* * *megacolon in a section of the colon due to congenital absence of intrinsic ganglion cells in the myenteric and submucosal plexuses of the next distal segment; the aganglionic part is abnormally narrow, and its loss of motor function causes massive hypertrophic dilatation of more proximal segments. The condition appears soon after birth, is more common in males, and causes extreme constipation, abdominal distention, and sometimes vomiting; when severe, it may result in growth retardation. It is sometimes divided into short-segment and long-segment forms, may occur as an isolated trait or in conjunction with other congenital anomalies, and may show dominant, recessive, or multigenic patterns of inheritance, with gender-dependent penetrance. It has been associated with mutations in one or a combination of several genes, including genes encoding either a protein-tyrosine kinase receptor (RET) or one of its ligands, and genes encoding either endothelin-3 (EDN3) or its receptor (EDNRB). Called also Hirschsprung disease, aganglionic m., and pelvirectal achalasia.
Congenital megacolon; lateral view of barium enema in a three-year-old girl.
Medical dictionary. 2011.
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congenital megacolon — noun congenital condition in which the colon does not have the normal network of nerves; there is little urge to defecate so the feces accumulate and cause megacolon • Syn: ↑Hirschsprung s disease • Hypernyms: ↑genetic disease, ↑genetic disorder … Useful english dictionary
megacolon — ▪ pathology massive enlargement and dilation of the large intestine (colon). The two main types of the syndrome are congenital megacolon, or Hirschsprung disease, and acquired megacolon. In congenital megacolon, the lowermost portion of the … Universalium
congenital disease — noun a disease or disorder that is inherited genetically • Syn: ↑genetic disease, ↑genetic disorder, ↑genetic abnormality, ↑genetic defect, ↑inherited disease, ↑inherited disorder, ↑hereditary disease, ↑ … Useful english dictionary
Megacolon — Classification and external resources ICD 10 K59.3 ICD 9 564.7 … Wikipedia
megacolon — A condition of extreme dilation of the colon. SYN: giant colon. acquired m. m. occurring on the basis of an acquired disease; occurs in inflammatory bowel disease (toxic m.) and Chagas … Medical dictionary
Congenital central hypoventilation syndrome — Failure from birth of central nervous system control over breathing while asleep. There are usually no breathing problems while awake. The involuntary (autonomic) control of respiration is impaired, but the voluntary control of ventilation which… … Medical dictionary
megacolon — noun an abnormal enlargement of the colon; can be congenital (as in Hirschsprung s disease) or acquired (as when children refuse to defecate) • Hypernyms: ↑colon * * * ˈ ̷ ̷ ̷ ̷ˌ noun Etymology: International Scientific Vocabulary mega + colon :… … Useful english dictionary
aganglionic megacolon — congenital m … Medical dictionary
Toxic megacolon — Classification and external resources Micrograph of pseudomembranous colitis, a cause of toxic megacolon. H E stain. ICD … Wikipedia
List of congenital disorders — Numerical * 5p syndrome see Cri du chat A * Aicardi syndrome * Albinism * Amelia and hemimelia * Amniotic Band syndrome * Anencephaly * Angelman syndrome * Aposthia * Arnold Chiari malformation B * Bannayan Zonana syndrome * Bardet Biedl syndrome … Wikipedia