Complement in acute leukaemia: its role in infection.

Area of Science:

• Immunology
• Hematology
• Oncology

Background:

• The complement system is vital for host defense.
• Acute myeloid leukemia (AML) treatment can impact immune function.

Purpose of the Study:

• To determine the frequency of complement system dysfunction in adult AML patients.
• To assess the prognostic significance of complement dysfunction during remission induction.

Main Methods:

• Complement studies were performed on 24 AML patients at presentation and during chemotherapy-induced nadir.
• Infection morbidity was assessed by febrile days and blood culture pathogen isolation.

Main Results:

• 32% of AML patients presented with abnormal complement function.
• Only 54% maintained normal complement activity during remission induction.
• Abnormal complement function correlated with increased infection morbidity (febrile days, positive blood cultures).

Conclusions:

• Complement system dysfunction is frequent in AML patients.
• Depressed complement activity significantly increases infection risk and morbidity during AML treatment.
• The complement system plays a critical role in host defense against infections in AML patients.