It is increasingly recognized that modulation of brain inflammation may uncover new potential therapeutic strategies for stroke. Recent studies have shifted focus from immunological implications in ischemic stroke to a more devastating form; the hemorrhagic stroke.The aim of this study was to investigate the neuroinflammatory response in cerebrospinal fluid in patients with primary intracerebral hemorrhage (ICH) associated with intraventricular hemorrhage (IVH) in the presence of low-dose recombinant tissue plasminogen activator (rt-PA).This retrospective study included 88 adults with primary ICH associated with IVH. Patients were divided into 2 groups: rt-PA group and non-rt-PA group, which received normal standard of care for this diagnosis. The rt-PA group was treated via catheter-based clot lysis using low-dose rt-PA injected through the external ventricular drain (EVD) system, and the non-rt-PA group was treated with saline applied to EVD system in equivalent volume. Cerebrospinal fluid samples from rt-PA were obtained from the EVD system at 4 time points: once before the drug administration, and then on day 1, 3, and 7. No attempt at randomization was made. The decision to inject rt-PA was based on the preference of the primary attending neurologist and the ability to obtain consent. Temporal interleukin-1 beta and transforming growth factor beta concentration changes were analyzed and compared between the 2 groups.The concentration of interleukin-1 beta was significantly lower in the rt-PA group than in the non-rt-PA group on day 7. In addition, the concentration of transforming growth factor beta was significantly higher in the rt-PA group than in the non-rt-PA group on day 1. There was a significant difference in interleukin-1 beta concentration between days 0 and 1 in comparison to day 3 in the rt-PA group, and between day 0 in comparison to day 3 and 7 in the non-rt-PA group. We also observed a significant difference in transforming growth factor beta concentration between days 0 and 1 and between days 3 and 7.The different pattern of pro- and anti-inflammatory cytokines in patients with ICH associated with IVH suggest distinct characteristics of secondary brain injury depending on the treatment modality.