A misleading false-negative result of Pneumocystis real-time PCR assay due to a rare punctual mutation: A French multicenter study.

Solène Le Gal (1, 2) , Florence Robert-Gangneux (3, 4) , Yann Pepino (5) , Sorya Belaz (4, 3) , Céline Damiani (6, 7) , Paul Guéguen (8, 9) , Melanie Pitous (5) , Michèle Virmaux (2, 1) , Eloise Lissillour (5) , Laurence Pougnet (5, 2) , Thibaud Guillaud-Saumur (5, 2) , Dominique Toubas (10, 11) , Stephane Valot (12) , Christophe Hennequin (13, 14) , Florent Morio (15) , Lilia Hasseine (16) , Jean-Philippe Bouchara (2) , Anne Totet (17, 18) , Gilles Nevez (1, 2)

1 Laboratoire de Parasitologie et Mycologiede [CHRU Brest]
2 GEIHP - Groupe d'Étude des Interactions Hôte-Pathogène
3 Service de Parasitologie-Mycologie [Rennes]
4 Irset - Institut de recherche en santé, environnement et travail
5 UBO - Université de Brest
6 PERITOX - Périnatalité et Risques Toxiques - UMR INERIS_I 1
7 Laboratoire de parasitologie et de mycologie médicales [CHU Amiens]
8 GGB - Génétique, génomique fonctionnelle et biotechnologies (UMR 1078)
9 Laboratoire de Génétique Moléculaire et d'Histocompatibilité [Brest]
10 MEDyC - Matrice extracellulaire et dynamique cellulaire - UMR 7369
11 CHU Reims - Centre Hospitalier Universitaire de Reims
12 CHU Dijon
13 CIMI - Centre d'Immunologie et des Maladies Infectieuses
14 Service de Parasitologie - Mycologie [CHU Saint-Antoine]
15 CHU Nantes - Centre hospitalier universitaire de Nantes
16 CHU Nice - Centre Hospitalier Universitaire de Nice
17 AGIR - Agents infectieux, résistance et chimiothérapie - UR UPJV 4294
18 CHU Amiens-Picardie

This article describes a previously unreported mutation at position 210 (C210T) of the mitochondrial large subunit ribosomal RNA (mtLSUrRNA) gene of Pneumocystis jirovecii, which led to a false-negative result of a real-time polymerase chain reaction (PCR) assay. Since the aforementioned real-time PCR assay is widely used in France, a French multicenter study was conducted to estimate the mutation frequency and its potential impact on the routine diagnosis of Pneumocystis pneumonia (PCP). Through analysis of data obtained from eight centers, the mutation frequency was estimated at 0.28%. This low frequency should not call into question the routine use of this PCR assay. Nonetheless, the occurrence of the false-negative PCR result provides arguments for maintaining microscopic techniques combined to PCR assays to achieve PCP diagnosis.

Keywords: PCP; Real time-PCR; mutation; Pneumocystis jirovecii; TaqMan® MGB probe

Domains: Life Sciences [q-bio]; Ecology, environment

Solène Le Gal, Florence Robert-Gangneux, Yann Pepino, Sorya Belaz, Céline Damiani, et al.. A misleading false-negative result of Pneumocystis real-time PCR assay due to a rare punctual mutation: A French multicenter study.. Medical Mycology, 2017, 55 (2), pp.180-184. ⟨10.1093/mmy/myw051⟩. ⟨hal-01477200⟩