Changing Epidemiology of Invasive Fungal Disease in Allogeneic Hematopoietic Stem Cell Transplantation

Abstract

Invasive fungal disease (IFD) is a common cause of morbidity and mortality in patients with hematologic malignancies, especially among those undergoing allogeneic hematopoietic stem cell transplantation (HSCT). The epidemiology of IFD in HSCT patients has been evolving over the last decades, mainly in relation to changes in HSCT therapies such as antifungal prophylaxis. A progressive decrease in Candida albicans infection has been documented, alongside a progressive increase in infections caused by non-albicans Candida species, filamentous fungi, and/or multidrug-resistant fungi. Currently, the most frequent IFD is invasive aspergillosis. In some parts of the world, especially in north Central Europe, a high percentage of Aspergillus fumigatus isolates are azole-resistant. New diagnostic techniques have documented the existence of cryptic Aspergillus species with specific characteristics. An increase in mucormycosis and fusariosis diagnoses, as well as diagnoses of other rare fungi, have also been described. IFD epidemiology is likely to continue changing further due to both an increased use of mold-active antifungals and a lengthened survival of patients with HSCT that may result in hosts with weaker immune systems. Improvements in microbiology laboratories and the widespread use of molecular diagnostic tools will facilitate more precise descriptions of current IFD epidemiology. Additionally, rising resistance to antifungal drugs poses a major threat. In this scenario, knowledge of current epidemiology and accurate IFD diagnoses are mandatory in order to establish correct prophylaxis guidelines and appropriate early treatments.

Candida albicans biofilm formation and growth optimization for functional studies using response surface methodology

“…Candida albicans has been identified as one of the most common nosocomial pathogens in recent years due to its ability to form biofilm and resistance to antimycotic agents (Bakhtiari et al, 2020; Mishra et al, 2014). They cause the most common invasive fungal infection and are the most frequent infection in hospitals worldwide (Brown et al, 2012; Osman et al, 2020; Puerta‐Alcalde & Garcia‐Vidal, 2021). Nearly, 65% of all human infections are due to microbial biofilm formation (Atriwal et al, 2021).…”

A Whole Genome Sequencing-Based Approach to Track down Genomic Variants in Itraconazole-Resistant Species of Aspergillus from Iran

“…Among susceptible patients with impaired immune functions for a variety of reasons, such as solid organ transplant recipients and hematopoietic stem cell transplant recipients, A. fumigatus , A. niger , A. terreus , and A. flavus are the most common isolated species of IA, but the role of cryptic species should not be overlooked [ 29 ]. Species that appear to be cryptic might be neglected because of misidentification and therefore, it would be difficult to assess their epidemiological distribution pattern and antifungal susceptibility profile [ 5 ].…”

Non-Aspergillusmould lung infections

“…This holds especially true in those patients who have received multiple prior lines of treatment [17,18]. IFD epidemiology in patients with haematological malignancies has been highly influenced by the widespread introduction of antifungal prophylaxis in high-risk populations [2]. At the beginning of the current century, fluconazole prophylaxis became the standard of care in neutropenic patients with haematological malignancies, since some trials had demonstrated a reduction in fungal infection and mortality [19][20][21].…”