Pneumocystis Flashcards
Identify the characteristics of Pneumocystis that most resemble a protozoan.
- Cyst and trophozoite stage- Protozoa?
- Does not grow on artificial media in the laboratory = protozoa?
Identify the characteristics of Pneumocystis that most resemble a fungus.
DNA sequence
Is pneumocystis jiroveci (formerly P. carinii) fungus or protozoa?
Fungus
What is the treatment for Pneumocystis infections?
Antibacterial agents (SXT- Trimethoprim-sulfamethoxazole), not antifungal or antiparasitic agents.
Which stain is more beneficial for recognizing cyst?
GMS is more beneficial and Giemsa, kinyoun or gram stains are also used but more difficult to recognize
Which stain is more beneficial for recognizing Trophozoites?
Giemsa stain
Describe the appearance of Pneumocystis trophozoites on giemsa stain
Pale blue cytoplasm with small mass of reddish nuclear chromatin
Describe the appearance of Pneumocystis cysts on GMS and Giemsa, kinyoun or gram stain.
- May contain up to 8 intracystic bodies (clock face)
- only cyst WALL stains Black with GMS - crinkled, raisin like, or punched out pingpong ball.
- ONLY intracystic bodies of cysts stain with Giemsa, kinyoun, or gram stains
What is the best specimen to use for Pneumocystis jirvoeci identification?
usually from BAL specimen
Can Pneumocystis infection be found in healthy individuals?
YES (no symptoms)
- Antibodies usually acquired early in life
What is the significance of a diagnosis with Pneumocystis with undiagnosed AIDS patients?
Person who has Pneumocystis will be diagnosed with AIDS. Often first clue to new AIDS patients
Patients populations that are at increased risk for infection with Pneumocystis.
- respiratory transmission
- healthy individuals
What is cause of Pneumocystis?
- cause of pneumonia in immunosuppressed patients
- AIDS/HIV & post transplant immunosuppression, leukemia patients on chemotherapy
- Attaches/destroys alveoli
