Ischemic Stroke Differential Diagnoses

Updated: May 27, 2020
  • Author: Edward C Jauch, MD, MS, FAHA, FACEP; Chief Editor: Helmi L Lutsep, MD  more...
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DDx

Diagnostic Considerations

Stroke mimics commonly confound the clinical diagnosis of stroke. One study reported that 19% of patients diagnosed with acute ischemic stroke by neurologists before cranial CT scanning actually had non-cerebrovascular causes for their symptoms.

The most frequent stroke mimics include the following:

  • Seizure (17%)

  • Systemic infection (17%)

  • Brain tumor (15%)

  • Toxic-metabolic disorders, such as hyponatremia and hypoglycemia (13%)

  • Positional vertigo (6%)

  • Conversion disorder

In the prehospital and Emergency Department (ED) settings, hypoglycemia is a common stroke mimic and is particularly important to consider, since it can be readily detected and corrected. [59, 60] For more information, see Hyperglycemia and Hypoglycemia in Stroke.

Ischemic versus hemorrhagic stroke

Although the definitive distinction of ischemic stroke from hemorrhagic stroke requires neuroimaging, a meta-analysis found that the following clinical findings increase the probability of hemorrhagic stroke [61] :

  • Coma (likelihood ratio [LR] 6.2)

  • Neck stiffness (LR 5.0)

  • Seizures accompanying the neurologic deficit (LR 4.7)

  • Diastolic blood pressure >110 mm Hg (LR 4.3)

  • Vomiting (LR 3.0)

  • Headache (LR 2.9)

Findings that decrease the probability of hemorrhage include cervical bruit (LR 0.12) and prior transient ischemic attack (LR 0.34).

Transient ischemic attack

Transient ischemic attack (TIA) is an acute episode of temporary neurologic dysfunction that results from focal cerebral, spinal cord, or retinal ischemia and is not associated with acute tissue infarction. Roughly 80% of TIAs resolve within 60 minutes. [62] TIA can result from the same mechanisms as ischemic stroke. Data suggest that roughly 10% of patients with TIA will suffer a stroke within 90 days and of those, half suffer a stroke within 2 days. [63, 64]

The classic definition of TIA included symptoms lasting as long as 24 hours. With advances in neuroimaging, however, it now appears that many such cases presumed to be TIA actualy are minor strokes with areas of infarction found on imaging but with resolved symptoms, rather than true TIAs. Thus, the current definition of TIA is based on tissue pathophysiology rather than symptom duration. [62]

Cerebral venous thrombosis

Diagnosis and management of a rare form of stroke, cerebral venous thrombosis (CVT), was the subject of a 2011 American Heart Association/American Stroke Association (AHA/ASA) statement for healthcare professionals. According to the statement, diagnosing CVT requires a high degree of clinical suspicion. Most people diagnosed with CVT present with headache, often of increasing severity and usually accompanied by focal neurologic signs. [50]

Differentials

Bell Palsy

Brain Neoplasms

Conversion Disorder in Emergency Medicine

Hemorrhagic Stroke

Hypoglycemia

Migraine Headache

Seizure Assessment in the Emergency Department

Emergent Management of Subarachnoid Hemorrhage

Syncope

Transient Global Amnesia