A total of 583 patients were identified in the 4 selected primary care practices as dictated by the 3 ICPC codes of interest. After exclusion based on age <18 years (n = 6), comorbidity (n = 13), other known gastrointestinal disease (n = 8), absence of complaints (n = 2) and personal reasons (n = 19), 535 patients were eligible for screening. Some 369 patients were registered with ICPC code D93 (IBS). The remaining subjects (n = 166) were diagnosed with generalized or localized abdominal pain (codes D01 and D06).
The response rate was 57% (n = 304). Of this responding population, we analyzed the questionnaires of 167 subjects signing informed consent (68% women, age 54 ± 17 years). The remaining 137 subjects did not participate in screening (no complaints at present, n = 94; personal reason, n = 37; missing items in the 18-pAQ, n = 6).
Of these 167 patients, 23 scored ≥10 points on the 18-pAQ. After being contacted, 18 individuals were willing to undergo history taking and physical examination. Nine subjects were found to have IBS, generalized abdominal pain/cramps, or other localized abdominal pain, as diagnosed previously. The other half of this group (n = 9) was diagnosed with a CAWP syndrome, 6 of whom had ACNES (code D93, n = 4; code D01, n = 2). The remaining 3 patients were diagnosed with a painful lipoma (n = 1), an abdominal wall herniation (n = 1), and scar tissue pain (n = 1) based on physical examination and ultrasound investigation (Figure 4).
Flow chart of the study protocol. ACNES, anterior cutaneous nerve entrapment syndrome; CAWP, chronic abdominal wall pain; GI, gastrointestinal.
Of the 6 identified patients with ACNES, 4 received a subfascial trigger point injection using 1% lidocaine, 3 of whom experienced a long-lasting and satisfactory reduction in pain (>3 months). The fourth patient with ACNES received additional manual therapy because the pain was refractory to injections. A neurectomy will be considered if she remains unresponsive.[14,20] Pain levels of patients 5 and 6 were mild. These 2 individuals were reassured once the origin of the pain was explained. Despite the somewhat smaller sample size than calculated in the power analysis, the prevalence of ACNES within the symptomatic functional abdominal pain population in these 4 selected primary care practices was calculated to be 3.6% (95% confidence interval [CI], 1.7–7.6).
J Am Board Fam Med. 2013;26(6):738-744. © 2013 American Board of Family Medicine