

A test with a high sensitivity – being the percentage true positives among patients with the target condition – will result in a low percentage of false negatives. A test with a high specificity – which is the percentage true negative results among patients without the target condition – will result in a low percentage of false positives. It also implies that falsely negative tested patients (who have the disease, but test negative) will not be treated for Lyme borreliosis. This implies that false positively tested patients (who have no Lyme borreliosis, but have positive serology) will be treated for Lyme borreliosis while they have another condition. After negative serology – a negative ELISA or a positive ELISA followed by a negative immunoblot – patients will not be treated for Lyme borreliosis, but they will be followed up or referred for further diagnosis. In such a situation, patients may be treated with antibiotics after a positive serology result – a positive ELISA possibly followed by a positive immunoblot. If signs and symptoms are inconclusive, the decision may be driven by the serology test results. ELISAs are the first test to be used immunoblots are typically applied only when ELISA was positive. Serological tests that are most often used are enzyme-linked immunosorbent assays (ELISAs) or immunoblots. Serology is the cornerstone of Lyme laboratory diagnosis, both in primary care and in more specialized settings. Laboratory confirmation is essential in case of non-specific disease manifestations. The diagnosis of Lyme borreliosis is based on the presence of specific symptoms, combined with laboratory evidence for infection. the disorder that a test tries to determine, as they affect different body parts and different organ systems, and because the patients suffering from these conditions may enter and travel through the health care system in different ways, hence following different clinical pathways. Each of these clinical presentations can be seen as a distinct target condition, i.e. In Europe, at least five genospecies of the Borrelia burgdorferi sensu lato complex can cause disease, leading to a variety of clinical manifestations including erythema migrans (EM), neuroborreliosis, arthritis and acrodermatitis chronica atrophicans (ACA). It is caused by spirochetes of the Borrelia burgdorferi sensu lato species complex, which are transmitted by several species of Ixodid ticks. Its incidence varies between countries, with approximately 65,500 patients annually in Europe (estimated in 2009). Lyme borreliosis is one of the most prevalent vector-borne diseases in Europe. Future diagnostic accuracy studies should be prospectively planned cross-sectional studies, done in settings where the test will be used in practice. The usefulness of the serological tests for Lyme disease depends on the pre-test probability and subsequent predictive values in the setting where the tests are being used. The observed heterogeneity and risk of bias complicate the extrapolation of our results to clinical practice. Two-tiered algorithms or antibody indices did not outperform single test approaches. Specificity was around 95 % in studies with healthy controls, but around 80 % in cross-sectional studies. Sensitivity was highly heterogeneous, with summary estimates: erythema migrans 50 % (95 % CI 40 % to 61 %) neuroborreliosis 77 % (95 % CI 67 % to 85 %) acrodermatitis chronica atrophicans 97 % (95 % CI 94 % to 99 %) unspecified Lyme borreliosis 73 % (95 % CI 53 % to 87 %). None of the studies had low risk of bias for all QUADAS-2 domains. Seventy-eight studies evaluating an Enzyme-Linked ImmunoSorbent assay (ELISA) or an immunoblot assay against a reference standard of clinical criteria were included. These were added as covariates to the model, to assess their effect on test accuracy. Potential sources of heterogeneity were test-type, commercial or in-house, Ig-type, antigen type and study quality. We used a hierarchical summary ROC meta-regression method for the meta-analyses. We assessed study quality using the QUADAS-2 checklist. Study selection and data-extraction were done by two authors independently. Studies evaluating the diagnostic accuracy of serological assays for Lyme borreliosis in Europe were eligible. We searched EMBASE en MEDLINE and contacted experts. We therefore systematically reviewed the accuracy of serological tests for the diagnosis of Lyme borreliosis in Europe. Interpretation of serological assays in Lyme borreliosis requires an understanding of the clinical indications and the limitations of the currently available tests.
