Interleukin-8 serum levels at fever onset in patients with neutropenia predict early medical complications.

BACKGROUND

Previous studies have shown that interleukin-8 serum levels in febrile neutropenic patients are significantly higher in patients with gram-negative bacteremia than in patients with other causes of fever and may indicate unfavorable outcomes. We assessed the value of interleukin-8 serum levels at fever onset to predict clinical complications in order to confirm these earlier findings.

PATIENTS AND METHODS

In a prospective observational study of adult patients receiving cancer chemotherapy, serum samples obtained at the onset of 147 febrile neutropenic episodes were measured by an immunoluminescence assay.

RESULTS

Complicated courses of fever including severe sepsis or septic shock, respiratory insufficiency or death were observed in 13 episodes (9%); in six episodes complications had developed within 1 week after fever onset and five of them were associated with bloodstream infections. At an interleukin-8 cutoff level of 1,000 pg/ml, these early complications were predicted with a sensitivity of 83%, a specificity of 97%, a positive predictive value of 50%, and a negative predictive value of 99%, respectively.

CONCLUSION

Interleukin-8 levels at fever onset may be used for the prediction of early medical complications associated with bacteremia and can help identify patients who might benefit from intensive care admission.