Invasive mould infections in the setting of hematopoietic cell transplantation: current trends and new challenges

Abstract

Invasive mould infections remain major causes of infection-related mortality following hematopoietic stem cell transplantation (HSCT). In this review, we summarize the recent advances in the diagnosis, prevention, and management of invasive mould infections in HSCT recipients. The evolving epidemiologic characteristics of post-HSCT invasive mould infections, specifically the rising incidence of Aspergillus and non-Aspergillus mould infections in the postengraftment period, necessitate the development of preventive strategies. The efficacy of prophylactic broad-spectrum triazoles against invasive mould infections in HSCT recipients has now been demonstrated in two large prospective studies. However, concerns over drug absorption, interactions, and costs may shift attention from universal prophylaxis to risk stratification and preemptive strategies. In this regard, recent studies have highlighted the potential of genetic polymorphism analysis to identify HSCT recipients at risk for invasive aspergillosis, and efforts are underway to improve the predictive values of antigen and nucleic acid detection assays. Emerging data on risk factors for invasive aspergillosis relapse after HSCT, antifungal drug monitoring, and the use of galactomannan testing to monitor treatment response may help inform therapeutic decisions for HSCT recipients. Evidence-driven management of invasive mould infections in HSCT recipients is becoming increasingly individualized, integrating host factors and pharmacologic and epidemiologic considerations. However, the optimal approach to invasive mould infection prevention in HSCT recipients remains to be resolved by prospective clinical studies.