Acquired isolated hypoganglionosis as a distinct entity: results from a nationwide survey.

Acquired isolated hypoganglionosis (A-IH) is a late-onset intestinal pseudo-obstruction disorder and shows different pathophysiological findings from congenital isolated hypoganglionosis (C-IH). In this study, we retrospectively examined five cases of A-IH and investigated the features of A-IH. Five cases of A-IH were extracted from a nationwide retrospective cohort study in 10 years, from which totally 355 cases of Allied Disorders of Hirschsprung's Disease (ADHD) were collected. Ages of onset were between 13 and 17 years in three cases, and 4 years and 4 months in ones. Initial symptoms were abdominal distension and/or chronic constipation in 4 cases, whereas one exhibited intestinal perforation. Affected lesions varied from case to case, extending various length of intestinal tracts. All cases underwent multiple operations (average: 4.6 times), such as enterostomy, resection of dilated intestines, and/or pull-through. Pathological findings showed the decreased numbers of ganglion cells and degeneration of ganglion cells, whereas the size of the plexus was normal. Currently, all cases were alive and almost all eat regular food without requiring parenteral feeding. A-IH is rare, but distinct entity characterized by different clinical courses and pathological findings from those of C-IH. The outcome is considered to be favorable after a resection of affected intestine.