DTM&H - Helminth Spotter UPDATED
ACTUAL Exam Questions and CORRECT
Answers
x10 - CORRECT ANSWER - What magnification do you need to scan on to look for
helminth eggs?
Ascaris lumbricoides (giant worm) - CORRECT ANSWER - What species has both
infective and non-infective eggs down a microscope?
Fertile = approx 60um; condensed nuclear material with double notched membrane
Infertile = 75-90um; wooly nuclear material that fills cells; single thick notched membrane -
CORRECT ANSWER - How do you tell the difference between fertile and infertile ascaris
eggs?
- Looks like a tea tray
- Bipolar plugs at either end (like handle)
- Barrel shaped
- 50-60um - CORRECT ANSWER - What are the features of the trichuris trichuria egg?
- Looks like a bunch of grapes inside
- Very thin walled
- Glassy apperance
- 40-60um in size - CORRECT ANSWER - What are the features of the hookworm egg?
Vental teeth - CORRECT ANSWER - What are the features that allow identification of the
adult hookworm?
- Strongyloides (most commonly)
,- Hookworm (if after 24h as eggs hatch within 24-48h into larvae) - CORRECT
ANSWER - Which cestode worm larvae might you see in faeces? (2)
L1 stages of strongyioides
Can get L1 stages of hookworm too - CORRECT ANSWER - What stage of larvae are
commonly seen in faeces?
Likely means you have hyper infection - CORRECT ANSWER - What does it mean if you
see L3 stage strongyloides faeces in larva?
If L1 should fit nicely into x40 field
If L3 won't fit into x40 field - CORRECT ANSWER - What size magnification is
appropriate to see an L1 larvae in the stool?
Hookworm = long buccal cavity; club shaped oesophagus
Strongyloides = no real buccal cavity; double bulbed oesophagus - CORRECT
ANSWER - How do you differentiate an L1 hookworm from an L1 strongyloides larva?
(2)
Strongyloides - oesophagus is half body length; tip of tail looks like its been cut off, NO
SHEATH
Hookworm - outside sheath, tip of tail pointed, oesophagus is < half length of body - CORRECT
ANSWER - How do you differentiate an L3 hookworm from an L3 strongyloides larva?
(2)
- Necator americanus = 2 cutting blades
- Ancylostoma duodenale = cutting teeth - CORRECT ANSWER - How do you tell the
difference between the two adult species of hookworm?
Small intestine (look for undulating villi) - CORRECT ANSWER - If you are looking at
strongyloides, which part of the intestine do you expect to see it in?
, - Would see eggs (look like thin walled cloud of cells) in mucosa
- Larve (look like fragments of pink tubes with blue dots in) (can be in tissue or lumen)
- Adult worms all within mucosa
- Lots of orange eosinophils
- Inflammatory cell infiltration in the lamina propria - CORRECT ANSWER - What
features of strongyloides in the small intestine would you see? (4)
- 55microns in size
- Typically flat on one side - CORRECT ANSWER - What are the features of enterobius
vermicularis eggs?
False - usually get larvae not eggs - CORRECT ANSWER - T or F it is common to see
enterobius vermicualris eggs in faeces?
Lateral aleo
Double bulb oesophagus - CORRECT ANSWER - What are the features of the adult
enterobius vermicularis?
Striated muscle - CORRECT ANSWER - Which tissue will you likely see trichinella in?
- See encysted larvae in striated muscle
- Look for pink round bodies that contain larvae (pink tube with blue dots in)
- Becomes walled off with pink collagen capsule - CORRECT ANSWER - What are the
features of trichinella that allow you to identify it on a tissue slide?
- CORRECT ANSWER -
ACTUAL Exam Questions and CORRECT
Answers
x10 - CORRECT ANSWER - What magnification do you need to scan on to look for
helminth eggs?
Ascaris lumbricoides (giant worm) - CORRECT ANSWER - What species has both
infective and non-infective eggs down a microscope?
Fertile = approx 60um; condensed nuclear material with double notched membrane
Infertile = 75-90um; wooly nuclear material that fills cells; single thick notched membrane -
CORRECT ANSWER - How do you tell the difference between fertile and infertile ascaris
eggs?
- Looks like a tea tray
- Bipolar plugs at either end (like handle)
- Barrel shaped
- 50-60um - CORRECT ANSWER - What are the features of the trichuris trichuria egg?
- Looks like a bunch of grapes inside
- Very thin walled
- Glassy apperance
- 40-60um in size - CORRECT ANSWER - What are the features of the hookworm egg?
Vental teeth - CORRECT ANSWER - What are the features that allow identification of the
adult hookworm?
- Strongyloides (most commonly)
,- Hookworm (if after 24h as eggs hatch within 24-48h into larvae) - CORRECT
ANSWER - Which cestode worm larvae might you see in faeces? (2)
L1 stages of strongyioides
Can get L1 stages of hookworm too - CORRECT ANSWER - What stage of larvae are
commonly seen in faeces?
Likely means you have hyper infection - CORRECT ANSWER - What does it mean if you
see L3 stage strongyloides faeces in larva?
If L1 should fit nicely into x40 field
If L3 won't fit into x40 field - CORRECT ANSWER - What size magnification is
appropriate to see an L1 larvae in the stool?
Hookworm = long buccal cavity; club shaped oesophagus
Strongyloides = no real buccal cavity; double bulbed oesophagus - CORRECT
ANSWER - How do you differentiate an L1 hookworm from an L1 strongyloides larva?
(2)
Strongyloides - oesophagus is half body length; tip of tail looks like its been cut off, NO
SHEATH
Hookworm - outside sheath, tip of tail pointed, oesophagus is < half length of body - CORRECT
ANSWER - How do you differentiate an L3 hookworm from an L3 strongyloides larva?
(2)
- Necator americanus = 2 cutting blades
- Ancylostoma duodenale = cutting teeth - CORRECT ANSWER - How do you tell the
difference between the two adult species of hookworm?
Small intestine (look for undulating villi) - CORRECT ANSWER - If you are looking at
strongyloides, which part of the intestine do you expect to see it in?
, - Would see eggs (look like thin walled cloud of cells) in mucosa
- Larve (look like fragments of pink tubes with blue dots in) (can be in tissue or lumen)
- Adult worms all within mucosa
- Lots of orange eosinophils
- Inflammatory cell infiltration in the lamina propria - CORRECT ANSWER - What
features of strongyloides in the small intestine would you see? (4)
- 55microns in size
- Typically flat on one side - CORRECT ANSWER - What are the features of enterobius
vermicularis eggs?
False - usually get larvae not eggs - CORRECT ANSWER - T or F it is common to see
enterobius vermicualris eggs in faeces?
Lateral aleo
Double bulb oesophagus - CORRECT ANSWER - What are the features of the adult
enterobius vermicularis?
Striated muscle - CORRECT ANSWER - Which tissue will you likely see trichinella in?
- See encysted larvae in striated muscle
- Look for pink round bodies that contain larvae (pink tube with blue dots in)
- Becomes walled off with pink collagen capsule - CORRECT ANSWER - What are the
features of trichinella that allow you to identify it on a tissue slide?
- CORRECT ANSWER -
