PNEUMOCYSTIS

Question 1

• important cause of pneumonia in immunocompromised hosts (HIV infection, organ transplants, hematologic malignancies, receiving high-dose glucocorticoids or immunosuppressive monoclonal antibodies)
• organism is a fungus

Answer 1

Pneumocystis

Question 2

are critical in host defense against Pneumocystis

Answer 2

CD4+ T cells

Question 3

On physical Exam,
• decreased oxygen saturation—at rest or with exertion à severe hypoxemia
• normal chest examination and no adventitious sounds à diffuse rales and
signs of consolidation

Answer 3

Pneumocystis

Question 4

Lab Findings of Pneumocystis

• LDH
• WBC
• Hepatic and Renal Function Test

Answer 4

• Elevated LDH
• Elevated WBC
• Normal hepatic and renal function test

Question 5

• so sensitive that it is difficult to distinguish patients with colonization from those with acute pneumonia due to Pneumocystis.
• More useful for ruling out a diagnosis

Answer 5

PCR Testing

Question 6

Test that is almost 100% sensitive and specific for PCP

Answer 6

bronchoalveolar lavage (BAL) fluid

Question 7

• H&E stain: foamy alveolar infiltrate and a mononuclear interstitial infiltrate (Pathognomonic for PCP)
• lung tissue or pulmonary secretions by highly specific staining of the cyst

Answer 7

transbronchial lung biopsy

Question 8

Factors that influence mortality risk of Pneumocystis

Answer 8

• patient’s age
• degree of immunosuppression as well as comorbidities,
• presence of preexisting lung disease,
• low serum albumin level,
• need for mechanical ventilation,
• development of a pneumothorax

Question 9

First-Choice Agent of Pneumocytosis

Answer 9

TMP-SMX

Question 10

Alternative Tx of pneumocytosis

Answer 10

1. Atovaquone
2. Clindamycin + Primaquine
3. Pentamidine

Question 11

Adjunctive Agent for pneumocytosis

Answer 11

Prednison or methylprednisolone

Question 12

Prophylaxis of Pneumocytosis

First Choice

Answer 12

TMP-SMX