Clinical study on the expression of PGP 9.5 and S-100 protein in the rectal end with congenital anorectal malformations

Objective To study the enteric nervous system (ENS) in the rectal end with clinical different types of anorectal malformations (ARMs) and explore the possible pathological mechanisms of postoperative defecation disorders. Methods 76 cases of rectal end samples came from the patients with ARMs from January 2001 to December 2005, of which hightype was in 11 cases, intermediate-type in 26 cases, and lowtype in 39 cases. The mean fetal age, birth weight and the age acquiring the rectal samples were analyzed and the expression of PGP 9.5 and S- 100 protein in above samples were visualized by immunohistochemistry. Results There were no significant differences in the mean fetal age and birth weight among the different types of ARMs (P 0.05). The expression of PGP 9.5 and S- 100 protein in the high- type anomalies was obviously lower than that in the intermediate- (high- type vs intermediate- type, PGP9.5: 0.422±0.008 vs 0.447±0.006, P = 0.0226; S- 100: 0.417±0.009 vs 0.442±0.007, P=0.0401) and low- type anomalies (high- type vs low- type, PGP9.5: 0.422±0.008 vs 0.450±0.009, P = 0.0331; S- 100: 0.417±0.009 vs 0.447±0.010, P = 0.0436), but there were no marked differences between the intermediate- and lowtype anomalies (P 0.05). The expression of PGP 9.5 and S-100 protein in the onestage procedure group of the intermediate-type anomalies was obviously lower than that in the staged-procedure group (PGP 9.5: 0.421±0.010 vs 0.453±0.006, P = 0.0128; S- 100: 0.413±0.010 vs 0.449±0.006, P = 0.0048). There was a significant difference in the age acquiring the rectal samples between the male group and the female group of the low- type anomalies (0.11±0.08 months vs 6.15±0.29 months, P 0.0001), but there were no statistical differences in the expression of PGP 9.5 and S- 100 protein among the male group and the female group (P 0.05). Conclusions There is a close relation between the developmental extent of the ENS and the abnormal position of the ARMs, which may be one of the pathological mechanisms of postoperative defecation disorders in the hightype anomalies. The development of the ENS in the rectal end with intermediate- type anomalies may gradually growmature with the age.