Evaluation of interleukin-8 level in the diagnosis of invasive pulmonary aspergillosis in patients with hematological malignancies

Objectives: The diagnosis of invasive pulmonary aspergillosis is based on the combined use of clinical, microbiological, and radiological methods. It is aimed to determine the level of IL-8 in the diagnosis of IPA. Materials and methods: This study was planned with 50 controls and 25 IPA patients with hematological malignancies. Demographic data, hematological diagnoses, chemotherapy, galactomannan level, fungal culture, and computed tomography findings of the patients were evaluated prospectively. Serum and BAL fluid samples were obtained from the patients. IL-8 levels were studied with the ELISA method. Results: The mean age of the patients in the case group was 60.84±15.38 years, and the mean age of the control group was 58.38±16.64 years. 2/25 (8%) of the patients were "proven," 13/25 (52%) "probable," 10/25 (40%) "possible" IA. Serum IL-8 levels were found to be significantly higher in the case group compared to the control group (p=0.007). However, no correlation was found between serum IL-8 levels and mortality (p=0.202). There was a negative correlation between serum IL-8 levels and neutrophil counts (r=-0.512;p<0.001), a positive correlation with the duration of neutropenia (r=0.459; p<0.001), and a weak positive correlation with galactomannan levels (r=0.294;p=0.038). A significant cut-off value for serum IL-8 parameter in detecting IPA disease was obtained ≥274 ng/L (AUC=0.693;p=0.007), sensitivity was 72%, specificity was 64%, PPV was 50% and NPV was 82%. In the subgroup analysis, there was no significant difference in serum IL-8 levels between the case group and the patients in the neutropenic control group (p=0.362), there was a significant difference found with the patients in the non-neutropenic control group (p<0.001). Conclusion: Serum IL-8 levels in neutropenic patients who develop IPA are not successful in the diagnosis of the disease and predicting mortality. There is still a need for new, easily applicable methods with high sensitivity and specificity in the diagnosis of IPA.