title: Serum (1 → 3) β-D-glucan assay for discrimination between Pneumocystis jirovecii pneumonia and colonization.
abstract: Polymerase chain reaction (PCR) technique is being increasingly used for the microbiological diagnosis of Pneumocystis pneumonia (PCP). As PCR is highly sensitive, it can be positive even in a patient with Pneumocystis colonization. In this study, we evaluated whether the β-d-glucan assay could be used to differentiate between PCP and Pneumocystis jirovecii colonization in immunocompromised patients with pulmonary infiltrates. We retrospectively evaluated data from 166 consecutive patients who underwent bronchoalveolar lavage for the diagnosis of PCP. Serum levels of β-d-glucan in the negative, colonization, probable PCP, and definite PCP groups were 20.2 ± 6.3, 48.8 ± 15.9, 89.9 ± 20.2, 224.9 ± 25.9 pg/mL, respectively. The β-D-glucan levels in the definite PCP group were significantly higher than those in the other 3 groups (p < 0.001). Serum β-d-glucan levels in patients with either definite or probable PCP (173.1 ± 18.8 pg/mL) were significantly greater than those in patients with colonization who had positive PCR results but improved without anti-PCP treatment (p < 0.002). The cut-off level for discrimination was estimated to be 33.5 pg/mL, with which the positive predictive value was 0.925. These results indicate that β-D-glucan is a useful marker to differentiate between PCP and Pneumocystis colonization. A positive β-D-glucan assay result might be a good indication to begin anti-PCP treatment.
authors: Division of Pulmonary Medicine, Keio University School of Medicine, Tokyo, Japan. Electronic address: tasaka@cpnet.med.keio.ac.jp.
authors: Sadatomo
authors: S
authors: Tasaka
authors: Department of Tropical Medicine and Parasitology, Keio University School of Medicine, Tokyo, Japan.
authors: Seiki
authors: S
authors: Kobayashi
authors: Division of Pulmonary Medicine, Keio University School of Medicine, Tokyo, Japan.
authors: Kazuma
authors: K
authors: Yagi
authors: Division of Pulmonary Medicine, Keio University School of Medicine, Tokyo, Japan.
authors: Takahiro
authors: T
authors: Asami
authors: Division of Pulmonary Medicine, Keio University School of Medicine, Tokyo, Japan.
authors: Ho
authors: H
authors: Namkoong
authors: Department of Laboratory Medicine, Keio University School of Medicine, Tokyo, Japan.
authors: Wakako
authors: W
authors: Yamasawa
authors: Division of Pulmonary Medicine, Keio University School of Medicine, Tokyo, Japan.
authors: Makoto
authors: M
authors: Ishii
authors: Center for Infection Control and Infectious Diseases, Keio University School of Medicine, Tokyo, Japan.
authors: Naoki
authors: N
authors: Hasegawa
authors: Division of Pulmonary Medicine, Keio University School of Medicine, Tokyo, Japan.
authors: Tomoko
authors: T
authors: Betsuyaku
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000382:microbiology; D002353:Carrier State / Q000097:blood / Q000175:diagnosis*; D004271:DNA, Fungal / Q000032:analysis*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D008297:Male; D008875:Middle Aged; D045363:Pneumocystis carinii / Q000235:genetics; D011020:Pneumonia, Pneumocystis / Q000097:blood / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011509:Proteoglycans; D012189:Retrospective Studies; D047071:beta-Glucans / Q000097:blood*
chemical_list: D015415:Biomarkers; D004271:DNA, Fungal; D011509:Proteoglycans; D047071:beta-Glucans; C010770:polysaccharide-K
keywords: (1 → 3)-β-d-glucan; Bronchoalveolar lavage; Colonization; Pneumocystis pneumonia; Polymerase chain reaction