Diagnostic and prognostic utility of neutrophil CD64 and monocyte HLA-DR in adult sepsis patients

To evaluate the diagnostic and prognostic accuracy of nCD64, mHLA-DR and sepsis Index (SI), ratio of nCD64 and mHLA-DR, in patients with sepsis. Prospective observational study was undertaken among 50 cases diagnosed with sepsis, 25 non-septic patients, and 25 healthy individuals as controls. Participants underwent flowcytometric estimation of nCD64 and mHLA-DR on the day of admission. The sepsis cohort had significantly higher nCD64 and lower mHLA-DR expression than both control groups (p-value: < 0.001). The sensitivity and specificity of nCD64 ABC (Antibodies Bound per Cell) for diagnosis of sepsis with a cut-off of 1152.16 was 94% and 74%, respectively. Similarly, for the Sepsis Index (cutoff-11.36), the sensitivity and specificity for the diagnosis of sepsis were 88% and 86%, respectively. The combination of sepsis index or CD64 (either positive) increased the sensitivity to 96%. Using the combination of all three markers (nCD64 ABC, mHLA-DR ABC, and SI), the sensitivity for diagnosis of sepsis approached 100%. Among flow cytometric variables, the sepsis index had a statistically significant association with hospital mortality on univariate analysis. However, overall, only the baseline SOFA score was independently associated with hospital mortality. nCD64 and sepsis index are good diagnostic markers in patients with sepsis.