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Biomedical subjects

A Vanagunas

Publications and source records attributed to A Vanagunas.

18 recordsLinked to original sources
PubMed1997

Eradication of Helicobacter pylori and regression of B-cell lymphoma.

There is an increasing body of evidence implicating a causal association between Helicobacter pylori and the development of mucosa-associated lymphoid tissue (MALT) associated B-cell gastric lymphoma. Investigators have noted that almost all patients with H pylori-associated chronic gastritis develop lymphoid follicles. Some of these patients demonstrate infiltration of B cells and lymphoepithelial lesions typical of MALT lymphoma. When gastric tissue from patients with gastric B-cell lymphoma is analyzed for H pylori infection, the overwhelming majority of patients demonstrate this condition. Epidemiologic nested case-control studies have shown that patients with gastric non-Hodgkin's lymphoma are substantially more likely that matched controls to have H pylori infection. This situation may be analogous to the linkage between chronic Epstein-Barr virus and lymphoma. The mechanisms inducing the development of lymphoma are not clear, but it has been suggested that chronic infection with H pylori results in the stimulation of H pylori-responsive T cells which in turn activate B cells with the subsequent development of a mutation to a monoclonal B-cell population. Recent evidence indicates that cure of H pylori infection produces regression of MALT lymphoma within 3 to 12 months in approximately 75% of antibiotic-treated patients. Individual responsiveness remains unpredictable, however, and careful and prolonged endoscopic and histologic follow-up is needed. Large, well-controlled studies are necessary, however, to determine the duration of 'cure' and the appropriate setting for treatment.

Helicobacter Infections↗
PubMed1997

Short chain fatty acid rectal irrigation for left-sided ulcerative colitis: a randomised, placebo controlled trial.

BACKGROUND: Short chain fatty acid (SCFA) deficiency is associated with colitis in animals and humans, and the mucosal metabolism of these compounds is decreased in ulcerative colitis. AIMS: To assess the efficacy of topical SCFA treatment in ulcerative colitis. PATIENTS AND METHODS: 103 patients with distal ulcerative colitis were entered into a six week, double-blind, placebo controlled trial of rectal SCFA twice daily; patients who were unchanged on placebo were offered SCFA in an open-label extension trial. RESULTS: Of the 91 patients completing the trial, more patients in the SCFA treated than in the placebo treated group improved (33% v 20%, p = 0.14, NS). Those on SCFA also had larger, but statistically non-significant, reductions in every component of their clinical and histological activity scores. In patients with a relatively short current episode of colitis (< 6 months, n = 42), more responded to SCFA than to placebo (48% v 18%, p = 0.03). These patients also had larger, but statistically non-significant, decreases in their clinical activity index (p = 0.08 v placebo). Every patient who improved used at least five of six of the prescribed rectal SCFA irrigations, whereas only 37% who did not improve were as compliant. In the open-label extension trial, 65% improved on SCFA; these patients also had significant reductions (p < 0.02) in their clinical and histological activity scores. CONCLUSIONS: Although SCFA enemas were not of therapeutic value in this controlled trial, the results suggest efficacy in subsets of patients with distal ulcerative colitis including those with short active episodes. Prolonged contact with rectal mucosa seems to be necessary for therapeutic benefit.

Acute Disease↗
PubMed1996

Progression of gastritis to monoclonal B-cell lymphoma with resolution and recurrence following eradication of Helicobacter pylori.

OBJECTIVE: To follow a patient with Helicobacter pylori-associated gastritis by performing serial endoscopic biopsies to observe the histologic progression of the gastritis to a monoclonal B-cell lymphoma with resolution and subsequent recurrence following eradication of H pylori organisms. DESIGN: A case report of a patient followed over 3 years. MAIN OUTCOME MEASURES: Characteristics of the gastric mucosa as determined by histologic and gene rearrangement studies on multiple random biopsies obtained serially before and after the eradication of H pylori organisms. RESULTS: A progression from H pylori-associated gastritis through lymphoid hyperplasia to a monoclonal B-cell lymphoma was observed. With the techniques used, a resolution of the lymphoma was observed on eradication of H pylori organisms, with a subsequent recurrence of the lymphoma 15 months later, despite the absence of H pylori organisms. CONCLUSION: The observations made of this patient support an association between H pylori and the development of a gastric monoclonal B-cell lymphoma. This lesion appears to develop in the setting of gastritis and progresses through lymphoid hyperplasia followed subsequently by the lymphoma. We speculate that this process is initially antigen driven by the organism and may subsequently become autonomous as genetic damage is accumulated, so that eradication of H pylori organisms will lead to regression of the lesion to the degree that there are autonomously proliferating cells present.

Biopsy↗
PubMed1994

Endoscopic ultrasound in the evaluation of Barrett's esophagus: a preliminary report.

OBJECTIVE: Endoscopic screening of Barrett's esophagus (BE) for dysplasia is imprecise and controversial. Endoscopic ultrasound (EUS) allows a detailed circumferential image of the esophageal wall. Our objective in this study was to assess the utility of EUS for surveillance in Barrett's esophagus. METHODS: Consecutive patients with proven BE undergoing endoscopy were evaluated with EUS. Esophageal wall thickness (EWT) was measured as the distance from the balloon-mucosal interface to the outermost hyperechoic line. EWT was determined as the average of all measurements done every 2-3 cm along the esophagus. Identical measurements were performed in a series of controls. RESULTS: Fifteen patients with BE and 13 control patients were studied. Two patients had focal submucosal thickening on EUS with EWTs of 10 mm and 7 mm. Surgical resection of the esophagus in these two cases with high-grade dysplasia revealed submucosal carcinoma at the area of EUS-documented thickening. The mean EWT of controls measured 2.6 mm, nondysplastic BE measured 3.3 mm, and BE with dysplasia measured 4.0 mm. The EWT of both dysplastic and nondysplastic Barrett's was significantly greater than that of the controls (p < 0.02, Student's t test). CONCLUSIONS: 1) As measured by EUS, the esophageal wall is significantly thickened in the columnar-lined portion of Barrett's esophagus. 2) EUS-detected focal thickening may represent submucosal carcinoma in areas of dysplasia and guide early surgery. Thus, EUS may play a role in evaluating the patients with dysplasia in Barrett's esophagus.

Adult↗
PubMed1991

Floating common bile duct stones. A cause of a false negative endoscopic retrograde cholangiogram.

Endoscopic retrograde cholangiography (ERC) is the "gold standard" for the preoperative diagnosis of choledocholithiasis. Air bubbles that can cause a false positive ERC are differentiated from stones by their response to gravitational maneuvers: bubbles rise while stones sink. We report a patient with round, floating common bile duct stones that mimicked air bubbles to be the reason for a false negative ERC.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1990

Peristaltic dysfunction associated with nonobstructive dysphagia in reflux disease.

An evaluation was done of 325 consecutive patients who underwent esophageal manometry to investigate the relationship between solid food dysphagia and peristaltic dysfunction in gastroesophageal reflux disease. All patients with dysphagia were endoscoped to evaluate for mechanical obstruction. Manometry was done focusing on the incidence of peristaltic dysfunction (failed peristaltic sequences or sequences characterized by foci of hypotensive peristalsis). The major finding was that the severity of manometrically demonstrated peristaltic dysfunction in reflux patients correlated with the prevalence of dysphagia. After excluding patients with esophageal rings or strictures from the analysis, the overall prevalence of dysphagia was 39% among the 157 reflux patients. Within this group, 29% of patients with minimal peristaltic dysfunction experienced dysphagia compared to 78% of patients with severe peristaltic dysfunction. We conclude that peristaltic dysfunction should be considered along with mechanical obstruction as a potential cause of dysphagia in patients with gastroesophageal reflux disease.

Deglutition Disorders↗
PubMed1990

Radiation-induced esophageal injury: a spectrum from esophagitis to cancer.

Radiation esophagitis is a common but frequently unrecognized complication of therapeutic radiation to the neck, chest, or mediastinum. The spectrum of injury ranges from acute self-limited esophagitis to life-threatening esophageal perforation. Complications such as stricture or primary esophageal cancer may occur many years after irradiation, and their linkage to radiation may not be considered. Five cases of radiation-induced injury are described, and the spectrum of radiation-induced esophageal injury is reviewed.

Aged↗
PubMed1989

Adequacy of "hot biopsy" for the treatment of diminutive polyps: a prospective randomized trial.

Patients with diminutive polyps in the rectum or sigmoid colon were randomized to "hot biopsy" treatment for either 1) electrocautery for 2 s (fixed duration cautery) or 2) cautery until visible necrosis of the polyp base was evident (variable duration cautery). Sigmoidoscopy was performed 4 wk after treatment to determine the adequacy of polyp eradication. In the fixed duration cautery group, 11 of 21 polyps (52%) were eradicated, compared with 12 of 14 polyps (86%) in the variable duration cautery group (p = 0.04). When analyzed according to whether or not visible necrosis was achieved (some of the polyps in the fixed duration cautery group showed necrosis with 2 s cautery), 19 of 23 polyps (83%) were eradicated when necrosis was evident, compared to 5 of 12 (42%) without necrosis (p = 0.004). We conclude that hot biopsy treatment for diminutive polyps is significantly more effective when visible necrosis is achieved during cautery. Furthermore, even with visible necrosis, there is a 17% failure rate of polyp eradication.

Adenoma↗
PubMed1989

Absence of an upper esophageal sphincter response to acid reflux.

Manometric studies of the upper esophageal sphincter (UES) were done on 17 volunteer subjects and 16 patients with endoscopically evident esophagitis. Subjects entered one or both of two protocols designed to assess the effect of esophageal acid exposure on UES pressure. In protocol 1, continuous 3-h postprandial recordings were obtained; a modified sleeve sensor was used to measure UES pressure, and an intraluminal pH electrode was used to detect occurrences of spontaneous gastroesophageal acid reflux. In protocol 2, UES pressure was continuously monitored during a 10-min control period, followed by a 25-min period of esophageal perfusion with 0.1 N HCl. Our findings were that: 1) basal UES pressure measured during the 3-h recording was similar in the normal volunteers and in the group of patients with esophagitis, 2) episodes of spontaneous gastroesophageal acid reflux were not associated with a change in UES pressure in either the normal volunteers or in the patients with esophagitis, and 3) esophageal perfusion with HCl did not affect the UES pressure in either group, although severe heartburn occurred in most of the esophagitis patients. We conclude that the upper esophageal sphincter exhibits normal basal pressure in patients with esophagitis and that esophageal acid exposure, either spontaneous or experimental, does not affect UES pressure in normal volunteers or in patients with esophagitis.

Adult↗
PubMed1980

Solitary nonparasitic hepatic cyst causing obstructive jaundice.

Solitary nonparasitic hepatic cysts are rarely associated with jaundice and abnormalities of liver function have been attributed to hepatocellular disease in the absence of a separate obstructing lesion of the biliary tree. This case represents the first cholangiographic documentation of a solitary nonparasitic hepatic cyst compressing biliary radicles resulting in obstructive jaundice. The implication for treatment is discussed.

Aged↗
PubMedDate not supplied

Hypermanganesemia in patients receiving total parenteral nutrition.

BACKGROUND: Manganese is one of the trace elements that is routinely administered to total parenteral nutrition (TPN) patients. The recommended daily IV dosage ranges from 100 to 800 MICROg. We have used 500 microg daily. Recent reports have suggested neurologic symptoms seen in some patients receiving home parenteral nutrition (HPN) may be due to hypermanganesemia. Therefore, HPN patients and some short-term inpatients receiving TPN were studied to ascertain the relationship between dose and blood levels. METHODS: Red blood cell manganese levels were obtained by atomic absorptiometry. RESULTS: The levels in 36 hospitalized, short-term patients obtained within 48 hours of initiating TPN were all normal. The 30 patients receiving TPN from 3 to 30 days had levels that ranged from 4.8 to 28 microg/L (normal, 11 to 23 microg/L). Two patients had abnormal levels, at days 14 and 18. Fifteen of the 21 patients receiving inpatient TPN or HPN for 36 to 5075 days had elevated Mn levels. Only one patient with hypermanganesemia, an inpatient, had abnormal biochemical liver tests (bilirubin and alkaline phosphatase). One of the patients with a high level had some vestibular symptoms attributed to aminoglycoside use and had increased signal density in the globus pallidus on T1-weighted images on magnetic resonance imaging (MRI). A second patient with Mn levels twice normal had no neurologic symptoms, but had similar MRI findings. A third had some basal ganglia symptoms, confirmed by a neurologic evaluation, seizures, and very high Mn levels. The MRI showed no signal enhancement, but motion artifacts limited the study technically. CONCLUSIONS: Hypermanganesemia is seen in HPN patients receiving 500 microg manganese daily and may have resulted in some neurologic damage in three patients. Hypermanganesemia is sometimes seen after a short course of TPN in inpatients, as early as 14 days. Patients should be monitored for hypermanganesemia if they receive Mn in their TPN for >30 days. A 500 microg/d dose of Mn is probably excessive, and 100 microg/d should probably never be exceeded. Mn should be eliminated from the solution if the Mn level is elevated and should not be readministered unless the level returns to normal or subnormal. Mn should not be supplemented if the patient has liver disease with an elevated bilirubin.

Adolescent↗