Clinical Parasitology: Techniques in Fecal Detection

What is the purpose of using the direct wet mount technique in fecal detection?

• To speed up the detection process

• To enhance the color contrast of parasites

• To reduce the risk of contamination

• To observe live motile parasites without staining

Describe the process of preparing a fecal smear for examination under a microscope.

• The slide is examined without adding any solution

• A small amount of feces is placed on a glass slide, a drop of saline or iodine solution is added, a coverslip is placed, and the slide is examined under a microscope.

• The coverslip is placed before adding feces

• Feces is spread directly on the microscope lens

What is the significance of using iodine in the fecal flotation technique?

• Iodine prevents the eggs from floating

• Iodine helps in dissolving the fecal material

• Iodine neutralizes the fecal sample

• Iodine stains the parasites for better visibility

Explain the role of the Baermann technique in detecting parasitic larvae in fecal samples.

• The Baermann technique involves staining fecal samples to visualize parasitic larvae

• The Baermann technique is used to detect parasitic larvae in fecal samples by allowing the larvae to migrate out of the feces and into water for collection and identification.

• The Baermann technique relies on PCR amplification to identify parasitic larvae

• Parasitic larvae in fecal samples are detected using a centrifugation technique

How does the McMaster technique help in quantifying parasite eggs in fecal samples?

• The McMaster technique relies on genetic analysis to quantify parasite eggs in fecal samples

• The McMaster technique measures the weight of fecal samples to estimate parasite egg concentration

• The McMaster technique involves using a microscope to directly observe parasite eggs in fecal samples

• The McMaster technique helps in quantifying parasite eggs in fecal samples by using a counting chamber to concentrate and count the eggs.

Discuss the advantages of using the zinc sulfate centrifugal flotation technique in fecal detection.

• The zinc sulfate centrifugal flotation technique is less accurate than traditional methods

• It is ineffective in detecting certain types of parasites

• This technique is time-consuming and requires specialized equipment

• The zinc sulfate centrifugal flotation technique is advantageous in fecal detection due to its high sensitivity for detecting parasite eggs and cysts.

What are the limitations of the formalin-ethyl acetate concentration technique in fecal examination?

• Inability to detect certain parasites like Strongyloides stercoralis, poor sensitivity for detecting protozoa cysts, and potential distortion of parasite morphology.

• No distortion of parasite morphology

• Ability to detect all parasites including Strongyloides stercoralis

• Enhanced sensitivity for detecting protozoa cysts

Compare and contrast the sedimentation and flotation techniques in fecal parasite detection.

• The brand of microscope used for examination

• The temperature at which the techniques are performed

• The main difference between sedimentation and flotation techniques in fecal parasite detection is the method of separating parasites from fecal material.

• The color of the solution used

What precautions should be taken when performing fecal detection techniques to avoid contamination?

• Use appropriate PPE, work in a clean area, use sterile equipment, and dispose of waste properly.

• Perform the technique outdoors, work with bare hands, use contaminated equipment, and dispose of waste in a public trash can.

• Use inappropriate PPE, work in a dirty area, use non-sterile equipment, and dispose of waste in a nearby river.

• Wear sunglasses, work in a dark room, use rusty equipment, and throw waste on the floor.

How can the Kato-Katz technique be used to detect helminth eggs in fecal samples?

• Using a PCR-based method

• Counting the number of bacteria present

• Visual inspection without filtering

• The Kato-Katz technique can be used to detect helminth eggs in fecal samples by filtering a small amount of the sample through a template, examining the filtered material under a microscope, and counting the eggs found.