BACKGROUND The etiology of ulcerative colitis (UC) remains elusive even though many genetic and environmental pathogenic factors have been reported. Aberrant inflammatory responses mediated by specific subsets of T cells have been observed in ulcerative lesions of UC patients. OBJECTIVES To elucidate the involvement of a delayed-type hypersensitivity reaction in UC, we focused on dental metal hypersensitivity, a T cell-mediated, delayed-type allergic reaction that causes oral contact mucositis and systemic cutaneous inflammation. METHOD We recruited 65 Japanese UC patients and 22 healthy controls (HC) and used the in vitro lymphocyte stimulation test to quantify their sensitivity to zinc, gold, nickel, and palladium - the metals that have been widely used in dentistry. All subjects were users of metallic dental implants and/or prostheses containing zinc, gold, nickel, and/or palladium as major constituents. RESULTS Sixty percent of the UC patients were hypersensitive to at least one metal species, whereas 32% of the HC were hypersensitive to only a single metal species. The overall incidence of metal hypersensitivity was significantly higher for UC patients than for HC. Furthermore, a significantly greater proportion of UC patients were hypersensitive to nickel or palladium. The severity of the sensitivity to nickel and palladium was also significantly greater for UC patients than for HC. CONCLUSIONS This pilot study demonstrates that UC patients have a significantly higher incidence of hypersensitivity to nickel and palladium, suggesting the possible involvement of dental metal hypersensitivity in UC pathogenesis.

中文翻译：

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溃疡性结肠炎患者镍和钯超敏反应的患病率较高。

背景技术尽管已经报道了许多遗传和环境致病因素，但溃疡性结肠炎（UC）的病因仍然难以捉摸。在UC患者的溃疡性病变中已经观察到由T细胞的特定亚群介导的异常炎症反应。目的为了阐明迟发性超敏反应在UC中的参与，我们集中于牙科金属超敏反应，一种引起口腔接触性粘膜炎和全身性皮肤炎症的T细胞介导的迟发性过敏反应。方法我们招募了65位日本UC患者和22位健康对照（HC），并使用体外淋巴细胞刺激测试来量化他们对锌，金，镍和钯（已广泛用于牙科的金属）的敏感性。所有受试者都是使用以锌，金，镍和/或钯为主要成分的金属牙科植入物和/或假体的使用者。结果60％的UC患者对至少一种金属过敏，而HC的32％仅对一种金属过敏。UC患者金属超敏反应的总体发生率显着高于HC患者。此外，显着更大比例的UC患者对镍或钯过敏。UC患者对镍和钯的敏感性的严重性也显着高于HC患者。结论这项初步研究表明，UC患者对镍和钯超敏反应的发生率明显更高，