Abstract WMP107: Cerebrospinal Fluid Leukocyte Subtypes After Intraventricular Hemorrhage: An Analysis of the CLEAR-III Trial

Abstract

Background: Intracerebral hemorrhage (ICH) results in significant mortality and morbidity and initiates a cascade of inflammatory cell activation. Leukocyte subtypes have different effects, with monocytes contributing to increased hematoma expansion and mortality and neutrophils decreasing hematoma expansion. However, the response of cerebrospinal fluid (CSF) leukocytes to ICH with IVH has not been investigated. Methods: We retrospectively analyzed CSF and serum leukocyte counts from patients enrolled in CLEAR-III. After correction for CSF red blood cell (RBC) counts, data were plotted chronologically. Linear mixed-effects models were used to assess the differences in leukocyte subtypes after intraventricular saline or alteplase. Generalized linear models are being created to assess the relationship between CSF leukocyte subtypes and IVH volumes and 30, 60, 90, and 180-day outcomes. Results: Data were available for 237 and 228 patients in the saline and alteplase groups, respectively. Serum total white blood cell (WBC) and neutrophil counts increased after ICH, peaking at two days. Significant increases occurred in serum monocyte and lymphocyte counts, peaking at 6 and 10 days, respectively. Intraventricular alteplase had no effect on serum leukocyte counts. Peak CSF leukocyte counts occurred on day 1 after IVH (pretreatment) in the saline group. However, intraventricular alteplase resulted in a significant increase in WBC ( P =0.0001), neutrophil ( P =0.0003), monocyte ( P =0.0064), and lymphocyte counts ( P= 0.0339), peaking two days after starting treatment. No significant associations between peak serum or CSF cell counts and 30, 180, and 365 day modified Rankin Scale were found. Conclusions: ICH drives an increase in serum leukocyte counts. Intraventricular alteplase results in an increase in all CSF leukocyte subtypes. Further work will be presented on the complex interactions between leukocyte counts, ICH severity, and outcomes.