FECT

Question 1

ADVANTAGES of CONCENTRATION TECHNIQUE

Answer 1

Maximizes the number of organisms detected which may be too scanty to be seen by direct microscopy alone.

Separate parasites from fecal debris

Question 2

DISADVANTAGES of CONCENTRATION TECHNIQUE

Answer 2

Destroys trophozoite stages

Distorts any cellular components

Question 3

ADVANTAGES of SEDIMENTATION TECHNIQUE

Answer 3

Recovers most ova, cysts, and larvae.

Morphology of most parasites is retained.

Less risk of infection from bacteria and viruses.

Question 4

DISADVANTAGES of SEDIMENTATION TECHNIQUE

Answer 4

Preparation contains debris.

Some parasites do not concentrate well.

Ether is flammable and formalin is an irritant.

Liquid feces do not concentrate well.

Question 5

ADVANTAGES of FLOATATION TECHNIQUE

Answer 5

The concentrate is clear of debris

Question 6

DISADVANTAGES of FLOATATION TECHNIQUE

Answer 6

Delay in examination can result in distortion

Larvae and some fluke eggs do not concentrate

Frequent checking of specific gravity

Question 7

2 Sedimentation techniques

Answer 7

Acid Ether Concentration Technique + 40% HCI

Formalin Ether/Ethyl Acetate Concentration Technique

Question 8

4 Concentration techniques

Answer 8

Brine Floatation (NSs)

Zinc Sulfate Floatation

Sheather’s Sugar Floatation

McMaster Technique

Question 9

A procedure that allow for the detection of parasitic elements (eggs, larvae, oocysts and cysts) that may be missed when examining only a direct wet preparation

Answer 9

FECT

Question 10

FECT

A procedure that allow for the detection of parasitic elements (ELOC) that may be missed when examining only a direct wet preparation

Answer 10

eggs
larvae
oocysts
cysts

Question 11

This technique is not recommended for eggs of_______ and larvae of______

Answer 11

Fasciola spp.

Strongyloides stercoralis

Question 12

FECT

Examples of parasitic stages that might be seen under the microscope

Answer 12

Faciola egg
Entamoeba cysts.
Ancylostoma Egg.

Bacterial rods
Isospora oocyst
Isospora canis (coccidia) oocysts
Coccidia

Question 13

_________ in General

Are techniques used to separate parasites from fecal debris and increase the chances of detecting parasitic organisms when these are in small numbers.

Answer 13

Concentration Techniques

Question 14

2 types of conc. techniques

Answer 14

Sedimentation technique
Floatation/Flotation technique

Question 15

Floatation techniques (3)

Answer 15

Saturated saline
Zinc sulfate
Sheather’s sugar

Question 16

Sedimentation techniques

Answer 16

Saline
Formol ether

Question 17

Use solutions of lower specific gravity than the parasitic organisms, thus concentrating the latter in the sediment.

Answer 17

Sedimentation technique

Question 18

are recommended for general diagnostic laboratories because they are easier to perform and less prone to technical errors.

Answer 18

Sedimentation techniques

Question 19

_____ is the sedimentation technique used at CDC of USA and is recommended by the WHO

Answer 19

FECT

Question 20

Floatation Techniques

Most frequently used:

Answer 20

zinc sulfate

Sheather’s sugar

Question 21

Floatation techniques

Use solutions which have _________ sg than the organisms to be floated so that the organisms rise to the top and the debris sinks to the bottom together with the solution, since mas mabigat sila essentially.

Answer 21

higher specific gravity

Question 22

The main advantage of this technique is to produce a cleaner material than the sedimentation technique.

Answer 22

Floatation technique

Question 23

The disadvantages of most floatation techniques are that the walls of____ and ____ will often collapse, thus hindering identification.

Also, some parasite eggs do not float

Answer 23

eggs and cysts

Question 24

is a widely used sedimentation technique for the diagnosis of intestinal protozoa in preserved stool samples

Answer 24

The formalin-ether concentration technique (FECT)

Question 25

The most commonly used fixatives for stool preservation are either ______ or _______

Answer 25

formalin sodium acetate-acetic acid-formalin (SAF)

Question 26

The use of________ instead of_____ avoids the flammability problem of ____, and EA can be used with specimens preserved in formalin, MIF or SAF.

Answer 26

ethyl acetate ether

Question 27

can be used with specimens preserved in formalin, MIF or SAF.

Answer 27

Ethyl acetate

Question 28

FECT lacks sensitivity for the diagnosis of________

Answer 28

helminths

Question 29

Its diagnostic accuracy is inferior to that of the widely used Kato-Katz technique for the diagnosis of:

Answer 29

Schistosoma mansoni Common soil-transmitted helminths (A. lumbricoides, T. trichiura, and hookworm)

Question 30

______ conical centrifuge tube

Answer 30

15 mL

Question 31

4 layers after final centrifugation

Answer 31

Top layer of ethyl acetate/ether/ A plug of fatty debris that is adherent to the wall of the tube A layer of formalin The sediment ( which should contain the parasite in search of)

Question 32

What can we detect using Sedimentation

Answer 32

•Heavy eggs (Ascaris egg) • Operculated eggs (Trematodes) • Larvae (Strong stercolaris.) • Cysts

Question 33

What can we detect using Floatation

Answer 33

• Non Operculated eggs Trematodes (Schistosoma.) Cestode Nematode (Hookworms) • Cysts

Question 34

Less distortion of cysts occurs with this technique than with ***zinc sulfate method*** and it is more effective in concentrating formalinized specimens.

Answer 34

FECT

Question 35

______ eggs may be missed, however, and concentration of_____ cysts and____ cysts may not be very good.

Answer 35

Hymenolepis nana Giardia lamblia iodamoeba butschlii

Question 36

Ether, ethyl acetate or, if these solvents are unavailable,________.

Answer 36

gasoline

Question 37

is highly volatile and will ignite and explode quickly if there is an open flame or spark nearby.

Answer 37

Ether

Question 38

FECT This procedure makes use of 10% formalin which is an_______, and ether, which can______ in the stool.

Answer 38

all purpose fixative dissolve neutral fats

Question 39

FECT This is useful in the recovery of both

Answer 39

helminth eggs protozoan cysts

Question 40

FECT can also be done with______ stools More parasites can be recovered from formalin preserved samples. Parasite morphology is also better preserved in formalin than in PVA. Sediments from FECT can be stored for a long period of time.

Answer 40

formalin-preserved and PVA-preserved stools.

Question 41

Those who have tried ***ethyl acetate*** claim that it is more efficient than ether in the recovery of______ and _____ However, ethyl acetate is not as efficient as ether in the extraction of____ or _____ from the stool.

Answer 41

cestode eggs and Giardia cysts fat or mucoidal material

Question 42

Formalin is an all purpose fixative. A_____ concentration is recommended for ***protozoan cysts,*** while a ____concentration is recommended for ***helminth eggs and larvae.***

Answer 42

5% 10%

Question 43

Formalin solution may be buffered with_______ to preserve the morphological characteristics of the organisms. Preserved stool can be concentrated using___________

Answer 43

sodium phosphate formalin-ether/ ethyl acetate concentration technique (FECT)