Qualman S J, Petric M, Karmali M A, Smith C R, Hamilton S R
Department of Laboratory Medicine, Children's Hospital, Columbus, Ohio 43205.
Am J Clin Pathol. 1990 Oct;94(4):410-6. doi: 10.1093/ajcp/94.4.410.
The direct involvement of Clostridium difficile in the lesional tissue of pseudomembranous colitis has not been demonstrated; the organism's effects have been assumed to be strictly toxin mediated. Because C. difficile cytotoxin may be found incidentally in the intestinal lumina of asymptomatic infants, the role of the organism in a variety of pediatric intestinal diseases is uncertain. The authors studied seven cases of fatal pediatric pseudomembranous colitis in which the presence of C. difficile was uniformly demonstrable in lesional tissues with the use of both an intestinal spore stain and a specific immunostain. The patients had either underlying Hirschsprung's disease or hematologic malignancy; the striking pathologic features peculiar to these patients were altered mucosal mucin and immunologic barriers in the former group and neutropenia in the latter. Two patients had demonstrable circulating cytotoxin in serum or ascitic fluid, and C. difficile was identified invading colonic mucosa or submucosa. Such phenomena did not occur in control pediatric patients with multiple other intestinal lesions. Altered host factors may be responsible for the intestinal invasion of C. difficile and its systemic toxin circulation in cases of fatal pediatric pseudomembranous colitis.
艰难梭菌在伪膜性结肠炎病变组织中的直接参与尚未得到证实；该病原体的作用被认为完全是由毒素介导的。由于在无症状婴儿的肠腔中可能偶然发现艰难梭菌细胞毒素，所以该病原体在多种儿科肠道疾病中的作用尚不确定。作者研究了7例致命性儿科伪膜性结肠炎病例，通过肠道芽孢染色和特异性免疫染色，在病变组织中均一致证实了艰难梭菌的存在。这些患者要么患有潜在的先天性巨结肠病，要么患有血液系统恶性肿瘤；前一组患者特有的显著病理特征是黏膜黏蛋白和免疫屏障改变，后一组患者则是中性粒细胞减少。两名患者的血清或腹水中可检测到循环细胞毒素，且已确定艰难梭菌侵入结肠黏膜或黏膜下层。在患有多种其他肠道病变的对照儿科患者中未出现此类现象。在致命性儿科伪膜性结肠炎病例中，宿主因素改变可能是艰难梭菌肠道侵袭及其全身毒素循环的原因。
