Detection of IFN-ɣ Secretion in Blood Samples Collected Before and After Treatment of Varying Stages of Lyme Disease.

Background QuantiFERON ELISA with Borrelia burgdorferi peptide antigens was previously shown to reliably detect IFN-γ in blood samples from adult patients with early Lyme disease and the response disappeared rapidly after treatment. We evaluated the response before and after appropriate antibiotic therapy in adolescent and adult subjects with more diverse stages of the illness. Methods Blood was obtained from clinician-identified Lyme disease patients with constitutional complaints, erythema migrans, nerve palsy, cardiac abnormality, or arthritis before (n = 68) and 6 weeks (n = 46) and 6 months (n = 45) after therapy. The sera were tested for Lyme disease by standard two-tiered testing (STTT) and anti-C6 antibodies by ELISA and the levels of IFN-γ in the blood samples were detected by QuantiFERON ELISA. Results A positive STTT result supported the clinical diagnosis of 37 (54%) subjects and anti-C6 antibodies were detected in 45 (66%) subjects, including 36 (97%) STTT-positive subjects, and the responses often persisted or expanded after antibiotic therapy. IFN-γ was detected in 49 (72%) subjects prior to treatment and the response most often significantly decreased 6 weeks (P = 0.007) or 6 months (P = 0.001) after treatment. Conclusions The QuantiFERON ELISA reliably detected IFN-γ in blood samples from adult and adolescent patients with varying stages of Lyme disease and the response disappeared rapidly after treatment. Additional studies to more critically evaluate clinical utility as a laboratory test for diagnosis and confirmation of effective therapy are warranted.