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Stroke Main page

Patient Information




Hemorrhagic stroke
Ischemic stroke

Differential Diagnosis

Epidemiology and Demographics


NIH stroke scale
Glasgow coma scale

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Seyedmahdi Pahlavani, M.D. [2]Aysha Aslam, M.B.B.S[3],Tarek Nafee, M.D. [4],Sara Mehrsefat, M.D. [5]


Stroke is the rapidly developing loss of brain functions due to a disturbance in the blood vessels supplying blood to the brain. This can be due to ischemia (lack of blood supply) caused by thrombosis or embolism, or due to a hemorrhage.[1]

Stroke is a medical emergency and can cause permanent neurological damage, complications and death if not promptly diagnosed and treated. It is the third leading cause of death and the leading cause of adult disability in the United States and Europe. It is predicted that stroke will soon become the leading cause of death worldwide.[2] WHO defines stroke as, a neurological deficit of cerebrovascular cause that persists beyond 24 hours or is interrupted by death within 24 hours.

Risk factors for stroke include advanced age, hypertension (high blood pressure), previous stroke or transient ischaemic attack (TIA), diabetes mellitus, high cholesterol, cigarette smoking, atrial fibrillation, migraine[3] with aura, and thrombophilia. In clinical practice, blood pressure is the most important modifiable risk factor of stroke; however many other risk factors, such as cigarette smoking cessation and treatment of atrial fibrillation with anticoagulant drugs, are important. Treatment of ischemic stroke is occasionally with thrombolysis, but usually with supportive care (physiotherapy and occupational therapy) and secondary prevention with antiplatelet drugs (aspirin and often dipyridamole), blood pressure control, statins and anticoagulation (in selected patients).[4] Hemorrhagic stroke is a medical emergency, rapid diagnosis and management is crucial because early deterioration is common in the first few hours after ICH onset.[5]


The following table lists causes for stroke.[6][7][8][9][10][11][12][13][14][15]

Disease Lethal causes Common causes Less common causes
Transient ischemic attack (TIA) Emboli from cardiac source (mostly secondary to AF) Arterial dissection
Ischemic stroke
Intracerebral hemorrhage ---
Subarachnoid hemorrhage

Rupture of an aneurysm

Rupture of an aneurysm

Subdural hemorrhage Rupture of bridging vessels Trauma (motor vehicle accidents, falls, and assaults)
Epidural hemorrhage Rupture of middle meningeal arteries Trauma (motor vehicle accidents, falls, and assaults)
Intraparenchymal hemorrhage --- Trauma (motor vehicle accidents, falls, and assaults) Rupture of an aneurysm

Arteriovenous malformation

Intraventricular hemorrhage (IVH) ---


Transient ischemic attack

  • A transient ischemic attack is caused by the temporary disturbance of blood supply to a restricted area of the brain, resulting in brief neurologic dysfunction that usually persists for less than 24 hours.


Large vessel thromboembolism
Small vessel or Lacunar infarct
Intracerebral (ICH)
Subarachnoid hemorrhage (SAH)
Subdural Hemorrhage
Epidural Hemorrhage
Intraparenchymal hemorrhage
Intraventricular hemorrhage (IVH)
Cerebral microbleeds

Differential diagnosis

Diseases Symptoms Physical Examination Past medical history Diagnostic tests Other Findings
Headache LOC Motor weakness Abnormal sensory Motor Deficit Sensory deficit Speech difficulty Gait abnormality Cranial nerves CT /MRI CSF Findings Gold standard test
Brain tumor[16] + - - - + + + - + Weight loss, fatigue + Cancer cells[17] MRI Cachexia, gradual progression of symptoms
Hemorrhagic stroke + + + + + + + + - Hypertension + - CT scan without contrast[18][19] Neck stiffness
Subdural hemorrhage + + + + + - - - + Trauma, fall + Xanthochromia[20] CT scan without contrast[18][19] Confusion, dizziness, nausea, vomiting
Neurosyphilis[21][22] + - + + + + - + - STIs + Leukocytes and protein CSF VDRL-specifc

CSF FTA-Ab -sensitive[23]

Blindness, confusion, depression,

Abnormal gait

Complex or atypical migraine + - + + - - + - - Family history of migraine - - Clinical assesment Presence of aura, nausea, vomiting
Hypertensive encephalopathy + + - - - - + + - Hypertension + - Clinical assesment Delirium, cortical blindness, cerebral edema, seizure
Wernicke’s encephalopathy - + - - - + + + + History of alcohal abuse - - Clinical assesment and lab findings Ophthalmoplegia, confusion
CNS abscess + + - - + + + - - History of drug abuse, endocarditis, immunosupression + leukocytes, glucose and protien MRI is more sensitive and specific High grade fever, fatigue,nausea, vomiting
Drug toxicity - + - + + + - + - - - - Drug screen test Lithium, Sedatives, phenytoin, carbamazepine
Conversion disorder + + + + + + + + History of emotional stress - - Diagnosis of exclusion Tremors, blindness, difficulty swallowing
Metabolic disturbances (electrolyte imbalance, hypoglycemia) - + + + + + - - + - - Hypoglycemia, hypo and hypernatremia, hypo and hyperkalemia Depends on the cause Confusion, seizure, palpitations, sweating, dizziness, hypoglycemia
Meningitis or encephalitis + - - - - + + - - History of fever and malaise - Leukocytes,


↓ Glucose

CSF analysis[24] Fever, neck


Multiple sclerosis exacerbation - - + + - + + + + History of relapses and remissions + CSF IgG levels

(monoclonal bands)

Clinical assesment and MRI [25] Blurry vision, urinary incontinence, fatigue
Seizure + + - - + + - - + Previous history of seizures - Mass lesion Clinical assesment and EEG [26] Confusion, apathy, irritability,
Diseases History and Physical Diagnostic tests Other Findings
Motor Deficit Sensory deficit Cranial nerve Involvement Autonomic dysfunction Proximal/Distal/Generalized Ascending/Descending/Systemic Unilateral (UL)

or Bilateral (BL)


No Lateralization (NL)

Onset Lab or Imaging Findings Specific test
Adult Botulism + - + + Generalized Descending BL Sudden Toxin test Blood, Wound, or Stool culture Diplopia, Hyporeflexia, Hypotonia, possible respiratory paralysis
Infant Botulism + - + + Generalized Descending BL Sudden Toxin test Blood, Wound, or Stool culture Flaccid paralysis (Floppy baby syndrome), possible respiratory paralysis
Guillian-Barre syndrome[27] + - - - Generalized Ascending BL Insidious CSF: ↑Protein


Clinical & Lumbar Puncture Progressive ascending paralysis following infection, possible respiratory paralysis
Eaton Lambert syndrome[28] + - + + Generalized Systemic BL Intermittent EMG, repetitive nerve stimulation test (RNS) Voltage gated calcium channel (VGCC) antibody Diplopia, ptosis, improves with movement (as the day progresses)
Myasthenia gravis[29] + - + + Generalized Systemic BL Intermittent EMG, Edrophonium test Ach receptor antibody Diplopia, ptosis, worsening with movement (as the day progresses)
Electrolyte disturbance[30] + + - - Generalized Systemic BL Insidious Electrolyte panel ↓Ca++, ↓Mg++, ↓K+ Possible arrhythmia
Organophosphate toxicity[31] + + - + Generalized Ascending BL Sudden Clinical diagnosis: physical exam & history Clinical suspicion confirmed with RBC AchE activity History of exposure to insecticide or living in farming environment. with : Diarrhea, Urination, Miosis, Bradycardia, Lacrimation, Emesis, Salivation, Sweating
Tick paralysis (Dermacentor tick)[32] + - - - Generalized Ascending BL Insidious Clinical diagnosis: physical exam & history - History of outdoor activity in Northeastern United States. The tick is often still latched to the patient at presentation (often in head and neck area)
Tetrodotoxin poisoning[33] + - + + Generalized Systemic BL Sudden Clinical diagnosis: physical exam & dietary history - History of consumption of puffer fish species.
Stroke[34] +/- +/- +/- +/- Generalized Systemic UL Sudden MRI +ve for ischemia or hemorrhage MRI Sudden unilateral motor and sensory deficit in a patient with a history of atherosclerotic risk factors (diabetes, hypertension, smoking) or atrial fibrillation.
Poliomyelitis[35] + + + +/- Proximal > Distal Systemic BL or UL Sudden PCR of CSF Asymmetric paralysis following a flu-like syndrome.
Transverse myelitis[36] + + + + Proximal > Distal Systemic BL or UL Sudden MRI & Lumbar puncture MRI History of chronic viral or autoimmune disease (e.g. HIV)
Neurosyphilis[21][22] + + - +/- Generalized Systemic BL Insidious MRI & Lumbar puncture CSF VDRL-specifc

CSF FTA-Ab -sensitive[23]

History of unprotected sex or multiple sexual partners.

History of genital ulcer (chancre), diffuse maculopapular rash.

Muscular dystrophy[37] + - - - Proximal > Distal Systemic BL Insidious Genetic testing Muscle biopsy Progressive proximal lower limb weakness with calf pseudohypertrophy in early childhood. Gower sign positive.
Multiple sclerosis exacerbation[38] + + + + Generalized Systemic NL Sudden CSF IgG levels


Clinical assessment and MRI [25] Blurry vision, urinary incontinence, fatigue
Amyotrophic lateral sclerosis[39] + - - - Generalized Systemic BL Insidious Normal LP (to rule out DDx) MRI & LP Patient initially presents with upper motor neuron deficit (spasticity) followed by lower motor neuron deficit (flaccidity).
Inflammatory myopathy[40] + - - - Proximal > Distal Systemic UL or BL Insidious Elevated CK & Aldolase Muscle biopsy Progressive proximal muscle weakness in 3rd to 5th decade of life. With or without skin manifestations.

Epidemiology and Demographics

Stroke in USA

  • Stroke is a leading cause of serious long-term disability
  • In USA, the incidence and mortality rates of stroke has significantly decreased compared to previous years.
  • From year 2003 to 2013, the mortality rates due to stroke declined by 18.5%.[41]
  • In 2013, stroke became the fifth leading cause of death.
  • The case fatality rate of stroke is estimated to be 41.7 deaths per 100, 000 population[41]
  • The incidence of new (610, 000) or recurrent stroke (185, 000) is estimated to be 795000 people annually or 250 cases per 100, 000.[41]
  • It is estimated that one incidence of stroke happens every 4 sec with death occurs every 4 min.[41]
  • About 87% of all strokes are ischemic strokes[42]
  • Stroke costs the United States an estimated $34 billion each year[42]


  • According to WHO, the incidence of stroke is estimated to be 15 million people annually, worldwide.[43].
  • Out of these, 5 million die and 5 million are left permanently disbaled.[43].


  • Stroke can occur in all age groups. However, the incidence of stroke is less among individuals age less than 40 years of age and the risk increases with increasing age. [42]
  • According to WHO, stroke also occurs in about 8% of children with sickle cell disease.[43].
  • In 2009, 34% of people hospitalized for stroke were younger than 65 years[42]
  • The incidence of stroke in people aged 18 to 50 years is estimated to be approximately 10%. [41]
  • The rate of decline in mortality rates of stroke in different age groups is as follows:[41]
    • Older then 65 years: from 534.1 to 245.2 per 100,000
    • 45-65 years of age: from 43.5 to 20.2 per 100,000
    • 18 to 44 years of age: from from 3.7 to 2.0 per 100,000


There is increased incidence of stroke in men as compared to women.


  • The risk of incidence of first stroke is twice in African-American population as compared to Caucasians with increased mortality rates.[42]

Geographical distribution

  • There is increased incidence and mortality rates of stroke in developing countries as compared to developed countries due to low socioeconomic status and heath facilities.
  • In the USA, the highest death rates from stroke are in the southeastern United States.[42]


Almost 10% of cerebrovascular events that present to the emergency department are not detected during evaluation.[44] This is more common when "presenting neurologic complaints are mild, nonspecific, or transient".[44]

  • Diagnosis is based on history of symptoms development, physical examination and imaging findings.
  • CT scan and magnetic resonance imaging (MRI) are both reasonable for initial evaluation.
  • CT scan without contrast is the initial test performed to diagnose ischemic stroke and rule out hemorrhagic stroke.
  • CT is very sensitive for identifying acute hemorrhage and is considered the gold standard.
  • Gradient echo and T2 susceptibility-weighted MRI are as sensitive as CT for detection of acute hemorrhage and are more sensitive for identification of prior hemorrhage.
  • MR diffusion weighted imaging is the most sensitive and specific test for diagnosing ischemic stroke and may help detect presence of infarction in few minutes of onset of symptoms. It may also help differentiate viable tissue from infarct area if combined with MR perfusion. For diagnosing ischemic stroke in the emergency setting, MRI scan has the sensitivity and specificity of 83% and 98% respectively.[45]
  • MRI scan is superior to CT scan for being more sensitive and specific in detection of lacunar and posterior fossa infarcts, differentiation between acute and chronic stroke and detection of microbleeds. Another additional advantage is absence of ionising radiation compared to CT scan. Some of the disadvantages of MRI scan may include lack of availability in acute setting, higher cost, inability to use it in patients with metallic implants. MRI with contrast cannot be used in patients with renal failure.[46][47]


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