The implications of platelet count changes during hospitalization in the disease management of pediatric patients with bronchiolitis

Background: The clinical implications of platelet count changes in patients with bronchiolitis throughout hospitalization have not been extensively investigated. We aimed to investigate the significance of platelet count on admission and platelet count changes during hospitalization in pediatric patients with bronchiolitis. Methods: Clinical data from 559 consecutive patients hospitalized for bronchiolitis were collected and compared after grouping according to the platelet count on admission and the delta platelet count during hospitalization (the platelet count on discharge minus the platelet count on admission; Group A, delta platelet count ≤ -50 × 109/L; Group B, -50 × 109/L 50 × 109/L). Results: Thrombocytosis was found in 122 (21.8%) patients, while 437 (78.2%) patients had a normal platelet count on admission. There was no difference in disease severity between these two groups. Groups A, B, and C comprised 79 (14.1%), 179 (32.0%), and 301 (53.9%) patients, respectively. The patients from Group A had a higher platelet count on admission, a lower platelet count on discharge, and a longer hospitalization duration. These patients had a lower concentration of C-reactive protein, longer periods of oxygen therapy and stay in the pediatric intensive care unit (PICU), and a greater frequency of mechanical ventilation than the patients from Group B or Group C. Notably, among all the patients, the delta platelet count [63 (-3–142) × 109/L] negatively correlated with the numbers of days of oxygen therapy [4.0 (3.0–6.0), day] (r = -0.186, P = 0.027) and stay in the PICU [5.0 (3.0–6.0), day] (r = -0.391, P = 0.001). Conclusions: Repeated assessment of platelet count during hospitalization in pediatric patients with bronchiolitis may provide useful information for disease management.