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A tau protein test is used to confirm whether cerebrospinal fluid (CSF) is leaking from the brain.

CSF is a colourless fluid that surrounds and protects the brain and spinal cord.

Following a severe head injury, such as a skull fracture, the membranes that cover your brain and spine could tear. If this happens, CSF can leak out of the tear, causing a watery discharge from your ear or nose.

As tau protein is only found in CSF, testing for it will help rule out other fluids, such as nasal secretions and other bodily fluids.

Read more about the tau protein test at Lab Tests Online UK.

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Selected links

NHS 111 Wales links

Minor head injury

Severe head injury

External links

Lab Tests Online UK

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The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website
Last Updated: 14/04/2015 14:51:21