Clinical Utilization of DiaSorin Molecular Polymerase Chain Reaction in Pneumocystis Pneumonia

• Authors: Gregory L Damhorst, Emory University; Kari J Broder, Emory University; Elizabeth C Overton, Emory Healthcare; Ronelio Rara, Emory Healthcare; Lindsay Busch, Emory University; Eileen Burd, Emory University; Andrew Webster, Emory University; Colleen Kraft, Emory University; Ahmed Babiker, Emory University
• Journal Title: OPEN FORUM INFECTIOUS DISEASES
• Volume: Volume 9, Number 1
• Publisher: OXFORD UNIV PRESS INC | 2022-01-01, Pages ofab634-ofab634
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1093/ofid/ofab634
• Subjects: Health Sciences, Pathology; Health Sciences, Medicine and Surgery
• Keywords: Science & Technology; Life Sciences & Biomedicine; Immunology; Infectious Diseases; Microbiology; diagnosis; Pneumocystis jirovecii; pneumonia; quantitative PCR; REAL-TIME PCR; JIROVECII PNEUMONIA; QUANTITATIVE PCR; BRONCHOALVEOLAR LAVAGE; ASSAY; COLONIZATION; DIFFERENTIATION; DIAGNOSIS

Abstract

Background: Pneumocystis jirovecii polymerase chain reaction (PCR) testing is a sensitive diagnostic tool but does not distinguish infection from colonization. Cycle threshold (CT) may correlate with fungal burden and could be considered in clinical decision making. Clinical use of PCR and significance of CT values have not previously been examined with the DiaSorin Molecular platform. Methods: Retrospective review of P jirovecii PCR, CT values and clinical data from 18 months in a multihospital academic health system. The diagnostic performance of PCR with respect to pathology and correlation of CT with severity were examined. Results: Ninety-nine of 1006 (9.8%) assays from 786 patients in 919 encounters were positive. Among 91 (9.9%) encounters in which P jirovecii pneumonia (PJP) was treated, 41 (45%) were influenced by positive PCR. Negative PCR influenced discontinuation of therapy in 35 cases. Sensitivity and specificity of PCR were 93% (95% CI, 68%-100%) and 94% (95% CI, 91%-96%) with respect to pathology. CT values from deep respiratory specimens were significantly different among treated patients (P = .04) and those with positive pathology results (P <. 0001) compared to patients not treated and those with negative pathology, respectively, and was highly predictive of positive pathology results (area under the curve = 0.92). No significant difference was observed in comparisons based on indicators of disease severity. Conclusions: Pneumocystis jirovecii PCR was a highly impactful tool in the diagnosis and management of PJP, and use of CT values may have value in the treatment decision process in select cases. Further investigation in a prospective manner is needed.