直肠内脱垂致梗阻性排粪综合征患者直肠胶原纤维及弹性纤维的表达及意义

Expression of collagen and elastin fibers in the rectum of patients with obstructed defecation syndrome and its significance

目的检测直肠内脱垂致梗阻性排粪综合征（ODS）患者直肠黏膜下层胶原纤维及弹性纤维的表达情况，并探讨其在ODS发生机制中的可能作用。方法收集中山大学附属第六医院2012年1月至2014年12月间经肛吻合器直肠切除术（STARR）治疗的20例ODS患者的手术标本，并以同期因Ⅲ一Ⅳ度痔行STARR术治疗的20例患者的手术标本作为对照。取直肠全层进行Masson染色和EVG染色，观察直肠胶原纤维与弹性纤维的变化，并以Image—ProPlus6．0软件分析胶原纤维和弹性纤维所占面积比。结果Masson染色显示，与对照组相比，ODS患者直肠黏膜下层胶原纤维表达量较对照组明显减少，且结构纤细，其所占面积比对照组明显减少[（13．88±7．02）％比（30．98±3．46）％，P〈0．01]。EVG染色也显示，ODS患者胶原纤维所占面积比对照组明显减少[（17．18±7．24）％比（27．04±9．65）％，P〈0．01]。同时，EVG染色显示，ODS患者直肠黏膜下层弹性纤维数量减少，且多呈断裂碎片状，其所占面积比对照组也有所减少[（1．20±1．39）％比（1．47±1．06）％]，但差异未达到统计学意义（P〉0．05）。结论直肠黏膜下层胶原纤维和弹性纤维表达异常可能是ODS发病机制中的重要因素，尤以胶原纤维表达异常为著。

Objective To detect the expression of collagen and elastin fibers in the rectum of patients with obstructive defecation syndrome （ODS）, and to explore the possible role of these fibers in the pathogenesis of ODS. Methods The rectum specimens of 20 patients with ODS were collected. These patients had undergone stapled transanal rectal resection （STARR） surgery in our hospital since 2012. Full-thickness rectal specimens were stained with Masson and EVG staining to show collagen and elastin fibers. As the control, rectum specimens of 20 patients with severe prolapsed hemorrhoids also undergoing STARR surgery in our hospital during the same period were collected. Results Masson staining showed that the structure of collagen fibers in submucosa was slender, area decreased [ （13.88± 7.02）% vs. （30.98±3.46）%, P〈0.01 ], and the expression level was significantly lower in ODS group compared with control group. EVG staining also showed that collagen fiber area of ODS patients was reduced compared with control group [（17.18±7.24）% vs. （27.04±9.65）%, P〈0.01]. Meanwhile EVG staining revealed that elastic fibers were fragmented in ODS group and the expression level was lower compared with control group [（1.20±1.39）% vs. （1.47±1.06）%], whereas the difference was not statistically significant （P〉0.05）. Conclusion The expression level of collagen fibers in patients with ODS is significantly reduced, which may play an important role in the pathogenesis of ODS.