The performance of bronchoalveolar lavage Aspergillus PCR testing in solid organ transplant recipients with invasive pulmonary aspergillosis.

Background: Invasive aspergillosis affects solid organ transplant (SOT) recipients, carrying a high risk of mortality and morbidity in this population. Rapid and accurate diagnosis is essential to ensure the initiation of correct antifungal therapy. We aimed to evaluate the performance of the bronchoalveolar lavage (BAL) Eurofins Viracor Aspergillus PCR (AspPCR) in diagnosing invasive pulmonary aspergillosis (IPA) in SOT recipients.

Methods: We conducted a multicenter retrospective study of SOT recipients in Arizona from February 2019 to December 2022 who had AspPCR done at the time of the clinical encounter. Probable IPA was defined as a positive BAL culture with Aspergillus spp. with clinical and imaging findings of IPA per EORTC/MSGERC criteria.

Results: Ninety-nine SOT recipients with 131 encounters with BAL AspPCR testing were included. The median age was 66, the majority were White, non-Hispanics (60%), and males (66%). Among the participants, 93 lung transplant recipients with 87 of the encounters received antifungal prophylaxis active against Aspergillus spp. Sixty-four encounters had BAL galactomannan (GM), all of which had BAL GM <1 OD, and one case had a serum GM of 10 OD. Nine cases met the definition of IPA. The sensitivity of the BAL AspPCR was 67% (95% CI 30%-93%), and the specificity was 98% (95% CI 93%-99%).

Conclusion: BAL AspPCR had moderate sensitivity and high specificity in identifying IPA in our cohort of SOT recipients. Further studies in populations with a higher prevalence of IPA are needed to evaluate the performance of this test.