What is the initial workup for stroke in a young patient?

Workup for Stroke in Young Patients

Young stroke patients require comprehensive brain and vascular imaging with MRI/MRA as the preferred modality, cardiac evaluation including echocardiography (both transthoracic and transesophageal), extensive laboratory testing for hypercoagulable states and systemic conditions, and specialized investigations for arteriopathies, dissection, and monogenic causes—all coordinated through referral to a specialized stroke center. 1

Initial Imaging Evaluation

Brain Imaging Priority

• MRI with diffusion-weighted imaging (DWI) is the imaging procedure of choice for stroke detection in young patients, demonstrating 77% sensitivity within the first 3 hours compared to only 16% for CT 1
• MRI remains superior to CT for detecting infarction up to 12 hours after symptom onset and can detect significant intracranial hemorrhage as readily as CT 1
• Susceptibility-weighted imaging (SWI) should be included to improve detection of blood products, depict cerebral venous structures, and identify intravascular thrombus (appearing as "blooming" artifact within vessels) 1
• CT may be used initially if MRI is unavailable, but follow-up MRI is essential as CT is non-diagnostic in approximately 34% of pediatric stroke cases 2

Vascular Imaging Requirements

• MRA or CTA from aortic arch to vertex should be completed within 24 hours to evaluate both extracranial and intracranial circulation 1
• MRA should include cervical vessels in all cases of unexplained stroke, as cerebral arterial abnormalities are found in 25% of young stroke patients 1
• Very high-resolution MRI with vessel wall imaging may show thickening or enhancement in arteriopathies, which are the most common cause (53%) of pediatric stroke 1
• Cerebral angiography remains the most definitive means of imaging vascular abnormalities when non-invasive studies are inconclusive 1

Cardiac Evaluation

Echocardiography

• Both transthoracic and transesophageal echocardiography should be performed in young stroke patients, as cardiac disorders account for 31% of pediatric strokes 1
• Transesophageal echocardiography is particularly important for detecting patent foramen ovale, atrial septal abnormalities, and potential sources of cardioembolism not visible on transthoracic studies 1
• Initial C-reactive protein ≥10 mg/L dramatically increases likelihood of infectious endocarditis (OR 22), which is confirmed in 1.7% of stroke presentations 1

Cardiac Monitoring

• 12-lead ECG should be completed immediately upon presentation 1, 3
• Extended cardiac monitoring (telemetry) should be performed to detect paroxysmal atrial fibrillation and other arrhythmias 1

Laboratory Investigations

Initial Bloodwork

• Complete blood count, electrolytes, coagulation studies (aPTT, INR), renal function (creatinine, eGFR), random glucose, and troponin should be obtained routinely 1, 3

Specialized Testing for Young Patients

• Hypercoagulable state testing should be performed in patients <50 years of age, as the yield is significantly higher in younger populations 1
• Toxicology screening for cocaine and other drugs of abuse should be done at presentation, as cocaine use within 24 hours increases stroke risk >6-fold in young adults 1
• When diagnostic algorithms are used, monogenic causes of stroke are detected in 7% of cases, making genetic testing an important consideration 1
• Testing for systemic conditions including infection (present in 24% of pediatric strokes), acute or chronic systemic conditions (41%), and other causes should be tailored based on clinical suspicion 1

Specialized Investigations

Arteriopathy Evaluation

• Arteriopathies are the leading cause of stroke in young patients (53%), requiring detailed vascular assessment 1
• Evaluation for arterial dissection should be pursued when suspected, as this may require referral to a level three facility for specialized management 1
• Basilar artery occlusion and vertebral artery dissection should be specifically evaluated, as basilar circulation strokes account for 4.6% of pediatric cases 1

Additional Considerations

• Acute or chronic head and neck disorders account for 23% of pediatric strokes and should be investigated 1
• 52% of children have multiple risk factors, necessitating comprehensive evaluation across all categories 1

Referral Criteria

Indications for Specialized Stroke Center

• Stroke in young patients for which no cause can be found after initial workup requires referral to a level three comprehensive stroke unit 1
• Suspected cardioembolic stroke not associated with atrial fibrillation and not previously investigated requires specialized evaluation 1
• Patients requiring investigations unavailable at the initial facility (e.g., suspected arterial dissection, need for catheter laboratory procedures) should be transferred 1

Critical Pitfalls to Avoid

• Do not rely on initial CT scanning alone in young stroke patients—CT is non-diagnostic in 34% of cases, and when initial imaging is non-diagnostic, median time to diagnosis extends to 44 hours 2
• Do not delay MRI for young patients presenting outside normal working hours, as this results in significant diagnostic delays (13 vs 3 hours) 2
• Do not overlook stroke mimics such as postictal paralysis or complicated migraine, which SWI can help differentiate by demonstrating characteristic susceptibility changes 1
• Do not assume a single etiology—maintain broad differential as multiple risk factors coexist in over half of young stroke patients 1