New pathogenetic aspects of gut dysmotility in aplastic and hypoplastic desmosis of early childhood

The peristaltic movement of the gut is a function of the alternating contra ction and relaxation of circular and longitudinal muscles. This movement is induced by a tendon-like connective-tissue net (TCTN) in the circular and longitudinal muscles, which are both rooted in a connective-tissue plexus l ayer (CTPL). In children with a therapy-resistant aperistaltic or hypoperis taltic syndrome who had normally-developed enteric innervation, a lack of t he TCTN in the muscularis propria was observed. Over the last 2 years, 241 children with chronic constipation were investigated histopathologically; 4 6 children surgically treated by partial resection of the gut or diagnostic ally investigated by whole-mount biopsy. Fifteen children had a hypoperista lsis syndrome and 3 had an aperistalsis syndrome. All specimens were native and cut in a cryostat. Enteric innervation was examined by acetylcholinest erase and dehydrogenase reactions. The TCTN in the muscularis propria was s tained with picric acid/sirius red. In the children with an aperistalsis sy ndrome, a complete lack of the TCTN in circular and longitudinal muscles wa s observed. A CTPL was not developed. The children with a hypoperistalsis s yndrome had no CTPL, but had a partly-developed TCTN in the circular and lo ngitudinal muscles, which gradually faded in the direction of the plexus la yer. Independent of a well-developed enteric nervous system, a lack of the TCTN in longitudinal and circular muscles and a missing CTPL (aplastic desm osis) abolishes the coordinated peristaltic movement of the gut. An isolate d lack of the CTPL in the myenteric plexus (hypoplastic desmosis) results i n a hypoperistalsis syndrome. An anomaly of the TCTN in the muscularis prop ria disturbs gut-muscle mechanics, and is another cause of gut dysmotility.