Eligibility CriteriaInclusion criteria:
- Age older than 18 years old.
- Acute ischemic stroke treated with rtPA within the first 4.5 hours of clinical onset. Baseline National Institute of Health Stroke Scale (NIHSS) >6 and <25, and modified Rankin Scale (mRS) of 2 prior to the stroke.
- Cranial CT disclosing the absence of blood in the CNS.
- Informed consent.
- Presence of any of the valid exclusion criteria for the administration of rtPA in the current clinical practise.
- History of gout with or without history of gouty nephropathy, or uric lithiasis. Asymptomatic hiperuricemia under chronic treatment with allopurinol, or chronic treatment with lithium.
- Chronic renal insufficiency (baseline creatinine > 1,5mg/dl).