Pneumocystis Flashcards
What forms pneumocystis jirovecii found in?
Trophozoite and cyst forms.
What is the causative organism of pneumocystis?
Pneumocystis jirovecii
What is a trophozoite?
A protozoan of a vegetative form as distinguished from one of a reproductive or resting form.
What class of organism is pneumocystis jirovecii thought to be closely related to?
Fungi.
How is P.jirovecii spread?
Airborne. Spores thought to play a role.
What does P.jirovecii cause?
Pneumonia. LRTI.
Who gets pneumonia caused by P.jirovecii?
Immunocompromised:
- HIV/AIDS
- malnourished children
- chemotherapy patients
- patients on steroids or immunosuppressives
Outline the pathogenesis of P.jirovecii.
Organism attaches to type 1 alveolar cells > if immunocompromised > alveoli filled with foamy exudate
What features are severe cases of pneumocystis pneumonia associated with?
Hyaline membranes
Interstitial fibrosis
Edema
What is another name for type1 pneumocytes?
Squamous alveolar cells.
What are the clinical features of pneumocystis pneumonia?
Fever. SOB. Non-productive cough Tachycardia Tachypnoea
What can one expect from the blood gas analysis of a patient with pneumocystis pneumonia?
Hypoxia.
What might one expect to see on a cxr of a pneumocystis pneumonia patient?
Ground grass appearance
What methods are used to diagnose pneumocystis pneumonia?
Microscopy:
- immunoflourescence using labelled monoclonal antibodies
PCR:
- possible false-positives due to detectin of colonizing organisms
Treatment for pneumocystis pneumonia?
Co-trimoxazole in high doses.
