Early study, hopeful results.
The definite diagnosis of acute Lyme neuroborreliosis (LNB) requires detection of an increased Borrelia burgdorferi-specific antibody index (AI).
Testing for chemokine CXCL13 in comparison with the anti-borrelia antibody index (AI) found higher accuracy of detection and ability to detect earlier. Measurements by ELISA showed a CXCL13 sensitivity of 94.1% compared to AI of 85.7%. Since early detection and receiving early treatment is vital in fighting this disease, this is good news. As important as early detection is adequate length of treatment as well as abandoning assumptions of a bright line between acute and chronic.
CXCL13 is a chemokine, a small protein which has been associated with immune response by "encouraging" inflammation. This encouragement consists in directing surrounding cells to respond to chemicals in their environment, as in bacteria approaching glucose or cells fleeing toxins. In the case of CXCL13, by December of 2009 studies had suggested
a key role of CXCL13 in B cell migration to sites of infection as shown here for the CSF [cerebrospinal fluid] of LNB patients.
These proteins have been found in bacteria and viruses--should we test for B. dorferi chemokines directing response to our body's immune system? Here's hoping this helps some day soon.
CONCLUSIONS: CXCL13 shows high sensitivity and specificity for acute, untreated LNB [Lyme . This novel marker appears to be helpful in clinically atypical cases and, in particular, in early stages of the disease when the B. burgdorferi AI is (still) negative.
Other studies of CXCL13 as a marker for LNB. (h/t MsGrin)