Unconventional diagnostic tests for Lyme borreliosis: a systematic review, 2019, Raffetin et al.

[ME/CFS Skeptic]

Abstract:

Background
Lyme borreliosis (LB) diagnosis currently relies mainly on serological tests and sometimes PCR or culture. However, other biological assays are being developed to try to improve Borrelia-infection diagnosis and/or monitoring.

Objectives
To analyse available data on these unconventional LB diagnostic assays through a systematic literature review.

Methods
We searched PubMed and Cochrane Library databases according to the PRISMA-DTA method and the Cochrane Handbook for Systematic Reviews of Interventions. We analysed controlled and uncontrolled studies (published 1983–2018) on biological tests for adults to diagnose LB according to the European Study Group for Lyme Borreliosis or the Infectious Diseases Society of America definitions, or identify strongly suspected LB. Two independent readers evaluated study eligibility and extracted data from relevant study reports; a third reader analysed full texts of papers to resolve disagreements. The quality of each included study was assessed with the QUADAS-2 evaluation scale.

Results
Forty studies were included: two meta-analyses, 25 prospective controlled studies, five prospective uncontrolled studies, six retrospective controlled studies and two case reports. These biological tests assessed can be classified as: (i) proven to be effective at diagnosing LB and already in use (CXCL-13 for neuroborreliosis), but not enough to be standardized; (ii) not yet used routinely, requiring further clinical evaluation (CCL-19, OspA and interferon-α); (iii) uncertain LB diagnostic efficacy because of controversial results and/or poor methodological quality of studies evaluating them (lymphocyte transformation test, interferon-γ, ELISPOT); (iv) unacceptably low sensitivity and/or specificity (CD57+ natural killer cells and rapid diagnostic tests); and (v) possible only for research purposes (microscopy and xenodiagnoses).

Discussion
QUADAS-2 quality assessment demonstrated high risk of bias in 25/40 studies and uncertainty regarding applicability for 32/40, showing that in addition to PCR and serology, several other LB diagnostic assays have been developed but their sensitivities and specificities are heterogeneous and/or under-evaluated or unassessed. More studies are warranted to evaluate their performance parameters. The development of active infection biomarkers would greatly advance LB diagnosis and monitoring.

Source: https://www.sciencedirect.com/science/article/pii/S1198743X1930388X

The reason for posting this review of Lyme tests from 2019, is that in Belgium and elsewhere, doctors have used some of these tests such as the LTT-test and CD57+ to diagnose chronic Lyme disease.

 

[duncan]

The reason for posting this review of Lyme tests from 2019, is that in Belgium and elsewhere, doctors have used some of these tests such as the LTT-test and CD57+ to diagnose chronic Lyme disease.

I suspect what they are trying to diagnose is Lyme disease. "Chronic" is nothing more than an adjective. Do they use "chronic"? Probably. At one time, pretty much everybody did, even IDSA-types in the US. It's just an adjective. However, it became politicized around the early 1990's, and remains so.

As for the efficacy of diagnostics which deviate from CDC recommendation, it's important to understand what the gold standard is. What it isn't is any antibody algorithm adopted by the CDC or its surrogates in other countries. The two-tier guideline is widely understood to have inadequacies in many circumstances, including early stage Lyme, sero-negative Lyme, cases of antigenic variation(I have had this), etc. It also isn't PCR for a host of reasons, but primarily for its relatively low S/S.

It's culture, and that is used successfully in a vanishingly small portion of diagnostic adventures - primarily when bulls-eye rashes are tested, which isn't even needed usually since EM's are diagnostic in and of themselves (unless you find yourself in the US midwest embroiled in the STARI debate).

What all this boils down to is that if your are a patient that suspects late stage Lyme, you may be out of luck as far as a universally validated, reliable diagnostic metric. Personally, though, I think it's a good thing people/companies are trying to build one.