IGHE and Lymphadenopathy: However, with the goal of understanding the role of diminished IgE in the general population, certain clinical findings (e.g. presence of lymphadenopathy, splenomegaly) and laboratory tests (e.g. presence of tumour markers [114], C-reactive protein level [115], DNA methylation test [116], cell frequency detection [117], proteome and miRNome profiling [118], presence of circulating exosomes [119]) may be considered as directions for future studies in these patients.