MGAM and rheumatoid arthritis: Many investigators have reported that c-C3 and α2-MG are not always specific for IBD, but rather the former could reflect the activity of other inflammatory diseases, such as vasculitis, glomerulosclerosis, and rheumatoid arthritis (Cosio and Hernandez, 1996; Crnogorac et al., 2018; Romano et al., 2018).