Grossi Ugo, Carrington Emma V, Bharucha Adil E, Horrocks Emma J, Scott S Mark, Knowles Charles H
National Centre for Bowel Research and Surgical Innovation and GI Physiology Unit, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA.
Gut. 2016 Mar;65(3):447-55. doi: 10.1136/gutjnl-2014-308835. Epub 2015 Mar 12.
The diagnostic accuracy of anorectal manometry (AM), which is necessary to diagnose functional defecatory disorders (FDD), is unknown. Using blinded analysis and standardised reporting of diagnostic accuracy, we evaluated whether AM could discriminate between asymptomatic controls and patients with functional constipation (FC).
Derived line plots of anorectal pressure profiles during simulated defecation were independently analysed in random order by three expert observers blinded to health status in 85 women with FC and 85 age-matched asymptomatic healthy volunteers (HV). Using accepted criteria, these pressure profiles were characterised as normal (ie, increased rectal pressure coordinated with anal relaxation) or types I-IV dyssynergia. Interobserver agreement and diagnostic accuracy were determined.
Blinded consensus-based assessment disclosed a normal pattern in 16/170 (9%) of all participants and only 11/85 (13%) HV. The combined frequency of dyssynergic patterns (I-IV) was very similar in FC (80/85 (94%)) and HV (74/85 (87%)). Type I dyssynergia ('paradoxical' contraction) was less prevalent in FC (17/85 (20%) than in HV (31/85 (36.5%), p=0.03). After statistical correction, only type IV dyssynergia was moderately useful for discriminating between FC (39/85 (46%)) and HV (17/85 (20%)) (p=0.001, positive predictive value=70.0%, positive likelihood ratio=2.3). Interobserver agreement was substantial or moderate for identifying a normal pattern, dyssynergia types I and IV, and FDD, and fair for types II and III.
While the interpretation of AM patterns is reproducible, nearly 90% of HV have a pattern that is currently regarded as 'abnormal' by AM. Hence, AM is of limited utility for distinguishing between FC and HV.
肛门直肠测压（AM）对于诊断功能性排便障碍（FDD）是必要的，但其诊断准确性尚不清楚。我们采用盲法分析和标准化的诊断准确性报告，评估AM能否区分无症状对照者和功能性便秘（FC）患者。
对85例FC女性患者和85例年龄匹配的无症状健康志愿者（HV）模拟排便时的肛门直肠压力曲线进行衍生线图分析，由3名对健康状况不知情的专家观察者按随机顺序独立分析。根据公认标准，将这些压力曲线分为正常（即直肠压力升高与肛门松弛协调）或I-IV型排便协同失调。确定观察者间的一致性和诊断准确性。
基于盲法共识的评估显示，所有参与者中有16/170（9%）呈现正常模式，HV中仅11/85（13%）呈现正常模式。FC患者（80/85，94%）和HV（74/85，87%）中排便协同失调模式（I-IV型）的合并频率非常相似。I型排便协同失调（“矛盾”收缩）在FC患者中（17/85，20%）比在HV中（31/85，36.5%）更为少见（p=0.03）。经过统计学校正后，只有IV型排便协同失调对区分FC患者（39/85，46%）和HV（17/85，20%）有一定作用（p=0.001，阳性预测值=70.0%，阳性似然比=2.3）。观察者间在识别正常模式、I型和IV型排便协同失调以及FDD方面的一致性为高度或中度，在识别II型和III型方面的一致性为尚可。
虽然AM模式的解读具有可重复性，但近90%的HV呈现出目前AM认为“异常”的模式。因此，AM在区分FC和HV方面的效用有限。
