THE COLONIC AIR INSUFFLATION TEST INDICATES A COLONIC CAUSE OF ABDOMINAL-PAIN - AN AID IN THE MANAGEMENT OF IRRITABLE-BOWEL-SYNDROME

We evaluated a standardized colonic air insufflation test in patients investigated for abdominal pain; 195 patients were evaluable. Of 164 p atients with functional abdominal pain, 100 of the 128 (78%) with irri table bowel syndrome diagnosed on the basis of two or more Manning cri teria (group A) had positive tests, compared with 19 of the 36 (53%) w ith functional abdominal pain not satisfying the diagnostic criteria f or irritable bowel syndrome (group B). Eight of the 10 patients (80%) with structural colonic disease had positive tests (group C), and 3 of the 21 patients (14%) with structural noncolonic causes of abdominal pain (group D) had positive tests (group A vs. B, A vs. D, and C vs. D , p < 0.01). The air insufflation test had a sensitivity of 78% for th e diagnosis of colonic pain and a specificity of 61%. The positive pre dictive value was 83% and the negative predictive value 54%. Sequentia l tests by two independent observers on 26 consecutive patients showed no interobserver variation. The colonic air insufflation test warrant s further evaluation as an adjunct to the Manning criteria in the diag nosis of irritable bowel syndrome. It can also serve as an investigati ve tool to define a subset of patients with functional abdominal pain who do not fulfill the current criteria for irritable bowel syndrome y et whose pain actually originates from the colon.