Comparison of PCR and culture based detection of pathogens in bronchoalveolar fluid in neutropenic children

Abstract

Problem: Respiratory tract infections are a frequent complication in neutropenic children and treated with broad spectrum antibiotic therapy. If the clinical situation worsens, we perform a chest CT-scan and bronchoalveolar lavage (BAL) before antifungal treatment is started. The aim of this study was to investigate the impact of a polymerase chain reaction (PCR) assay for the detection of pathogens in BAL fluid compared to standard culture methods in neutropenic children receiving broad spectrum antibiotics.

Methods: BAL fluids from nine neutropenic children (10,2 ± 5,9 years) under broad-spectrum antibiotics were investigated by a multiplex PCR system for DNA detection (LightCycler SeptiFast, Roche, Mannheim, Germany) and by conventional culture on solid media.

Results: SeptiFast detected more pathogens than conventional culture (7 vs. 1). In two patients clinical significant Aspergillus fumigatus was identified by SeptiFast, but not conventional culture.

Conclusion: Multiplex PCR for DNA detection can improve the detection of causative pathogens - including Aspergillus fumigatus - in neutropenic children under broad spectrum antibiotics.