Parasitology practical

What is the stage represented by a hydatid cyst?

Cystic larval stage of Echinococcus.

What are the layers of the hydatid cyst wall?

Outer thick laminated layer and inner cellular germinal layer.

What does the hydatid cyst contain?

Multiple scolices and brood capsules attached to the wall or floating in fluid.

Which intradermal test is used for hydatid disease diagnosis?

Casoni test.

What is the parasitological value of hydatid fluid?

It contains antigen used for diagnosis.

Hydatid fluid antigen is used in which tests?

Casoni test, ELISA, IHA, indirect fluorescent antibody test.

Mention two confirmatory diagnostic methods for hydatid cyst.

Aspirate from the cyst and surgical removal with histopathology.

What is hydatid sand?

Detached scolices, brood capsules, and daughter cysts floating in hydatid fluid.

Which intradermal test is used for hydatid sand diagnosis?

Casoni test.

What stain is commonly used for hydatid sand elements?

Ziehl–Neelsen stain.

Mention diagnostic methods for hydatid disease.

Cyst aspiration, sputum examination, serology, Casoni test, radiology.

What are the special characters of Entamoeba histolytica trophozoite?

Irregular outline with pseudopodia, one nucleus, food vacuoles, and RBCs.

What is the parasitological value of Entamoeba histolytica trophozoite?

Diagnostic stage for amoebiasis.

What is the best diagnostic sample for a developed amoebic abscess?

Aspirated pus or biopsy from the base of the abscess.

What is the best biopsy site in amoebic abscess?

Base of the abscess.

What are the parasitological values of Entamoeba histolytica cyst?

Infective stage and diagnostic stage for intestinal amoebiasis.

What are the special characters of Entamoeba histolytica cyst?

Smooth refractile wall, 2–4 nuclei, rod-like chromatoid bodies.

Which parasitic stage is detected in amoebic abscess aspirate?

Entamoeba histolytica trophozoite.

What are the best permanent stains for Entamoeba histolytica?

Trichrome or iron-hematoxylin stain.

What is the best stool concentration technique for Entamoeba cyst?

Floatation technique using zinc sulphate.

What are the special characters of Schistosoma haematobium egg?

Large egg with terminal spine, no operculum, contains miracidium.

What is the parasitological value of Schistosoma haematobium egg?

Diagnostic stage in urine.

How is egg viability of Schistosoma haematobium examined?

Hatching test.

What are the characters of Schistosoma mansoni egg?

Large egg with lateral spine, no operculum, contains miracidium.

What is the parasitological value of Schistosoma mansoni egg?

Diagnostic stage in stool.

What is the best stool concentration technique for Schistosoma mansoni egg?

Sedimentation technique.

What is the most commonly used solution in sedimentation technique?

Formalin ethyl acetate.

What is the parasitological value of Schistosoma cercaria?

Infective stage.

What are the special characters of Schistosoma cercaria?

Body with oral and ventral suckers, penetration glands, and bifid tail.

What are the special characters of Ascaris egg?

Oval brown egg with immature ovum and two coverings.

What are the coverings of Ascaris egg?

Outer albuminous mammillated layer and inner thick shell.

What are the parasitological values of Ascaris egg?

Diagnostic stage; mature larvated egg is infective stage.

What are the special characters of Toxocara egg?

Rounded yellowish-brown egg with pitted shell and immature ovum.

How is human toxocariasis confirmed?

Serological tests: IHA, IFA, ELISA.

What is the parasitological value of Toxocara egg?

Mature larvated egg is infective stage.

What parasite egg is ovoid, golden brown with operculum?

Paragonimus westermani egg.

What are the special characters of Paragonimus westermani egg?

Ovoid, thick shell, flat operculum, immature miracidium.

What is the parasitological value of Paragonimus westermani egg?

Diagnostic stage for paragonimiasis.

What are the best diagnostic materials for Paragonimus westermani egg?

Sputum, pleural fluid aspirate, and stool.

What parasite causes allergic rhinitis and allergic bronchial asthma?

House dust mite.

Where can house dust mite be detected?

Dust, carpets, mattresses, air-conditioner filters.

What is the best diagnostic technique for house dust mite allergy?

Allergen panel test based on type IV hypersensitivity.

What parasite stage is Toxoplasma gondii tachyzoites in pseudocyst?

Tachyzoite stage in pseudocyst.

What pulmonary disease is caused by Toxoplasma gondii?

Pneumonitis.

In which patients is toxoplasma pneumonitis common?

Immunocompromised patients.

What are the best diagnostic techniques for toxoplasmosis?

Serology (ELISA IgM or rising IgG) and lymph node biopsy.

What parasite stages are seen in Plasmodium falciparum infection?

Gametocytes and multiple ring forms.

What pulmonary diseases are caused by Plasmodium falciparum?

ALI, ARDS, pulmonary edema.

In which patients are pulmonary complications of malaria common?

Pregnant females and non-immune individuals.

What are the best diagnostic techniques for malaria?

Blood film examination and chest X-ray.

What parasite stage is Cryptosporidium oocyst?

Oocyst stage.

What pulmonary disease is caused by Cryptosporidium?

Lung inflammation or localized infection.

In which patients is pulmonary cryptosporidiosis common?

Immunocompromised patients.

What is the best staining technique for Cryptosporidium?

Modified Ziehl–Neelsen stain.

What specimens are optimal for diagnosing Cryptosporidium?

Sputum or stool samples.