Molecular diagnosis of Pneumocystis pneumonia in immunocompromised patients

Hélène Guegan (1, 2) , Florence Robert-Gangneux (1)

1 Irset - Institut de recherche en santé, environnement et travail
2 EHESP - École des Hautes Études en Santé Publique [EHESP]

Purpose of review: Pneumocystis pneumonia (PCP) is a frequent opportunistic infection associated with a high mortality rate. PCP is of increasing importance in non-HIV immunocompromised patients, who present with severe respiratory distress with low fungal loads. Molecular detection of Pneumocystis in broncho-alveolar lavage (BAL) has become an important diagnostic tool, but quantitative PCR (qPCR) needs standardization.Recent findings: Despite a high negative predictive value, the positive predictive value of qPCR is moderate, as it also detects colonized patients. Attempts are made to set a cut-off value of qPCR to discriminate between PCP and colonization, or to use noninvasive samples or combined strategies to increase specificity.Summary: It is easy to set a qPCR cut-off for HIV-infected patients. In non-HIV IC patients, a gain in specificity could be obtained by combining strategies, that is, qPCR on BAL and a noninvasive sample, or qPCR and serum beta-1,3-D-glucan dosage.

Mots clés: immunocompromised patients; molecular diagnosis; PCR; Pneumocystis jirovecii; Pneumocystis pneumonia

Domaines: Maladies infectieuses; Pneumologie et système respiratoire

Hélène Guegan, Florence Robert-Gangneux. Molecular diagnosis of Pneumocystis pneumonia in immunocompromised patients. Current Opinion in Infectious Diseases, 2019, 32 (4), pp.314-321. ⟨10.1097/QCO.0000000000000559⟩. ⟨hal-02153616⟩