CC Sept 2017 Cryptosporidosis

echoecho's version from 2017-10-22 17:32


Question Answer
What is Cryptosporidium?parasitic protozoa found in all regions of the US and throughout the world
Cryptosporidium was first identified as a cause of human infection in _____?1976
During the early 1980s, cryptosporidiosis was a major cause of chronic diarrhea in what patients?AIDS
It is also the cause of community outbreaks of diarrhea in ________ patients, including a massive outbreak in Milwaukee in 1993 that affected more than 400,000 people?immunocompetent
Cryptosporidiosis largely remains underrecognized and only ____% of cases in the US are properly diagnosed and reported?1%
Travelers to countries with poorer ________ systems are at increased risk for infection?sanitation
About ____ to ____% of the population of resource-poor countries are host to the parasites, as compared to ____% in higher income countries?5-10%; 1%
What are the two most common species of Cryptosporidium associated with human infection?1) C parvum 2) C. hominis
How is a person infected with Cryptosporidium?1) sporulated oocysts are excreted through the feces of an infected host and infect water sources (drinking water, recreational water sources like water parks) 2) millions of parasites can be excreted in a single bowel movement from an infected human or animal 3) following ingestion of the oocysts, the spores open and the sporozoites infect epithelial cells of the GI tract 3) multiplication and reproduction occur, leading to the shedding of oocysts by the host
Symptoms occur following an incubation period of ____ to ____ days?two; ten
List the common symptoms?1) watery diarrhea 2) crampy abdominal pain 3) fever 4) nausea 5) vomiting 6) dehydration 7) weight loss
In healthy, immunocompetent hosts, symptoms may last for ___ to ___ weeks and occasionally as long as ____ weeks?1) one to two 2) four
In immunocompromised hosts, including patients with AIDS, cancer, those undergoing chemotherapy or those who have received an organ transplant, the infection may be severe and even _____?fatal
Cryptosporidium infection in children, particularly those who were born ______, may also be more severe?prematurely
Diagnosis can be challenging, why?because the symptoms mimic many other infectious diarrheal illness
How is diagnosis made?1) identification of oocysts in stool 2) the usual test for ova and parasites does not identify the organisms, and a special exam must be required
How are stool examples examined?1) using acid-fast staining 2) direct fluorescent antibodies 3) enzyme immune assays
What test is used in reference labs but is not widely available?polymerase-chain-reaction testing
*** Due to their ______ ______, the oocysts resist even proper chlorination of pool water, so prevention is key to avoiding cryptosporidosis?thick walls
The CDC recommends what?1) proper hand hygiene 2) avoiding exposure to potentially contaminated sources of water (including lakes, rivers, streams, unfiltered / unboiled water) 3) showering prior to using recreational water sources 4) not swallowing water when swimming
For immunocompetent patients, treatment is largely _____?supportive
What is the treatment of cryptosporidosis in immunocompetent patients?Nitazoxanide (Alinia) 500 g BId x 3 days
What is the role of Nitazoxanide (Alinia) in immunocompromised patients?role is not clear
Improving what may improve symptoms related to the Cryptosporidium (e.g. antiretroviral therapy in patienst with AIDS) but not clear the infection?immune status
*** SUMMARY = Cryptosporidiosis is one of the more common types of waterborne illness, though it is _________?underrecognized
*** SUMMARY = In addition to watery diarrhea, it may present with what symptoms?abdominal pain, fever, vomiting and weight loss
*** SUMMARY = Oocysts contineu to be shed up to ___ weeks after resoluation of symptoms; patients must be cautioned not to swim during this time?2