Decreased density of ganglia and neurons in the myenteric plexus of familial dysautonomia patients

Abstract Background : Familial dysautonomia (FD) is a hereditary disease of the autonomic and sensory nervous system. A prominent manifestation of FD is gastrointestinal dyscoordination, which contributes to the morbidity and mortality in FD. Aim : As the myenteric plexus is an essential factor in gastrointestinal motility control, we compared its morphology in appendices of FD patients and controls. Methods : Appendices from FD patients ( N =19) were obtained during surgery of fundoplication and gastrostomy; normal appendices ( N =17) were obtained from patients suspected to suffer from acute appendicitis, in whom, however, the appendix was found to be normal. Specimens were stained histochemically for NADPH diaphorase (NADPH-d) and in a blinded manner examined under a light microscope for seven morphologic parameters: ganglionic density, neuronal density, ganglionic area, number of stained neurons per ganglion, nerve bundle width, ratio between nervous tissue area and total area, and neuronal area. Results : Ganglionic density was 10.13 per mm 2 in controls versus 5.01 per mm 2 in FD ( p 2 in controls, compared with 22.09 per mm 2 in FD ( p Conclusion : Densities of myenteric ganglia and neurons of FD patients were significantly lower than in controls. This deficiency may contribute to the pathogenesis of FD gastroenteropathy.