Stroke mimics and chameleons.

The diagnosis of acute stroke remains a clinical diagnosis in the initial phases of patient evaluation. There is a differential diagnostic process to the abrupt onset of focal neurologic deficit that characterizes an acute stroke. "Is this a CNS event?" might be the initial question posed by the clinician. The stroke mimics of systemic problems such as hypoglycemia, hyperglycemia, and other encephalopathies are considered. Certainly consideration of hypoglycemia, which is common, easily detectable, and correctable, should occur in every stroke patient encounter. Any witnesses that suggest a convulsive episode should raise suspicion of the presence of an ictal or postictal phenomena. Next, if a CNS event is believed to exist, the different stroke subtypes are considered along with other CNS events that may simulate stroke. The standard acute neuroimaging with noncontrast CT scanning uncovers some mass lesions mimicking stroke and confirm a stroke subtype in other patients. Ischemic stroke, like other common diseases, does have uncommon manifestations. Acute stroke is considered in neurologic syndromes in which abrupt onset of symptoms figure prominently, particularly in patients with cerebrovascular risk factors.