Diagnostic yield of a bronchoalveolar lavage fluid galactomannan assay in patients with negative serum galactomannan results suspected to have invasive pulmonary aspergillosis

Abstract

Background and objectives: There are limited data in real clinical practice on the diagnostic value of a bronchoalveolar lavage (BAL) fluid galactomannan (GM) assay in patients with suspected invasive pulmonary aspergillosis (IPA) who had negative serum GM results. Thus, we investigated the diagnostic performance of a BAL GM assay in patients with negative serum GM assay results who were suspected to have IPA.

Methods: This retrospective study was performed between May 2008 and April 2019 at a tertiary-care hospital in Seoul, South Korea. All patients with suspected IPA whose serum GM assays revealed negative results who sequentially underwent BAL were enrolled in this study.

Results: A total of 341 patients with suspected IPA including four cases of proven IPA, 38 cases of probable IPA, 107 cases of possible IPA and 192 patients without IPA were enrolled. Of these 341 patients, 107 (31%) with possible IPA were excluded from the final analysis. Of 42 patients with proven and probable IPA who had initial negative serum GM results, 24 (57%) had positive BAL GM results (n = 24) or BAL fungal culture results (n = 8). In addition, BAL revealed evidence of other opportunistic infections including Pneumocystis jirovecii pneumonia (14% [26/190]), cytomegalovirus (CMV) pneumonia (5% [9/188]) and respiratory viral pneumonia (6% [12/193]).

Conclusion: Sequential BAL in patients with suspected IPA who had initial negative serum GM results provided additional diagnostic yield in approximately half of patients with evidence of another co-infection.

Keywords: antifungal agents; aspergillosis; bronchoalveolar lavage; galactomannan; immunocompromised host; invasive fungal infections; invasive pulmonary aspergillosis; opportunistic infection.