Comparison of Mucin Patterns in Colonic Pathologies by Histochemistry

[摘要] Introduction: High Iron Diamine Alcian blue(HID-AB) is a well-established technique fordemonstrating colonic acid mucins namelysulphomucins (brown- black) and sialomucins(blue). In certain colonic pathologiesexpression of sulphomucin, the predominantmucin in normal colonic epithelium is altered.Objective: To compare the changes in thepattern of mucin staining in, adenocarcinoma(AC), normal colonic epithelium, solitary rectalulcer (SRU), transitional zone mucosa (TZ)(i.e.: normal non dysplastic mucosa adjacent toadenocarcinoma) and in ulcerative colitis (UC).Method: AC-21, normal colonic epithelium-30,SRU-23, TZ-20, UC-29 biopsies were stainedwith the HID-AB stain. Two investigatorsassessed the percentages of mucin staining bycounting the number of cells staining forsulphomucin and sialomucin in an area ofcolonic epithelium measuring 1mm in length.The differences in these 5 categories wereassessed for statistical significance using theone-way ANOVA test and a Post HocComparison of the mean values was carriedout to establish which groups were different.Results: ACs showed no sulphomucin orsialomucin staining while normal colonicepithelium showed nearly 100% sulphomucinstaining. The percentage mean value for sulphomucinstaining was AC-12.47%, normal colonicepithelium - 96.7%, SRU-35.7%, TZ-48.98%,and UC –75.43%. Hence the differencesbetween these categories reached a level ofstatistical significance except between TZ andSRU.Conclusion: The patterns of mucin stainingobserved with HID/AB staining includedrelatively similar changes in mucin staining inthe TZ and SRU, the loss acid mucin staining inAC and the relatively mild degree ofsulphomucin loss in UC. Though there aresignificant differences in mucin stainingbetween some of these colonic pathologiespractical problems were encountered in usingHID/AB as a diagnostic tool.

[学科分类] 生理学与病理学