Diagnosis Of Parasitic Infections

Question 1

Human parasites are organisms that live on or in a person and derive nutrients from that person (its host).

3 types of parasites:

______
_________
_________

Answer 1

protozoa

helminths (worms)

ectoparasites

Question 2

stool specimen

Should be ______

______ substances should be avoided when stool specimens are collected

Collect before ___,_______,______,______ , and ______ agents.

Collection delayed by ________ if these agent have already been administered

Answer 2

fresh

Interfering

barium, mineral oil, bismuth, antibiotics, antimalarial

5 to 10 days

Question 3

COLLECTION METHOD of stool specimen

Clean containers or fixative vials.
Avoided contamination with ____ or____
Labeled with patient name, time and date of collection
If on admission, patient is given bedpan with instructions on how to avoid contamination with urine , a _______ of the specimen, especially that which contains ___,——, or _____ is transferred into a clean, dry, leakproof container.
When the specimen contains worms or tapeworm segments, they are ___________

Answer 3

urine or water

portion (about a spoonful)

mucus, pus, or blood

put in separate containers .

Question 4

NUMBER OF SPECIMENS for a stool sample

Normal examination for stool parasites before therapy includes ____ specimens.

Post therapy specimens not collected unless ___________________

Answer 4

3

patient becomes symptomatic again.

Question 5

COLLECTION TIMES of stool samples

Three specimens collected on separate days.

Within no more than ___ days.

Exception: patient with _______, organisms might be missed because of ____________ related to ____ loss.

Answer 5

10

severe, watery diarrhea

tremendous dilution factor

fluid

Question 6

SPECIMEN TYPE, STABILITY, AND PRESERVATION in stool sample

Fresh specimens mandatory for recovery of _________

Liquid stool should be ______ within _____ of passage (______)

Soft stool examined or preserved within ______ of passage ( ______ ) dientamoeba fragilis trophozoites

Formed stool should be examined or preserved within ______ of passage.

Answer 6

motile trophozoites.

examined or preserved; 30 minutes ; trophozoites

1 hour ; trophozoitess & cysts

24 hour

Question 7

List 4 stool fixatives

Answer 7

Formalin, sodium acetate- acetic acid-formalin (SAF), schaudinn’s fluid, and polyvinyl alcohol (PVA)

Question 8

PRESERVATION OF STOOL
SPECIMENS
Delay in receiving stool specimens, place in ______

Keep in mind, a _______ is mandatory.

May want to perform screening methods:______ or ________.

Make sure the fixative is compatible with the kit you are using.

Disposal regulations for compounds containing _____ are becoming more STRICT

Answer 8

fixatives

permanent stained smear

fluorescent-antibody (FA) or enzyme immunoassay (EIA)

mercury

Question 9

COLLECTION OF BLOOD

Parasites: _____,________,______,______ and microfilariae.

Collect fresh blood (____ anticoagulant)

Smears prepared within _____ after the specimen is drawn.

Answer 9

Plasmodium, Babesia, Trypanosoma, Leishmania,

EDTA; 1 hour

Question 10

In a blood sample, One negative specimen rules out the possibility of a parasitic infection.

T/F

Answer 10

F

One negative specimen does not rule out the possibility of a parasitic infection.

Question 11

Microscopic examination faeces

Direct wet mount:

Thin ______ of small amount of faeces

Few drops of ________

________ mount

Look for (x10 or X40)

Protozoa (_______), cyst, eggs and larva of helminths, crystals (____________)

Answer 11

emulsion

saline

Lugol’s iodine

trophozoite

charcot leyden

Question 12

Molecular diagnosis
(using stool sample)

If an unequivocal identification of the parasite can not be made, the stool specimen can be analyzed using molecular techniques such as ______________.

Answer 12

polymerase chain reaction (PCR)

Question 13

Molecular diagnosis
(using stool sample)

PCR amplified fragments can be analyzed by using _________ (RFLP) or _______ if further characterization is needed.

Answer 13

restriction fragment length polymorphisms

DNA sequencing

Question 14

Blood examination

Fresh capillary blood of _____ or ____

(Arterial or Venous?) blood collected in ______ (anticoagulant)

Answer 14

finger or ear lobe

Venous
EDTA

Question 15

Blood examination

Blood sample will be used for :

Microscopic examination( ________, ___-, _______ for microfilaria).
Molecular diagnosis
Detection of parasite antigen
Isolation of organisms
Special tests

Answer 15

Thin Smear; Thick smear

Wet mount

Question 16

Microscopy of blood

Examination of thick and thin peripheral blood smears stained with _____ or other appropriate stains is used for detection and identification of species of Plasmodium, Babesia, Trypanosoma, Brugia, Mansonella , and Wuchereria

The sensitivity of these methods may be enhanced by concentration procedures (eg, _____ test, ________, and _______).
•

Answer 16

Giemsa

buffy coat

filtration

Question 17

Thick blood film

Screen (small or large?) amount of blood (____ infection)
Can be stained ____

Answer 17

Large

light

latter

Question 18

Thin blood film

In ______, Parasitized red blood cells and parasites

___________ identification

Answer 18

Malaria

Definite species

Question 19

Microfilaria

Sample collection according to ______ of microfilaria
Concentration by _______ or ______ (examine the filter)

Answer 19

periodicity

sedimentation

membrane filtration

Question 20

Sputum examination
Microscopic examination of sputum can identify:

_________ eggs
_______ larva
________ larvae
 hookworm larvae, and rarely _______

Answer 20

Paragonimus westermani

Strongyloides stercoralis

Ascaris lumbricoides

Entamoeba histolytica.

Question 21

Sputum should be obtained from the __________ not _____

Answer 21

lower respiratory passages

saliva

Question 22

Sputum specimens should be collected ___________

Answer 22

first thing in the morning.

Question 23

Vaginal swabs

Demonstration of _________ trophozoites is usually done by preparing _________ made from vaginal swabs or scrapings.

Answer 23

Trichomonas vaginalis

wet mounts

Question 24

Tissue Specimens for Free-living Amebae (FLAs)

Tissue specimens, including _____, ___________ specimens, may be collected for the detection of free-living amebae (Naegleria, Balamuthia, and Acanthamoeba).

used for
•Tissue slides stained with ________
•Unstained slides (for _________).
•Unfixed _____ tissue or CSF for PCR.
•Unfixed _______ (for Acanthamoeba).
•______-embedded tissue block.

Answer 24

biopsy

surgical or necropsy

hematoxylin and eosin (H&E).

indirect Immunofluorescence, or IIF

corneal scrapings

Paraffin

Question 25

The most reliable and widely used technique for demonstrating pinworm eggs (__________) is the _______ or ______ procedure.

Answer 25

Enterobius vermicularis

cellulose tape or swube tube

Question 26

Cellulose Tape or Swube Tube Procedure for Demonstration of Pinworm Eggs

The _____ part of the swube tube or tape is applied to the ______ first thing in the morning.

Specimens should be collected on _______ (prior to or after?) bathing.

• If an infection is present, ____ and sometimes _____ of Enterobius vermicularis will be present
on the tape and can be seen under the microscope

Answer 26

adhesive

perianal area

three consecutive mornings; prior

eggs; adult worms

Question 27

Urinary schistosomiasis

• Presence of S. _______ eggs in urine is diagnostic for Eggs usually shed in the urine around _____, so an optimum urine specimen for diagnosis should be collected at ____.

The specimen should be immediately centrifuged at ____ × g and the sediment examined by _____

Answer 27

haematobium
midday; noon

400; wet mount.

Question 28

Trichomonas vaginalis

______ trophozoites may also be found in the urine, especially in infected ____ patients.

Urine specimen should be centrifuged at ____ × g, the sediment mixed with a drop or two of _____, and examined by ____

Answer 28

Motile

male

400; saline; wet mount

Question 29

Temporary stains, such as _______ is helpful to see T. Vaginalis

Answer 29

methylene blue