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Low Titer Pneumocystis jirovecii Infections: More than Just Colonization?

Alexander Prickartz1, Jessica Lüsebrink2, Soumaya Khalfaoui3

  • 1Lungenklinik Merheim, Kliniken der Stadt Köln gGmbH, Universität Witten-Herdecke, Alfred-Herrhausen-Straße 50, Witten 58448, Germany. Alexander.prickartz@malteser.org.

Journal of Fungi (Basel, Switzerland)
|January 30, 2018
PubMed

Insights

Pneumocystis jirovecii colonization may indicate infection in immunocompetent individuals. Successful antibiotic treatment of these patients suggests mild P. jirovecii infections occur beyond pneumonia.

Area of Science:

  • Medical Mycology
  • Infectious Diseases
  • Pulmonology

Background:

  • Non-pneumonia Pneumocystis jirovecii colonization is common in immunocompetent individuals.
  • The clinical significance of low-titer P. jirovecii detections requires further investigation.

Purpose of the Study:

  • To determine if low-titer P. jirovecii detections in immunocompetent patients represent more than simple colonization.
  • To investigate the impact of P. jirovecii detection on clinical outcomes in immunocompetent individuals.

Main Methods:

  • Retrospective analysis of fully immunocompetent patients with P. jirovecii qPCR testing.
  • Inclusion criteria: no immunosuppressive therapy, regular antibody titers, no acquired/inherited/autoimmune diseases, and complete medical records.
  • Identification of patients with P. jirovecii colonization and successful antibiotic treatment.

Main Results:

  • Thirty fully immunocompetent patients with P. jirovecii colonization were identified.
  • These patients presented with milder symptoms than pneumonia, including chronic cough and recurrent pulmonary infections.
  • All 30 patients showed symptom resolution after successful cotrimoxazole treatment for P. jirovecii.

Conclusions:

  • The successful treatment of P. jirovecii in these patients supports the hypothesis of mild infections in immunocompetent individuals.
  • P. jirovecii may cause symptomatic, non-pneumonia infections in immunocompetent hosts.
  • Further research is warranted to understand the clinical spectrum of P. jirovecii in immunocompetent populations.
Keywords:
PCPPneumocystis jiroveciichronic coughchronic infectioncolonizationpneumoniasuccessful recovery

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