title: Blood (1->3)-beta-D-glucan as a diagnostic test for HIV-related Pneumocystis jirovecii pneumonia.
abstract: (See the editorial commentary by Morris and Masur, on pages 203-204.)
  
  
  BACKGROUND
  Improved noninvasive diagnostic tests for Pneumocystis jirovecii pneumonia (PCP) are needed. We evaluated the test characteristics of plasma (1 → 3)-β-D-glucan (β-glucan) for HIV-related PCP among a large group of patients presenting with diverse opportunistic infections (OIs).
  
  
  METHODS
  The study population included all 282 participants in AIDS Clinical Trials Group A5164, a study of early versus deferred antiretroviral therapy in conjunction with initial therapy of acute OIs. Baseline plasma samples were assayed for β-glucan, with standard assay reference values defining ≥ 80 pg/mL as positive. Before this analysis, diagnosis of PCP was independently adjudicated by 2 study investigators after reviewing reports from study sites.
  
  
  RESULTS
  A total of 252 persons had a β-glucan result that could be analyzed, 173 (69%) of whom had received a diagnosis of PCP. Median β-glucan with PCP was 408 pg/mL (interquartile range [IQR], 209-500 pg/mL), compared with 37 pg/mL (IQR, 31-235 pg/mL) without PCP (P < .001). The sensitivity of β-glucan dichotomized at 80 pg/mL for the diagnosis of PCP was 92% (95% confidence interval [CI], 87%-96%), and the specificity was 65% (95% CI, 53%-75%); positive and negative predictive values were 85% (95% CI, 79%-90%) and 80% (95% CI, 68%-89%) respectively, based on the study prevalence of 69% of patients with PCP. Rates of abnormal lactate dehyrogenase levels did not differ significantly between those with and without PCP.
  
  
  CONCLUSIONS
  Blood (1 → 3)-β-D-glucan is strongly correlated with HIV-related PCP. In some clinical centers, this may be a more sensitive test than the induced sputum examination and could reduce the need for both bronchoscopy and empirical therapy of PCP.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA. psax@partners.org
authors.forename: Paul E
authors.initials: PE
authors.lastname: Sax
authors.forename: Lauren
authors.initials: L
authors.lastname: Komarow
authors.forename: Malcolm A
authors.initials: MA
authors.lastname: Finkelman
authors.forename: Philip M
authors.initials: PM
authors.lastname: Grant
authors.forename: Janet
authors.initials: J
authors.lastname: Andersen
authors.forename: Eileen
authors.initials: E
authors.lastname: Scully
authors.forename: William G
authors.initials: WG
authors.lastname: Powderly
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Zolopa
mesh_terms: D000328:Adult; D003955:Diagnostic Tests, Routine / Q000379:methods*; D005260:Female; D015658:HIV Infections / Q000150:complications*; D006801:Humans; D008297:Male; D010949:Plasma / Q000737:chemistry / Q000276:immunology; D045363:Pneumocystis carinii / Q000737:chemistry* / Q000276:immunology; D011020:Pneumonia, Pneumocystis / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011509:Proteoglycans; D012680:Sensitivity and Specificity; D047071:beta-Glucans / Q000097:blood* / Q000276:immunology
chemical_list: D011509:Proteoglycans; D047071:beta-Glucans; C010770:polysaccharide-K