Protein Testing for Creutzfeldt-Jakob

Creutzfeldt-Jakob cerebrospinal fluid test has good accuracy if doctor is knowledgeable

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Creutzfeldt-Jakob disease (CJD) is a rare and fatal disease that is difficult to diagnose and often mistaken for neurodegenerative disorders or dementia. Accurate and efficient diagnosis is important so that the patient may seek care and make end of life preparations.

A recent study seeks to determine if the presence of 14-3-3 protein in cerebrospinal fluid can be used to identify sporadic CJD. The study showed that 14-3-3 testing had a moderately high precision of accuracy in predicting CJD when other factors and symptoms are also considered.

"Discuss all symptoms and medical history with your doctor."

Current CJD diagnosing techniques include brain biopsy, autopsy, magnetic resonance imaging (MRI), CT scan and spinal fluid testing. The 14-3-3 test looks for the presence of 14-3-3 protein in the spinal fluid.

Protein 14-3-3 was first described in studies of bovine brains. It was first thought to only exist in the brain, but studies have proven it may also exist in typically lower levels in other organs.

The protein is seen in higher levels in CJD patients than in the general population.

In the study, Taim Muayqil, MBBS, FRCPC, of the King Saud University in Riyadh, Saudi Arabia, along with colleagues from the University of Kansas Medical Center and University of Alberta, searched existing medical databases for 14-3-3 and CJD related literature.

All articles were published between 1995 and January 1, 2011. No animal studies were included and all study participants were at least 18 years old.

A total of 11,165 articles were reduced to 9 CJD relevant studies with high strength evidence and no bias.

The researchers concluded that 14-3-3 protein testing led to a moderately high diagnostic accuracy. The test was most useful when there is already a 20-90 percent chance of CJD.

The absence of higher than normal 14-3-3 protein may be helpful in concluding a patient does not have CJD. The presence of 14-3-3 may indicate CJD but does not rule out a possibly reversible form of dementia.

How useful the 14-3-3 test is ultimately depends on the knowledge and judgment of the medical professionals administering and monitoring the test.

Diagnosing medical professionals must consider the rarity of CJD, the practice setting, the symptoms and history of the patient and the results of any other tests.

In the future, standardization of the test, the existence of any combination of bio-markers and the addition of other technology like MRI could improve diagnostic techniques.

The study was published in Neurology.

Financial support for the study was provided by the American Academy of Neurology.

Some of the authors report associations with Neurology Now, Boehringer Ingelheim and the American Academy of Neurology.

Reviewed by: 
Review Date: 
October 10, 2012
Last Updated:
October 11, 2012