What Causes Pediatric Stroke?

Patient Presentation
A 3-year-old male came to clinic for a pre-operative evaluation. Six weeks prior, he acutely couldn’t walk and was taken to an emergency department. There he became unable to move his left arm and had difficulty talking. He was transferred to the regional children’s hospital and was diagnosed with moyamoya disease. He will have surgery in one week. His workup for other underlying causes of stroke was negative. During the past 6 weeks he has been improving with physical therapy, occupational therapy and speech therapy in the home. The past medical history showed a healthy boy with no known underlying medical problems. The family history was positive for coronary artery disease, hypertension and stroke in older family members, but no hematologic, cardiac, vascular or genetic problems. There were no sudden or unexplained deaths, or fetal loss. The review of systems was negative.

The pertinent physical exam shows a smiley boy who cognitively appears appropriate. His vital signs were normal with growth parameters in the 25-75%. His neurological evaluation shows him to be alert and oriented x 4. He has very mild dysarthria. Left arm and leg show strength to be +4/+5 with a mild limp that becomes more pronounced with running. He will use both hands but prefers the right. Coordination is fairly good when appropriate body support is provided. The rest of the examination is normal. The diagnosis of moyamoya disease was made. He was to return for ongoing care coordination and support service evaluation after the surgery.

Discussion
Stroke is “…the sudden occlusion or rupture of cerebral arteries or veins resulting in focal cerebral damage and clinical neurological deficits that persist for longer than 24 hours. Stroke can be ischemic, hemorrhagic or both.” Pediatric stroke, especially in a seemingly well child, is uncommon, but not as uncommon as often presumed. Outside the perinatal time period, the rate is 2-13 events /100,000 children/year or about the same rate as pediatric brain tumors. It unfortunately is also common cause of morbidity (75% of survivors have neurological deficits) and death (one of the 10 most common causes). Pediatric stroke presentations includes dystonia, emesis, fever, headache, hemiparesis, irritability, lethargy, and seizures. Adult stroke is often due to arteriosclerosis, but pediatric stroke is commonly due to congenital or genetic problems or other underlying medical problems. Pediatric stroke is also often due to several processes in concert (e.g. patient with Tetrology of Fallot, status post cardiac surgery who becomes dehydrated). Pediatric stroke may occur at any age including in utero and perinatally.

Moyamoya disease or syndrome is an arteriopathy of unknown origin that causes progressive stenosis of the apices of the intracranial internal carotid arteries. It is associated with cerebral ischemia and stroke. Moyamoya disease is the term used for arteriopathy alone, and moyamoya syndrome is the term used when there are associated conditions such as hyperthryoidism, Neurofibromatosis type 1, Down syndrome, and others. Moyamoya is a Japanese term meaning “puff of smoke” because the compensatory collateral cerebral vasculature on angiography is so tortuous and thin that it looks like a puff of smoke. Surgical treatment, while taking many forms, often tries to resect the abnormal vessels and reanastamose with the collaterals.

Moyamoya if left untreated progresses with poor outcomes, so surgery improves outcomes. In 3 large studies, perioperative surgical complications included stroke (0-4% of procedures) with one study reporting only 2 strokes in their patients who were followed for 5 years. The best indicator of long term outcome is the neurologic status at the time of surgery.

Acute hemiplegia such as the patient above, has other causes besides stroke including alternating hemiplegia, transient postictal hemiparesis, and complicated migraine.

Learning Point
The differential diagnosis of pediatric stroke includes:

• Cardiac (25-50%)
  • Acquired heart disease
  • Congenital heart disease
  • Cardiac surgery
• Drugs
  • Cocaine
  • Methamphetamine
  • Phencyclidine
• Hematologic
  • Abnormal coagulation
    • Disseminated intravascular coagulation
    • Hemophilia
    • Hypercoagulable state (35%)
    • Polycythemia
    • Thrombocytopenia
  • Sickle cell anemia
• Genetic
  • Aicardi-Goutieres syndrome
  • Alagile syndrome
  • Arterial tortuosity syndrome
  • CADASIL syndrome
  • CARASIL syndrome
  • Fabry’s disease
  • Homocystinuria
  • Pseudoxanthoma elasticum
  • Neurofibromatosis type 1
  • Menke’s disease
  • Williams-Beuren syndrome
• Neurological
  • Perinatal asphyxia and sequelae
• Trauma
  • Air or fat emolism
  • Arterial dissection (10-25%)
  • Head trauma
• Vascular
  • Fibromuscular dysplasia
  • Migraine
  • Moyamoya disease (25%)
• Vasculitis
  • Inflammatory bowel disease
  • Kawasaki disease
  • Meningitis
  • Systemic lupus erythematosus
  • Takayasu arteris
• Miscellaneous
  • Dehydration – severe
  • Hypotension

Questions for Further Discussion
1. What types of congenital heart diseases have increased risk for stroke?
2. What is the proposed mechanism for cocaine to cause stroke?
3. What medical evaluation should be completed for a patient with stroke?

Related Cases

Disease: Moyamoya Disease | Stroke | Brain Malformations

Symptom/Presentation: Abnormal Gait | Health Maintenance and Disease Prevention | Weakness

Specialty: Critical Care | Emergency Medicine |
Neurology / Neurosurgery

Age: Preschooler

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Brain Malformations and Stroke.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Rudolph CD, et.al. Rudolph’s Pediatrics. 21st edit. McGraw-Hill, New York, NY. 2003:2231-2232.

Ibrahimi DM, Tamargo RJ, Ahn ES. Moyamoya disease in children. Childs Nerv Syst. 2010 Oct;26(10):1297-308.

Mallick AA, O’Callaghan FJ. Risk factors and treatment outcomes of childhood stroke. Expert Rev Neurother. 2010 Aug;10(8):1331-46.

Smith ER, Scott RM. Moyamoya: epidemiology, presentation, and diagnosis. Neurosurg Clin N Am. 2010 Jul;21(3):543-51.

Munot P, Crow YJ, Ganesan V. Paediatric stroke: genetic insights into disease mechanisms and treatment targets. Lancet Neurol. 2011 Mar;10(3):264-74.

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