GI Infections

Question 1

Cystic hepatic lesion with eggshell calcifications
Can have RUQ pain, N/V, hepatomegaly
No fever or diarrhea

Answer 1

Hydatid cyst (Echinoccocus)

Host: dogs

Usually asymptomatic

Question 2

Hepatic abscess, recent bloody diarrhea, travel to Mexico
RUQ pain, fever
Maybe hepatomegaly, leukocytes is, elevated ALKP and transaminases

Answer 2

Amebiasis (entamoeba histolytica)

—> Dysentery (unlike echinococcus which is usually asx)

Question 3

Treatment of large liver cyst due to echinococcus

Answer 3

Aspiration with albenazole

Question 4

Treatment of amebic liver abscess (entamoeba histolytica)

Answer 4

Metronidazole + luminal agent (paromomycin) to prevent spread into colon

DO NOT drain due to risk of spill into peritoneum, unless super big, not improving with tx, imminent rupture etc.

Question 5

How to diagnose amebic liver abscess?

Answer 5

Serologic testing for Entamoeba histolytica!

Stool microscopy is NOT useful since it takes months to form the abscess

Question 6

Reheated rice, 1-6hr after ingestion, vomiting-predominant

Answer 6

Bacillus cereus (preformed enterotoxin)

Question 7

HBsAg

Answer 7

HepB surface antigen

If positive, indicates active infection

Question 8

HBsAb

Answer 8

Antibody to HBsAg

Indicates immunity to HepB

Question 9

HBcAb

Answer 9

Indicates prior or current infection
(+IgM in acute infection and IgG in chronic infection)

Note that this appears earlier than surface Ab (“window period”)

Question 10

What does cryptosporidium parvus do in healthy vs immunocompromised people

Answer 10

Profuse watery (traveler’s) diarrhea if healthy

chronic infection if immunocompromised

Question 11

Large smooth hepatic cyst often with daughter cysts (internal septations)

Answer 11

Echinoccocus

Question 12

Risks for echinoccocus

Answer 12

Dogs that eat sheep innards

Question 13

T solium

Answer 13

PORK
SEIZURES
Cysticercosis

Question 14

Fish tapeworms

Answer 14

Diphyllobothrium latum -> B12 deficiency -> megaloblastic anemia

Question 15

Abd pain, N/V/D
Triad: Myositis, periorbital edema, eosinophilia
Subungual splinter hemorrhages

Answer 15

Trichinellosis

Parasite
From uncooked pork

Question 16

Worm to lungs (nonproductive cough), intestines (asymptomatic), liver (bile duct obstruction)

Answer 16

Ascariasis

Question 17

Retro-orbital pain +systemic sx

+/- hemorrhage in skin or nose

Answer 17

Dengue fever

Question 18

1st week: fever
2nd week: abd pain, salmon-colored rash
3rd week: hepatosplenomegaly, intestinal bleeding/perf

Answer 18

Typhoid fever

Question 19

Treat for acute hepatitis B infection (+ antigen)

Answer 19

HB vaccine + HB IG

Question 20

Sequelae of HepA infection?

Answer 20

Most patients completely recover

Unless preexisting chronic liver dz

Question 21

Fever, leukocytosis, LUQ abd pain
Left pleural effusion with pleuritic chest pain
+/- splenomegaly

Answer 21

Splenic abscess (staph, strep, salmonella)
Often 2/2 infection (eg infective endocarditis, IVDU) with hematogenous spread

Question 22

3 bugs causing bloody diarrhea

Answer 22

E. coli (EHEC producing Shiga-toxin): uncooked beef, cow feces
Shigella
Campylobacter: raw meats

Question 23

Diarrhea from raw/undercooked shellfish

Can can use invasive life-threatening dz in immunocompromised or liver disease

Answer 23

Vibrio vulnificus

Question 24

2 bugs causing diarrhea via preformed toxins

Answer 24

Staph aureus (vomiting-predominant)

B cereus (rice —> diarrhea, abd cramping)