Correlation between anorectal manometric findings and clincal outcome in patients operated for hirschsprung's disease

ABSTRACT

In order to identify a possible correlation between anorectal manometry [ARM] findings and clinical outcome in patients operated for Hirschsprung's disease [HD], ARM was performed on 58 patients 4-9 years after operation. In relation to bowel habits, three different clinical categories were defined. Normal bowel movement was present in 39 [67%] patients [Group I]. Fourteen [24%] patients had frequent soiling and were considered incontinent [Group II]. The remaining five [8.6%] cases had constipation [Group III]. ARM in group I revealed normal tone [10-40 mm Hg] in 21 [53.8%] and increased tone [>40 mm Hg] in the remaining 18 patients. Seven out of 14 [50%] of group II patients had markedly decreased anal tone [<10 mm Hg], while all five patients with constipation had increased tone. The mean anal sphincter tone in group II was significantly lower than that of groups I and III [p < 0.05]. Furthermore, while rectoanal reflex [RAR] was present in about one third of patients in group I, it was absent in patients of group III. This reflex, however, could not be evaluated because of the very low tone in the soiling group. In conclusion, the majority of patients with HD had normal bowel movement after surgery along with normal or increased internal sphincter tone. Although most of these patients showed lack of relaxation, which has no diagnostic value, the presence of RAR may have a predictive value, since it is frequently associated with fecal continence. Moreover, although high tonicity was not correlated with clinical status, markedly decreased anal tone was almost always associated with incontinence. Therefore, to make a proper decision for further management, the clinical status of the patient's bowel habit should be interpreted in the light of ARM findings: