Abstract
Purpose: :
Generally, ELISA and Western blot systems are used as standard testing for Borrelia, not distinguishing immunity from ongoing infection. In contrast to this established method the QuantiFERON-Lyme© (QFL), an Interferon gamma release test, measures T-cell activity as a measure for ongoing immunological activity. For this reason we want to retest our positive ELISA/Western blot patients by QFL.
Methods: :
A computer search of the hospital system was performed to identify all patients where serology for Borrelia subspecies was ordered from September 2005 to date. Positive ELISA results were confirmed by Western blot testing. The positive bands in Western Blot IgG or IgM assay were evaluated and those patients retested by QFL. Probability of diagnosis as well as correlation to uveitis subtype were determined. SUN criteria were applied for anatomical location.
Results: :
We ordered serology testing for Borrelia in 150 patients. Out of these, 15 (10%) were positive in ELISA and confirmed by Western blot. Three patients had another explanation for their uveitis than Borrelia and were excluded from the study.Of the remaining patients 9 were positive for IgG (6%) and 3 for IgM (2%).Out of the group with the positive IgG titer 8 showed a pattern of bands in the Western Blot that may equally indicate a clinically manifest Borreliosis or a state after therapy or spontaneously healed disease. One patient showed a Western blot band pattern of a possible early stage of disease. At the moment the QFL is in progress.
Conclusions: :
With the QFL a completely different aspect of immunological activity is examined. This is important as sera from blood donors show seroprevalence for Borrelia IgG in 6% and for IgM in 7%. In our study 8% of the patients with uveitis had a positive serology, a frequency that corresponds to the normal spread of Borrelia in the southern german population. Consequently serology results for Borrelia have to be interpreted with caution. QFL may be a better instrument to distinguish between past and active disease and could be helpful to make a treatment decision in the western blot positive patients.
Keywords: uveitis-clinical/animal model • bacterial disease • clinical laboratory testing