Pneumocystis jiroveci Pneumonia

Pneumocystis jiroveci Pneumonia

Clinical Considerations

  • [A-a] DO2: alveolar-arterial PO₂ gradient
  • PO2: room air arterial oxygen
  • PJP PCR has replaced DFA (no longer available at Scripps)
  • Bronchial wash/BAL samples are preferred over sputum given increased sensitivity
  • Pneumocystis can be a respiratory colonizer; PJP PCR interpretation must incorporate clinical judgment
    • Higher cycle threshold values may correlate with colonization
    • In patients with a compatible clinical syndrome for PJP, higher Beta-D-Glucan values (>200 pg/mL) are associated with clinically significant PJP infections among PCR-positive patients
  • Initiation of treatment should not be deferred by BAL/PCR results, since PJP remains detectable in bronchial secretions for many days after the start of systemic treatment
  • Testing for G6PD deficiency on all patients is recommended to prevent delays in therapy changes

TMP-SMX: GI distress, rash, fever, neutropenia, hyperkalemia, LFT elevation, photosensitivity, increased serum creatinine

Atovaquone: GI distress, fever, LFT elevation, rash

Clindamycin: Rash, diarrhea, C. difficile colitis

Primaquine: GI distress, rash, fever, methemoglobinemia, hemolytic anemia, leukopenia, neutropenia.

Pentamidine: Nephrotoxicity, infusion reactions, hypo/hyperkalemia, hyperglycemia, pancreatitis, arrhythmias (including Torsades de pointes), LFT elevation, hypotension, hypoglycemia, hypocalcemia


  • [A-a] DO2 <35 mmHg and/or PO₂ ≥70 mmHg
  • Symptoms:
    • Increasing exertional dyspnea, with/without cough and sweats
  • [A-a] DO2 ≥35 to <45 mmHg and/or PO₂ ≥60 and <70 mmHg
  • Symptoms:
    • Dyspnea on minimal exertion
    • Occasional dyspnea at rest
    • Fever with/without sweats
  • [A-a] DO2 ≥45 and/or PO₂ <60 mmHg
  • Symptoms:
    • Dyspnea at rest
    • Tachypnea at rest
    • Persistent fever
    • Cough


  • Moderate to Severe PJP and/or
  • Hypoxemia on pulse oximetry

More Information

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