CD40LG and Lyme disease: In the IDEIA Lyme Neuroborreliosis test, nine (17 %) of the 52 patients with definite LNB had elevated anti-Borrelia IgM AI alone, 11 (21 %) had only elevated anti-Borrelia IgG AI and 28 (54 %) patients had elevated AI for both anti-Borrelia IgM and IgG.