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J Kountouras

Publications and source records attributed to J Kountouras.

At least 19 recordsLinked to original sources
PubMed2006

Tannenbaum and metal stents in the palliative treatment of malignant distal bile duct obstruction: a comparative study of patency and cost effectiveness.

BACKGROUND: Stent clogging is the major limitation of palliative treatment for malignant biliary obstruction. Metal stents have much better patency than plastic stents, but are more expensive. Preliminary data suggest that the recently designed plastic (Tannenbaum) stent has better duration of patency than the polyethylene stent. This study aimed to compare the efficacy and cost effectiveness between the Tannenbaum stent without side holes and the uncovered metal stent for patients with malignant distal common bile duct obstruction. METHODS: In this study, 47 patients (median age, 73 years, range, 56-86 years) with inoperable malignant distal common bile duct strictures were prospectively randomized to receive either a Tannenbaum stent (n = 24) or an uncovered self-expandable metal stent (n = 23). The patients were clinically evaluated, and biochemical tests were analyzed if necessary until their death or surgery for gastric outlet obstruction. Cumulative first stent patency and patient survival were compared between the two groups. Cost-effectiveness analysis also was performed for the two study groups. RESULTS: The two groups were comparable in terms of age, gender, and diagnosis. The median first stent patency was longer in the metal group than in the Tannenbaum stent group (255 vs 123.5 days; p = 0.002). There was no significant difference in survival between the two groups. The total cost associated with the Tannenbaum stents was lower than for the metal stents (17,700 vs 30,100 euros; p = 0.001), especially for patients with liver metastases (3,000 vs 6,900 euros; p < 0.001). CONCLUSIONS: Metal stent placement is an effective treatment for inoperable malignant distal common bile duct obstruction, but Tannenbaum stent placement is a cost-saving strategy, as compared with metal stent placement, especially for patients with liver metastases and expected short survival time.

Aged↗
PubMed2006

Endoloop-assisted polypectomy for large pedunculated colorectal polyps.

BACKGROUND: The use of an endoloop may minimize the risk for bleeding after endoscopic polypectomy of large colorectal polyps. This study aimed to assess the safety and efficacy of colonoscopic ligation of the stalk of large pedunculated polyps by means of an endoloop technique, and to focus particular attention on the instances in which the use of this device was unsuccessful. METHODS: This study retrospectively evaluated attempted endoloop endoscopic polypectomy in 33 patients (19 men and 14 women; mean age, 62.5 years) with large pedunculated polyps. RESULTS: Application of the endoloop was impossible in four patients, and the snare became entangled with the loop in one patient. The remaining 28 patients underwent endoloop-assisted polypectomy. Bleeding occurred in four patients, either because the loop slipped of the stalk after polypectomy (2 patients) or because a thin stalk (< or = 4 mm) was transected by the loop before polypectomy (2 patients). CONCLUSION: Colonoscopic polypectomy with an endoloop may be safer than conventional polypectomy. The reasons for technical failure of this technique include a narrow left colon lumen, a thin stalk (< or = 4 mm), and close cutting in relation to the site of encirclement by the loop.

Adult↗
PubMed2006

Rheumatic-like syndrome as a symptom of underlying gastric cancer.

Several observations imply that atypical rheumatic manifestations may be associated with occult neoplasia. A 71-year-old woman was admitted to the hospital three times in 2 years. Initially, she was admitted for investigation of an iron-deficient anemia associated with upper intestinal tract symptoms. Endoscopy revealed hiatus hernia, esophagitis, and duodenal ulcer with a Helicobacter pylori infection, but there were no signs of malignancy, and the patient received appropriate drug treatment. Two years later, she presented with arthralgias concerning the upper and lower limbs in an asymmetrical distribution, low fever, and persistence of the anemia, despite the treatment she had received and the fact that her gastrointestinal symptoms had long ceased. Immunological assays showed no specific rheumatic disorder, and the patient was discharged after showing significant improvement with the use of COX-2 selective NSAIDs. Finally, 4 months later, she was readmitted with worsening of the arthralgias, arthritis in the right radiocarpal joint, and severe anemia. Hematemesis that occurred during her hospital stay led to an emergency endoscopy and the diagnosis of gastric adenocarcinoma. Only a few cases have been reported so far concerning rheumatic manifestations as signs of an occult gastric cancer. Thus, there must be some degree of suspicion when dealing with patients with anemia and rheumatic symptoms that cannot be classified into a particular rheumatologic entity, because they might conceal a gastrointestinal malignancy not yet evident.

Adenocarcinoma↗
PubMed2006

Relationship between Helicobacter pylori infection and Alzheimer disease.

The authors investigated the association between Helicobacter pylori infection (Hp-I) and Alzheimer disease (AD) by using histology for diagnosis of Hp-I. Fifty patients with AD and 30 iron deficiency anemic control participants without AD were included. The histologic prevalence of Hp-I was 88% in patients with AD and 46.7% in controls (p < 0.001).

Adult↗
PubMed2006

Safety and long-term follow-up of endoscopic snare excision of ampullary adenomas.

BACKGROUND: Adenomas of the duodenal papilla are rare. Because of their malignant potential, resection is mandatory. Options for resection include endoscopic resection techniques, transduodenal local excision, and pancreaticoduodenectomy. The aim of this retrospective study was to evaluate the safety and outcome of endoscopic snare resection of papillary adenomas in a Greek cohort of patients. METHODS: Fourteen patients (six women and eight men; age range, 42-76 years) were referred for endoscopic management of ampullary adenomas. A questionnaire was completed for each patient, which included preoperative and postoperative data points. Presenting symptoms were jaundice (n = 4), cholangitis (n = 1), and pain (n = 2). Seven patients were asymptomatic. If there was no common bile and main pancreatic duct invasion and the appearance suggested a benign lesion, biductal sphincterotomy onto normal duodenal tissue was performed. The adenomas were resected via a diathermy snare, along with the major papilla, after elevation of the lesion by epinephrine plus dextrose 50% (1:10,000) solution. At the discretion of the endoscopist, a biliary or pancreatic stent was inserted as a prophylactic procedure immediately after excision. RESULTS: Histopathologically, resected tissue included 11 adenomas and three adenomas with focal malignancy, referred for pancreaticoduodenectomy. Immediate complications were moderate bleeding (n = 1) and mild pancreatitis (n = 1). No procedure-related death occurred. Follow-up was available for 11 patients (mean, 28.36 months; range, 6-72). Pancreatic and biliary stents were placed in four and nine patients, respectively. Follow-up endoscopy revealed recurrent/residual adenomatous tissue in two patients (18%), which was resected endoscopically. CONCLUSION: Endoscopic snare resection of adenomas of the major duodenal papilla is a safe, well-tolerated alternative to surgical therapy. In expert hands, complications are mild and may be avoided by pre-resection biductal sphincterotomy, stent placement, and elevation of the lesion by epinephrine plus dextrose 50% solution injection.

Adenoma↗
PubMed2005

Association between Helicobacter pylori infection and acute inflammatory demyelinating polyradiculoneuropathy.

The aim of this study was to investigate a possible association between Helicobacter pylori infection and acute inflammatory demyelinating polyradiculoneuropathy (AIDP). Of 17 consecutive patients with Guillain-Barre syndrome (GBS), 13 patients (six females; mean age 50 +/- 24 years) with AIDP were investigated. Clinical status was evaluated according to Hughes' score, and electrophysiological tests were performed within 2 weeks from disease onset. Helicobacter pylori infection was detected histologically and serum H. pylori-specific IgG antibodies were analysed by ELISA. Twenty asymptomatic patients (12 females; mean age 63 +/- 8 years), undergoing upper gastrointestinal endoscopy for investigation of mild iron deficiency anaemia, served as controls. Helicobacter pylori was found in 12 of 13 AIDP patients (92%), and in 10 of 20 controls (50%), (P = 0.02). Electrophysiological studies showed demyelination in all AIDP patients. High levels of anti-H. pylori IgG antibodies correlated with advanced clinical status. Five of seven AIDP patients with high levels of anti-H. pylori IgG antibodies had delayed F-wave latencies, indicating affection of proximal segments of peripheral nerves. Helicobacter pylori infection seems to be more frequent in AIDP patients. Anti-H. pylori titre might reflect advanced clinical status. Anti-H. pylori IgG antibodies are also associated with involvement of the proximal parts of peripheral nerves in AIDP.

Adolescent↗
PubMed2003

Apoptosis in hepatitis C.

The apoptotic process appears to be a host defence mechanism against viral infections and tumourigenesis. However, many viral genomes encode proteins, which repress apoptosis so as to escape from immune attack by the host. Therefore, virus-host interactions may determine viral persistence, extent and severity of liver inflammation and possibly viral hepatocarcinogenesis. Apoptosis of liver cells may play a significant role in the pathogenesis of hepatitis C. Pathomorphologic features of increased apoptosis include shrinkage and fragmentation of nuclei/cytoplasm in piecemeal necrosis areas, acidophilic bodies, and focal cell dropout in the liver lobule. The hepatitis C virus (HCV) core protein exhibits both proapoptotic or antiapoptotic actions. Modulation of apoptosis may involve binding of HCV core protein to the intracellular signal transducing portion of death receptors and displacement of signalling molecules. Apoptosis may occur in the absence of significant transaminase elevation, thereby explaining the lack of correlation between biochemical activity and liver cell histological injury. Monitoring caspase activation might provide a reliable tool to estimate the efficacy of HCV therapy, and might open challenging therapeutic strategies in HCV infection. The antiviral effect of interferon may be mediated through induction of apoptosis. Lastly, administration of the antiapoptotic ursodeoxycholic acid in HCV infection is compatible with the notion that apoptosis may represent a mechanism for viral shedding rather than for viral elimination, thereby raising the concept that inhibition of apoptosis could ameliorate hepatitis C.

Antiviral Agents↗
PubMed2003

Methylene blue chromoendoscopy for the detection of Barrett's esophagus in a Greek cohort.

BACKGROUND AND STUDY AIMS: Specialized columnar epithelium of Barrett's esophagus is a precursor of dysplasia and adenocarcinoma, and methylene blue selectively stains this type of epithelium. The present prospective study examined the detection of short-segment and long-segment Barrett's esophagus using methylene blue chromoendoscopy-directed biopsies, in comparison with biopsies directed using conventional endoscopic criteria. PATIENTS AND METHODS: Biopsies were obtained from macroscopically conspicous areas in the distal esophagus observed during conventional endoscopy in a total of 975 patients. Immediately after conventional biopsies, the distal esophagus was sprayed with methylene blue and directed biopsies were then obtained from the stained regions. All patients with a histologically established Barrett's esophagus underwent a second upper gastrointestinal endoscopy within 1 year in order to assess the reproducibility of the method. RESULTS: In a total of 3,900 conventional biopsy specimens (without staining), 54 specimens (1.4%) were found to show Barrett's esophagus and were confined to 16 of the 975 patients (1.6%). Of the total 130 directed biopsy specimens obtained during chromoendoscopy, 114 (87.7%) revealed Barrett's esophagus (P<0.00001) and were confined to 35 of the 975 patients (3.5%; P < or = 0.001). The findings were confirmed within 1 year in all dye-positive patients. CONCLUSIONS: Chromoendoscopy with methylene blue appears to be an accurate, simple, safe, inexpensive, and reproducible method of detecting specialized columnar epithelium in Barrett's esophagus.

Adolescent↗
PubMed2001

Relationship between Helicobacter pylori infection and glaucoma.

OBJECTIVE: To determine the frequency of Helicobacter pylori (H. pylori) infection in glaucoma patients and in anemic control participants. DESIGN: Prospective, nonrandomized, comparative study. PARTICIPANTS: The authors investigated 32 patients with chronic open-angle glaucoma (COAG), 9 patients with pseudoexfoliation glaucoma (PEG), and 30 age-matched anemic control participants. METHODS: Upper gastrointestinal endoscopy was performed to evaluate macroscopic abnormalities, and gastric mucosal biopsy specimens were obtained for the presence of H. pylori infection tested by rapid urease slide test (CLO test) and by Cresyl fast violet staining, Giemsa staining, or both. The presence of gastritis was classified in accordance with the Sydney system by using hematoxylin and eosin stain. In addition, intestinal metaplasia was evaluated with Alcian blue stain. Saliva samples were also tested by CLO. Serum was analyzed for the presence of H. pylori-specific IgG antibodies by enzyme-linked immunosorbent assay. MAIN OUTCOME MEASURE: Histologic examination for the presence of H. pylori. RESULTS: In 87.5% of the COAG patients, 88.9% of the PEG patients, and 46.7% of the anemic control participants, H. pylori infection was histologically confirmed (odds ratio, 8.00; chi-square, 11.81; P = 0.0006 and 9.14; chi-square, 5.01; P = 0.02, respectively). H. pylori was detected by urease test: (1) in the gastric mucosa in 71.9% of the COAG patients, in 77.8% of the PEG patients, and in 46.7% of the anemic control participants (P = 0.03 and P > 0.05, respectively); and (2) in the saliva in 37.5% of the COAG patients, in 55.6% of the PEG patients, and in 30% of the anemic control participants (P > 0.05). Sixty-eight percent of glaucoma patients and 30% of anemic control participants were seropositive for H. pylori (P = 0.002). When compared with anemic control participants, glaucoma patients exhibited less often endoscopic normal appearance of gastric mucosa (P = 0.01), and more often antral gastritis (P = 0.0004) or peptic ulcer disease (P = 0.01). Histologic grade 3 gastritis was observed only in the glaucoma patients (P = 0.03). CONCLUSIONS: H. pylori infection seems more frequent in glaucoma patients. If confirmed, this may indicate either a common factor that causes susceptibilities to both glaucoma and H. pylori infection or that H. pylori may be a causal factor for developing glaucoma.

Adult↗
PubMed1999

Antigenic stimulation in T-cell cultures in cardiomyopathies: differences in cytokine profiles.

Immune-mediated mechanisms are involved in the pathogenesis of cardiomyopathies. In this study, we investigate which pattern of immune response (Th1 or Th2) lies behind these diseases by analysing the basic cytokines secreted from PHA-cultured T lymphocytes and determining what differences, if any, exist between dilated cardiomyopathy (DMC) and hypertrophic cardiomyopathy (HCM). Two groups of patients were studied: 10 patients with DCM and 10 patients with HCM. Age- and sex-matched healthy individuals were used as controls. PHA-cultured T lymphocytes in the presence or absence of different myocardial antigen (MA) concentrations were measured. Interleukine-2 (IL-2), Interleukine-6 (IL-6) and Interferon-gamma (IFN-gamma) levels were measured in culture supernatants by an ELISA method. At the same time, delayed-type hyperactivity (DTH) against the same antigenic preparation was measured by the leukocyte migration inhibitory index technique. Patients were subdivided into DTH-positive and DTH-negative and re-examined for IL-2 cytokine expression. IL-6 levels were found to increase both in the presence and in the absence of MA in the patient groups compared to the controls. IL-2 levels were decreased in both groups, in an antigen dose-related manner. Anergic patients showed a further reduction in IL-2 levels for both groups of patients. IFN-gamma remained unaffected in the patient groups. Almost half of the patients exhibited anergy to the DTH reaction against MA. We conclude that, upon antigenic stimulation, the initially mounted immune response (increased IL-6) is somehow blocked/switched off in patients, resulting in an immunologic tolerance/unresponsiveness to MA (IL-2 decreased, IFN-gamma unchanged). Finally, increased IL-6 could lead to a perpetuation of immunologic injury through the release of oxygen-free radicals with a cytotoxic effect on the myocardium. We hypothesize an antigen-related, defective macrophage-Th1 cell reaction, which accounts for the differences in the IL-2 profile between the DCM and HCM groups, that might cause local immune responses to lead to immunosuppression (immune tolerance effect), thus contributing to the pathogenesis of cardiomyopathies.

Adult↗
PubMed1996

The effect of mannitol and secretin on the biliary transport of urate in humans.

No evidence is available on the transport of biliary urate and the possible role of choleretic agents in the regulation of biliary urate elimination in humans. To test this hypothesis we studied the following: (1) 45 cholecystomized patients to determine urate levels in hepatic bile and gallbladder bile, and (2) 13 cholecystomized patients fitted with T-tubes to determine the effects of secretin injection (either 70 U of porcine secretin or 0.02 mg.kg-1 of synthetic human secretin, as a single dose) and/or mannitol infusion (5 cm3.min-1 for 90 minutes) on biliary urate excretion. In the latter group, samples of bile and serum were analyzed for urate under basal state and after the administration of both agents. In our first approach, results showed that urate concentrations present in hepatic as well as in gallbladder bile were much lower than the corresponding values in serum (P < .001). The mean gallbladder bile urate concentration was not significantly increased over the concentration in hepatic bile. When compared with basal state values, procine and synthetic secretin induced a significant increase in mean urate clearance (P < .001) because of a significant increase in mean bile flow (P < .001), whereas the mean biliary urate concentration significantly decreased (P < .001) with a concomitant decrease in the mean serum urate concentration (P < .02). Mannitol also induced a significant increase in the mean urate clearance (P < .002) because of a significant increase in the mean biliary urate concentration (P < .01) with a concomitant decrease in the mean serum urate concentration (P < .01) and without changes in the mean bile flow (P > .05). Therefore, it appears that a substantial amount of urate is eliminated by biliary route. The load of biliary urate excreted may be modified by mannitol and secretin and possibly other factors, a finding that could have an application in some pathological conditions associated with decreased renal urate excretion.

Adult↗