Assessment of Platelet Indices as Biomarker for Neonatal Sepsis

Abstract

Introduction: There is a need to increase the diagnostic capability of the traditional septic screen by adding additional markers. Platelet indices are one such marker that is readily available in routine hemogram reports. Materials and Methods: In this cross-sectional study, all newborn babies were recruited who had signs or symptoms of sepsis or had high-risk factors. Those who had clinical sepsis with positive cultures and/or a positive sepsis screen were classified under group “cases” ( n = 174), whereas all neonates suspected to have sepsis but who had a negative blood culture and a negative sepsis screen were classified under group “control” ( n = 126). Blood culture, sepsis screen, and platelet indices [platelet count, mean platelet volume (MPV), and platelet distribution width (PDW)] were performed on all babies. Babies with congenital or acquired causes of platelet abnormalities (including medication use by mothers with antiplatelet activity) were excluded from this study. Results: In this study, a total of 300 newborn babies were recruited for final analyses. Overall culture positivity was 38%. The mean platelet count was lower in the cases group ( P < 0.001). MPV and PDW were higher in septic babies with statistically significant differences ( P < 0.0001 and P = 0.012, respectively). Thrombocytopenia was the most sensitive marker (85.60%). However, it had low specificity (28.2%). On combining all three platelet markers, specificity increased to 48.4% (with a sensitivity of 64.5%) in detecting babies with neonatal sepsis. The sensitivity of the septic screen alone was 58% (with a specificity of 32.62%). When combining the sepsis screen and platelet indices, the specificity for the diagnosis of neonatal sepsis increased to 62.6%. On receiver operator curve analyses, thrombocytopenia had the highest area under the curve (0.692), followed by MPV (0.644). Conclusion: Platelet indices may be used as sensitive markers in combination with traditional sepsis screening to make an early diagnosis of neonatal sepsis.