1/12. megacolon in myotonic dystrophy caused by a degenerative neuropathy of the myenteric plexus.A 32-yr-old man with myotonic dystrophy had a left hemicolectomy performed because of a megacolon. The colonic mucosa, smooth muscle, and connective tissue appeared normal by hematoxylin and eosin and trichrome stains and transmission electron microscopy. In contrast, the myenteric plexus had markedly fewer neurons than normal on the hematoxylin and eosin stains. silver staining of the plexus revealed degeneration and decreased numbers of argyrophilic neurons, which were smaller and had fewer processes and a more uneven staining quality than controls. Many axons were fragmented, and increased numbers of glial cell nuclei were present in the plexus. Degenerative changes in the neurons were present in a patchy distribution on transmission electron microscopy. immunohistochemistry revealed a decrease of the substance p- and enkephalin-immunoreactive fibers in the muscularis externa. This suggests that colonic motor dysfunction associated with myotonic dystrophy may be caused by a visceral neuropathy that involves the substance p- and enkephalin-immunoreactive fibers of the smooth muscle.- - - - - - - - - - ranking = 1keywords = plexus (Clic here for more details about this article) |
2/12. Parkinson's disease and megacolon: concentric hyaline inclusions (lewy bodies) in enteric ganglion cells.Concentric hyaline inclusions (lewy bodies), found in the cytoplasm of pigmented and nonpigmented neurons, are considered characteristic of idiopathic Parkinson's disease. The finding of cytoplasmic inclusions identical to lewy bodies in ganglion cells of the colonic myenteric plexus in a patient with idiopathic Parkinson's disease and acquired megacolon suggests primary involvement of the enteric nervous system by Parkinson's disease.- - - - - - - - - - ranking = 0.14285714285714keywords = plexus (Clic here for more details about this article) |
3/12. myxedema megacolon after external neck irradiation.myxedema megacolon is a rare manifestation of hypothyroidism. It may respond to appropriate treatment but is sometimes irreversible, resulting in fatal complications. Two possible mechanisms to explain the colonic atony include (1) myxomatous infiltration of the submucosa with separation of the muscular fibers from the ganglia of Auerbach's plexus, and (2) severe autonomic neuropathy affecting the extrinsic nerves to the colon and the myenteric plexus. histology from our case supports the first proposed mechanism. Urecholine challenge and manometric measure response may help predict reversibility of colonic atony. Treatment should be individualized and should include factors such as age, duration of symptoms, and other medical illness. Low-dose oral or intravenous triiodothyronine is effective. hypothyroidism following external radiation of the neck for lymphoma is not uncommon, and the risk increases following one or more lymphangiograms. Such patients should be followed up with regular TSH estimations for at least three years.- - - - - - - - - - ranking = 0.28571428571429keywords = plexus (Clic here for more details about this article) |
4/12. megacolon and neurofibromatosis: a neuronal intestinal dysplasia. Case report and review of the literature.This study presents the case of a patient with neurofibromatosis and megacolon. A diffuse, but patchy abnormality of neural tissue was present throughout the colon, especially in the myenteric plexus, but also in the submucosal plexus, smooth muscles, and lamina propria. This consisted of (a) a marked decrease in the number of argyrophilic neurons within the myenteric plexus, enlargement and deformity of those neurons present, and a marked increase of nerve fibers and nerve tract size in the myenteric plexus; (b) a proliferation of neurons and nerve fibers within the smooth muscle and submucosa; and (c) a proliferation of nerve fibers within focal areas of the lamina propria. The relationship of this case to previously reported cases of neuronal intestinal dysplasia and plexiform neurofibromatosis is discussed. Surgical treatment may be necessary and the surgical options are reviewed.- - - - - - - - - - ranking = 0.57142857142857keywords = plexus (Clic here for more details about this article) |
5/12. Primary myenteric plexus alterations as a cause of megacolon in Von Recklinghausen's disease.This is a case report of a megacolon in a 26 years old male patient having typical von Recklinghausen's disease. Exploratory laparotomy shows no neurofibroma on digestive tract. myenteric plexus study of colic resection specimen following B. Smith technique reveals marked alterations. These alterations are both quantitative (hyperhypoganglionosis) and qualitative (ganglion cells are irregular in shape and size, dendritic processes are hypertrophic, irregular; schwannosis; no inflammatory infiltration). The patient suffers no more transit disorders after adequate resection of this megacolon.- - - - - - - - - - ranking = 0.71428571428571keywords = plexus (Clic here for more details about this article) |
6/12. hyperplasia of the myenteric plexus. Its association with early infantile megacolon and neurofibromatosis.An infant with cutaneous criteria for neurofibromatosis had hyperplasia of the intestinal myenteric plexus and a clinical presentation mimicking Hirschsprung's disease. Many of his phenotypic features are also found in multiple endocrine neoplasia type IIb, a condition in which hyperplasia of the myenteric plexus is common. This case illustrates the overlapping nature of neural crest-derived conditions and the variable presentation of megacolon (ganglionic or aganglionic) in infancy.- - - - - - - - - - ranking = 0.85714285714286keywords = plexus (Clic here for more details about this article) |
7/12. Localized and disseminated forms of neuronal intestinal dysplasia mimicking Hirschsprung's disease.Neuronal intestinal dysplasia is characterized by structural changes consisting of hyperplasia of the myenteric plexus, an increase of the acetyl cholinesterase activity and the formation of giant ganglia. The condition gives rise to signs and symptoms similar to Hirschsprung's disease. Neuronal intestinal dysplasia can occur as a clinical entity itself in a localized or disseminated form. It may also accompany Hirschsprung's disease either as a localized defect or as a disseminated disorder of the entire intestinal tract. In localized forms, resection of the entire diseased segment is curative. Disseminated forms often have a fetal outcome despite ileostomy and colectomy. It is conceivable that differences in the severity of symptoms depend upon the development or absence of sympathetic innervation.- - - - - - - - - - ranking = 0.14285714285714keywords = plexus (Clic here for more details about this article) |
8/12. leopard syndrome, a neural crest disorder: a case report.A case of leopard syndrome with full clinical expression is reported. In addition to the cardinal signs of the syndrome this patient presented some abnormalities which have not been previously described such as macroglossia, multiple dental anomalies, basilar impression and platybasia, megacolon, hypertrophy of clitoris and anal ectopy. The presence of dental anomalies and megacolon may represent involvement of the dental papillae and myenteric plexus favoring the view that the syndrome results from a derangement of the neural crest elements.- - - - - - - - - - ranking = 0.14285714285714keywords = plexus (Clic here for more details about this article) |
9/12. A rare case of achalasia coexistent with sigmoid megacolon and associated with epilepsy.A case of achalasia coexistent with sigmoid megacolon in a 38-year-old man with known epilepsy is described. The patient was referred to the Ryukyu University Hospital with a 4-year history of dysphagia and heartburn and a 1-year history of abnormal bowel movement. On admission, upper gastrointestinal (GI) series demonstrated a dilated, tortuous thoracic esophagus with a flask-type configuration. barium enema studies showed a dilated sigmoid colon from the rectosigmoid junction to the descending colon. Myotomy (modified Jekler-Lhotka's procedure) for achalasia and simple sigmoidectomy for sigmoid megacolon were carried out. The biopsied wall of the narrowed esophageal segment at operation showed decreased numbers of ganglion cells in Auerbach's plexus and atrophy of the muscle fibers. The resected dilated sigmoid colon revealed degeneration and markedly decreased numbers of ganglion cells in Auerbach's and Meissner's plexuses. The patient's postoperative course was uneventful and he has been doing well since surgery. The present case is very interesting and to our knowledge, such a case is rare in the literature. We believe that the abnormalities of the ganglion cells may be due to the same etiologic factor as the sigmoid megacolon. The association of the two pathologic processes is discussed, together with a brief review of the literature.- - - - - - - - - - ranking = 0.28571428571429keywords = plexus (Clic here for more details about this article) |
10/12. biliary tract complications in patients with hypoganglionosis and chronic idiopathic intestinal pseudoobstruction syndrome.The biliary tract system was studied in two patients with hypoganglionosis and chronic idiopathic intestinal pseudoobstruction syndrome (CIIPS) to evaluate manifestations of these diseases, especially as for underlying motility disorder. In a 3-year-old boy with hypoganglionosis, cholelithiasis was diagnosed and the gallbladder specimen showed a markedly hypoplastic neural plexus on histopathology as was found in his total alimentary tract. In a 2-year-old girl with CIIPS, echo-guided gallbladder wall motility testing demonstrated an impaired response to a ceruletide diethylamine stimulation. These clinical experiences in two patients suggest that these pathological entities may be frequently associated with biliary tract complications not only due to a consequence of total parenteral nutrition, but also due to a possible intrinsic involvement of biliary tract dysmotility.- - - - - - - - - - ranking = 0.14285714285714keywords = plexus (Clic here for more details about this article) |
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