Neutropenia‐related aspergillosis in non‐transplant haematological patients hospitalised under ambient air versus purified air conditions.

Background: To reduce the risk of invasive aspergillosis (IA), air purification by high‐efficiency particulate air filtration and laminar air flow (HEPA/LAF) is standard of care in allogeneic blood stem cell transplantation. Its use in non‐transplant haematological patients is inconsistent. Objectives: We sought to assess the incidence and outcome of pulmonary IA in non‐transplant patients with life‐threatening neutropenia by comparing an ambient air hospitalisation period (2008–2011) with a subsequent HEPA/LAF hospitalisation period (2012–2014). Patients and Methods: We compared 204 consecutive patients with acute myeloid leukaemia, acute lymphoblastic leukaemia or aplastic anaemia completing 534 neutropenia‐related hospitalisations under ambient air conditions with 126 such patients completing 437 neutropenia‐related hospitalisations under HEPA/LAF conditions. IA was defined using the 2008 EORTC/MSG criteria. Results: Within a 7‐year study period, we observed one 'proven', three 'probable' and 73 'possible' IAs, most often during acute leukaemia remission induction. Their frequency rose with increasing duration of life‐threatening neutropenia (1–10 days, 1.8%; >40 days, 35.2%) and concomitant severe anaemia (0 days, 3.2%; >20 days, 31.0%). Multiple logistic regression revealed a strong correlation between IA incidence and hospitalisation under HEPA/LAF conditions (odds ratio [OR], 0.368 [95% confidence interval, 0.207–0.654]; p <.001) and duration of neutropenia (OR, 1.043 [1.023–1.062] per day; p <.001) and anaemia (OR, 1.044 [1.008–1.081] per day; p =.016). IA‐associated fatal outcomes were non‐significantly reduced under HEPA/LAF (OR, 0.077 [0.005–1.151]; p =.063). The protective effect of HEPA/LAF was not seen under posaconazole prophylaxis (OR, 0.856 [0.376–1.950]; p =.711). Conclusions: Implementation of HEPA/LAF was associated with a significant reduction in neutropenia‐related IA in non‐transplant haematological patients. [ABSTRACT FROM AUTHOR]