每日一题_2023.09.17

A 9-year-old boy is brought to the emergency department with a two-day history of abdominal pain, vomiting, and a rash. His mother re- ports that he had a runny nose and mild cough about a week ago. On examination there is diffuse abdominal tenderness and a rash over the arms and the legs. His complete blood cell count is within normal limits and urinalysis shows 12 RBCs/hpf, 2 WBCs/hpf, no protein, and no glucose. An image of the rash is shown in the image. What is the most likely etiology of this patient’s symptoms?

一名9岁男孩因腹痛、呕吐和皮疹2天被送到急诊科。他的母亲报告说，大约一周前他流鼻涕和轻度咳嗽。检查时腹部有弥漫性压痛，手臂和腿部有皮疹。他的全血细胞计数在正常范围内，尿液分析显示12个红细胞/高倍视野，2个白细胞/高倍视野，无蛋白质，无葡萄糖。图中显示了皮疹的图像。该患者症状最有可能的病因是什么?

(A)  Deficiency of von Willebrand factor- cleaving metalloproteinases血管性血友病因子裂解金属蛋白酶类缺乏

(B)  IgA antibody deposition in the mesangium系膜区IgA抗体沉积

(C)  IgA immune complexes deposited in small vesselsIgA免疫复合物沉积于小血管

(D)  IgG antibodies against platelets抗血小板IgG抗体

(E)  IgG antibodies deposited in the glomerular basement membraneIgG抗体沉积于肾小球基底膜

答案解析：

Henoch-Schönlein紫癜(HSP)是由IgA免疫复合物沉积引起的系统性血管炎。常继发于呼吸道感染，以紫癜、腹痛和肾小球肾炎三联征为特征。一些儿童还表现为主要关节关节炎。过敏性紫癜的皮疹通常描述为臀部和腿部可触及的紫癜。它是儿童最常见的小血管炎，很少影响成人。这种疾病是自限性的，治疗是支持性的。有相同症状的老年人更有可能患与抗中性粒细胞胞质抗体相关的血管炎

正确答案：C