Parkinson's Disease Diagnosed by Salivary Gland Biopsy

Taken from Wikipedia

Currently, diagnosing Parkinson's Disease (a degenerative neurological disorder) is hard, usually a clinical exam and assessment of symptoms by a neurologist with at best about an 80% accuracy rate. There is no "test" per se that can diagnose Parkinson's Disease... until possibly now.

According to a study released in advance of its presentation at the annual meeting of the American Academy of Neurology, which will be held from March 16 to 23 in San Diego, Mayo Clinic researchers have determined a submandibular gland biopsy can offer 82% certainty whether a living patient has Parkinson's Disease or not. What is so special about this particular gland located under the jawline?

In patients with Parkinson's Disease, an uniquely abnormal protein called alpha-synuclein protein can be found.

In order to "biopsy" the submandibular gland which produces saliva, it does require a head and neck surgeon given the gland's location under the jawline. Beyond the usual risks of bleeding and infection present with any type of surgery, additional risks with this biopsy include:

• Permanent lip paralysis as the nerve that goes to the lower lip is located right over this gland.
• Permanent tongue paralysis as the nerve that moves the tongue is located right under this gland.
• Permanent numbness of the mouth floor as the nerve that provides sensation in this location is also located right under the gland.

Also, there are questions that need to be answered before this test is available more widely including:

How early in the Parkinson's Disease will this protein accumulate in the submandibular gland? If there is an "accumulation" time period, when is the best time to do the biopsy than?

Does the biopsy require a bloc of tissue or can a needle biopsy be sufficient (thereby reducing some of the surgical risks)?

Will insurance pay for this procedure?

Also, when is the paper going to be published regarding these results and can others replicate these findings? Here's the presentation abstract...

Source:
New saliva gland test may better diagnose patients with Parkinson's. FoxNews 1/11/13

Salivary Gland Biopsy as a Diagnostic Test for Parkinson's Disease. AAN 65th Annual Meeting Abstract

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Saliva Test for Laryngopharyngeal Reflux (LPR)

Various groups have been developing a fast, cheap, non-invasive saliva swab test to determine whether laryngopharyngeal reflux (LPR) is present or not. LPR may cause symptoms of:

• Hoarseness
• Chronic (ongoing) cough
• Frequent throat clearing
• Constant mucus or phelgm in the throat
• Dry or sandpaper like sensation in the throat
• Pain or burning sensation in the throat
• Feeling of a lump in the throat (globus pharyngeus)
• Problems swallowing
• Bad/bitter taste in the mouth (especially in morning)
• Asthma-like symptoms
• Ear pain and/or persistent ear infections
• Post-nasal drip
• Large lingual tonsils

When you compare a spit test to the current way of how reflux is determined via barium swallow, upper endoscopy (EGD), and 24 hour ph/impedance testing, it sounds quite attractive.

How does such a test work?

It basically looks for a stomach protein called pepsin.

Given reflux is when stomach contents moves up towards the mouth and pepsin is a protein ONLY produced in the stomach... pepsin should NOT be found in the throat/mouth.

As such, the test can state yes or no whether LPR is present or not.

How good is the test?

Depending on the study, sensitivity ranges in the 80-100% (can actually detect reflux if truly present) and specificity is around 85% (truly no reflux if test is negative).

Unfortunately, such testing is not offered is most labs. (Currently working on getting such testing available in our office.)

One test company is rdbiomed using their Peptest kit.

References:

Sensitive pepsin immunoassay for detection of laryngopharyngeal reflux. Laryngoscope. 2005 Aug;115(8):1473-8.

Rapid salivary pepsin test: Blinded assessment of test performance in gastroesophageal reflux disease. Laryngoscope. 2012 Jun;122(6):1312-6. doi: 10.1002/lary.23252. Epub 2012 Mar 23.

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