Diagnostic use of the lymphocyte transformation test-memory lymphocyte immunostimulation assay in confirming active Lyme borreliosis in clinically and serologically ambiguous cases.

The aim of this study was to carry out an independent evaluation of the proposition that the lymphocyte transformation test-memory lymphocyte immunostimulation assay (LTT-MELISA) may be diagnostically useful in the confirmation of active Lyme borreliosis in clinically and serologically ambiguous cases. Blood samples from 54 patients consecutively presenting to a British center with clinical suspicion of Lyme borreliosis were tested for this disease by immunoglobulin M (IgM) and immunoglobulin G (IgG) Western blots and by LTT-MELISA. Forty-five of these patients had Western blot results which were negative for both IgM and IgG by the criteria of the Centers for Disease Control and Prevention (CDC); of these patients, 19 (42%) were LTT-MELISA-positive. Two of the patients who had IgM positive results by the CDC criteria were LTT-MELISA-negative. It is concluded that, for putative European-acquired Lyme borreliosis infections, it would be sensible to carry out both the LTT-MELISA and Western blot assay.