Parasites/Fungi — Flashcards

Flashcard 51: Which fungus is classically identified by an encapsulated yeast with a wide clear halo on **India ink** preparation? _____

Answer: Cryptococcus neoformans

Extra: India ink is used to visualize the thick polysaccharide capsule of Cryptococcus neoformans. The capsule excludes the ink, creating a clear halo around the yeast cell. Latex agglutination for capsular antigen is a more sensitive and specific test.

Flashcard 52: Pediculus humanus and Phthirus pubis are _____ that cause intense pruritus

Answer: lice

Flashcard 53: _____ include Protozoa and Fungi

Answer: Eukaryotes

Flashcard 54: The bronchoalveolar lavage (BAL) sample is stained with _____ to identify the fungus Pneumocystis jirovecii in Pneumocystis Pneumonia

Answer: methenamine silver

Flashcard 55: Which fungus forms **germ tubes** (true hyphae) when incubated in serum at 37°C? _____

Answer: Candida albicans

Extra: *Candida albicans* is a polymorphic fungus. It forms yeast and pseudohyphae at 20°C, but forms germ tubes (true hyphae) at 37°C (the "opposite" of thermal dimorphism seen in systemic mycoses).

Flashcard 56: What infectious cause of esophagitis presents as white pseudomembranes? _____

Answer: Candida

Flashcard 57: The India Ink stain is mostly used to identify the fungus _____

Answer: Cryptococcus neoformans

Flashcard 58: Coccidioides is found in the _____ United States

Answer: Southwestern

Extra: Also known as "desert rheumatism", this fungus is endemic to dry areas in the Southwestern US (e.g. San Joaquin Valley in California, Arizona).

Flashcard 59: Paracoccidioidomycosis are _____ RBCs

Answer: larger than

Flashcard 60: Pneumocystis jirovecii has a(n) _____ transmission

Answer: respiratory