella infects humans?

Answer 1

Salmonella enterica

Question 2

If a bacteria is a Gram negative rod, a facultative anaerobe that is motile, is mainly aquired by humans by eating contaminated food or water esp poultry or eggs, causes Gastroenteritis or Typhoid and Enteric fevers or Bacteremia what is it?

Answer 2

Salmonella

Question 3

Who does bacteremia associated with Salmonella mainly target? What happens to them?

Answer 3

Mainly patients with preexisting chronic diseases or children with gastroenteritis, it leads to infection of many organs, osteomyelitis, pneumonia and miningitis are the most common

Question 4

What is the most common form of Slamonella disease in the US, how long does it incubate?

Answer 4

12-48 hour incubation, GASTROENTERITIS starts with nausea vomiting and goes to abdominal pain, it is usually self limiting within a few days

Question 5

What species of salmonella causes Bacteremia generally?

Answer 5

S. cholerasuis

Question 6

Does salmonella form lactose fermenting colonies on MacConkey agar?

Answer 6

no

the colonies are colorless

Question 7

Are there vaccines available for Salmonella?

Answer 7

not all strains but there are vaccines for typhoid fever

Question 8

If a bacteria is a gram negative rod that is a non motile facultative anaerobe that has only a human reservoir, transmitted by fecal oral route has a very low LD50 about 100 organisms are SUFFICIENT to cause disease, usually foodborne outbreaks common in children and day cares what is it likely to be?

Answer 8

Shigella

Question 9

Do all species of shigella produce toxin?

Answer 9

No but those that do usually cause more severe disease

Question 10

Where does shigella colonize in disease? how does it get there?

Answer 10

Limited to GI tract

Shigella invades mucosal cells of the distal ileum an dcolon, and causes inflammation and ulceration.

Question 11

Describe the Enterocolitis caused by shigella?

Answer 11

its called shigellosis and has incubation period of 1-4 days, causes FEVER and ABDOMINAL cramps first, then watery diarreha THEN bloody diarrhea that also has mucous in it. Severity depends on species and age of patient

Question 12

Is there a vaccine for shigella?

Answer 12

no

Question 13

If a bacteria is a gram negative rod that is encapsulated found in RESPIRATORY TRACT of some healthy people, usually causes problems for at risk people, has an anti-phagocytic capsule causes THICK BLOODY SPUTUM, can cause complicated UTIs is UREASE POSITIVE AND LACTOSE FERMENTING POSITIVE and does NOT have a vaccine what is it?

Answer 13

Klebsiella pneumoniae

Question 14

If a gram negative rod “swarms” on agar plates, is found in soil and water and is part of normal flora of colon, a common cause of UTIs, can also cause pneumonia and wound infections does NOT FERMENT LACTOSE and is UREASE POSITIVE and does NOT HAVE A VACCINE what is it?

Answer 14

Proteus

examples are P. vulgaris and P.mirabellis

Question 15

If a gram negative rod is comma shaped, a facultative anaerobe, comes from food/water contaminated with FECES, can be excreted asymptomatically, happens in overcrowded poorly sanitized places, requires TONS of organisms to cause an infection, secretes a mucinase that lets them adhere to cells in brush border of small intestine, secretes ENTEROTOXIN causing fluid loss, is LYSOGENIC, causes LARGE VOLUMES OF WATERY DIARRHEA (rice stool) and main risk is dehydration what is it?

Answer 15

Vibrio cholerae

Question 16

are there vaccines for cholera?

Answer 16

yes there are 2 but they are not used in the US

Question 17

If a gram negative rod is comma or S shaped, Microaerophilic, grows well at 42C, comes from food/water contaminated by animal feces is the MAJOR cause of diarrhea in the US, causes gastroenteritis can invade, causes smelly diarrhea then bloody stools with white blood cells usually self limited OXIDASE POSITIVE and UREASE NEGATIVE what is it??

Answer 17

Campylobacter jejuni

Question 18

Is there a vaccine for Campylobacter jejuni?

Answer 18

no

Question 19

If a rod is curved gram negative, exists in the stomach of many people probably has person to person transmission, it attaches to mucous secreting cells of gastric mucosa, PRODUCES UREASE WHICH PRODUCES AMMONIA. Can cause peptic ulcers or gastritis and is associated with gastric cancers.

Answer 19

Helicobacter pylori

Question 20

If a bacteria is a gram negative Pleomorphic rod that has v little endotoxin, sometimes a capsule, is ANAEROBIC, stimulated by BILE, part of normal flora in GI respiratory and genital tract, opportunistic in parts of body its not supposed to be in. Can cuase skin infections bacteremia, gastroenteritis, what is it?.

Answer 20

Bacteroides an example is B. Fragilis