CD40LG and Q fever: Serological testing was compatible with Q-fever in transition from acute to chronic disease, with phase I antibodies and high titers of phase II antibodies being present (phase I: immunoglobulin (Ig)G, 1600; IgA, 80; IgM, 320; phase II: IgG, 25,600; IgA, 640; IgM, 640).