TNF and psychiatric disorder: It was reported that proinflammatory cytokines, including interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), are involved in the etiologies of mental disorders.[21] Furthermore, elevated Hp IgG levels were significantly associated with increased serum IL-6 levels among Hp-infected individuals.[22] We measured the IL-1β concentration of preserved analyzable serum in some patients (N = 10); however, we noted no significant differences in the concentration between the Hp eradication success group and failure group (data not shown).