<prompt> Achalasia cardia due to:Degeneration of myenteric plexus due to toxinDegeneration and absence of ganglion cells in auerbach PlexusExcess of Ganglion cells in auerbach PlexusDegeneration of meissners Plexus  <response>: Ans. b Degeneration and absence of ganglion cells in auerbach plexusRef: Bailey and Love 26th edition, Page 1014 Achalasia cardia is due to loss of ganglion cells in myenteric plexus. Histology shows loss of inhibitory neurons with a variable degree of chronic inflammation.Important point of difference from Hirschsprung disease: Dilated segment of Achalasia shows such loss of ganglion cells, whereas dilated Colon in Hirschsprung disease shows normal ganglion cells in dilated part. 