Gastrointestinal

Question 1

Viral GI- Eti

Answer 1

Rotovirus- young children- vaccine available, fecal- oral route w/in 72 hrs of exposure
Norovirus- adults, w/in 48 hrs- resistant to chlorination
Astrovirus- kids in developing
Enteric Adenovirus- resp infection followed by diarrhea

Question 2

Viral GI- Sx

Answer 2

Roto- Damage to sm. bowel epithelium, damage brush border-.prolong sx
Noro- acute explosive vomiting and diarrhea- small bowel- fever, HA & malaise
Astro- N/v less common
Enteric Adeno- Resp sx proceed GI

Question 3

Viral GI- Dx

Answer 3

PCR if needed, self-limiting

Question 4

Viral GI- Tx

Answer 4

Self limiting- rehydration & oral nutrition

Question 5

Typhoid fever- Eti

Answer 5

Salmonella Typhi & parathyphi. Small intestine. colonizes epi cells-> tissue damage-> inflame. diarrhea. Person to person only! 1-2 wk incubation

Question 6

Typhoid fever- Sx

Answer 6

Pea soup diarrhea, rose spots, fever- rises in stepladder, bradycardia, HSM, LAD, delirium, HA

Question 7

Typhoid fever- Dx

Answer 7

Blood culture- stool unreliable. Presence of rose spots

Question 8

Typhoid fever- Tx

Answer 8

Quinalones or 3rd g cephalosporins
Corticosteroids
Cholecystectomy if not cleared

Question 9

Cholera- Eti

Answer 9

Vibrio cholerae. Coastal salt water and estuaries- Asia, Africa & Gulf coast. Contaminated seafood, fecal/oral and travel to endemic areas. 70% mortality if untreated.

Question 10

Cholera- Sx

Answer 10

Rice water stools, profuse, watery diarrhea-> vomiting-> rapid dehydration and hypovolemic shock + death. Sm bowel.

Question 11

Cholera- Dx

Answer 11

Dark field microscopy on wet mount

Question 12

Cholera- Tx

Answer 12

Oral rehydration salts- Na, K, Cl, Citrate, Glucose. Tetracycline

Question 13

Giardia- Eti

Answer 13

Most common parasite in US. Fecal-oral- camping, well water. Cysts & trophozoites. Sm bowel-> trophozoites attach to duodenum and jejunum.

Question 14

Giardia- Sx

Answer 14

Foul, fatty diarrhea, bloating, flatus. Upper GI sx- fever uncommon, sulfurous belching

Question 15

Giardia- Dx

Answer 15

cysts or trophozoites in stool

Question 16

Giardia- Tx

Answer 16

Metronidazole, avoid lactose, treating carriers can prevent outbreaks

Question 17

Giardia- Prevention

Answer 17

Boil water, iodine based tx effective

Question 18

Shigella- Eti

Answer 18

S. Sonni (common) S. dysenteria (shiva toxin- severe & rare) Food, water, person transmission. Resistant to stomach acid.

Question 19

Shigella- Sx

Answer 19

Fever, malaise, abd pain, watery stool, respiratory symptoms, seizures. May turn bloody, mucus/ pus

Question 20

Shigella- Complications

Answer 20

Toxic megacolon- toxic paralysis of colon, trapping flatus. Hemolytic-uremic syndrome, Reactive arthritis. Most common in <5.

Question 21

Shigella- Tx

Answer 21

Self limiting- hydration & avoid anti motility agents. Cipro if needed.

Question 22

Shigella- Dx

Answer 22

Fecal leukocytosis, culture

Question 23

Salmonella- Eti

Answer 23

Highest food borne pathogen in US. Raw poultry, petting zoos, reptiles, produce treated with feces. Small intestine

Question 24

Salmonella- Sx

Answer 24

N/V-> D/cramps. May be bloody. Fever, RLQ tenderness, self limiting

Question 25

Salmonella- complications

Answer 25

bacteremia-> meningitis, pulmonary infections, osteomyelitis or reactive arthritis

Question 26

Salmonella- Dx

Answer 26

Stool culture

Question 27

Salmonella- Tx

Answer 27

Hydration- avoid anti motility agents. Quinolones recommended if severe

Question 28

Amebiasis- Eti

Answer 28

Intestinal protozoa- ingestion of cysts through fecal oral route. Human only. Encystation in sm bowel causing tissue distruction -> bloody diarrhea.

Question 29

Amebiasis- Sx

Answer 29

90% asymptomatic. Subacute onset- diarrhea, abd pain, fever, tenesmus- stool has little fecal matter- mostly blood/ mucus. Flask shaped amebic ulcers. Liver abscesses.

Question 30

Amebiasis- Dx

Answer 30

ID org. in stool or antigen assay

Question 31

Amebiasis- Tx

Answer 31

Metronidazole, dont drain abscess, Diloxanide for cysts

Question 32

Clostridium difficile- Eti

Answer 32

Abx associated colitis via fecal oral route. Exotoxins lead to inflammation and bacteria. 1) Alteration in gut flora 2) Acqusition and germination of spores 3) C. diff overgrowth 4) toxin production. Toxin A- damage mucosa Toxin B- hemorrhage, inflammation & cellular necrosis.

Question 33

C. diff Sx

Answer 33

Watery to mucoid diarrhea, abd. pain, low grade fever, sm. amounts of blood, toxic megacolon & perforation.

Question 34

C. diff- Dx

Answer 34

Enzyme immunoassay with PCR. Caused by fluoroquinolones and many other abx.

Question 35

C. diff Tx

Answer 35

Metronidazole for mild, vanco for severe

Question 36

Campylobacter- Eti

Answer 36

Contaminated poultry- common in kids & teens. 2nd most prevalent food bourne disease.

Question 37

Campylobacter- Sx

Answer 37

Fever, myalgia, malaise, abd pain, HA followed by profuse watery to bloody diarrhea.

Question 38

Campylobacter- Dx

Answer 38

Blood or stool culture

Question 39

Campylobacter- Complications

Answer 39

Hemolytic uremic syndrome, reactive arthritis, Gullian-Barre syndrome

Question 40

Campylobacter-Tx

Answer 40

Erythromycin- wihtin 3 days. Qunialones later in illness. | Only if >1 wk, pregnant, immunocompromised, dysentery, fever

Question 41

Hemolytic Uremic Syndrome

Answer 41

Simultaneous occurrence of hemolytic anemia, thrombocytopenia & acute kidney injury caused by abx

Question 42

Reactive arthritis

Answer 42

arthritis, urethritis & conjunctivitis

Question 43

Guillain Barre Syndrome

Answer 43

Inflammatory auto immune condition- causes body not to recognize self

Question 44

E. coli EHEC- Eti

Answer 44

Produces shiga toxin- adhering to small and large bowel. Reservoir of ruminant animals- undercooked near, milk, petting zoos. Low innoculum.

Question 45

EHEC- Sx

Answer 45

3-5 day incubation. Colonizes colon-> colitis. Grossly bloody diarrhea >90% cases, abd pain, myalgia, NO fever

Question 46

EHEC- Complications

Answer 46

Hemolytic uremic syndrome- young & elderly. 2-8% of cases

Question 47

EHEC- Dx

Answer 47

Not part of routine culture screening- specify with lab

Question 48

EHEC- Tx

Answer 48

No abx! Self limiting. Avoid narcotics, anti-motility agents. Replace h20 and lytes

Question 49

Enteroinvasive E.coli- EIEC- Sx

Answer 49

identical to shigellosis- profuse diarrhea, vomiting, malaise, abd cramsp, high fever & chills, within 12-72 hrs of ingestion

Question 50

Enterotoxigenic Ecoli- ETEC

Answer 50

Common cause of travelers diarrhea. Watery diarrhea, bloating, fatigue, cramps- 3-5 days. Bloody & fever uncommon.

Question 51

ETEC- Tx

Answer 51

Only immunocomp- cipro and bismuth. Others bismuth, rehydration, no antidiarrheals

Question 52

B. Cereus- Epi

Answer 52

Abundant in marine environs, soil dwelling- food contaminant- heat resistant spores

Question 53

B. Cereus- sx

Answer 53

Food poisoning- 8-16 hrs following ingestion- copious diarrhea

Question 54

B. Cereus- Dx

Answer 54

Stool culture

Question 55

B. Cereus- Tx

Answer 55

Hydration therapy