Infectious Diseases in Immunocompromised Hosts

Infectious diseases are the leading cause of morbidity and mortality among immunocompromised hosts. Bacteremia occurs in up to 25% of all patients with neutropenia and fever. Infection is a leading cause of non-relapse mortality among hematopoietic cell transplantation (HCT) recipients. The incidence of bacteremia and double-stranded DNA viral reactivation is higher than 40% and 90%, respectively, within the first 100 days post-transplant. The cumulative incidence rate of proven/ probable invasive fungal infections during the first year after allogeneic HCT with non-myeloablative conditioning is 19%. Infection is also a common complication of chimeric antigen receptor-modified T (CAR-T)-cell immunotherapy with a 28-day cumulative incidence of 23% after CAR-T-cell infusion. Establishing a microbiological diagnosis of infectious diseases in this vulnerable population is often challenging for a number of reasons. Thus, there is an unmet need for novel, rapid, cost-effective, non-invasive diagnostic methods in the field.

The emergence and spread of MDR pathogens have become a major leading cause of death worldwide and a major problem in immunocompromised hosts. ESKAPE pathogens reflect the strongest challenge today. The increasing prevalence of MDR bacteria is associated with increased 3rd generation cephalosporins-resistant K. pneumoniae and cephalosporins-resistant E. coli which lead to more frequent use of carbapenems and to the emergence of XDR and/or PDR Enterobacteriaceae. The unsafety against a probable infection leads to massive consumption of antibiotics while de-escalation and shortened treatment duration are considered insufficiently in those with documented infection, promoting substantial ecological side effects and dissemination of MDR pathogens. The optimization of antibiotic therapy in immunocompromised hosts is extremely important supporting the need for better identification of high-risk patients for MDR infections, more accurate diagnostic tools, individualization of single-drug or combination empirical regimen and early and adequate dosing to ensure the attainment of pharmacokinetics/pharmacodynamics targets. The evidence-based administration and antibiotic stewardship programs (ASP), the performance of infection control programs, the PK/PD-based dosing, the development of new antibiotics and the application of vaccination programs reflect important strategies to fight the difficult infections in immunocompromised hosts.

We welcome submissions of studies (Frontiers in Microbiology - Article Types) focusing on, but not limited to, the following themes:

• New techniques for rapid noninvasive diagnosis of infectious diseases in immunocompromised hosts.
• Novel biomarkers application in immunocompromised hosts with infectious diseases.
• Immunocompromised hosts, infectious diseases and intestinal microecology.
• Immune function monitoring and regulation in severe infections or sepsis.
• Co-infection between bacteria and fungi associated with immunocompromised hosts.
• Active screening and management of multi-drug resistant bacteria in immunocompromised hosts.
• Infections associated with biological agents in in-patients with underlying rheumatologic diseases.
• Mixed biofilm and immunoregulation.
• Antibiotic stewardship to avoid antibiotic misuse and contain the emergence of antimicrobial resistance in immunocompromised hosts.
• Prediction model for multiply drug-resistant strains and mixed infection in immunocompromised hosts.
• Vaccine development against COVID-19/opportunistic pathogens in immunocompromised hosts.