Gastrointestinal manometry has gained wide acceptance in the approach to patients with suspected enteric neuromuscular disorders. However, performing gastrointestinal manometry in these subjects without a previous exhaustive diagnostic evaluation is unjustified. Twelve children (median age: 7.0 years; range: 8 months-13 years), with clinical and x-ray features suggesting chronic intestinal pseudoobstruction, were referred to our unit for gastrointestinal manometry. The latter was performed with a perfused catheter for 5 hr in the fasting state and for 90 min after feeding. Data were compared with those recorded in eight age-matched controls. In all patients and controls, interdigestive motor complexes with propagated phases III were detected; a regular postprandial antroduodenal motor activity was also recorded. Patients and controls did not differ for fed antral and duodenal motility indexes, fed antroduodenal coordination, and length of duodenal phase III. Most of the patients showed short or prolonged bursts of nonpropagated activity in the fasting and/or fed states; in four cases fasting and/or fed sustained phasic activity was recorded. Manometric evidence of migrating motor complexes and postfeeding activity did not support the diagnosis of intestinal pseudoobstruction and suggested redirecting the diagnostic evaluation. Final diagnoses were: Munchausen syndrome-by-proxy (four cases), celiac disease (two cases), intestinal malrotation (two cases), Crohn's disease (two cases), multiple food intolerance (one case), and congenital chloride-losing diarrhea (one case). It is concluded that in children with suspected chronic intestinal pseudoobstruction manometric evidence of migrating motor complexes and fed motor activity excludes an enteric neuromuscular disorder and suggests a reassessment of the diagnostic work-up. Furthermore, if gastrointestinal manometry shows migrating motor complexes and postfeeding motor activity, qualitative abnormalities of the manometric tracings do not indicate an underlying enteric neuromuscular disorder and must not be overemphasized. Patients referred for gastrointestinal manometry should previously undergo an extensive diagnostic investigation to exclude disorders mimicking chronic intestinal pseudoobstruction.