Diseases of Digestive System

Question 1

Peptic Ulcer

Answer 1

Major Symptoms: Abdominal pain
Organism: Helicobacter pylori
Pathogen: Bacteria gram -
Transmission: Fecal-oral 
Key: relieved by food is duodenal; exacerbated by food is gastric

Question 2

Cholera (bacterial gastroenteritis)

Answer 2

Major Symptoms: Rice water stool
Organism: vibrio cholerae
Pathogen: bacteria gram -
Transmission: fecal-oral, contaminated food & water
Key: freshwater, MC Vibrio to infect humans

Question 3

Shigellosis (bacterial gastroenteritis)

Answer 3

Major Symptoms: purulent bloody stools
Organism: Shigella sonnei, S. flexneri, S. dysenteriae, S. boydii
Pathogen: Bacteria gram -
Transmission: fecal-oral, hands, cold foods & salads
Key: aka Bacillary dysentery; Shiga toxin; in US, S. sonnei (2/3), S. flexneri (1/3)

Question 4

Traveler’s Diarrhea (bacterial gastroenteritis)

Answer 4

Major Symptoms:
Organism: Escherichia coli O157:H7; Norovirus
Pathogen: bacteria gram -
Transmission: fecal-oral, undercooked beef or unpasteurized milk/fruit juice
Key: MC cause of GI infection

Question 5

Campylobacter Diarrhea (bacteria gastroenteritis)

Answer 5

Major Symptoms: 10+/day x 7-10 days
Organism: Campylobacter jejuni
Pathogen: Bacteria gram -
Transmission: MC poultry
Key: MC cause of bacterial gastroenteritis in the US

Question 6

Pseudomembranous colitis (bacterial gastroenteritis)

Answer 6

Major Symptoms: formation of pseudomembranes
Organism: Clostridium difficile
Pathogen: bacteria gram +
Transmission: Extremely common opportunist after taking antimicrobials; common nosocomial infection
Key: life threatening peritonitis; take probiotics w/antibiotics

Question 7

Salmonellosis: Salmonella food poisoning (acute bacterial gastroenteritis)

Answer 7

Major Symptoms: nonbloody diarrhea
Organism: Salmonella enterica enteritidis, S. enterica typhimurium
Pathogen: Bacterial gram -
Transmission: eggs
Key: also associated with reptiles (turtles

Question 8

Salmonellosis: Typhoid Fever (enteric fever)

Answer 8

Major Symptoms: peritonitis
Organism: Salmonella enterica typhi, S. enterica paratyphi
Pathogen: bacteria gram -
Transmission: contaminated food or water
Key: Typhoid Mary

Question 9

Staphylococcal Food Poisoning

Answer 9

Major Symptoms: N/V, diarrhea, cramping
Organism: Staphylococcus aureus
Pathogen: bacteria gram +
Transmission: contaminated food
Key: Homemade thing that don't require cooking

Question 10

Clostridial Food Poisoning

Answer 10

Major Symptoms: NO fever, or N/V
Organism: Clostridium perfringens
Pathogen: bacteria gram +
Transmission: contaminated meat
Key: fairly benign,

Question 11

Yersinia Food Poisoning

Answer 11

Major Symptoms: sometimes mimics appendicitis
Organism: Yersina enterocolitica
Pathogen: Bacteria gram -
Transmission: contaminated pork
Key: infect kids

Question 12

Bacillus cereus food poisoning

Answer 12

Major Symptoms: mild illness
Organism: Bacillus cereus
Pathogen: bacteria gram +
Transmission: consumption of rice dishes cooked and held at warm temp for hours
Key: aka Fried rice syndrome

Question 13

Oral Herpes

Answer 13

Major Symptoms: cold sores
Organism: (HHV-1) sometimes HHV-2
Pathogen: DNA
Transmission: close contact with active lesions
Key: latent virus - trigeminal ganglia

Question 14

Mumps

Answer 14

Major Symptoms: paotitis - paotid salivary glands; testicular swelling in boys - orchitis
Organism: mumps virus (Rubulavirus)
Pathogen: RNA
Transmission: Respiratory secretions
Key: vaccine has almost eradicated mumps in the industrialized world

Question 15

Viral Gastroenteritis

Answer 15

Major Symptoms:
Organism: Norovirus (Calicivirus), Astrovirus, Rotavirus
Pathogen: RNA
Transmission: Fecal-oral, food - oysters
Key: Norovirus - 90% of viral gastroenteritis, #1 cause of foodborne illness in US emerging disease; Astrovirus - no vomiting; Rotavirus - MC cause of infantile gastroenteritis

Question 16

Hepatitis A

Answer 16

Major Symptoms: Jaundice
Organism: Hepatitis A virus (HAV)
Pathogen: RNA
Transmission: fecal-oral
Key: aka infectious hepatitis; resistant to common household disinfectants

Question 17

Hepatitis B

Answer 17

Major Symptoms: Jaundice, associated with liver cancer
Organism: Hepatitis B virus (HBV)
Pathogen: DNA
Transmission: Blood, Bonking, Babies
Key: Coinfection with Hepatits D virus increases risk of permanent liver damage

Question 18

Hepatitis C

Answer 18

Major Symptoms: Chronic infection with few if any symp
Organism: hepatitis C virus (HCV)
Pathogen: RNA
Transmission: Needles, organ transplants, blood, sex
Key: Most non-A, non-B hepatitis in the US

Question 19

Hepatitis D

Answer 19

Major Symptoms: Jaundice, plays a role in triggering liver cancer
Organism: Hepatitis D virus (HDV)
Pathogen: RNA
Transmission: bodily fluids, needles
Key: Needs HBV coninfection, satellite virus

Question 20

Hepatitis E

Answer 20

Major Symptoms: fatal in 20% of pregnant women
Organism: Hepatitis E virus (HEV)
Pathogen: RNA
Transmission: fecal-oral, seafood, pigs, cows, unclean water
Key: aka Enteric hepatitis

Question 21

Giardiasis

Answer 21

Major Symptoms: rotten egg smelling stools
Organism: Giardia intestinalis (G. lamblia)
Pathogen: Protozoa
Transmission: ingesting cysts in contaminated water
Key: aka Beaver fever, common waterborne gastrointestinal disease in the US

Question 22

Crytosporidiosis

Answer 22

Major Symptoms: 
Organism: Cryptosporidium parvum
Pathogen: protozoa
Transmission: drinking contaminated water; fecal-oral
Key: aka Crytosporidium enteritis

Question 23

Amebiasis

Answer 23

Major Symptoms: luminal amebiasis is asymptomatic, invasive amebic dysentery causes severe diarhea, colitis appendicitis, invasive extraintestinal amebiasis causes necrotic lesions in various organs
Organism: Entamoeba histolytica
Pathogen: Protozoa
Transmission: Contaminated food or water, hands, or oral-anal intercourse
Key: 90% of cases are luminal amobiasis

Question 24

Cyclosporiasis

Answer 24

Major Symptoms: 
Organism:Cyclospora cayetanensis
Pathogen: Protozoa
Transmission: raspberries from south/central America
Key: emerging disease

Question 25

Tapeworm Infestations

Answer 25

Major Symptoms/Organism: Taenia saginata (beef) & Taenia solium (pork)Most asympotmatic, weight loss consumption of cysts, proglottids (tapeworm segments); Diphyllobothrium latum, 80% asymptomatic, wight loss, megaloblastic anemia, consumption of undercooked or raw fish, aka diphyllobothriasis; Echinococcus granulosus, consumption of food or water from dog feces canine tapeworm
Pathogen: helminth (cestode)

Question 26

Ascariasis

Answer 26

Major Symptoms: most asymptomatic
Organism: Ascaris lumbricoides
Pathogen: Helminth (nematode)
Transmission: Eggs are ingested in water or on vegetables
Key: MC nematode infection of humans worldwide

Question 27

Hookworm Infections

Answer 27

Major Symptoms: ground itch, chronic anemia, iron & protein deficiencies
Organism: Necator americanus, Ancylostoma duodenale
Pathogen: Helminth (nematode)
Transmission: Larvae penetrate the skin, usually the foot
Key: 2nd MC nematode affecting humans worldwide

Question 28

Pinworm Infestations

Answer 28

Major Symptoms: Intense perianal itching (esp at night)
Organism: Enterobius vermicularis
Pathogen: Helminth (nematode)
Transmission: at night, easily spread on bedding, from person-person after scratching
Key: MC parasitic worm in the US

Question 29

Dracunculiasis

Answer 29

Major Symptoms: worm forms a blister, generally on the foot
Organism: Dracunculus medinensis
Pathogen: Helminth (nematode)
Transmission: Ingesting water containing infected copepods
Key: Guinea worm disease, treatment was winding the worm out on a stick

Question 30

Trichinosis

Answer 30

Major Symptoms: asymptomatic, muscle pain and weakness
Organism: Trichinella spiralis
Pathogen: Helminth (nematode)
Transmission: Ingesting undercooked pork containing cysts
Key: Trichinellosis: NOT common in US