The diagnosis is stroke...

wait how old is the patient?

In morning report we discussed a patient who presented with a history of expressive aphasia and right sided weakness.

If this patient were 80 years old with atrial fibrillation not anticoagulated, or if they had multiple vascular risk factors, then it would be a common case of ischemic stroke that we encounter not infrequently.

How would your diagnostic consideration change if this patient were 20, 30 or 40 years old?

In other words, how do you approach stroke in the young?

Before we explore that, remember to be diligent with your neurologic history to clarify:
1. time course
2. characteristics
3. localization
4. associated symptoms (important, and should revolve around your DDx).

This patient had difficulty speaking, remember that when assessing for a language problem, try to distinguish if there is a deficient in comprehension, repetition, naming, or fluency. Language localizes to the left perisylvian region.

The time course was over a couple days with primarily language deficits and mild weakness (later confirmed on exam). There were no obvious assoicated symptoms that we will explore in detail later.

Physical examination should be meant to help confirm/disconfirm your working diagnosis that was made from your history. Remember that the neurologic exam starts with:

1. Mental status: Language is part of the mental status exam
then:
2. Cranial Nerves
3. Motor: not just power!
4. Reflexes
5. Sensory
6. Coordination

This patient's physical exam confirmed word-finding difficulties and mild right sided weakness with no other abnormalities found on exam.

Imaging revealed a left MCA territory infarct and this patient is currently being managed and worked up to determine the etiology of the stroke.

A word on neuro-imaging (I am not a radiologist by any means, but some useful tips...in a sense radiology for dummies 101):

CT findings for stroke include: loss of grey/white matter differentiation, ribboning, sulcal effacement, MCA sign.
When looking at an MRI for stroke, one approach is first look at the FLAIR sequence...a stroke is white. Then look at the DWI (look at the 2nd or 3rd sequence), stroke should still be white...lastly look at the ADC: stroke will be black.

This patient was young, and getting back to the diagnostic approach for "Stroke in the Young".

Remember to consider the causes you normally would and so looking for vascular disease, arrythmia (atrial fibrillation) is still part of the work up.

Other etiologies and clues:

1. Arterial:
- Consider dissection, especially if there is a history of trauma, or neck manipulation, and especially if you detect a Horner's.
- Arterial embolism can result  from hypercoaguable states (thrombophilias, PV, APLA) as well as from emboli from other sources such as endocarditis.
- Consider other arteriopathies such as moya-moya 

2. Venous
- Venous sinus thrombosis can occur, especially in the setting of risk factors such as high estrogen containing OCP, and consider in a young patient with stroke complaining of headache.

3. Cardiac
- as previously mentioned endocarditis (both infectious and non- ie Libman-Sacks endocarditis in SLE)
- Cardiac anomalies, ventricular or atrial thrombi, PFO (controversial)

4. Medications
- In particular think of illicit drug use, such as stimulants that may further put at risk for hypertension, dissection.

5. Thrombophilia
- Includes myeloproliferative disorders, I also think of sickle cell here (though perhaps not a true thrombophilia), PNH, APLA, hyperhomocysteine, as well as other causes that can be investigated. 

6. Infectious causes of stroke
- Discussed endocarditis
- Also VZV, TB, Nocardia, neurocysticercosis
- Rheumatic disease, or Chagas as cause for cardioembolism.

7. Rarer things
- Genetic disorders (MELAS, CADASIL), primary vasculitis less commonly present with stroke with exception of APLA.

The differential as can be seen needs to be expanded when a "young" patient has a stroke, history and physical will still guide you to effectively investigate and manage.

See this review article in the Lancet for details.