Routine botulinum toxin injection one month after a Swenson pull-through does not change the incidence of Hirschsprung associated enterocolitis

Patients with Hirschsprung disease (HD) are at risk of Hirschsprung associated enterocolitis (HAEC) following pull-through. The purpose of this study was to determine if routine Botulinum toxin (BT) injected one-month post pull-through decreases the incidence of HAEC.We reviewed patients who underwent a primary (not redo) pull-through operation for HD between April 2014 to December 2019. Over the most recent 18 months, BT was administered routinely one-month post-pull-through procedure; these patients were compared to the prior group that did not receive routine BT. A HAEC episode was defined as one that required initiation of treatment for obstructive symptoms in the inpatient or outpatient setting with antibiotics and irrigations. Categorical variables were compared using the nonparametric chi-square test or Fisher's exact test. Continuous variables were compared using the two-tailed Student's t-test. P-value0.05 was determined to be statistically significant.A total of 70 patients underwent Swenson pull-through during the study period (52% male). There were no statistically significant differences in demographics in the BT vs. non-BT group. Routine post-pull-through BT was given in 28 patients and did not significantly change HAEC incidence compared to the non-BT group (12/28, 43% vs. 16/42, 38%. P = 0.691). Of note, the BT group patients developed HAEC significantly sooner than the patients in the non-BT group (37.5 days vs. 253 days, p = 0.029). More patients in the BT group (n = 18, 64%) required at least one subsequent BT injection compared to the patients in the non-BT group (n = 11, 26%. P = 0.001).We conclude that routine postoperative botulinum toxin injection given one month postoperatively from Swenson pull-through did not change the incidence of HAEC. A prospective controlled study is necessary to confirm these findings.