Parasitic infections of GI tract - Schoeny Exam 3 Flashcards
What is the most common cause of epidemic water borne diarrheal disease in the US?
Giardia lamblia
Two forms of giardia?
Troph and cysts forms
Giardia colonizes what areas of the GI tract?
Duodenum and jejunum
Other than drinking contaminated water, how can giardia be spread?
Fecal to oral transmission.
Symptoms of giardia?
Sudden onset of explosive diarrhea 1-3 weeks after exposure. Abdominal cramping flatulence low grade fever nausea/vomiting
Gold standard diagnosis for giardia?
Stool O and P
Other tests for giardia?
ELISA stool antigen testing
Stool PCR
Duodenal biopsy
Treatment for giardia?
Metronidazole or tinidazole
You get a microbiology report stating “falling leaf motility”. What bug should you think of?
Giardia
A patient undergoes surgery for a liver abscess. The procedure note mentions “chocolate milk-like” drainage from the abscess. What bug should you think of?
Entamoeba histolytica
Entamoeba histolytica starts by invading the intestinal epithelium. What extraintestinal sites can it spread to?
Liver primarily, but also the lungs, pericardium, and brain
Diagnosis of Entamoeba histolytica is done by ____.
O and P, serology
Lab report comes back showing growth of Entamoeba coli. Are you concerned?
No, it is non-pathogenic
Treatment for Entamoeba histolytica?
Metronidazole or tinadazole
What parasite does not cause symptoms in immune competent patients but is a problem in immunosuppressed/HIV patients?
Cryptosporidium
What symptoms does cryptosporidium cause in immunosuppressed patients?
Diarrhea, dehydration, lung or gallbladder involvement.
Diagnosis of cryptosporidium done by _____.
stool AFB stain
What is the only approved treatment for cryptosporidium?
Nitazoxinide (alinia)
Helminth infections are caused by ______.
Worms
Give the common name for the following Helminth infections: Ascaris lumbricoides Trichinella spirosis Enterobius vermicularis Ancylostoma and Necatur
Ascaris lumbricoides - intestinal roundworm
Trichinella spirosis - trichinosis
Enterobius vermicularis - pinworm
Ancylostoma and Necatur - hookworms
What is the largest and most common Helminth infection in humans?
Ascaris lumbricoides
What lab finding is a hallmark of Helminth infections?
True eosinophilia
Describe the life cycle of Ascaris lumbricoides.
Adult worms live in small intestine and deposit eggs into intestinal lumen.
Eggs passed into feces.
Larvae from ingested eggs enter bloodstream. Get stuck in pulmonary capillaries and rupture into alveolar spaces.
Larvae coughed up and reingested.
Symptoms of Ascaris lumbricoides?
Depend on worm load.
High worm load - cough, fever, wheezing, SOB, oxygen desaturation
Diagnosis of Ascaris lumbricoides?
Stool O and P
Eosins and larvae in sputum.
Treatment of Ascaris lumbricoides?
Mebendazole or albendazole
A corticated egg should make you think of what parasite?
Ascaris lumbricoides
Trichinella spirosis is commonly found where?
Undercooked meat, especially pork, wild game, and bear.
Trichinella spirosis infects what tissue?
Muscle tissue
Symptoms of trichinosis?
Paralysis, weakness, and pain of muscles.
Lab findings in trichinosis?
Elevated CK, LDH and eosinophils
Treatment for trichinosis?
Albendazole or mebendazole
Enterobius vermicularis causes what symptoms?
Anal pruritis
Diagnosis of Enterobius vermicularis?
Scotch tape prep - Positive for adult worm in anal area
Treatment for Enterobius vermicularis?
Mebendazole
Enterobius vermicularis is highly contagious. What should be recommended when you diagnose one patient?
Recommend treatment of all in family
Wash all bedding with hot water and detergent
Necatur and Ancyclostoma are hookworms. What systems can be affected by them?
Pulmonary, dermal, and GI systems.
T/F? Hookworms can enter through the skin.
True
Cutaneous larva migrans is caused by what type of hookworm?
Dog hookworm
T/F? Treatment for cutaneous larva migrans is surgical excision.
False - this will spread eggs and infection will be worse
Treatment for hookworms?
Mebendazole or albendazole
