title: Chronic abdominal wall pain misdiagnosed as functional abdominal pain.
abstract: BACKGROUND
  The abdominal wall is often neglected as a cause of chronic abdominal pain. The aim of this study was to identify chronic abdominal wall pain syndromes, such as anterior cutaneous nerve entrapment syndrome (ACNES), in a patient population diagnosed with functional abdominal pain, including irritable bowel syndrome, using a validated 18-item questionnaire as an identification tool.
  
  
  METHODS
  In this cross-sectional analysis, 4 Dutch primary care practices employing physicians who were unaware of the existence of ACNES were selected. A total of 535 patients ≥18 years old who were registered with a functional abdominal pain diagnosis were approached when they were symptomatic to complete the questionnaire (maximum 18 points). Responders who scored at least the 10-point cutoff value (sensitivity, 0.94; specificity, 0.92) underwent a diagnostic evaluation to establish their final diagnosis. The main outcome was the presence and prevalence of ACNES in a group of symptomatic patients diagnosed with functional abdominal pain.
  
  
  RESULTS
  Of 535 patients, 304 (57%) responded; 167 subjects (31%) recently reporting symptoms completed the questionnaire. Of 23 patients who scored above the 10-point cutoff value, 18 were available for a diagnostic evaluation. In half of these subjects (n = 9) functional abdominal pain (including IBS) was confirmed. However, the other 9 patients were suffering from abdominal wall pain syndrome, 6 of whom were diagnosed with ACNES (3.6% prevalence rate of symptomatic subjects; 95% confidence interval, 1.7-7.6), whereas the remaining 3 harbored a painful lipoma, an abdominal herniation, and a painful scar.
  
  
  CONCLUSIONS
  A clinically relevant portion of patients previously diagnosed with functional abdominal pain syndrome in a primary care environment suffers from an abdominal wall pain syndrome such as ACNES.
authors.affiliation: the Department of Surgery, Máxima Medical Center, Veldhoven, The Netherlands; and SolviMáx, Center of Excellence for Chronic Abdominal Wall and Groin Pain, Eindhoven, The Netherlands.
authors.forename: Tijmen
authors.initials: T
authors.lastname: van Assen
authors.forename: Jenneke W A J
authors.initials: JW
authors.lastname: de Jager-Kievit
authors.forename: Marc R
authors.initials: MR
authors.lastname: Scheltinga
authors.forename: Rudi M H
authors.initials: RM
authors.lastname: Roumen
mesh_terms: D015746:Abdominal Pain / Q000175:diagnosis* / Q000453:epidemiology; D034861:Abdominal Wall / Q000294:innervation*; D059350:Chronic Pain / Q000175:diagnosis* / Q000453:epidemiology; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000175:diagnosis* / Q000453:epidemiology; D009426:Netherlands / Q000453:epidemiology; D058007:Physicians, Primary Care; D015995:Prevalence; D011795:Surveys and Questionnaires
keywords: Abdominal Pain; Anterior Cutaneous Nerve Entrapment Syndrome; Chronic Pain; Irritable Bowel Syndrome; Prevalence Studies