GI Exam 2 (not finished dont download yet)

Question 1

Riovirus Family

lab tests

Answer 1

A Race on the Rio

• NEG** sense _D_S RNA**
• DS! DS! DS! (Only RNA DS in sketchy!)
• NAKED virus
• avg of 11 Segments, 9-12 (B.O.A.R. mnemonic)

Question 2

Rotavirus (a Riovirus)

key facts

Answer 2

A Race on the Rio

• Fecal-oral transmission
• Toxin mediated (NSP4 enterotoxin) secretory diarrhea.
• NSP4 ↑ Cl^- permeability → secretory diarrhea that is explosive and watery (like norovirus, think Rotavirus sounds like rotate propeller).
• Classic outbreaks are in winter!
• Children most at risk (infants, daycare, etc).
• #1 cause of severe diarrhea in young children!

Question 3

Colorado Tick Virus (a Riovirus)

key facts

Answer 3

A Race on the Rio

• Colorado Tick Virus
• Symptoms include myalgia, fever, and vomiting.
• NO rash !!!
• ddx from Rocky Mountain Spotted Fever due to lack of a rash with Colorado Tick Virus.

Question 4

Rotavirus (a Riovirus)

Treatment

Answer 4

A Race on the Rio

Supportive care and oral rehydration

Question 5

Rotavirus (a Riovirus)

Vaccine

Answer 5

A Race on the Rio

• Live attenuated oral vaccine
• 1^st dose given before 3 months of age due to:

1. Decreased efficacy
2. May increase risk of intussusception*

* (stimulation and enlargement of peyers patches → which then act as lead points for the intestine to telescope into itself → can cut off blood supply → and possible bowel perforation.

Question 6

Calicivirus

replication MOA

Answer 6

Cali Sea Cruise

Naked POS** sense _R_NA**

Calici produces one long single protein that is cleaved by viral proteases into smaller active constituents. (like Picornaviruses!!!)

Replicates in the cytoplasm like all POS sense RNA.

Question 7

Calicivirus

signs and symptoms

Answer 7

Cali Sea Cruise

• Most common strain of Calicivirus is NOROVIRUS (Norwalk virus)
• Calici is commonly acquired by people in closed quarters like cruises (90% of all diarrhea outbreaks on cruises!) and day care.
• Also acquired from shellfish or places where food is touched by people (buffets!)
• Explosive diarrhea!!!

Question 8

Adenovirus

lab tests

Answer 8

A Den-O lions

DS DNA

Naked virus (No envelope!)

Question 9

Adenovirus

Source

Answer 9

A Den-O lions

• Transmitted by respiratory droplets and fecal-orally.
• Most at risk are little children**, **military recruits, and public pools.

Question 10

Adenovirus

signs and symptoms

Answer 10

A Den-O lions

3 major disease processes:

1. Tonsillitis (most common cause of infection in adenoids and tonsils).
2. Hemorrhagic cystitis*
3. Viral conjuctivitis aka “Pink Eye“ (common cause)

* DDX BK Virus (a Polyomavirus) which also has hemorrhagic cystitis, but is more common in immunocompromised (transplant pts, or pts with AIDS)

Question 11

Adenovirus

Vaccine

Answer 11

A Den-O lions

Military** recuits get a **live vaccine

Question 12

Entamoeba histolytica

lab tests

Answer 12

Entering the Historical Dig

Flask shaped ulcers along the colon

Bloody stool

Stool O&P (ova and parasite exam) looking for cysts or trophozoites will contain trophozoites that contain endocytosed RBC’s.

Elisa antigen test on stool or serum.

Question 13

Entamoeba histolytica

2 main life cycle stages

Answer 13

Entering the Historical Dig

1. Cyst form is infectious and is ingested from contaminated water. Gay men can get the disease from anal oral transmission.
2. Trophozoite** form invades** the colon, spreads via portal circulation into the liver.

Question 14

Entamoeba histolytica

signs and symptoms

Answer 14

Entering the Historical Dig

• RUQ pain w/ enlarged and tender liver.
• Right lobe is the most commonly involved site of amoebic liver abscesses.
• Puss inside abcess have “anchovy” paste consistency.
• Intestinal amebiasis
• Flask shaped ulcers along the colon.
• Bloody stool

Question 15

Entamoeba histolytica

Treatment

Answer 15

Entering the Historical Dig

Metronidazole

Can be taken with a lumenal agent like:

Paramycin or Iodoquinol

* DDX Entamoeba which you treat without removing surgically vs. Echinococcus which has a liver mass that you do remove surgically.

Question 16

Giardia Lambia

lab tests

Answer 16

Giardia Jungle Ride

Foul smelling Steatorrhea (fatty diarrhea)

Stool O&P (ova and parasite exam) looking for cysts or trophozoites show trophozoites that are flagellated with ventral sucking discs.

Elisa antigen test on stool

Deficient in Vit. A,D,E,K

Question 17

Giardia Lambia

2 main life cycle stages

Answer 17

Giardia Jungle Ride

1. Cysts from feces contaminates water, and infects travelers, backpackers, or campers who drink unfiltered or unpurified water.
2. Trophozoites attach to but do not invade intestinal walls, so only cause diarrhea.

Question 18

Giardia Lambia

Treatment

Answer 18

Giardia Jungle Ride

Metronidazole

Question 19

Giardia Lambia

signs and symptoms

Answer 19

Giardia Jungle Ride

Bloating, flatulence, and foul smelling diarrhea.

Steatorrhea (fatty diarrhea) due to excessive mucous production that impairs the absorption of the intestine (A,D,E,K will be deficient).

Question 20

Cryptosporidium

lab tests

Answer 20

Tales from the crypt

Unicellular partially acid fast.

Under staining looks like amethyst in water.

Cysts contain 4 motile sporozoites.

Profound watery diarrhea.

Question 21

Cryptosporidium

2 main life cycle stages

Answer 21

Tales from the crypt

1. Oocysts are infectious, released fecally, and absorbed orally. Highly resistant to chlorination, but can be removed via filtration.
2. Cysts contain 4 motile sporozoites that will attach to the small intestine wall and cause damage.

Question 22

Cryptosporidium

signs and symptoms

Answer 22

Tales from the crypt

Profound watery diarrhea

* Most common cause of diarrhea in AIDS patients!

Question 23

Cryptosporidium

Treatment

Answer 23

Tales from the crypt

• Nitazocanide tx for immunocompetent
• Spiromycin (not FDA approved in US)(a macrolide antibiotic)
• Supportive care

Question 24

Enterobius vermicularis (pinworms)

Intestinal nematode (round worms)

source / signs and symptoms

Answer 24

Super Worms!!! (In Nematode City)

Female pinworms migrate to the anus and lay eggs → causes itching → fecal oral transmission can reinfect if touch mouth after scratching anus.

Question 25

_**Ancyclostoma duodenale** and **Necator americanus**_ (****_hook_**worms**) **_Intestinal nematode_** **(round worms)** source / signs and symptoms

Answer 25

**_Super Worms!!!_** (**In Nematode City)** * ****_Hook_**worms** found in **rural _southern_ US** * **Walk _barefoot**_ → Enter _****blood**_stream** → **Larvae** go to **_lungs_** → ascend bronchiole tree → get **coughed up** → **swallowed**, then enter and **mature in** the **_intestine_**. (**feet**→blood→lungs→GI) * Pt can develop **severe _iron deficiency anemia_**.

Question 26

**_Ascaris lumbricoides_** (**Giant _large_ worm**) **_Intestinal nematode_** **(round worms)** source / signs and symptoms

Answer 26

**_Super Worms!!!_** (**In Nematode City)** * **_Ingest_ _eggs_** from contaminated **food or water** → migrate to **lungs** **through gut wall** and **blood**stream → come back to **gut** to become **adults** → go into **feces** (**GI**→blood→lungs→GI) * **_Malnutrition_** and **_respiratory_ symptoms** (most likely intestinal nematode to cause resp. sympt.) * **Intestinal obstruction** at **_ileocecal_ valve** (major complication!)

Question 27

**_Enterobius vermicularis_** (****_pin_**worms**) **_Intestinal nematode_** **(round worms)** lab tests / tx

Answer 27

**_Super Worms!!!_** (**In Nematode City)** **_Scotch tape test_** on anus → eggs will stick to tape → visible on **microscope**. **tx** with **Pyrantel **_pam_**oate** and **Al**_bend_**azole**

Question 28

_**Ancyclostoma duodenale** and **Necator americanus**_ (****_hook_**worms**) **_Intestinal nematode_** **(round worms)** lab tests / tx

Answer 28

**_Super Worms!!!_** (**In Nematode City)** * Look for **eggs in stool.** * **_High_ eosinophil count** (**_eosinophilia_**). * **tx** with **Pyrantel **_pam_**oate** and **Al**_bend_**azole**

Question 29

**_Ascaris lumbricoides_** (**Giant _large_ worm**) **_Intestinal nematode_** **(round worms)** lab tests / tx

Answer 29

**_Super Worms!!!_** (**In Nematode City)** * Look for **eggs in stool** * **_High_ eosinophil count** (**_eosinophilia)_**. * **tx** with **Al**_bend_**azole\*** **\***(**Al**_bend_**azole** causes microtubule dysfunction to make worms immobile. **_Dont_** give **microtubule inhibitors** to **pregnant** women. If pregnant **give** **Pyrantel **_pam_**oate**)

Question 30

**_Strondyloides stercoralis_** (**_Thread_ worm**) **_Intestinal nematode_** **(round worms)** source / signs and symptoms

Answer 30

**_Super Worms!!!_** (**In Nematode City)** * Penetrate skin on bottom of **feet** → then goes to **lungs** → then **GI tract** → **_AUTOINFECTION_** of host by **laying _eggs**_ on _**intestinal wall_!** (**feet**→blood→lungs→_**GI**→**GI**→_**_GI._..**) * If **immunocompromised** can **lead to hyper** infection.

Question 31

**_Strondyloides stercoralis_ (_Thread_ worm)** **_Intestinal nematode_** **(round worms)** lab tests / tx

Answer 31

**_Super Worms!!!_** (**In Nematode City)** * **Eggs DONT** **get passed t**o stool so **only _find larvae_** in **stools**. * **_High_ eosinophil count** (**_eosinophilia)_**. * **tx** with **Al**_bend_**azole\*** and ****_Iver_**mectin** **\***(**Al**_bend_**azole** causes microtubule dysfunction to make worms immobile. **_Dont_** give **microtubule inhibitors** to **pregnant** women. If pregnant **give** **Pyrantel **_pam_**oate**)

Question 32

**_Trichinella spiralis_** (**_Trichina_ worm**) **_Intestinal nematode_** **(round worms)** source / signs and symptoms

Answer 32

**_Super Worms!!!_** (**In Nematode City)** * Found in **undercooked meat**, commonly **_pork_** or **_bear_**. * Larvae get into blood → go systemic → form **cysts in _striated muscle_ cells** (**GI**→blood→systemic→**striated muscle cells**) * **Peri**orbital **edema** * Vomiting and fever * **Inflammation** of **muscle** → severe **myalgia**

Question 33

**_Trichinella spiralis_** **(_Trichina_ worm)** **_Intestinal nematode_** **(round worms)** lab tests / tx

Answer 33

**_Super Worms!!!_** (**In Nematode City)** * Most often diagnosed by a **Trichinella antibody** test. In some cases a **muscle biopsy** may be performed. * **_High_ eosinophil count** (**_eosinophilia)_**. * **tx** with **Al**_bend_**azole\*** **\***(**Al**_bend_**azole** causes microtubule dysfunction to make worms immobile. **_Dont_** give **microtubule inhibitors** to **pregnant** women. If pregnant **give** **Pyrantel **_pam_**oate**)

Question 34

**_Eosinophil_**

Answer 34

**WBC** w/ **_little pink_ granules** & ****_bi_**lobed nuclei**

Question 35

**_Dracunculus medinesis_** (**_Guinea_ worm**) **_Tissue nematode_** **(round worms)** source / signs and symptoms

Answer 35

**_Screamatodes III: Return of the flesh eaters_** * Transmitted by **_ingesting water_ contaminated** with **_copepods_** (small crustaceans) **containing _larvae_** * **Painful** skin **ulcer** * **Worms** (adult female) **coming out of the skin!**

Question 36

**_Dracunculus medinesis_** (**_Guinea_ worm**) **_Tissue nematode_** **(round worms)** lab tests / tx

Answer 36

**_Screamatodes III: Return of the flesh eaters_** * Diagnosed via **worms** (adult female) **coming out of the skin!** * **Peripheral _eosinophilia_** * Pull out by **_spinning_ matchsticks** or **pencil slowly** over several **days**. * **_Metronidazole_** will help **speed up** the process (but not cure it)

Question 37

**_Onchocerca volvulus_** (**_Filaria_** **worm**) **_Tissue nematode_** **(round worms)** source / signs and symptoms

Answer 37

**_Screamatodes III: Return of the flesh eaters_** * Found around **_rivers_** in Africa, C. america and S. America * **_Black fly_** **_bites_** human host → **larvae burrow** down **into** the hosts **skin** → make **micro filarial** that **come back out**, starting as **scattered puritic papules** → **making _hyper_** **and _hypo_ _pigmented_ spots**. (**Hypo** usually **on shins** of **older** patients) * **_River blindness_!!!** 2nd leading cause of blindness after Trachoma (Chlamydia)

Question 38

**_Onchocerca volvulus_** (**_Filaria_** **worm**) **_Tissue nematode_** **(round worms)** lab tests / tx

Answer 38

**_Screamatodes III: Return of the flesh eaters_** * **_Eosinophilia_** * **Microfilaria** on **skin biopsy** under microscope. * Tx with ****_Iver_**mectin**

Question 39

**_Wucheria bancrofti_** (**_Thread_ worm**) **_Tissue nematode_** **(round worms)** source / signs and symptoms

Answer 39

**_Screamatodes III: Return of the flesh eaters_** * **_Mosquitos_** are **intermediate host** → **bite** human and deposit larvae on **skin** → which **enter** the **lymph** system → **_lymphadenopathy_** * **_Elephantiasis_** (From long standing lower extremity lymphodema) * **Microfilaria** travel to the **lungs** and cause ****_hyper_**sensitivity rxn**

Question 40

**_Wucheria bancrofti_** (**_Thread_ worm**) **_Tissue nematode_** **(round worms)** lab tests / tx

Answer 40

**_Screamatodes III: Return of the flesh eaters_** * Organisms can be seen on **_thick_ blood smear** * **_Eosinophilia_** * Tx with ****_Diet_**hyl**_carb_**amazine**

Question 41

**_Toxicara canis_** (**_Dog_ roundworm**) **_Tissue nematode_** **(round worms)** source / signs and symptoms

Answer 41

**_Screamatodes III: Return of the flesh eaters_** * Transmitted by ingestion of food **contaminated** with **_dog_** or **_cat_** **_feces_** containing the eggs. * **Parasitic larvae** **_never_ mature** out of larvae stage. * AKA **_Visceral_** **_larvae migrans_** * AKA **_Ocular_** **_larvae migrans_** if it gets i**nto the eye** → can cause **_blindness_**

Question 42

**_Toxicara canis_** (**_Dog_ roundworm**) **_Tissue nematode_** **(round worms)** lab tests / tx

Answer 42

**_Screamatodes III: Return of the flesh eaters_** * **Blood tests** to detect **antibodies** to toxocara * **_Eosinophilia_** * Tx with **Al**_bend_**ozole**

Question 43

**_Loa Loa_** (**_Filaria_ worm**) **_Tissue nematode_** **(round worms)** source / signs and symptoms

Answer 43

**_Screamatodes III: Return of the flesh eaters_** * **Bite** from **_deer fly_** → adult Loa Loa worm **migrates** throughout the **subcutaneous tissues** of humans * **Transient angioedema**, localized **subcutaneous swellings** (AKA **_Calabar swellings_**; red and itchy) * AKA **"_African Eye Worm_"** (occasionally crosses into subconjunctival tissues of the **eye** where it can be **easily observed!**)

Question 44

**_Loa Loa_** (**_Filaria_ worm**) **_Tissue nematode_** **(round worms)** lab tests / tx

Answer 44

**_Screamatodes III: Return of the flesh eaters_** * Diagnosed with a **blood smear**. * **_Eosinophilia_** * Tx with ****_diet_**hyl**_carb_**amazine** and **al**_bend_**ozole**

Question 45

_**Tinnea soleum** and **sagginatum**_ **_Cestodes_** **(tape worms)** lab tests / tx

Answer 45

**_Cestode County Carnival_** * **O&P** stool sample will show **_hooks_** on **proglottid** (segment) **heads** of **T. _soleum_** (pig intermediate!), _**no** hooks_ on **T.** **_sagginatum_** (cow intermediate!)**.** * **tx** with ****_P_**a_r_a**_z_**iquanta**_l_**** * ****_Neuro_**cysticercosis tx** with addition of **a**_bend_**ozle**

Question 46

_**Tinnea soleum** and **sagginatum**_ **_Cestodes_** **(tape worms)** Hosts

Answer 46

**_Cestode County Carnival_** Often found in **immigrants** or **farmers**. * **Intermediate** hosts for **T. **_sol_**eum** are **_pigs._** * **intermediate** hosts for **T.** **_sag_******_g_**inatum** are **_cows_.**

Question 47

_**Tinnea soleum** and **sagginatum**_ **_Cestodes_** **(tape worms)** **2 types** of **transmission**

Answer 47

**_Cestode County Carnival_** 1. Ingestion of **_cysts_** or **larvae** in **_undercooked meat_** → **GI issues** or **mal**absorption (**_Taeniasis_**) 2. Ingestion of **_poop water_** contaminated with Tinnea **_eggs**_ → goes to _**brain**_ (_****Neuro**_cysticercosis**) or **_tissues_** (**Cysticercosis**).

Question 48

_**Tinnea soleum** and **sagginatum**_ **_Cestodes_** **(tape worms)** signs and symptoms

Answer 48

**_Cestode County Carnival_** * **_Taeniasis_**: Gi issues or malabsorption * **Cysti****_cercosis_**: Lumps in tissue under skin * ****_Neuro_**cysticercosis**: **Seizures**, lesions (**_swiss cheese_** **appearance!**) in brain, eyes, and skin, hydrocephalus

Question 49

**_Diphyllobothrium latum_** **_Cestodes_** **(tape worms)** source / signs and symptoms

Answer 49

**_Cestode County Carnival_** Found in **uncooked** or **undercooked _fish_**. Causes **diarrhea** (**sm.** intestine) & associated **_B12_** (**Cobalamin**) **deficiency** → ****_Mega_**loblastic _anemia_**

Question 50

**_Diphyllobothrium latum_** **_Cestodes_** **(tape worms)** lab tests / tx

Answer 50

**_Cestode County Carnival_** * **O&P** stool sample will show **proglottid** segments. **\* Largest** tapeworm, up to **10 meters**!!! * **tx** with ****_P_**a_r_a**_z_**iquanta**_l_**** or ****_Nicl_**osamide**

Question 51

**_Echinococcus granulosus_** **_Cestodes_** **(tape worms)** source / signs and symptoms

Answer 51

**_Cestode County Carnival_** **_Dogs_** are the **definitive** host → **_Sheep_** are the **intermediate** host → **_Humans_** are **incidental** hosts. * Transmission to humans via **dog feces** (in food or water) * Cause **_hydated_** **_cysts_** (clear fluid inside the cysts, look like slow growing tumors) * Cyst like mass in **liver** shows "**_Eggshell_ calcifications**" on **CT**

Question 52

**_Echinococcus granulosus_** **_Cestodes_** **(tape worms)** lab tests / tx

Answer 52

**_Cestode County Carnival_** * "**Eggshell** calcifications" on **CT** of **liver** * When **_cysts rupture_** they can cause an **_anaphylaxis_ reaction**! * When attempting **removal**, must **inject with solution** (ethanol or hypertonic saline) **to kill** the **cysts** **_before_** **removal**. * **_Eosinophilia_**

Question 53

**_Schistosoma mansoni, japonicum, haematobium_** **_Trematodes_** **(flukes / flat worms)** source / infection cycle

Answer 53

**_San Fran-schisto ocean park_** (Schistosomiasis) * Free living **aquatic** organisms → gain **entrance through** the **_skin_** → **enter blood** stream → carried to **liver** → **_mature_** into adults **_in the liver!_** → humans **poop and pee** into **water** → **_snails_** become **_intermediate_ hosts** → adult then **migrate _AGAINST**_ the _**portal_ flow** in the **venus** system to reach their destination. * **S. mansoni** and **S. japonicum** like to **reside** **in** **mesenteric** veins. * **S. haematobium** likes to **reside** in veins of **bladder.**

Question 54

**_Schistosoma mansoni, japonicum, haematobium_** **_Trematodes_** **(flukes / flat worms)** signs and symptoms

Answer 54

**_San Fran-schisto ocean park_** (Schistosomiasis) * **_Swimmers itch_** where **larvae** penetrate the skin. _**S. mansoni** and **S. japonicum**_: * **_Portal_ HTN** → (chronically) GI distension and abdominal pain. * **_Liver_ cirrhosis** and **jaundice**. **_S. haematobium_**: * **_Hematuria_** in **bladder** and **risk** of bladder **_cancer_**.

Question 55

**_Schistosoma mansoni, japonicum, haematobium_** **_Trematodes_** **(flukes / flat worms)** lab tests / tx

Answer 55

**_San Fran-schisto ocean park_** (Schistosomiasis) _**Tx** for **all** Trematodes (**flukes**)_: ****_Pr_**a_z_iquanta**_l_**** _On stool **O&P** you will see_: * **_S. mansoni_**: **large lateral spine** on the **side** of the body of the egg * **_S. japonicum_**: **small spine** (or absent) on eggs. Mostly **round**. * **_S. haematobium_**: **Large terminal** **spine**

Question 56

**_Clonirchis sinensis_** **_Trematodes_** **(flukes / flat worms)** source / signs and symptoms

Answer 56

**_San Fran-schisto ocean park_** * **"_Chinese_ _liver_ fluke"** * **_Snails_** are **_intermediate_ host** → transfered to **_fish_** → Humans eat **_cysted_ larvae** in **uncooked _fish_**. _Leads to_: * **_Biliary_ track _fibrosis**_ and _****cholangio**_carcinoma** (bile duct cancer) * **_Pigmented_ gallstones**

Question 57

**_Clonirchis sinensis_** **_Trematodes_** **(flukes / flat worms)** lab tests / tx

Answer 57

**_San Fran-schisto ocean park_** _**Tx** for **all** Trematodes (**flukes**)_: ****_Pr_**a_z_iquanta**_l_**** _On stool **O&P** you will see_: * **_Operculated_ eggs** (looks like **little hats** on eggs)

Question 58

**_Parogonimus westermonti_** **_Trematodes_** **(flukes / flat worms)** source / signs and symptoms

Answer 58

**_San Fran-schisto ocean park_** * **"_Lung_ fluke"** * **_Snails_** are **_intermediate_ host** → transfered to **_crab**_ → Humans eat _**cysted_ larvae** in **undercooked _crab meat_**. _Leads to_: * **_Chronic_ cough** w/ **_bloody_ sputum**

Question 59

**_Parogonimus westermonti_** **_Trematodes_** **(flukes / flat worms)** lab tests / tx

Answer 59

**_San Fran-schisto ocean park_** _**Tx** for **all** Trematodes (**flukes**)_: ****_Pr_**a_z_iquanta**_l_**** _On stool **O&P** you will see_: * **_Operculated_ eggs** (looks like **little hats** on eggs)