Differential expression and clinical significance of calretinin in total colonic aganglionosis

Objective To evaluate the differential calretinin immunostaining in different segments of total colonic aganglionosis and its utility in the diagnosis. Methods Nine specimens including ileum and colon segments were obtained from 9 patients with total colonic aganglionosis (TCA), from 2010 to 2016 year, in Wuhan Children′s Hospital, Tongji Medical College, Huazhong University of Science and Technology. Another 9 ganglionic specimens including the same segments from patients with non-Hirschsprung disease (non-HD) patients were collected as control. All cases were immunostained with calretinin. The patterns of calretinin immunostaining were observed, and morphometric analysis of each sample was performed by image analysis program (Image-Pro-Plus). The mean absorbance was evaluated by calculating the areas of the lamina propria occupied by the positively stained area of the calretinin at high power field. Results The same pattern of calretinin immunostaining was seen in ganglionic ileum and ganglionic colon segments, with staining seen in intrinsic nerves fibers (INF), and in granular aggregates in the lamina propria and muscularis mucosae. There was no significant difference in the numbers of calretinin-positive INF from the ganglionic segments. In contrast, the number of calretinin-positive INF and granular aggregates in aganglionic segments were significantly lower than those in the ganglionic group (P<0.01). In the ileum transitional zone, scattered calretinin staining was observed, and the amount of calretinin-positive INF was significantly lower than those in the proximal segment of ganlionic ileum (P<0.01). Conclusions Since there is significant different expression of calretinin among the different segments from TCA, calretinin immunostaining has potential value in detecting TCA. It could be an important adjunctive method in detecting TCA in the future. Key words: Intestinal diseases; Hirschsprung disease; Immunohistochemistry; Calretinin