每日一题_2023.06.20

While hospitalized for treatment of an episode of aspiration pneumonia, a 45-year-old man begins to have episodes of severe non-bloody diarrhea and lower abdominal pain. Temperature is 38°C (100.4°F). CT of the abdomen and pelvis with oral and intravenous contrast demonstrates marked diffuse colonic thicken- ing (see image). What is the pathophysiology of the most likely cause of this patient’s condition?

在因吸入性肺炎住院治疗期间，一名45岁男性开始出现重度非血性腹泻和下腹痛。温度为38°C。腹部和盆腔CT口服和静脉造影显示明显的弥漫性结肠增厚(见图片)。该患者病情最可能的原因是什么病理生理学?

(A) Directly damages the microvilli of the enterocytes but does not invade直接破坏肠上皮细胞的微绒毛，但不侵入

(B) Produces an exotoxin that can induce cytokine release and cause hemolytic uremic syndrome)产生可诱导细胞因子释放并引起溶血性尿毒症综合征的外毒素

(C) Produces an exotoxin that increases the secretory activity of enterocytes产生一种增加肠细胞分泌活性的外毒素

(D) Produces an exotoxin that kills enterocytes 产生杀死肠细胞的外毒素

(E) Produces both heat-stable and labile toxins that promote secretions in the intestines产生热稳定和不稳定的毒素，促进肠道内的分泌物

答案解析：

该患者的症状和先前的住院提示为假膜性大肠杆菌炎。艰难梭菌增殖产生一种杀死肠细胞的外毒素，从而引起与伪膜性结肠炎相关的重度非血性腹泻。抗生素治疗抑制胃肠道的正常菌群，使艰难梭菌繁殖。克林霉素是第一种与艰难梭菌胃肠炎相关的抗生素，用于治疗膈肌以上的厌氧菌感染，如吸入性肺炎。然而，从那时起，许多抗生素被牵连，特别是头孢菌素和氨苄西林。对于近期使用抗生素的胃肠炎患者，应考虑艰难梭菌。

正确答案：D