The diagnostic value of serum level of soluble hemoglobin scavenger receptor CD163 for sepsis in the ICU

Background Sepsis is the most important cause of morbidity and mortality in the ICU; however, sepsis lacks specific clinical manifestations. Current common clinical and laboratory indicators of infection include pyrexia, white blood cell counts (WBC), C-reactive protein (CRP), and procalcitonin (PCT). Aim We investigated serum-soluble CD163 (sCD163) levels in Egyptian patients in the ICU and its use in the diagnosis and severity assessment of sepsis, and compared sCD163 with other infection-related variables such as leukocyte counts, CRP, and PCT. Patients and methods A total of 20 patients with systemic inflammatory response syndrome (SIRS) were enrolled and 20 patients with sepsis were admitted to the ICU during the 6-month period. Serum levels of soluble hemoglobin scavenger receptor CD163 (sCD163), CRP, WBC count, and PCT were determined. Sequential Organ Failure Assessment scores for severe sepsis were also evaluated. Results On the day of ICU admission, patients in the sepsis group exhibited higher levels of serum sCD163 (2.41 ± 0.69 ng/ml) compared with those in the SIRS group (0.83 ± 0.19 ng/ml, P r = 0.356, P = 0.006), erythrocyte sedimentation rate ( r = 0.471, P = 0.005), and CRP ( r = 0.526, P = 0.001). The receiver operating characteristic curve for CRP for the diagnosis of infection showed that the reading of greater than 3.0 serves as a cutoff point for diagnosis, with a sensitivity of 86.7% and specificity of 90.2% in the studied groups, whereas for PCT the reading of 3.36 serves as a cutoff point for diagnosis, with a sensitivity of 91.6% and a specificity of 88.7% in all studied groups. sCD163 showed a cutoff point greater than 5.36, with a sensitivity of 93.5% and a specificity of 90.2%; this indicated that sCD163 was better than PCT and CRP for the diagnosis of sepsis. Conclusion sCD163 appeared to be a new diagnostic parameter for differentiating between patients suffering from SIRS and those with sepsis.