Pneumocystis pnuemonia/pneumocystis jirovecii Flashcards
Organism attacks who?
HIV/transplant patients/immunocompromised/malnourished infants/ T cell deficient patients
How does the patient present?
fever, nonproductive cough/dyspnea, fatigue, immunocompromised circumstance, CD4+ count less than 200, oral thrush!, cachectic, low WBC count (<5000), hypoxic, cyanotic
(resembles interstitial pneumonia)
CXR demonstrates?
Ground glass appearance and bilateral patchy infiltrates
Etiology
cysts like or hat shaped, obligate (require oxygen to grow) extracellular fungal
Intracellular or extracellular obligate fungal
extracellular obligate fungal
Where does it grow?
over the surfactant layer of alveolar epithelium not grown in labs
composition of membrane
cholesterol (not ergosterol)
Lab diagnosis
bronchial washing (BAL), lung tissue biopsy, and microscopic exam
organisms that attack –> HIV/transplant patients/immunocompromised/malnourished infants/ T cell deficient patients
PCJ, cmv, MAC-acid fast
1 Staining for PCJ
Grocot Methanamine Silver stain (silver stained cysts in center spaces)
Other stains
Toluidine blue-o stain, calcofluor white stain, Giemsa stain, H&E, fluorescent antibody stain, nucleic acid test(PCR)
pathology
organism attach use MSG to attach to host fibronectin killing type I pneumocytes and causing excessive type II proliferation; this results in alveoli inflammation, filling with foamy fluid –> blocks O2 exchange and gives honeycomb appearance
attachement site
major surface glycoprotein (MSG) attaches to host fibronectin
prophylaxis 1
Trimethoprim-sulfamethoxazole
prophylaxis 2
Dapson + pyrimethamine OR atovoquone
