Enteric Parasites Flashcards
What parasite testing do we do in MMUH?
Ovum Parasites
What is the minimum testing criteria for parasites
○ Recent foreign travel
○ 2 weeks + diarrhea
○ Macroscopically can see worms in stool
○ Transplant patients
○ Immunocompromised
If from the infectious disease ward
What is often the case with rejected GP samples?
Usually lack enough clinical details to be processed
GP usually rings after sample is rejected and provides more clinical details
Regs usually accept and process sample
Where are positives most often from
Middle East
How common is parasite testing
A specialism to the Mater
Not tested for in many hospitals -> majority refer out
How are parasites detected
Light microscopy
What are the most common parasites
Protozoa
Cryptosporidium
Giardia
What samples are required for parasites
- Ideally three stool samples should be sent over a 10 day period
According to reproductive cycle of parasites – more likely to see eggs at certain times of the day etc
How are samples processed for parasites
○ Add a ‘pea-sized’ amount to a sample container of formalin
○ Try and mush up the sample as much as possible
○ If you can macroscopically see any worms then you don’t need to spin the sample
○ If no worms the sample is centrifuged to form a pellet
Any formalin supernatant is decanted off
○ Pellet can be kept in formalin – worms will be preserved/fixed
○ Urine samples don’t need to be kept in formalin and don’t need to be spun
What should be done if you can macroscopically see worms in a sample?
Don’t spin the sample
How do we preserve any worms (if present)?
Formalin
How are urine samples processed differently for parasites
Don’t need to be kept in formalin
Don’t need to be spun
Talk about the Tubes used for processing parasites
○ MidiParasep Tubes
○ Composed of a filter and a formalin container
○ Filter keeps back any deposit when sample is pun
○ Parasites can be kept in formalin indefinitely
Can add saline if needed
