Infections of GI tract Parasitic Infections: schoenwald (exam 3) Flashcards
List Ex’s of Parasitic Infections:
- Giardia
- Amoeba
- Helminths
- Cryptosporidia
Giardia Lamblia is the MC cause of epidemic _____ borne diarrheal disease in US
water borne
Giardia lamblia:
- Troph and ____ forms
- Most frequently identified _______ in the US
- Troph and cyst forms (can infect in these forms)
- Most frequently identified **protozoan in US, especially Rocky Mountain region
Giardia lamblia:
- colonizes the ______ and jejunum
- disrupts the ______ function
- fecal to _____ transmission
- Colonizes *duodenum and jejunum
- Disrupts the epithelial fxn=malabsorption
-Fecal to oral transmission
Giardia lamblia:
Sx?
- Sudden onset explosive diarrhea 1-3 weeks after exposure
- Abdominal cramping
- Flatulence
- Low grade fever
- Nausea/vomiting
Giardia: Dx
-gold standard test?
- O and P= gold standard (ova and parasite (O&P) exam)
- ELISA-Stool Antigen testing (this one is used more now, BUT know the gold standard for boards)
- Stool PCR
- Duodenal biopsy
Giardia:
tx?
metronidazole or tinidazole
Giardia: prevention?
DONT drink the water!! lol
can cause significant weight loss
Entamoeba histolytica:
trophs invade the intestinal _______
Trophs invade intestinal epithelium, can penetrate venules and lymphatics to gain access to liver
Entamoeba histolytica:
-primary site?
Liver= primary site of extraintestinal disease but may disseminate into lung, pericardium, and brain
Entamoeba histolytica:
clinical sx?
-prodrome Sx?
Characteristic fluid description?*
- Prodrome of Sx: diarrhea, abdominal cramping, nausea, vomiting, tenesmus
- Malaise, loss of appetite, weight loss, mental apathy
- Watery stool containing mucus and blood
- Tender liver enlargement-liver abscess
- Meningeal signs-brain abscess
“chocolate milk like” in appearance –> THINK Entamoeba abscess of the liver!! **KNOW
Entamoeba histolytica:
Dx?
Tx?
- O and P (ova and parasite)
- Serology
Tx: metronidazole or tinidazole
-Prevent with good sewage and water treatment plants
(abscesses will need to be drained)**
-cousin to Entamoeba histolytica known as entamoeba coli–> IT IS NOT pathogenic!! -schoenwald
Cryptosporidium:
-etiology?
Contaminated fruit, vegetables and water
Cryptosporidium:
-important in which Pt population?
- Important in immunosuppressed/HIV
- In immune competent individuals, asymptomatic
Cryptosporidium:
-sx?
Diarrhea, dehydration, lung or gallbladder involvement in immunosuppressed
Cryptosporidium:
- dx?
- tx?
-Diagnosis- stool AFB stain, stool Antigen test, stool pcr
Acid fast bacillus stain for cryptosporidium= pinkish reddish
tx: nitazoxinide (Alinia)= ONLY FDA approved tx
Cryptosporidiosis:
US outbreaks 2009-2017
- pools: 37%
- cattle: 15%
- Childcare: 13%
Helminth infections:
-organism? (hint: 4 kinds of worms)
(helminths= are worms)
-Ascaris lumbricoides-intestinal roundworm
- Trichinella spirosis-trichinosis
- Enterobius vermicularis-pinworm
- Ancyclostoma and Necatur-hookworms
Ascaris lumbricoides is the largest and most _____
common
Ascaris lumbricoides:
-describe the worm and route of infection
- Adult worm inhabits small intestine and deposits eggs into intestinal lumen
- Eggs passed into feces
- Larvae from ingested eggs enter bloodstream, pass through alveoli, blocked at pulmonary capillaries, rupture into alveolar spaces
- Coughed and reingested
Ascaris lumbricoides:
-Sx depend on ____
- worm load
- High worm load= cough, fever, wheezing , shortness of breath, oxygen desat
- -Eosinophilia
Ascaris lumbricoides:
Dx?
Tx?
- O and P
- Eosins and larvae in sputum
tx: mebendazole or albendazole
Trichinella spirosis:
- organism?
- etiology?
- Trichinosis
- Raw or undercooked meat esp pork
Trichinella spirosis:
-infection causes?
- Muscle infection with parasite
- ->Paralysis of muscles
- ->Weakness, muscle pain
Trichinella spirosis:
- lab findings?
- tx?
- Elevated CK, LDH, Eosinophils
- Tx: albendazole or mebendazole
Enterobius vermicularis:
- parasite?
- Demographic and MC Sx?
- pinworm
- Sx usually in kids and worse at bedtime
- Anal pruritis
Enterobius vermicularis:
- Dx based on ____
- tx?
**finding adult worm in anal area, scotch tape prep
-Tx: mebendazole, all in family should be treated
Necatur and Ancyclostoma:
-parasite?
Hookworms
Necatur and Ancyclostoma:
- can infect ____ systems
- Sx?
-pulmonary, dermal and GI systems
Sx: specific for area of infection
- Able to enter through skin
- **“hook” onto colon wall, can cause anemia
Hookworm lifecycle
humans are usually the carrier, and human fecal material that gets deposited in soil–> larvae hatch and people that come into contact with that soil or dogs can get the hookworm infection
Cutaneous larva migrans=
=dermal hookworm infections
(typically of the feet)
- Pt may have walked barefoot on the beach and the larvae of the worm hooked onto their foot
- Tx: DO NOT REMOVE THE WORM–> this spreads it more as the eggs hatch
Necatur and Ancyclostoma (“hookworm”):
tx?
Tx: DO NOT REMOVE THE WORM–> this spreads it more as the eggs hatch
**Mebendazole or albendazole
