Cytokine response to infection in patients with acute myelogenous leukaemia following intensive chemotherapy

Abstract
Septic shock is the major cause of treatment-related death in patients with acute myelogenous leukaemia (AML) undergoing intensive chemotherapy. Interleukins (IL)-1 beta, -6, -8, and tumour necrosis factor alpha (TNF-alpha) have been implicated as mediators of septic shock, with circulating leucocytes being considered a major source for their release. However, plasma cytokine levels of leucocytopenic patients with evolving sepsis have not been studied. We have prospectively measured plasma cytokines during chemotherapy-induced leucocytopenia (< 1 x 10(9)/l) in 50 patients with AML. Cytokine levels in patients with severe sepsis (n = 5) or septic shock (n = 8) were compared to those measured in 13 matched patients with uncomplicated febrile infections. In evolving septic shock, IL-6, IL-8 and TNF-alpha peaked within 48 h of fever onset at levels reported for non-leucocytopenic patients and distinctively higher than during uncomplicated febrile episodes (P < 0.05). Peak concentrations measured within 48 h after onset of fever were related to fatal outcome. IL-1 beta was detected in less than 5% of all samples. Cytokine concentrations were unrelated to leucocyte counts and markers of neutrophil or monocyte activation (elastase and neopterin levels, respectively). We conclude that cytokine release associated with evolving septic shock in patients with AML does not depend on circulating leucocytes.