Laboratory Diagnosis of Parasitic Infection

These flashcards cover key concepts related to the laboratory diagnosis of parasitic infections, including specimen collection, examination techniques, and preservation methods.

What is the main focus of laboratory diagnosis for parasitic infection?

Detection and Identification of the parasite and the morphological stage in its life cycle.

What are common clinical specimens used for parasitic diagnosis?

Faeces, Blood, Urine, Bone Marrow, Lymph Nodes.

What does the OVA AND PARASITES (O & P) procedure typically include?

It includes Direct wet smear, Concentration technique, and Permanent stained smear.

What is the preferred stool type for the stool examination process?

The second-half of normally passed formed or diarrheic stool.

What is the typical stool collection protocol for parasitic diagnosis?

Collect normally on the 1st and 2nd day, then use a cathartic agent on the 3rd day.

What should be avoided in stool collection to prevent interference with detection?

Certain medications like barium, bismuth, laxatives, and anti-diarrheals.

What is the maximum time for examining liquid stool at room temperature?

Within 30 minutes.

What does the macroscopic examination of stool involve?

Examining for scolices and proglottids of cestodes, adult nematodes, and trematodes, as well as the stool's consistency and color.

What does a positive result of E. histolytica indicate in terms of microscopic examination?

0-1/hpf is considered positive.

What is the purpose of the Kato-Katz Method in egg counting procedures?

It uses a measured amount of stool to determine the total egg count multiplied by a factor for eggs per gram of feces.

How should stool samples be fixed for preservation?

Using formalin in a ratio of 1 part stool to 3 parts fixative.

What is the significance of the Baermann Funnel Technique?

It cultures stool positive for hookworm ova or Strongyloides stercoralis to develop filariform larvae.

What is an Enterotest or String test used for?

To examine mucoidal material from the stomach for parasites.

What is the recommended method by WHO for assessing the intensity of infection with specific parasites?

The Kato-Katz Method.

What are common fixatives used for stool preservation?

Formalin, Schaudinn's Solution, Polyvinyl Alcohol (PVA), Sodium Acetate Formalin (SAF).

What does a Rectal Biopsy reveal in parasitology?

The presence of deposited eggs of Schistosoma japonicum.

What are typical microscopic examination methods for identifying parasites?

Direct wet mount, concentration procedures, and permanent stained smears.

What is important to note about storing stools for parasitic examination?

Stools should be kept at 3-5°C, but refrigeration kills trophozoites.