Colonoscopic characteristics of infants with allergic-eosinophilic proctocolitis

Background: Rectal bleeding is an alarming symptom and requires additional investigations. Hematochezia in infancy has been explained mainly by allergic colitis since usually these patients are otherwise asymptomatic.

Aim: The objectives of this study were to evaluate prospectively the clinical course in breast-fed infants of rectal bleeding and evaluate basic laboratory findings, macroscopic and microscopic abnormality found in colonoscopy.

Patients: This study prospectively evaluated 44 consecutive breast-fed infants who presented with fresh blood mixed with stools. None had evidence of a bleeding diathesis, bacterial enteritis or fissures. Elimination diet (cow's milk, eggs, soya, nuts) was offered to the mothers for average 6 weeks. Only 16 patients were showing hematochezia thereafter. Written consent for colonoscopy and biopsy was obtained of this 16 infants (mean age, 4,6 months, range, 25 days-7 months, 9 girls).

Results: Nine out of 16 patients had allergic colitis and 7/16 had eosinophilic colitis. Eosinophilic colitis (EC) was characterized histologically by >20 eosinophils per high-power field (HPF) and allergic colitis (AC) was diagnosed by means of eosinophils between 6–20 cells per HPF. Control biopsies showed only 1,48+/-0,78 eosinophils per HPF. AC and EC patients exhibited slight sideropenic anemia, however, blood eosinophils were not elevated in AC nor in EC patients (AC, 3,66+/-0,78, EC, 3,25+/-1,25, controls, 4,95+/-1,87%). Colonoscopy revealed lymphonodular hyperplasia more often in AC (87,5%) than in EC (50%), in contrary, aphthous ulcerations were more common in EC (75%) than in AC (50%), nevertheless, the discrepancies failed to reach significance.

Summary: AC and EC are very common in otherwise asymptomatic breast-fed infants with normal fecal culture or other obvious diseases after long-lasting hematochezia. There was no difference between AC and EC concerning laboratory data, however, lymphonodular hyperplasia was more often in AC, and aphthous ulcerations were more common in EC patients at colonoscopy.