A59-09 Describing Polymorphonuclear Leukocytes Profiles in Tracheal Aspirates of Children With Tracheostomies

Rationale Substantial variation exists in the diagnosis of bacterial tracheitis among children with tracheostomiescs. Abundant polymorphonuclear lymphocytes (PMNs) on tracheal aspirates are commonly used by clinicians in the diagnosis of tracheitis. However, limited data exists describing the PMN profiles among healthy children with tracheostomies. The utility of abundant PMNs on tracheal aspirates in supporting a diagnosis of tracheitis is unknown. This study sought to characterize the PMN profiles among healthy children with tracheostomies. We hypothesized that at least one-third of well children with tracheostomies would have abundant PMNs present on their tracheal aspirates. Methods We performed a retrospective cohort study evaluating the demographic and clinical characteristics of children with tracheostomies seen at the Seattle Children’s Hospital ventilator clinic between January 1, 2024, and September 30, 2025, who had a tracheal aspirates acquired at clinic. Tracheal aspirate gram stain and culture results, chronic medical conditions, medication history, and demographic data were reviewed. Multivariable logistic regression was performed incorporating factors a priori hypothesized to be associated with abundant PMNs on tracheal aspirate. Results Altogether, 36 children were included for analysis (Table 1). Notably, twenty children (56%) had a tracheal aspirate collected as part of routine care (i.e., when well), and 45% of these collected samples had abundant PMNs. Sixteen children (44%) had a tracheal aspirate collected because they were sick, and 62.5% of these collected samples had abundant PMNs. Compared to sick children, there was not a reduced odds of having abundant PMNs among tracheal aspirates from well children (OR 0.40, 95% CI: 0.093, 1.75, p = 0.224). None of the other factors included in the multivariable regression model were found to be associated with abundant PMNs on tracheal aspirate. Conclusions In our small single-center study, almost half of well children had abundant PMNs on their tracheal aspirates, and none of the measured factors were associated with an increased odds of having abundant PMNs on tracheal aspirate. These results suggest that the presence of abundant PMNs on tracheal aspirate alone might not be a reliable marker for tracheitis diagnosis.