Routine comprehensive Aspergillus screening of bronchoalveolar lavage samples in lung transplant recipients

Abstract

Background Invasive aspergillosis is a significant cause of morbidity and mortality in lung transplant recipients (LTRs). Early diagnosis may improve outcome, yet is challenging. We assessed the diagnostic yield of a routine, comprehensive, prospectively employed Aspergillus screening strategy in LTRs. Methods During a 6‐month period, all bronchoalveolar lavage (BAL) samples (including post‐transplant surveillance) obtained from LTRs at our center were routinely tested for Aspergillus PCR, galactomannan (GM), and fungal culture. Invasive aspergillosis (IA) was defined using EORTC/MSG and ISHLT criteria for proven and probable aspergillosis. Results Ninety‐five consecutive BAL samples were tested. PCR, GM, and fungal culture were positive in 28.4%, 30.6%, and 7.4%, respectively. Five cases of IA (two proven, three probable) were identified. Fungal culture failed to detect 40% of IA cases, which were detected by a positive PCR and/or GM. However, the majority of positive PCR samples represented colonization (59.3%). Sensitivity of PCR, GM, and culture for IA was 80%, 60%, and 60%, respectively, and specificity was 74%, 71%, and 96%. Conclusions In LTRs, a routine prospectively employed screening strategy in which all BAL samples were screened for Aspergillus PCR and GM, detected aspergillosis cases that were otherwise missed by a false‐negative fungal culture, but resulted in more cases of colonization being detected. Clinical judgment is thus warranted to avoid unnecessary treatment of colonization.

Reduced Community-acquired Respiratory Virus Infection, but Not Non–virus Infection, in Lung Transplant Recipients During Government-mandated Public Health Measures to Reduce COVID-19 Transmission

“…In lung transplant patients, Aspergillus galactomannan has a sensitivity of 60% but is often positive in the absence of invasive aspergillosis, suggesting colonization. 13 None of the patients in our study were diagnosed with invasive aspergillosis. Further study is warranted to determine the full relevance of these findings.…”

Utility of microbiologic testing in surveillance bronchoscopy following lung transplantation: A retrospective cohort study

“…Aspergillus is one of the most common posttransplant fungal infections, with an incidence of 6.2%, carrying with it a high risk of morbidity and mortality 16–20 . Identification of these infections can be challenging, as fungal cultures have limited sensitivity, and BAL galactomannan has improved sensitivity but limited specificity for invasive disease 21 . There is a paucity of literature evaluating the utility of fungal screening in SB.…”

“…[16][17][18][19][20] Identification of these infections can be challenging, as fungal cultures have limited sensitivity, and BAL galactomannan has improved sensitivity but limited specificity for invasive disease. 21 There is a paucity of literature evaluating the utility of fungal screening in SB.…”

Diagnostic performance of mycological tests for invasive pulmonary aspergillosis in non-haematological patients: protocol for a systematic review and meta-analysis

“…For example, the sensitivities of the serum tests of GM, BDG and PCR range from 11% to 80% which increase to 44%-90% when tested in bronchoalveolar lavage (BAL) fluid for the non-haematological patients. [18][19][20][21][22][23] Recent novel tests such as LFD and LFA appear to have better results, with sensitivities of 77%-94% and specificities of 81%-92% in patients with non-haematological diseases. 24 25 Moreover, the EORTC/MSG definitions have been recognised as diagnostic standards for IPA; however, other reference criteria including AspICU algorithm and Bulpa definition have been used, 26 27 which may impact the diagnostic yields for mycological tests.…”

“…Current available studies generally had small sample sizes, and the diagnostic yields of tests varied. For example, the sensitivities of the serum tests of GM, BDG and PCR range from 11% to 80% which increase to 44%–90% when tested in bronchoalveolar lavage (BAL) fluid for the non-haematological patients 18–23. Recent novel tests such as LFD and LFA appear to have better results, with sensitivities of 77%–94% and specificities of 81%–92% in patients with non-haematological diseases 24 25.…”