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IPLab:Lab 11:Ascariasis

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File:IPLab11Ascariasis7.jpg|This high-power photomicrograph of the fecal specimen from this patient shows a Giardia lamblia cyst (arrow).
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== Study Questions ==
* <spoiler text="Was the original diagnosis of streptococcal pharyngitis in error? Does it relate to the subsequent intestinal obstruction?">The patient did have streptococcal pharyngitis. The high fever produced by the streptococcal infection "upset" the intestinal parasites and made them become more active and possibly contributed to the mass of worms that resulted in the intestinal obstruction.</spoiler>
* <spoiler text="How is ascariasis transmitted? How does this relate to the multiplicity of parasites identified in this patient's stool specimen?">Ascariasis and the two protozoan parasites seen in this woman are common in countries with poor sanitation. This can include fecal contamination of water, soil and therefore fruits and vegetables that are not washed adequately. After Ascaris eggs are excreted in the feces of the primary host, the eggs must incubate in soil for two weeks before they are infective. After two weeks, ingested embryonated eggs hatch and the larval worms burrow through the wall of the small intestine and enter the blood. They are primarily filtered out in the capillaries of the lung where they burrow into the alveoli, are coughed up and swallowed. They then take up residence in the small intestine. Children who practice geophagia commonly have very high Ascaris loads in areas with promiscuous defecation. The two protozoa form cysts in the colon of patients who do not have severe diarrhea and are infectious as soon as passed. The cysts remain viable in soil and water for weeks to months. The most likely common source for these three organisms would be non-chlorinated water or fruits and vegetables contaminated with soil or water. A food handler with Ascaris is not a public health threat while infection with either of the other organisms is a risk for transmission.</spoiler>
{{IPLab 11}}
[[Category: IPLab:Lab 11]]
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