Occult constipation masking as irritable bowel syndrome with predominant diarrhea in Bangladeshi children

Abstract

BACKGROUND

Occult constipation (OC) is defined by the absence of classical symptoms of constipation on initial clinical history, despite objective evidence of fecal retention, such as the presence of hard stool on digital rectal examination or fecal impaction identified on plain abdominal radiography. It is frequently undiagnosed in children and presents with a diverse array of symptoms, such as abdominal pain and frequent defecation with mucoid feces. These symptoms are strikingly similar to irritable bowel syndrome (IBS) with diarrhea (IBS-D).

AIM

To verify the hypothesis that OC may present with the features of IBS-D.

METHODS

This is a prospective observational study that involves consecutive children who were referred to our center as primarily diagnosed with IBS-D (consistent with Rome IV criteria) by another physician and did not improve after at least three months of treatment. Patients presenting with red-flag symptoms suggestive of organic disease were excluded from the study. Patients who exhibited fecal impaction on a plain abdominal radiograph were diagnosed as OC and were administered magnesium hydroxide (milk of magnesia; 400 mg/5 mL) for a period of two months, with a progressive taper over the course of one month. Outcomes were assessed based on changes in pain intensity, frequency, and stool characteristics after the commencement of treatment.

RESULTS

This study included 54 patients who were diagnosed with IBS-D by other consultants and were unresponsive to treatment. Of these patients, 49 (91%) had OC mimicking IBS-D. After commencing treatment for OC, 46 (94%) of the 49 patients demonstrated a positive clinical response (44 good, 2 satisfactory).

CONCLUSION

Children presenting with IBS-D related symptoms who are unresponsive to standard therapy may benefit from evaluation for OC before considering escalation to more invasive investigations.

Keywords: Irritable bowel syndrome; Functional gastrointestinal disorders; Abdominal pain; Diarrhea; Occult constipation

Core Tip: Occult constipation (OC) is a significant diagnostic challenge because its symptoms, such as abdominal pain and frequent mucoid stools, often mimic those of irritable bowel syndrome with diarrhea. This clinical overlap frequently leads to misdiagnosis, where patients receive treatments that inadvertently worsen the underlying fecal impaction. Utilizing a plain abdominal X-ray serves as a practical and effective tool to visualize fecal loading and confirm the diagnosis of OC.