Usefulness of ß-d-Glucan Assay for the First-Line Diagnosis of Pneumocystis Pneumonia and for Discriminating between Pneumocystis Colonization and Pneumocystis Pneumonia

Abstract

According to the immunodepression status, the diagnosis of Pneumocystis jirovecii pneumonia (PjP) may be difficult. Molecular methods appear very sensitive, but they lack specificity because Pj DNA can be detected in Pneumocystis-colonized patients. The aim of this study was to evaluate the value of a serum ß-d-Glucan (BDG) assay for the diagnosis of PjP in a large cohort of HIV-negative and HIV-positive patients, either as a first-line diagnostic test for PjP or as a tool to distinguish between colonization and PjP in cases of low fungal load. Data of Pj qPCR performed on bronchopulmonary specimens over a 3-year period were retrieved retrospectively. For each result, we searched for a BDG serum assay performed within +/−5 days. Among the 69 episodes that occurred in HIV-positive patients and the 609 episodes that occurred in immunocompromised HIV-negative patients, we find an equivalent sensitivity of BDG assays compared with molecular methods to diagnose probable/proven PjP, in a first-line strategy. Furthermore, BDG assay can be used confidently to distinguish between infected and colonized patients using a 80 pg/mL cut-off. Finally, it is necessary to search for causes of false positivity to increase BDG assay performance. BDG assay represents a valuable adjunctive tool to distinguish between colonization and infection.

Candent issues in pneumonia. Reflections from the Fifth Annual Meeting of Spanish Experts 2023

“…In patients unable to endure a bronchoscopy, serum β-D-glucan has a high NPV that allows rule-out PJP in patients with low to moderate grade of suspicion. In fact, Bigot et al propose to do this test prior to bronchoscopy and to avoid it if test result is negative [ 245 ]. Patients with high grade of suspicion may need molecular techniques in respiratory samples.…”

Global prevalence, mortality, and main characteristics of HIV-associated pneumocystosis: A systematic review and meta-analysis

“…Five studies were conducted from the USA [ 50 – 52 , 68 , 73 ]; three studies, each were conducted in South Africa [ 67 , 72 , 90 ], Japan [ 81 , 84 , 85 ], and Thailand [ 61 , 78 , 86 ]; two studies, each were conducted in Iran [ 75 , 80 ], France [ 45 , 66 ], and Mexico [ 40 , 47 ]; one study each was conducted in Ethiopia [ 39 ], Tanzania [ 60 ], Malawi [ 57 ], Spain [ 38 ], Cameroon [ 76 ], India [ 54 ], Taiwan [ 89 ], Zambia [ 79 ], and a study was from five European countries (France, Austria, Belgium, Croatia, Germany) [ 70 ].…”

“…Our random-effects model showed that in twenty-nine eligible studies [ 38 – 40 , 45 , 47 , 50 – 52 , 54 , 57 , 60 , 61 , 66 – 68 , 70 , 72 , 73 , 75 , 76 , 78 – 81 , 84 – 86 , 89 , 90 ], the pooled prevalence of HAP was 35.4% (95% CI:23.8 to 47.9; I 2 : 99.4%) ( Table 2 ). There is a negligible publication bias between studies (intercept: 6.946; 95% CI:-24.750 to 38.642; P = 0.6566).…”

“…The results of the random-effect model showed that in twenty-nine eligible studies [ 38 – 40 , 45 , 47 , 50 – 52 , 54 , 57 , 60 , 61 , 66 – 68 , 70 , 72 , 73 , 75 , 76 , 78 – 81 , 84 – 86 , 89 , 90 ], the pooled prevalence of PCP among the HIV-negative population was 10.158% (95% CI:2 to 25.3; I 2 : 99.9%). Also, analysis of publication bias using the Egger test model indicated an intercept rate of 14.326% (95% CI: -2.023 to 30.675; P = 0.0834)( Table 2 ).…”

Previous corticosteroid exposure associates with an increased Pneumocystis jirovecii pneumonia mortality among HIV-negative patients: a global research network with a follow-up multicenter case-control study

“…(1,3) β-D-glucan is a cell wall component of P jirovecii and has been found to have a heightened sensitivity to diagnose PJP and can be used as an initial screening method. 19 Retrospective studies did not find it a valuable prognostic factor for diagnosis or respiratory burden. 20,21 However, it correlated with bronchoalveolar lavage fungal load in earlier studies.…”