Kinetics and correlation with body temperature of circulating interleukin-6, interleukin-8, tumor necrosis factor alpha and interleukin-1 beta in patients with fever and neutropenia.

Interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF) are important mediators of fever and inflammation, and are involved in the pathogenesis of sepsis. There is only limited data on serum concentrations of these proinflammatory cytokines in patients with fever and neutropenia, and their interrelationship and correlation with body temperature and clinical disease early in the febrile response during neutropenia have not been studied. Immunoreactive TNF, IL-1 beta, IL-6, and IL-8 in serum samples serially obtained from 14 adult patients with neutropenia and fever considered or documented to be due to infection were measured. IL-6 and Il-8 were consistently elevated in all patients, and correlated well with each other and with body temperature. Median peak concentration of IL-6 and IL-8 were 400 pg/ml (range: 100 to 41,000 pg/ml), and 1,025 pg/ml (range: 600 to 26,000 pg/ml), respectively, and levels of both cytokines rapidly declined in patients responding to antimicrobial therapy. Despite frequent sampling before and after the temperature peaks TNF and IL-1 beta, conversely, were less frequently detectable, with median peak values of < 10 pg/ml (range: < 10 to 150 pg/ml) for TNF, and 17 pg/ml (range: < 10 to 36 pg/ml) for IL-1 beta, respectively. The role of neutro- and monocytopenia with depletion of important cytokine producing and target cells in this particular cytokine response pattern needs to be further studied.