Microbiologic Diagnostic Workup of Acute Respiratory Failure with Pulmonary Infiltrates after Allogeneic Hematopoietic Stem Cell Transplantation: Findings in the Era of Molecular- and Biomarker-Based Assays

Abstract

Allogeneic hematopoietic stem cell transplantation (HSCT) recipients frequently develop acute respiratory failure (ARF) with pulmonary infiltrates. Molecular- and biomarker-based assays enhance pathogen detection, but data on their yield in this population are scarce. This was a retrospective single-center study of 156 consecutive HSCT recipients admitted to the intensive care unit (ICU) between May 2013 and July 2017. Findings from a microbiologic diagnostic workup using currently available methods on bronchoalveolar lavage (BAL) and blood samples from 66 patients (age, 58 years [range, 45 to 64]; HSCT to ICU, 176 days [range, 85 to 407]) with ARF and pulmonary infiltrates were analyzed. In 47 patients (71%) a causative pathogen was identified (fungal, n = 28; viral, n = 26; bacterial, n = 18). Polymicrobial findings involving several pathogen groups occurred in 20 patients (30%). Culture (12/16, 75%), galactomannan (13/15, 87%), and Aspergillus-PCR (8/9, 89%) from BAL but not serum galactomannan (6/14, 43%) helped to diagnose invasive aspergillosis (n = 16, 24%). Aspergillus-PCR detected azole resistance in 2 cases. Mucorales was found in 7 patients (11%; BAL culture, n = 6; Mucorales-PCR, n = 1). Patients with identified pathogens had higher Simplified Acute Physiology Score II scores (P = .049) and inferior ICU survival (6% versus 37%, P < .01), which largely related to the presence of an invasive fungal infection. Eight patients (12%) had 1 or more viruses with uncertain lung pathogenicity as the sole microbiologic finding. A diagnostic microbiologic workup incorporating molecular- and biomarker-based assays identified pathogens in most HSCT recipients with ARF and pulmonary infiltrates admitted to the ICU. Implications of polymicrobial infection and pathogen patterns in these patients warrant further investigation.

Evaluation of MucorGenius® mucorales PCR assay for the diagnosis of pulmonary mucormycosis

“…Although considered to be an uncommon IFD (3), the incidence of mucormycosis among patients with hematological malignancies, e.g. in allogeneic hematopoietic stem cell transplantation (HSCT), is high (4), reaching 11% (7/66) for HSCT recipients admitted to an intensive care unit (ICU) (5). The incidence of mucormycosis has significantly increased during the last two decades in Europe (6)(7)(8), as illustrated by a French national retrospective study, reporting an increase from 0.7 to 1.2 per million over a ten-year period (1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006) (7), with high mortality, ranging from 50 to 100% (4).…”

Influence of antifungal prophylaxis on the occurrence of fungal infections in patients undergoing allogeneic transplantation

“…U Nemačkoj je, u periodu od 2013. do 2017. godine, rađeno retrospektivno istraživanje na 156 primalaca aloTMĆ-a, na odeljenju intenzivne nege [21]. Standardni dijagnostički testovi izvedeni na bronhoalveolarnom lavatu (BAL) obuhvatali su konvencionalnu kulturu za bakterije i gljivice, direktnu mikroskopiju, galaktomanan i PCR testiranje za otkrivanje gljivičnih, bakterijskih i virusnih patogena.…”

“…In Germany, in the period between 2013 and 2017, a retrospective study was performed on 156 intensive care patients who were recipients of allo-SCT [21]. Standard diagnostic tests performed on bronchoalveolar lavage (BAL) specimens included conventional bacteria and fungi culture testing, direct microscopy, galactomannan and PCR testing for detecting fungal, bacterial and viral pathogens.…”

Infektionen bei hämatologisch-onkologischen Patienten auf der Intensivstation

“…In der radiologischen Bildgebung ist die CT dem konventionellen Röntgenbild deutlich überlegen [20]. Insbesondere nach CT-geführter fiberoptischer Bronchoskopie mit bronchoalveolärer Lavage gelingt in der Mehrzahl der Fälle die Identifikation eines kausalen Pathogens [21] (▶ Abb. 4).…”