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At least 73 records · Page 4Linked to original sources
PubMed1984

Assessment of anorectal motility measurements in the management of adult megacolon.

Anorectal motility was studied in 23 patients with adult megacolon. A balloon was used for rectal distension, and electrical signals from the anal canal or rectal mucosa were monitored with a silver/silver chloride electrode. Intraluminal pressure was measured by a pressure transducer linked to the vicinity of the electrode via a polythene tube. Responses to rectal distension provided a means of distinguishing patients with adult Hirschprung's disease from ones with idiopathic megacolon. Some patients with the latter condition showed an elevation of mean anal canal pressure relative to that in normal subjects. There was no statistically significant difference in slow-wave frequency in the anal canal between patients and adult megacolon and normal subjects. The fall in anal canal pressure associated with rectal distension was correlated with a decline in the amplitude of slow-wave electrical activity. The measurement of anorectal motor parameters was of value in the management of adult megacolon.

Anal Canal↗
PubMed1983

[Megacolon as a rare complication of diabetes mellitus].

The clinical and radiological features of diabetic megacolon and gastroparesis occurring in a 48-year-old woman are presented. The only two other well-documented cases of diabetic megacolon from the literature are reviewed. The predominant dilatation of the sigmoidal colon in the setting of a generalized megacolon may be, especially if associated with bladder atony, a clue to the diagnosis of the diabetic nature of a megacolon.

Constipation↗
PubMed1995

[An increased incidence of megacolon in psychiatric and neurologic patients].

The incidence of megacolon is elevated in neuropsychiatric patients. Siegmund was the first, in 1935, to report on the development of megacolon and megasigmoid as the result of chronic atropine therapy of patients with postencephalitic parkinsonism and the associated risk of stercoraceous ulcers and ileus or even sudden death. The etiology of increased frequency of megacolon among neuropsychiatric patients is assumed to be nonuniform, and to include organic defects of centers of the autonomous nervous system in the diencephalon and/or hypothalamous, pharmacodynamic, psychogenic and neurogenic influences on the autonomic nervous system, akinesia and increased obstipation among psychiatric patients, insufficient pressure in the abdominal wall especially in the mentally retarded, with frequently associated weakness of the connective tissue. In cases of long-term therapy with psychotropic drugs the anticholinergic side effects with the risk of megacolon and resulting ileus, sometimes with fatal outcome should be borne into mind.

Cholinergic Antagonists↗
PubMed1994

A patient with localized megacolon and intractable constipation: evidence for impairment of colonic muscle tone.

There have been descriptions of a variety of abnormalities in motor function in patients with megacolon; however, colonic tone in megacolon has not been measured to date. Recent data suggest that colonic hypertonicity of carcinoid diarrhea is measurable with an electronic barostat. Using a barostat method, we have evaluated colonic transit, motility, and tone in a patient with severe constipation and localized chronic megacolon. Transit measurements showed a significant delay beyond the mid transverse colon; motility studies in the dilated region of colon showed abnormally low tone but normal phasic contractility, as measured by the barostat. In contrast, manometry showed low amplitude contractions relative to control data; this discrepancy probably results from the large capacity of the segment of colon examined. Chronic megacolon can be associated with abnormal colonic tone, which can be measured by means of an electronic barostat.

Aged↗
PubMed1994

Idiopathic megacolon in the BB rat.

It has been assumed that idiopathic megacolon occurring in the spontaneously diabetic BB rat results from metabolic decompensation associated with diabetes. In a large prospective necropsy study we have documented the incidence of idiopathic megacolon and its distribution between diabetic and non-diabetic animals in the BB rat colony in Edinburgh. A significantly increased incidence of megacolon was found in non-diabetic rats in the diabetes-prone subline compared with diabetic rats in the diabetes-prone subline and with non-diabetic rats in the diabetes-resistant subline. Affected animals were found to have an inflammatory infiltrate in the wall of the large bowel with destruction of both autonomic ganglia and muscularis propria. These necropsy observations indicate that megacolon cannot be a result of the metabolic disturbance due to the hyperglycaemia associated with diabetes.

Age Factors↗
PubMed2006

Treatment of megacolon and megarectum.

Patients presenting with megacolon and megarectum require extensive specialized testing to distinguish underlying Hirschsprung's disease from other secondary causes. Diagnostic testing and long-term treatment are best initiated after disimpaction has been achieved, by large-volume tap water enemas and/or oral colonic lavage with polyethylene glycol. With intensive treatment (including biofeedback if pelvic floor dysfunction is present), at lease one half of patients can avoid surgery. Maintenance therapy relies on daily use of osmotic laxatives. Stimulant laxatives are used intermittently as rescue treatments if there has not been a satisfactory bowel movement in 3 days. Patients with idiopathic megacolon or megarectum may require surgery if they have refractory symptoms. Depending on age, pelvic floor, and anal sphincter function, patients who have isolated megacolon can be treated with either subtotal colectomy with ileorectostomy or diverting loop ileostomy. Patients with isolated megarectum can be treated with either proctectomy and coloanal anastomosis or vertical reduction rectoplasty. Patients who have combined megacolon and megarectum can be offered diverting loop ileostomy or, if pelvic floor function is normal and they wish to avoid stoma, total proctocolectomy with ileal pouch-anal anastomosis.

Journal Article↗
PubMed2006

Interstitial cells of Cajal in patients with chagasic megacolon originating from a region of old endemicity.

UNLABELLED: Megacolon is the second most frequent and most important digestive manifestation of Chagas' disease. It is characterized by motor disorders and dilatation of the distal segments of the colon. Several theories have been presented to explain the physiopathology of chagasic megacolon, e.g. the plexus theory. OBJECTIVE: In the present study the distribution of interstitial cells of Cajal (ICC) was evaluated in colon biopsies from chronic chagasic patients originating from a region of old endemicity for Trypanosoma cruzi and for comparison in subjects with other colon disorders. The chagasic patients had been submitted to colectomy for the investigation of other possible mechanisms underlying the physiopathogenesis of megacolons. DESIGN STUDY: Twenty-two colon biopsies (15 from chagasic patients and 7 from nonchagasic patients) were examined. ICC were identified by immunohistochemistry by using the anti-CD117 antibody. The number of ICC was determined in longitudinal and circular muscle layers and in the myenteric plexus, and the results were analyzed by the Kruskal-Wallis and Student t-tests. RESULTS: A reduced number of ICC was observed in all layers and in the myenteric plexus of patients with chagasic megacolon (P<0.05). CONCLUSIONS: We conclude that the physiopathological manifestations observed in the large bowel of chagasic patients originate from alterations that occur in the ICC, which play an important role in the control of gut motility.

Journal Article↗
PubMedDate not supplied

[Congenital megacolon presented as fecaloma and urinary tract infection. Report of one case].

A 5-month old boy was admitted with urinary tract infection. While doing the voiding cystogram, the bladder was found to be pushed to the right side by a soft tissue mass. Through CT scan examination, the mass revealed to be a fecaloma. Through rectal suction biopsy and barium enema study for megacolon, it was proved to be a case of congenital megacolon. A pull-through operation for megacolon was carried out. He recovered quickly, and was discharged 10 days later. We make this report in order to discuss this rare presentation which may occur in congenital megacolon.

Fecal Impaction↗
PubMed1980

An assessment of anorectal motility in the management of adult megacolon.

Anorectal motility measurements have been performed on 19 patients with adult megacolon and the results compared with 12 normal subjects. Adult Hirschsprung's disease (4 patients) was recognized by the absence of anal canal inhibition on rectal distension (normal mean inhibition 21.9 +/- 2.3 mmHg). Seven patients with non-Hirschsprung's megacolon (idiopathic) had an elevated anal pressure (mean 90.4 +/- 7.0 mmHg). These patients were treated with repeated anal dilatation. Eight further patients had normal anal canal pressures (mean 33.2 +/- 11.7 mmHg) and were treated with enemas and regular suppositories. Little overall clinical improvement resulted in this group and 1 patient underwent subtotal colectomy. Measurements of anorectal motility have been found to assist in the management of adult megacolon.

Action Potentials↗
PubMed1980

Risk factors in toxic megacolon.

A retrospective analysis of data from a series of 22 patients with toxic megacolon complicating ulcerative colitis was performed in an attempt to detect factors associated with the fatal outcome of the attack. Of the 25 clinical findings studied, significant differences between survivors (17) and nonsurvivors (5) were observed in only seven. In nonsurvivors, duration of the disease was longer and blood pH and standard bicarbonate levels higher, whereas serum potassium, calcium, phosphorus, and beta-globulins were lower. Discriminant analysis showed that three pairs of features, namely potassium-beta-globulins, potassium-bicarbonate, and potassium-blood pH provided a good discrimination between survivors and nonsurvivors. Results of this study indicate that the severity of the electrolyte and metabolic disorder appears to be an important risk factor in toxic megacolon. Intensive fluid and electrolyte replacement should therefore be considered a crucial point for successful management of toxic megacolon.

Adult↗
PubMed1992

Pseudomembranous colitis leading to toxic megacolon associated with antineoplastic chemotherapy. Report of a case and review of the literature.

Pseudomembranous colitis and toxic megacolon are rare complications of antineoplastic chemotherapy. Twelve cases of pseudomembranous colitis and four cases of toxic megacolon, both occurring as complications of chemotherapy, have been reported in the medical literature. These diseases occurred as separate and distinct entities. Fulminating pseudomembranous colitis leading to toxic megacolon in the setting of chemotherapy has not been previously reported. We report such a case, emphasizing its atypical presentation and rapid, fulminant course.

Aged↗
PubMed1995

Toxic megacolon complicating pseudomembranous enterocolitis.

PURPOSE: Toxic megacolon is a rare complication of pseudomembranous enterocolitis. We reviewed our recent experience with this complication. METHODS: The first five patients of the series were studied retrospectively, and six others were followed prospectively. RESULTS: Between June 1992 and May 1994, 11 patients (8 male, 3 female) developed toxic megacolon secondary to pseudomembranous enterocolitis. Mean age was 60.7 +/- 11.8 (range, 40-79) years. Presenting symptoms and signs included diarrhea, 100 percent; malaise, 91 percent; abdominal pain, 82 percent; abdominal distention, 82 percent; abdominal tenderness, 72 percent; anemia less than 12 gm, 72 percent; albumin less than 3 gm, 64 percent; tachycardia greater than 100, 55 percent; fever greater than 38.5 degrees celsius, 45 percent; shock or hypotension, 45 percent. Predisposing factors included antibiotics, 64 percent; immunosuppressants or chemotherapy, 36 percent; antidiarrheals, 27 percent; and barium enema in one patient. Five patients (45 percent) had more than one predisposing factor. X-rays showed transverse colon dilation and loss of haustrations in eight patients (72 percent), with a mean diameter of 9.9 +/- 3.4 cm. Flexible proctosigmoidoscopy showed pseudomembranes in all scoped patients, and toxin assay for Clostridium difficile was positive in all patients. One patient had emergency surgery. Ten patients were initially treated medically with nasogastric suction and intravenous resuscitation (90 percent) and antibiotics (100 percent), usually in the intensive care unit (80 percent). Four patients did not respond and underwent surgery; two others improved, then deteriorated, and also underwent surgery. Altogether, 7 of 11 patients (64 percent) underwent surgery. Three patients (27 percent) responded well to medical treatment. One patient was deemed too ill to undergo surgery and died. Mean delay to surgery was 3.0 +/- 1.3 days. No sealed or overt perforation was found at laparotomy. All patients who underwent surgery had a subtotal colectomy, with either a Hartmann's stump (71 percent) or a mucous fistula (29 percent). Eventually, five of seven patients who were operated on and two of four medically treated patients died (overall mortality, 64 percent). Only one patient underwent closure of ileostomy and anastomosis. CONCLUSION: Toxic megacolon complicating pseudomembranous enterocolitis is a serious problem that carries a high morbidity and mortality rate, regardless of treatment.

Adult↗
PubMed2001

Cell-mediated immune response in megacolon from patients with chronic Chagas' disease.

PURPOSE: The mechanisms that control chronic infection in vivo and the immunologic mechanisms involved in the pathogenesis of chagasic megacolon are not completely characterized. Although autoimmunity may play a role in the pathogenesis of Chagas' disease, recent studies, both in mice and in humans, suggest a positive association of tissue parasitism, inflammation, and severity of lesions. The aim of this study was to evaluate the role of inflammatory cells and the subclasses of lymphocytes involved in neuropathic lesions in the colon of patients who underwent resection for advanced megacolon. METHODS: Specimens from 23 patients were selected based on histopathologic analysis. Paraffin-embedded tissue blocks were sectioned and evaluated by immunohistochemistry for cluster of differentiation 3, cluster of differentiation 8, cluster of differentiation 20, and natural killer cell antibodies by an avidin-biotin peroxidase method. RESULTS: Almost all myenteric plexuses were damaged, characterized by degenerative changes, necrosis of ganglion cells, and inflammatory response. Mild lymphocytic infiltration around degenerated and normal ganglion cells was observed in all cases. Collagen fibers and mononuclear cells surrounded some ganglion cells. Most of the inflammatory cells were lymphocytes, identified as cluster of differentiation 3-positive cells. Cluster of differentiation 8-positive lymphocytes were associated with degenerated ganglion cells. Natural killer cell antibodies were detected in a lower proportion of cells and were distributed between muscle layers or in proximity to the myenteric plexus. All these findings were also observed in the submucosal plexus. Cluster of differentiation 20-positive lymphocytes were not present in muscle layers or in the vicinity of either plexus. CONCLUSION: Pathogenesis of the megacolon is based on a continuous process of ganglion cell damage with participation of T lymphocytes expressing cluster of differentiation 8 and natural killer cell membrane antigens. B lymphocytes do not take part in the chronic inflammatory reaction.

Antibody Formation↗
PubMed1994

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.

Adult↗
PubMed1979

A manometric assessment of anorectal pressures and its significance in the diagnosis of Hirschsprung's disease and idiopathic megacolon.

Anorectal manometric studies were performed on nine patients with Hirschsprung's disease and ten patients with idiopathic megacolon for the purpose of differentiation, comparing with those of the normal subjects. The anorectal reflex was absent in all nine of the patients with Hirschsprung's disease while in all of ten patients with idiopathic megacolon rectal distension produced a relaxation in the anal canal like that of the normal subjects. Manometric studies proved to be a reliable and non-invasive technique for the diagnosis of Hirschsprung's disease and were of particular value as simple screening tests in patients with a clinical suggestion of this disease. The manometric studies of the patients with Hirschsprung's disease or idiopathic megacolon in the present series also demonstrated that the pronounced internal sphincter contraction combined with a total absence of reflex relaxation or an inadequate response of the sphincter to rectal distension might be responsible for the obstructive symptoms in these diseases.

Adolescent↗
PubMedDate not supplied

Toxic idiopathic megacolon: fatal outcome in a mentally retarded adolescent.

The case of an 18-year-old mentally retarded boy who had long standing idiopathic megacolon and pica is presented. Acute toxic dilatation of the colon complicating pseudomembranous colitis developed, with a rapidly fatal outcome. No similar case of relatively benign idiopathic megacolon complicated by pseudomembranous colitis and toxic megacolon has been reported. The pathophysiology of this rare combination is discussed.

Adolescent↗
PubMed2000

[Idiopathic megacolon. New findings on histopathology and musculo-mechanical causes].

Nineteen native surgical specimens of an idiopathic megacolon were histopathologically investigated and a lack of the tendon-like collagen III movement net of circular and longitudinal muscles observed, including a lack of the connective tissue layer of myenteric plexus. This disease of the muscularis propria could be considered as a desmolysis, a hypoplastic or an aplastic desmosis. With reference to the normal muscle mechanics of the gut, it is shown that the pathogenetic principle of the idiopathic megacolon consists in absence of the tendon-like connective tissue net in the muscularis propria which results in a lack of peristalsis of the gut, despite of a regular enteric innervation. This finding demonstrates that an idiopathic megacolon can be histopathologically verified in whole-mount biopsies and referred for curative surgical treatment.

Adolescent↗
PubMed1998

Evaluation of specific herpes DNA viruses in idiopathic megarectum and idiopathic megacolon.

PURPOSE: The aetiology of idiopathic megarectum and idiopathic megacolon is unknown. A previous study in patients with chronic idiopathic intestinal pseudo-obstruction, a condition also associated with a dilated gut, identified the possible involvement of herpes viruses. This study therefore aimed to determine whether these viruses may also be implicated in the pathogenesis of these conditions. METHODS: Resected large bowel from three patients with idiopathic megarectum and three patients with idiopathic megacolon were studied. Histology for viral inclusions and nested polymerase chain reaction (PCR) using specific primers for cytomegalovirus, Epstein-Barr virus, herpes simplex virus type 1 and varicella zoster virus was performed. DNA was extracted from paraffin-embedded blocks by proteinase K and phenol chloroform extraction. RESULTS: Viral inclusions were not seen. PCR failed to identify DNA of the four herpes viruses tested. CONCLUSION: Patients with idiopathic megarectum or idiopathic megacolon may have subtle abnormalities of the enteric innervation, but these do not appear to be attributable to the neurotropic effects of the herpes viruses studied.

Cytomegalovirus↗