Risk factors for fatal infectious complications developing late after allogeneic stem cell transplantation.

Area of Science:

• Hematology
• Infectious Diseases
• Transplantation Medicine

Background:

• Infectious complications are a major cause of mortality following hematopoietic allogeneic stem cell transplantation (HSCT).
• Late infections, occurring more than six months post-transplant, are a significant but understudied cause of mortality.
• Understanding risk factors for late infections is crucial for improving patient outcomes.

Purpose of the Study:

• To analyze mortality due to infectious complications occurring more than six months after HSCT.
• To identify independent risk factors associated with death from late infections post-HSCT.
• To determine the types and timing of late infections contributing to mortality.

Main Methods:

• Retrospective analysis of a cohort of 688 patients undergoing HSCT.
• Identification of 44 patients who died from infectious complications more than six months post-transplant.
• Selection of 162 control patients matched by year of HSCT.

Main Results:

• Pneumonia was the most frequent cause of death (68%), followed by sepsis (16%).
• The majority of lethal infections (66%) occurred within 18 months after HSCT.
• Independent risk factors for mortality from late infections included acute GVHD (RR: 7.19), chronic GVHD (RR: 6.49), CMV infection (RR: 4.69), and use of a mismatched or unrelated donor (RR: 3.86).

Conclusions:

• Infections occurring later than six months post-HSCT significantly contribute to non-relapse mortality.
• Acute GVHD and CMV infection are major independent risk factors that markedly increase the risk of death from late infections.
• Targeted surveillance and management of infections, particularly in high-risk patients, are essential after HSCT.