The Diagnostic Value of a Digital Rectal Examination Compared With High-Resolution Anorectal Manometry in Patients With Chronic Constipation and Fecal Incontinence

TLDR

Digital rectal examination (DRE) is a simple clinical method for diagnosing anorectal disorders, while high‑resolution anorectal manometry (HRAM) promises improved accuracy, yet no studies have directly compared the two. This study aimed to evaluate the diagnostic value of DRE versus HRAM in patients with chronic constipation or fecal incontinence. We performed standardized DRE, HRAM, and balloon expulsion tests on 309 consecutive patients, assessing diagnostic yield and agreement, and found HRAM diagnosed dyssynergia in 77.2% of constipated patients. DRE demonstrated 93.2% sensitivity, 58.7% specificity, and 91% positive predictive value for dyssynergia, with moderate agreement (κ = 0.542) with HRAM; in fecal incontinence, agreement was moderate for squeeze pressure (κ = 0.418) but poor for resting tone (κ = 0.079), indicating DRE is a useful bedside screening test for dyssynergia.

Abstract

Digital rectal examination (DRE) is a simple clinical method to diagnose anorectal disorders. High-resolution antorectal manometry (HRAM) based on a spatiotemporal plot is expected to promote improved diagnostic accuracy. However, there are no reports comparing the effectiveness of DRE and HRAM. The aim of our study was therefore to evaluate the diagnostic value of DRE compared with HRAM.A total of 309 consecutive patients with chronic constipation (n=268) or fecal incontinence (n=41) who underwent a standardized DRE, HRAM, and balloon expulsion test were enrolled in this study. The diagnostic yield of DRE compared with HRAM was determined, and agreement between DRE and HRAM data was evaluated.Of the constipated patients, 207 (77.2%) were diagnosed with dyssynergia using HRAM. The sensitivity, specificity, and positive predictive value of DRE in the diagnosis of dyssynergia were 93.2%, 58.7%, and 91.0%, respectively, and moderate agreement was seen between the two modalities (κ-coefficient =0.542, P<0.001). In patients with fecal incontinence, there was moderate agreement in terms of anal squeeze pressure between the two modalities (κ-coefficient =0.418, P=0.006); however, there was poor agreement for anal resting tone (κ-coefficient =0.079, P=0.368).DRE shows high sensitivity and positive predictive value in detecting dyssynergia compared with HRAM, and could therefore be used as a bedside screening test for the diagnosis of this disorder. Further studies are warranted to evaluate the correlation between DRE and HRAM in assessing anal sphincter pressure.