Polymerase-chain-reaction-based diagnosis of invasive fungal pulmonary infections in immunocompromised children

Objective Fungal pneumonia is a serious complication in immunocompromised children. It is difficult to diagnose because of the low sensitivity of clinical and standard laboratory tests. The aim of this study was to investigate the diagnostic impact of polymerase chain reaction (PCR) assays for fungal pathogens in bronchoalveolar lavage (BAL) fluid. Study Design BAL samples obtained from hospitalized immunocompromised patients with clinical pneumonia between January 2007 and June 2009 were processed for microscopy and cultures in addition to PCR-based fungal assays. The results were compared between the standard and PCR methods. Results Seventy-seven children with 100 episodes of pneumonia were included in the study. Fungal pathogens were detected by standard microbiological investigations in 10 episodes (10%) and by PCR-based assays alone in 20 episodes (20%). There was no significant difference in clinical improvement or mortality rate between patients diagnosed by the different methods. In 61 episodes, no fungal pathogen was identified by either method. Prolonged antifungal therapy was avoided in 43 episodes. Conclusion PCR-based assay for the diagnosis of fungal pulmonary infections may be a useful adjunct to clinical and standard microbiological techniques. The use of PCR may decrease the time to diagnosis, increase the rate of detection of fungal pathogens, and spare patients unnecessary antifungal treatment. Pediatr Pulmonol. 2012. 47:994-1000.