IFNG and cholesteryl ester measurement: Rigano et al. reported a higher serum level of Interleukin-4 (IL-4) and IL-10 in patients who did not respond to therapy compared to those who responded; Bayraktar et al. showed higher concentrations of IL-2, IL-4, and IL-10 in CE patients before treatment compared to those who were treated and to healthy controls; Mezioug and Touil-Boukoffa observed the coexistence of elevated levels of Interferon-γ (IFN-γ), IL-12, IL-16, IL-18, IL-4, IL-5, IL-10, and IL-13 in most sera of CE patients compared to healthy controls [11–13].