Intestinal alkaline phosphatase in the colonic mucosa of children with inflammatory bowel disease

AIM:To investigate intestinal alkaline phosphatase(iAP) in the intestinal mucosa of children with inflammatory bowel disease(IBD).METHODS:Colonic biopsy samples were taken from 15 newly diagnosed IBD patients and from 10 healthy controls.In IBD patients,specimens were obtainedboth from inflamed and non-inflamed areas.The iAP mRNA and protein expression was determined by reverse transcription-polymerase chain reaction and Western blotting analysis,respectively.Tissue localization of iAP and Toll-like receptor(TLR) 4 was investigated by immunofluorescent staining.RESULTS:The iAP protein level in the inflamed mucosa of children with Crohn's disease(CD) and ulcerative colitis(UC) was significantly decreased when compared with controls(both P < 0.05).Similarly,we found a significantly decreased level of iAP protein in the inflamed mucosa in CD compared with non-inflamed mucosa in CD(P < 0.05).In addition,the iAP protein level in inflamed colonic mucosa in patients with UC was decreased compared with non-inflamed mucosa in patients with CD(P < 0.05).iAP protein levels in the non-inflamed mucosa of patients with CD were similar to controls.iAP mRNA expression in inflamed colonic mucosa of children with CD and UC was not significantly different from that in non-inflamed colonic mucosa with CD.Expression of iAP mRNA in patients with noninflamed mucosa and in controls were similar.Co-localization of iAP with TLR4 showed intense staining with a dotted-like pattern.iAP was present in the inflamed and non-inflamed mucosa of patients with CD,UC,and in control biopsy specimens,irrespective of whether it was present in the terminal ileum or in the colon.However,the fluorescent signal of TLR4 was more pronounced in the colon compared with the terminal ileum in all groups studied.CONCLUSION:Lower than normal iAP protein levels in inflamed mucosa of IBD patients may indicate a role for iAP in inflammatory lesions in IBD.Based on our results,administration of exogenous iAP enzyme to patients with the active form of IBD may be a therapeutic option.

Characteristics of allergic colitis in breast-fed infants in the absence of cow's milk allergy

AIM: To investigate the characteristics of mucosal le-sions and their relation to laboratory data and long-term follow up in breast-fed infants with allergic colitis. METHODS: In this study 31 breast-fed infants were prospectively evaluated (mean age, 17.4 wk) whose rectal bleeding had not ceased after a maternal elimi-nation diet for cow's milk. Thirty-four age-matched and breast-fed infants (mean age, 16.9 wk) with no rectal bleeding were enrolled for laboratory testing as con-trols. Laboratory findings, colonoscopic and histological characteristics were prospectively evaluated in infants with rectal bleeding. Long-term follow-up with differ-ent nutritional regimes (L-amino-acid based formula or breastfeeding) was also included. RESULTS: Iron deficiency, peripheral eosinophilia andthrombocytosis were significantly higher in patients with allergic colitis in comparison to controls (8.4±3.2 μmol/L vs 13.7±4.7 μmol/L, P<0.001; 0.67±0.49 G/L vs 0.33±0.17 G/L, P<0.001; 474±123 G/L vs 376±89 G/L, P<0.001, respectively). At colonosco-py, lymphonodular hyperplasia or aphthous ulceration were present in 83% of patients. Twenty-two patients were given L-amino acid-based formula and 8 contin-ued the previous feeding. Time to cessation of rectal bleeding was shorter in the special formula feeding group (mean, 1.4 wk; range, 0.5-3 wk) when com-pared with the breast-feeding group (mean, 5.3 wk; range, 2-9 wk). Nevertheless, none of the patients ex-hibited rectal bleeding at the 3-mo visit irrespective of the type of feeding. Peripheral eosinophilia and cessa-tion of rectal bleeding after administration of elemental formula correlated with a higher density of mucosal eosinophils. CONCLUSION: Infant hematochezia, after cow's milk allergy exclusion, is generally a benign and probably self-limiting disorder despite marked mucosal abnor-mality. Formula feeding results in shorter time to cessa-tion of rectal bleeding; however, breast-feeding should not be discouraged in long-lasting hematochezia.