Admission Leukocytosis Is Not Associated with Early Response to Tissue Plasminogen Activator in Patients with Acute Ischemic Stroke (P02.198)

Abstract

Objective: We examined the relationships between admission leukocytosis and clinical response to intravenous tissue plasminogen activator (rt-PA) and early clinical outcomes in patients with acute ischemic stroke (AIS) receiving rt-PA. Background In patients with acute coronary events treated with IV rt-PA, the presence of leukocytosis is associated with impaired microvascular perfusion and increased re-occlusion rates. Within 24hr of an ischemic event, neutrophils and other acute-phase mediators invade the ischemic tissue releasing pro-inflammatory cytokines promoting endothelial damage. The degree of acute-phase response is related to infarct size and functional outcome. Design/Methods: We undertook a single-center retrospective analysis of patients treated with IV rt-PA for AIS between July 2008 and June 2010. Patients were excluded for in-hospital strokes, infections within 72hr of admission, and for corticosteroids taken in the month before admission or during hospitalization. Leukocyte counts were considered elevated if it exceeded our laboratory reference range for normal ( Results: Eighty-five patients met inclusion criteria; 20% had leukocytosis. Age, race, glucose, and NIHSS were similar, but patients with leukocytosis were more likely to be female (p=0.049). No difference in ΔNIHSS from admission to 24hr post-tPA was detected in patients with leukocytosis (or elevated neutrophils or lymphocytes) compared to those with normal WBC counts. Patients with leukocytosis had similar frequencies of sICH, neurological deterioration, and length of stay and similar median mRS scores. The ΔNIHSS from admission to discharge was significantly greater (p=0.0044) in patients with leukocytosis, but other outcomes were similar (sICH, neurological deterioration, length of stay, and mRS). Conclusions: At our center, patients with AIS and leukocytosis at the time of IV rt-PA had similar improvement in NIHSS when compared to those with normal WBC counts, arguing against a deleterious interaction. The improvement in NIHSS score by discharge and higher frequency of favorable discharge disposition requires validation and further exploration. Disclosure: Dr. Gillette has received research support from the Infectious Disease Society of America. Dr. Siegler has nothing to disclose. Dr. Kumar has nothing to disclose. Dr. Boehme has nothing to disclose. Dr. Martin-Schild has nothing to disclose. Dr. Albright has nothing to disclose.