1760. Interferon Gamma Release Assay for Diagnosis of Lyme disease

Abstract Background The sensitivity of current antibody detection assays against Borrelia burgdorferi in the early stage of Lyme disease is very low. In children especially, who commonly have febrile viral illnesses, manifestations of early Lyme disease can be misdiagnosed. We previously demonstrated that IFNγ secretion could be detected in whole blood collected from Lyme disease patients at first clinical presentation following overnight incubation of the blood with peptides derived from B. burgdorferi. In the present study, we further evaluated the utility of IFNγ release for the laboratory diagnosis of Lyme disease in children with varying stages of the illness. Methods Children ages 2–18 years with no prior history of Lyme disease and with manifestations of Lyme disease at any stage were enrolled in the study. Sick and healthy controls were enrolled for comparison. We collected history and physical examination data and blood samples at the time of enrollment, at 1 month, and at 6 months. Standard 2-tier testing with ELISA (whole cell sonicate [WCS] and C6) and western blot were run in parallel to the IFNγ release assay for all blood samples. Sensitivity and specificity of the study assay were determined for presentation at all stages of Lyme disease. Clinical data were summarized. Results Blood samples from 22 patients with Lyme disease and 7 controls (4 sick, 3 healthy) were obtained at the first visit. The IFNγ release assay detected early and early disseminated Lyme disease with 78% sensitivity compared with 59% sensitivity of 2-tier testing in our study. For patients presenting with a single erythema migrans (EM) lesion, the IFNγ release assay detected Lyme disease with 63% sensitivity compared with 14% sensitivity with 2-tier testing. The IFNγ release assay had only 25% sensitivity for detecting late disease. A single control patient was positive for both the IFNγ release assay and 2-tier serology. Conclusion A novel IFNγ release assay demonstrated significantly increased sensitivity when compared with 2-tier testing in the laboratory diagnosis of Lyme disease in patients presenting with a single EM lesion. Future study is needed to determine its utility in detecting early Lyme disease in patients with nonspecific febrile illness in the absence of erythema migrans. Disclosures R. Dattwyler, Qiagen: Collaborator, Research support. P. Arnaboldi, Qiagen: Collaborator, research materials.