ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Severe pancreatic exocrine insufficiency leading to malabsorption of nutrients is one of the most important late features of chronic pancreatitis. In contrast to other key enzymes, pancreatic synthesis and secretion of lipase is impaired more rapidly, its intraluminal survival is shorter due to its higher susceptibility against acidic and proteolytic denaturation, and its luminal digestive action is hardly compensated by nonpancreatic mechanisms. As a consequence, steatorrhea is in general more severe and occurs several years before clinical malabsorption of protein or starch. Apart from the detrimental effects of nutrient deficiency, profound alterations of upper gastrointestinal secretory and motor functions may be an additional and hitherto underestimated consequence of increased nutrient delivery to distal intestinal sites. Effective reduction of nutrient malabsorption in pancreatic insufficiency requires delivery of sufficient enzymatic activity into the duodenal lumen simultaneously with meal nutrients. Modern enteric-coated pancreatin microsphere preparations attempt to achieve this by optimizing the size of individual microspheres and chemical properties of the coating. However, lipid digestion cannot be completely normalized in most patients by current standard therapy. In the future, acid and protease stable bacterial and fungal lipases with additional pH optima in the acidic milieu or animal or bioengineered human gastric lipase preparations may offer superior therapeutic alternatives. This review first summarizes current knowledge about secretion and luminal fate of pancreatic enzymes and their effects on nutrient digestion in health and chronic pancreatitis. Second, rationale, current standards, options, and future aspects of enzyme replacement therapy are discussed.

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Laxatives and lavage solutions are used in the treatment of constipation and toxic ingestion and also for preparation of the colon before endoscopic or surgical procedures. Several different categories of agents are available for use. These include bulking agents, osmotic agents, secretagogues and agents with direct effects on epithelial nerve or smooth muscle cells, and lubricating agents. Each category has different pharmacologic effects, side effects, and clinical indications. This review summarizes current information about these agents.

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Current practices vary regarding the approach to small polyps discovered during screening flexible sigmoidoscopy. The most common practice is to perform colonoscopy whenever any adenoma is detected, a strategy that generally uses biopsy of polyps ≤ 5 mm in size. However, data suggest that tubular adenomas < 1 cm in size in the distal colon have less predictive value than other distal adenomas for advanced adenomas in the proximal colon. Thus, some centers reserve colonoscopy for distal adenomas with tubulovillous or villous histology, >1 cm in size, or with high-grade dysplasia. At the other end of the spectrum, another school of thought advocates screening colonoscopy, recognizing that most patients with advanced proximal adenomas do not have polyps in their distal colon. Advocates of this approach use any excuse to perform colonoscopy, whether it be a positive fecal occult blood test, minor symptoms, or small polyp at flexible sigmoidoscopy, even if hyperplastic. This review describes the history of the controversy regarding management of findings at flexible sigmoidoscopy, the data pertinent to the controversy, and the basis for the three approaches described above, all of which are currently within the standard of medical care.

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

The prevalence of hepatitis C virus (HCV)-RNA positivity among hemodialysis patients varies between 10 and 70%. Few previous surveys revealed high frequency of seroconversion of HCV-RNA-negative patients over the years of hemodialysis. Only few studies reported HCV genotype variability. We evaluated all 65 patients on chronic hemodialysis in our dialysis unit. All sera positive to anti-HCV on ELISA were retested by reverse transcriptase polymerase chain reaction to HCV-RNA. Sixteen patients were found anti-HCV positive on ELISA, and 8 of them were also PCR positive. Three of these eight patients seroconverted during the year 1995. Four patients had both 1a and 1b genotypes of HCV, coexistence of genotypes 1b and 4a in one patient and genotypes 1a, 1b and 2a in the remaining three patients. Mean serum aminotransferase, duration of dialysis, and number of blood units transfused were significantly higher in the HCV-PCR-positive patients compared with the HCV-PCR-negative patients. Because strict isolation methods were initiated at the end of 1995, not one new case of HCV among dialysis patients was found in 1998, although new hemodialysis patients were diagnosed as having HCV. In conclusion, genotypes 1a and 1b, as is true for the general population in Israel, were also the predominant genotypes among hemodialysis patients; the coexistence of more than one genotype is common among hemodialysis patients; seroconversion is common among these patients and strict isolation methods are efficient and should be recommended.

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Constipation is a common condition affecting millions of people throughout the world. The present study aimed to determine the effect of extra fluid intake, as recommended by many primary care physicians and gastroenterologists, on the actual stool output in normal healthy volunteers. We recruited 15 healthy volunteers (aged 23-46 years, mean 30.1) without any significant history of diarrhea or constipation to participate in our study. Nine subjects underwent extra intake of isotonic fluids (Gatorade), whereas the remainder received extra free water over their baseline. During period I (3 days), baseline diet and fluid intake were determined by a registered dietitian. During periods II and III (2 days each), the volunteers in each group increased their fluid intake by 1 and 2 1 of isotonic (Gatorade) and hypotonic solution (water), respectively. Period IV (2 days) completed the study with the volunteers returning to their baseline fluid intake. Urine and stool outputs were measured in these volunteers. Additional increase in fluid intake (isotonic or free water) did not result in a significant change in stool output. However, there was a significant increase in urine output (P< 0.05). Despite common medical advice to consume extra fluid for constipation, our results indicate that extra fluid intake in normal healthy volunteers did not produce a significant increase in stool output.

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

A through-the-scope endoscopic balloon dilatation technique and acid-reducing medication was used in 46 consecutive patients (median age, 55; range, 21-88 years) with benign gastric outlet obstruction. In five patients, dilatation was not technically possible. In 41 patients, 122 dilatations (median, 2; range, 1-9 per patient) were performed without morbidity. Ninety-four procedures were successful (77%) at the initial attempt (able to pass a 12-mm endoscope into the duodenum at the end of the procedure). Median follow-up in the 41 patients was 19 (range, 1-78) months. Thirteen patients (32%) required subsequent surgery; 8 had delayed operation for persistent symptoms (1-28 months after the first dilatation), 1 had surgery during the initial hospital admission, and 4 required emergency surgery for other ulcer complications (3 perforation, 1 bleeding). Of the 28 patients who had only balloon dilatation and medical therapy, 11 are asymptomatic (4 with active ulceration), 9 have mild symptoms (Visick 2), and 3 have persistent symptoms (Visick 3). One patient was lost to follow-up and four patients have died (one from an ulcer-related complication). Balloon dilatation and sustained acid-reducing therapy with regular endoscopic surveillance should be first-line treatment of peptic pyloroduodenal strictures, because the procedure is safe and is likely to be successful in half of the patients in whom dilatation is technically possible.

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Gastroesophageal reflux disease (GERD) accounts for up to 60% of patients with noncardiac chest pain (NCCP). Twenty-four-hour esophageal pH monitoring has been considered the most sensitive test for identifying acid reflux as the probable cause for chest pain. It is unclear if there is a correlation between the degree of esophageal acid exposure as determined by 24-hour esophageal pH monitoring and symptom improvement during a short course of high-dose omeprazole (the omeprazole test) in patients with NCCP due to GERD. Twenty-three patients with GERD-related NCCP were studied. All patients were referred by a cardiologist and evaluated by upper endoscopy and 24-hour esophageal pH monitoring. Diagnosis of GERD was defined by one or both tests being abnormal. Subsequently, patients underwent baseline symptom intensity assessment during 1 week off therapy followed by 1 week on therapy with high-dose omeprazole (40 mg A.M. and 20 mg P.M.). There was a statistically significant correlation between the esophageal acid exposure by 24-hour esophageal pH monitoring and the change in symptom intensity score after treatment. However, there was no significant correlation between the pH values and symptom intensity score during baseline or during the omeprazole test. In patients with GERD-related NCCP undergoing the omeprazole test, 24-hour esophageal pH monitoring has a therapeutic predictive value in addition to its diagnostic merit. Patients with greater esophageal acid exposure appear to have a greater response to antireflux treatment.

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Radiotherapy-induced mucositis decreases the quality of life by impairing eating, swallowing, and talking and by disturbing sleep. Mucositis may also predispose to local and systemic infections and may cause interruption of radiotherapy course. We studied the efficacy of sucralfate suspension in the prevention and management of oral mucositis and pain during radiotherapy in a double-blind, placebo-controlled, randomized, prospective trial. Twenty-eight patients with head and neck cancer were included in the study. The patients were randomized to use either sucralfate mouth washing (n = 18) or placebo washing (n = 10) during irradiation. Oral mucositis and symptoms were assessed by the same physician using Radiation Therapy Oncology Group Acute Radiation Morbidity Scoring criteria. All patients developed varying degrees of radiation-induced mucositis. Grade 4 mucositis was not encountered in any patient. One patient had grade 1, seven patients grade 2, and two patients grade 3 mucositis in placebo group. In sucralfate group, nine patients each had grade 1 and grade 2 with no grade 3 mucositis. Patients in the sucralfate group experienced significantly lower degree of mucositis than placebo group (p< 0.05). Sucralfate mouth washing is beneficial in decreasing the intensity of radiation-induced mucositis and oral discomfort. It is cheap, easy to administer with no serious side effect, and may be routinely used in patients receiving head and neck radiotherapy.

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0192-0790    

出版商:OVID    

年代:1999

数据来源: OVID