RESUMO
BACKGROUND: The role of culture-independent techniques (galactomannan, (1-3)-ß-d-glucan) in the early diagnosis of invasive fungal diseases (IFD) is well assessed in hematological patients, but there are no clear conclusions in patients with chronic obstructive pulmonary disease (COPD). AIMS: To study the usefulness of nonculture-based techniques in the diagnosis of IFD in COPD-patients at risk for IFD. METHODS: A prospective observational study based on monitoring COPD patients at risk for IFD during 2007-2010 was carried out. The presence of galactomannan, (1-3)-ß-d-glucan and an indirect immunofluorescence of Candida albicans germ tube specific antibodies (CAGTA) were performed. RESULTS: Among 43 COPD patients, 16 (37.2%) were diagnosed with IFD: seven cases were proven IFD (five invasive candidemia - IC, one invasive aspergillosis - IA and a rhinocerebral zygomycosis) and nine probable IFD (seven IA and two IC). In the diagnosis of IC and IA, the negative predictive value (NPV) of (1-3)-ß-d-glucan was 100%. Regarding CAGTA in IC, NPV was 96.2%. Finally, NPV of galactomannan in IA was 91.2%. The area under the ROC curve for (1-3)-ß-d-glucan in IC and for the rest of the IFD cases was 0.86 (95% CI, 0.79-0.93) and 0.60 (95% CI, 0.43-0.77), for CAGTA in IC was 0.83 (95% CI, 0.74-0.91) and for galactomannan in IA was 0.71 (95% CI, 0.56-0.85). Positive (1-3)-ß-d-glucan preceded the growth of Candida (average of 1.7 days) in blood culture. CONCLUSIONS: In COPD patients at risk for IFD the assayed techniques are especially useful to rule out the presence of IFD.
