Pathology of neuromuscular disorders of the small intestine and colon

Enteric Nervous System: Neuropathic Gastrointestinal Motility

“…The idiopathic form of inflammatory degenerative ENS neuropathy is unrelated to neoplasms, infectious conditions, or other known diseases [61][62][63][64][65][66]. On the other hand, the varicella-zoster virus (i.e., chickenpox) establishes latency in ENS neurons and can reactivate to lyse and kill the neurons within 48 h of infection [54,55,[67][68][69].…”

Chronic intestinal pseudo-obstruction

“…Inflammatory neuropathies are characterized by a dense inflammatory infiltrate characterized by CD3 positive (composed of both CD4 and CD8) lymphocytes almost invariably confined to the myenteric plexus (hence the term of lymphocytic myenteric ganglionitis) [7][8][9]19] . The close apposition of CD3 lymphocytes to myenteric neurons provides the basis to neuro-immune interactions targeting and affecting ganglion cell structure and survival [20,21] . Indeed, experimental evidence indicates that inflammation/immune activation in the gastrointestinal tract can profoundly affect both morphology and function of the enteric nervous system (ENS).…”

Phenotypic expansion of visceral myopathy associated with ACTG2 tandem base substitution

“…[1][2][3] The first genes associated with smooth muscle myopathy were MYH11 and ACTA2, both of which encode components of the contractile sarcomere, in families with thoracic aortic dissections (TAADs; MIM: 132900 and 611788). 4,5 Later, variants in ACTA2 were shown to be associated with multisystemic smooth muscle dysfunction syndrome (MIM: 613834) and a broad phenotypic spectrum.…”

“…14,16 Because of the variable symptomatology, this group of visceral myopathies constitutes a diagnostic challenge and some adult patients are referred to as chronic pseudo-obstruction, hollow visceral myopathy or pseudoHirschprung disease. 2,17 The findings on pathogenic MYH11 and ACTA2 variants in TAAD have raised the possibility that different components of the smooth muscle contractile unit and cytoskeleton may be responsible for other types of myopathies. Indeed, a recent study on a Finnish family segregating autosomal dominant familial visceral myopathy (FVM) with severe abdominal symptoms revealed segregation of a c.422C4A…”