504 Golden-Finger: Digital Rectal Exam Predicts Dyssynergic Defecation but Not Type of Dyssynergy Pattern on ARM

Abstract

INTRODUCTION: Functional defecation disorders are a common cause of chronic constipation and the diagnosis include an abnormality in two or more of the following tests: balloon expulsion test (BET), anorectal manometry (ARM) or uncoordinated defecation on electromyography. Additionally, there have been four types of anorectal manometry dyssynergy patterns identified. Rao et al have shown that digital rectal examination (DRE) performed by a single expert gastroenterologist can accurately detect patients with dyssynergia. We conducted a study evaluating whether DRE performed by gastroenterology specialists could predict the presence and type of dyssynergia in patients with chronic constipation. METHODS: Patients with chronic constipation as defined by Rome IV criteria were evaluated by GI specialty providers at a single tertiary care hospital. After performing a DRE, each provider documented a prediction regarding the type of dyssynergy pattern that would be identified on ARM as well as whether the patient would pass the balloon during BET. An abnormal BET was defined as failure to pass the balloon in less than 60 seconds. Patients subsequently underwent ARM and BET and results of predicted and measured values on ARM and BET were compared. RESULTS: 21 patients were referred to undergo ARM and BET. 19 patients met the inclusion criteria. 16 displayed a dyssynergy pattern on ARM. Of the 16 patients, 11 were also identified to have features of dyssynergia on DRE with a detection rate of 69% (Table 1). One patient was noted to have features of dyssynergia on DRE but had normal ARM. Two patients had normal DRE with normal ARM. 11 of the 16 patients with dyssynergia on ARM had abnormal BET. Of the 11 patients with abnormal BET, 7 were predicted to have abnormal BET based on DRE (64% detection rate). DRE predicted the correct type of dyssynergia (type 1-4) in 31% of patients (Table 2). CONCLUSION: Studies have shown that DRE can predict dyssynergia when performed by a single expert gastroenterologist with a detection rate of 73%. Our analysis suggests that DRE can be used to predict dyssynergia on ARM and outcomes of BET even when multiple providers perform the exam. However, DRE is not a good predictor of the type of dyssynergia. Further studies are needed to evaluate the differences in detection rates between types of dyssynergia classified by ARM, and to assess whether there is a difference in detection rates between trainees and attendings.