The international anorectal physiology working group (IAPWG) recommendations: Standardized testing protocol and the London classification for disorders of anorectal function

Emma V. Carrington, Henriette Heinrich, Charles H. Knowles, Mark Fox, Satish Rao, Donato F. Altomare, Adil E. Bharucha, Rebecca Burgell, William D. Chey, Guiseppe Chiarioni, Philip Dinning, Anton Emmanuel, Ridzuan Farouk, Richelle J. F. Felt-Bersma, Kee Wook Jung, Anthony Lembo, Allison Malcolm, Ravinder K. Mittal, Franҫois Mion, Seung-Jae MyungP. Ronan O’Connell, Christian Pehl, Jose María Remes Troche, R. Matthew Reveille, Carolynne J. Vaizey, Veronique Vitton, William E. Whitehead, Reuben K. Wong, S. Mark Scott, All members of the International Anorectal Physiology Working Group

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Background: This manuscript summarizes consensus reached by the International Anorectal Physiology Working Group (IAPWG) for the performance, terminology used, and interpretation of anorectal function testing including anorectal manometry (focused on high-resolution manometry), the rectal sensory test, and the balloon expulsion test. Based on these measurements, a classification system for disorders of anorectal function is proposed. Methods: Twenty-nine working group members (clinicians/academics in the field of gastroenterology, coloproctology, and gastrointestinal physiology) were invited to six face-to-face and three remote meetings to derive consensus between 2014 and 2018. Key recommendations: The IAPWG protocol for the performance of anorectal function testing recommends a standardized sequence of maneuvers to test rectoanal reflexes, anal tone and contractility, rectoanal coordination, and rectal sensation. Major findings not seen in healthy controls defined by the classification are as follows: rectoanal areflexia, anal hypotension and hypocontractility, rectal hyposensitivity, and hypersensitivity. Minor and inconclusive findings that can be present in health and require additional information prior to diagnosis include anal hypertension and dyssynergia. Conclusions and Inferences: This framework introduces the IAPWG protocol and the London classification for disorders of anorectal function based on objective physiological measurement. The use of a common language to describe results of diagnostic tests, standard operating procedures, and a consensus classification system is designed to bring much-needed standardization to these techniques.
Original languageEnglish
Article numbere13679
JournalNeurogastroenterology and Motility
Issue number1
Publication statusPublished - 1 Jan 2020
Externally publishedYes

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