BACKGROUND: The decreased estimated glomerular filtration rate (eGFR) levels at admission in patients with stroke have been associated with more severe clinical deficits and with worse outcomes; however, the relationship between eGFR levels and volumetric measurement of cerebral infarct size on neuroimaging has not been studied, to our knowledge. METHODS: Consecutive patients who presented within 48h of ischemic stroke and underwent brain diffusion-weighted imaging (DWI) over a 55-month period were studied. Patients with ischemic stroke of large artery atherosclerosis (LAA), small vessel occlusion (SVO), or cardioembolism (CE) etiologies were included. Those who were treated with thrombolysis and disabled before index stroke were excluded. Infarction volumes were log transformed to approximate normality. Chronic kidney disease (CKD) was defined as an eGFR < 60 mL/min per 1.73 m2. Subjects were categorized into two groups: CKD or no CKD. The relationship between CKD and DWI infarct volumes was examined using an analysis of covariance. RESULTS: Of the included 405 patients (mean age, 68 years; female, 60.2%; LAA, 60.0%; SVO, 16.5%; CE, 23.5%), 108 patients had CKD. Infarct volumes (mL, median [interquartile range]) were not significantly different between stroke patients with CKD and those without CKD in any stroke subtype (LAA, 0.77 [0.01-2.97] vs. 0.96 [0.01-5.22]; SVO, 0.18 [0.02-0.21] vs. 0.27 [0.01-0.52]; CE, 8.91 [0.04-28.54] vs. 5.22 [0.05-42.39]). Adjustment for possible confounders did not change the associations. CONCLUSIONS: Renal impairment is not associated with cerebral infarct volume among acute ischemic stroke patients.