Neurogastroenterology Unit, University of Manchester, Manchester, UK.
Gastroenterology. 2013 Oct;145(4):749-57; quiz e13-4. doi: 10.1053/j.gastro.2013.07.014. Epub 2013 Jul 19.
BACKGROUND & AIMS: Patients with irritable bowel syndrome with constipation (IBS-C) and patients with functional constipation (FC) have similar symptoms, and these disorders overlap in their diagnostic features. Little is known about their overlap in physiology or the involvement of serotonin signaling. We investigated relationships between platelet-depleted plasma concentrations of serotonin, gastrointestinal symptoms, and motor-sensory function in patients with FC or IBS-C compared with healthy volunteers (controls).
We measured platelet-depleted plasma concentrations of serotonin in fasting and fed individuals with IBS-C (n = 23; 19-50 years old), FC (n = 11; 25-46 years old), and controls (n = 23; 20-49 years old) recruited in Manchester, UK. We also quantified abdominal and bowel-related symptoms, rectal sensitivity, oro-cecal transit, and colonic (whole intestine) transit.
Patients with IBS-C or FC had similar baseline symptoms, bowel habits, oro-cecal and colonic transit, and fasting concentrations of serotonin and response to meal ingestion. Only patients with IBS-C had increased symptoms after ingestion of a meal (P < .001)-these patients tended to have lower sensory thresholds than patients with FC. Defecation frequency in the combined group of patients with IBS-C or FC correlated inversely with serotonin concentration (r = -0.4; P = .03). Serotonin concentration also correlated with pain threshold (r = 0.4; P = .02) and stool threshold (r = 0.5; P = .06), which correlated inversely with defecation frequency (r = -0.3; P = .10).
FC and IBS-C, based on Rome III criteria, are not distinct disorders, symptomatically or physiologically. Instead, they appear to lie in a spectrum of visceral sensitivity modulated by serotonin signaling. Symptom response to meal ingestion should be considered in patient classification.
便秘型肠易激综合征（IBS-C）患者和功能性便秘（FC）患者具有相似的症状，这些疾病在诊断特征上存在重叠。目前对于它们在生理学上的重叠或血清素信号的参与知之甚少。我们研究了与健康志愿者（对照组）相比，FC 或 IBS-C 患者血小板减少的血浆中血清素浓度与胃肠道症状和运动感觉功能之间的关系。
我们测量了空腹和进食时 IBS-C（n=23；19-50 岁）、FC（n=11；25-46 岁）和英国曼彻斯特招募的对照组（n=23；20-49 岁）患者血小板减少的血浆中血清素浓度。我们还量化了腹部和肠道相关症状、直肠敏感性、口-盲肠传输和结肠（整个肠道）传输。
IBS-C 或 FC 患者的基线症状、排便习惯、口-盲肠和结肠传输以及空腹时的血清素浓度和对进餐的反应相似。只有 IBS-C 患者在进食后出现症状增加（P<0.001）-这些患者的感觉阈值往往低于 FC 患者。IBS-C 或 FC 患者的联合组的排便频率与血清素浓度呈负相关（r=-0.4；P=0.03）。血清素浓度与疼痛阈值（r=0.4；P=0.02）和粪便阈值（r=0.5；P=0.06）也呈正相关，与排便频率呈负相关（r=-0.3；P=0.10）。
根据罗马 III 标准，FC 和 IBS-C 不是不同的疾病，无论是在症状上还是在生理学上。相反，它们似乎位于由血清素信号调节的内脏敏感性谱中。对进餐引起的症状反应应在患者分类中考虑。
