Analysis of the value of novel inflammatory indicators derived from complete blood count in predicting for pertussis in children.

Objective: Inflammatory indicators derived from complete blood count (CBC) have been shown to exhibit substantial clinical utility across a broad spectrum of infectious and inflammatory conditions, this study aimed to explore the potential value of CBC-derived inflammatory indicators in predicting for pertussis in children.

Methods: CBC parameters of all the participants included in this study were collected. The CBC-derived inflammatory indicators evaluated included the neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), [neutrophil + monocyte]-to-lymphocyte ratio (NMLR), systemic immune-inflammation index (SII), and systemic inflammatory response index (SIRI). The predictive value of CBC-derived inflammatory indicators was assessed using the receiver operating characteristic (ROC) curve analysis.

Results: A total of 892 pertussis children, 903 children with non-pertussis respiratory tract infection and 1,165 healthy children were included in this study. Compared to healthy children, the PLR in children with pertussis was significantly reduced (p < 0.001), whereas the levels of the other indicators were significantly increased. Simultaneously, the indicators in children with pertussis were significantly lower than those in children with non-pertussis infection. In the comparative analysis of inflammatory indicators across different age subgroups, all indicators in the pertussis group were significantly elevated in children < 2 years old, compared to those in both the non-pertussis group and the healthy group; conversely, in children > 2 years old, these indicators were significantly lower than those observed in the non-pertussis group. The ROC analysis results indicated that, aside from PLR, the CBC-derived inflammatory indicators demonstrated significant value in predicting for pertussis infection in children < 2 years old. Furthermore, the integration of multiple markers could enhance diagnostic performance.

Conclusion: CBC-derived inflammatory indicators, particularly NLR and NMLR, may serve as valuable tools for early predicting for pertussis in children under 2 years old in clinical practice.