Microdissection Study of the Myentric Plexus in Acardia, Ataxia-telangiectasia, Cystic Fibrosis, Extrahepatic Biliary Atresia, Pediatric Aids and Werdnig-Hoffmann Disease

Microdissection-point count morphometric study of the myenteric (Auerbach) plexus or esophagus, small intestine, and colon was done for infants and children with acardia (2), ataxia-telangiectasia (5), cystic fibrosis of the pancreas (CFP) (25), extrahepatic biliary atresia (EBA) (17), pediatric AIDS (10), and Werdnig-Hoffmann disease (WHD) (8). Values for fractional area of neural tissue in the plane of the plexus were compared to those of control patients in same age range as those in each disease category by t-test. Statistically abnormal values included low values for small intestine and colon in Werdnig-Hoffmann disease, high values for small intestine and colon in biliary atresia, and high value for colon but a low value for small intestine in cystic fibrosis. Values for all three loci were within the normal range for ataxia telangiectasia and pediatric AIDS. The mechanisms of the low value for small and large intestines in WHD, which causes chronic constipation as a result of skeletal muscle weakness, and of the high values for colon in CFP and EBA, both causing malabsorption with bulky stools, are unclear. The value for small intestine in acardia was normal for term but lower than expected for fetal bowel of the same size, possibly because of reduced neural crest inflow to the fetal bowel.