Between January and July 2018, 26 children were consecutively referred to our outpatient pediatric gastroenterology clinic having previously been diagnosed with IBS, allegedly according to Rome IV criteria: 10 IBS-D and 16 IBS-M
. Diagnostic criteria for IBS subtypes were, in brief, the following [
8]: IBS-D, that is with predominant diarrhea, more than one-fourth (25%) of bowel movements with Bristol stool form types 6 or 7 and less than one fourth (25%) of bowel movements with Bristol stool form types 1 or 2; IBS-M, that is with mixed bowel habits, more than one-fourth (25%) of bowel movements with Bristol stool form types 1 or 2 and more than one fourth (25%) of bowel movements with Bristol stool form types 6 or 7; IBS-C, that is with predominant constipation, more than one-fourth (25%) of bowel movements with Bristol stool form types 1 or 2 and less than one fourth (25%) of bowel movements with Bristol stool form types 6 or 7. These patients had previously undergone, in other hospitals, a diagnostic work-up that ruled out organic causes such as celiac disease, inflammatory bowel disease and surgically-treatable abdominal conditions. After approval of the ethics committee of the University of Messina Hospital “Policlinico G. Martino” and parents’ verbal informed consent, we enrolled the children in a 2-month prospective study aimed at verifying the hypothesis that they had occult constipation only. For the purpose of this investigation, we chose to define occult constipation when at least one of the following elements was present: 1) a history of FC in the first 3 years of life, 2) palpable fecal masses on physical exam, 3) soiling without other Rome IV criteria of FC, 4) excessive fecal load on plain abdominal radiograph performed if excessive fecal burden was suspected in patients whose physical examination was unreliable/not possible [
2]. Our diagnostic work-up simply included IgA anti-tissue transglutaminase antibodies (tTG-IgA) in all the patients with IBS-D and IBS-M, due to the presence of diarrhea, in order to rule out celiac disease. The patients with normal tTG-IgA who fulfilled these criteria were treated for fecal impaction according to evidence-based recommendations [
9], starting with a dose of polyethylene glycol (1–1.5 g/Kg per day for 3–6 days) followed by a maintenance dose. At 2 months they were re-evaluated. A group of 16 IBS-C, for whom a treatment for constipation is recommended by Roma IV criteria, were consecutively seen in the same period at the outpatient clinic, considered as control and evaluated after 2 months of treatment. The endpoints at this time were: a decrease of more than 50% of abdominal pain intensity and frequency scores [
8] for all, and disappearance of diarrhea as result of treating constipation. Pain intensity was scored using the validated 6-face Faces Pain Scale Revised intensity score [
10], while pain frequency was scored, according to Korterink et al. [
11] as follows: 0 ¼ no daily pain, 1 ¼ 0–20 min of daily pain, 2 ¼ 20–40 min of daily pain, 3 ¼ 40–90 min of daily pain, and 4 ¼ > 90 min of daily pain. At the 2-month control, the maintenance dose was confirmed but it was allowed to stop or to decrease it at choice of the patients, parents and family pediatricians. A follow-up was planned at least 6 months for evaluating the duration of treatment and the outcome with and without treatment.
We analyzed the costs for investigation and treatment sustained by the families in the last year before referral to our Unit by recording them through a structured questionnaire. These estimates were then compared with the costs of our diagnostic work-up.