Diseases of the Digestive System (Part III) - Exam 5

What are 3 parasitic diseases of the digestive system caused by protozoa?

1. Giardiasis

2. Cryptosporidiosis

3. Amoebic dysentery

What are 4 parasitic diseases of the digestive system caused by helminths?

1. Ascariasis

2. Tapeworms

3. Trichinosis

4. Schistosomiasis

How does Giardiasis appear under the microscope?

flagellated, looks like eyes staring at you

Transmission of Giardiasis

drinking contaminated water

What organism causes Cryptosporidiosis?

Cryptosporidium

Where is Cryptosporidiosis found?

In contaminated water

-swimming pools

-public water supply

What organism causes Amoebic dysentery?

Entamoeba histolytica

How are helminth infections diagnosed?

-eosinophilia (increase in eosinophils)

-history of travel

-discovery of eggs in stool, or larvae, or adult worms in other tissues

Are helminths normally problematic in the body?

problems arise when worms get lost

Treatment for helminth infections?

antihelminthic drugs

How is Ascariasis transmitted?

ingestion of eggs from the soil

If a patient has Ascariasis and worms get lost, where will they exit the body?

anus, nose, mouth

What organism causes Tapeworm?

Taenia

How are tapeworms transmitted?

consumption of undercooked fish, beef, or pork

What happens when tapeworms get lost in the body?

1. cysts in animal muscle

2. cysticercosis - human organs

3. Neurocysticercosis - brain

Culture/Diagnosis of tapeworms

eggs or segments in stool

What organism causes Trichinosis?

Trichinella spiralis

How is Trichinosis transmitted?

eating undercooked pork

What organism causes Schistosomiasis?

Schistosoma

Life cycle of Schistosomiasis

1. Egg hatches in water and swims to a snail

2. Multiplies into a larger larva (cercaria)

3. Cercaria attach themselves to human skin and penetrate hair follicles

4. Pass into small blood and lymphatic vessels

5. Carried to liver where they achieve sexual maturity and mate