Fecal occult blood test has been utilized to screen for lower gastrointestinal pathologies, such as colorectal cancer and polyps that bleed. Recent studies have revealed a relatively high frequency ...of upper gastrointestinal abnormalities in subjects with positive fecal occult blood by guaiac-based method. Although immunohistochemical tests of fecal occult blood were assumed to have greater diagnostic validity, the distribution of gastrointestinal pathology using such examinations is not well established. This study aims to investigate the efficacy of immunohistochemical analysis of fecal occult blood in detecting upper and lower gastrointestinal lesions in asymptomatic individuals.
Subjects who underwent regular health checkups were enrolled if they received both esophagogastroscopic and colonoscopic examinations. Each subject was tested by an immunohistochemical fecal occult blood test. The fecal occult blood results were evaluated and correlated with lesions identified in endoscopic examinations.
In total 655 males and 722 females with age 46.2 +/- 12.1 years were enrolled, 287 cases (20.7%) had polypoid lesions of colon, including 6 colon cancers, 37 with polyps > or = 1 cm, 104 with polyp 5-9 mm, and 140 with polyp < 5 mm. FOB was positive in 31 cases, of which 15 (15/31, 48.4%) were polypoid lesions of colon, 1 was colonic ulcer, 9 (29.0%) were active gastroduodenal ulcers but 6 (19.4%) had no significant lesions. The positive and negative predictive value for colon polyps was 48.4% and 80%, respectively. The sensitivity was 50% (3/6) for colon cancer and varied among polyps with different sizes: 16.2% (6/37) for polyps > or = 1 cm; 5.8% (6/104) for polyps 5-9 mm and 0% (0/140) for polyps < 5 mm.
A substantial portion of subjects (29%) with positive fecal occult blood reaction of immunohistochemical analysis but negative colonoscopy still needs esophagogastroscopic examination to disclose upper gastrointestinal lesions. Immunohistochemical determination of fecal occult blood remains imperfect for polypoid lesions of colon in view of its sensitivity and specificity.
Hepatitis C viral infection in 125 hemodialysis patients from Taiwan was studied using a second-generation anti-HCV immunoassay (EIA II) (Abbott HCV 2.0 EIA) and the polymerase chain reaction (PCR) ...to detect the HCV RNA in the serum. A total of 59 patients (47.2%) were positive by EIA II. In comparison, the conventional C100-3 anti-HCV assay was positive in 40 (32.0%). HCV RNA was found in 47 patients (37.6%). Patients with elevated serum transaminase level had a higher positive rate of anti-HCV and HCV RNA. The dialysis time was longer for those patients positive for anti-HCV than for those who were negative. A total of 57 of the 59 EIA II-positive cases had a history of blood transfusion. The HBsAg status did not influence the anti-HCV positivity. Among the 59 EIA II-positive patients, 66.1% were also positive for HCV RNA, and of the 47 HCV RNA-positive cases 83.0% were positive for EIA II. It is concluded that the high prevalence of specific HCV infection and HCV viremia was present in these patients. Prevention of cross-contamination during dialysis and blood screening before transfusion are important for the control of HCV infection in these patients.
Twenty patients with chronic hepatitis C virus (HCV) infection and acute exacerbations (group A) were studied by polymerase chain reaction with genotype-specific primers to explore the role of mixed ...infections of HCV in acute exacerbations of chronic type C hepatitis. Another 26 patients who did not have acute exacerbation were matched controls (group B). Eleven (55%) of the group A patients had heterologous HCV, and their mean age was significantly younger than that of the 9 without heterologous infection (55 vs. 67 years, P < .05). In contrast, only 2 group B patients (7.7%) had heterologous HCV infection. In 10 of 13 patients with heterologous HCV infection, type III/2a virus emerged on type II/1b HCV, and viral interference was observed in half of them. The results support that mixed infections of HCV may be important in acute exacerbations of chronic type C hepatitis.
Icteric type hepatocellular carcinoma is rare, and a poor prognosis has been demonstrated in the past. We performed this study to re-evaluate prognosis since the availability of modern diagnostic ...modalities. Of 3921 patients with hepatocellular carcinoma in our hospital, 9 patients who presented with tumor fragments in common bile duct and had a patent portal vein were submitted for analysis. Cholangiocarcinoma was suspected in 7 patients before the study was completed, and icteric type hepatocellular carcinoma was diagnosed in all 9 patients after serial studies that included serum alpha-fetoprotein levels, computed tomography, angiography, and histology. The prognosis was better in the 4 resectable patients (survival time 16, 31, 33, and 63 months, respectively), and was extremely poor for the 5 patients who received palliative treatment only (mean survival time, 4.5 months). Because of the apparently discrepant outcomes, this specific type of hepatocellular carcinoma should be kept in mind in areas where hepatocellular carcinomas are prevalent, and the suspected cases should be thoroughly investigated, because prognosis may be improved when resection is done at an earlier stage.
ABSTRACT
Previous data on the association of Helicobacter pylori infection with gastric cancer by demographic or histological features are inconsistent due to a univariate analysis of limited case ...numbers. The aim of the present study was to determine such an association by the use of a large series of patients and multiple variables analysis. The serum IgG antibodies against H. pylori were measured in 397 patients with histologically verified gastric cancer. A multiple logistic regression analysis was used to define the association between seropositivity and demographic or tumour characteristics of gastric cancer. The overall seropositivity of H. pylori was 63%. In univariate analysis, the prevalence was significantly lower among patients with cardia (50%) or diffuse‐type (56.6%) cancers than those with non‐cardia (64.8%) or intestinal‐type (70.3%) cancer (P<0.05 and P<0.01, respectively). There was no statistical difference between H. pylori infection rate and gender, age or tumour stage. A multiple logistic regression analysis showed tumour location and histology remained significant factors associated with seropositivity of H. pylori with an odds ratio of approximately 2.0. Analysis of combined histology and location revealed that patients with intestinal‐type cancer at non‐cardia locations had the highest odds ratio of 3.93 (95% confidence interval (CI): 1.55–10.0) compared with the lowest odds ratio of 0.69 (95% CI: 0.30–1.62) in diffuse cardia cancer (P< 0.005). Our data indicate H. pylori infection in gastric cancer is independently affected by the histological subtype and by tumour location.
Sera of 40 patients with posttransfusion non-A, non-B hepatitis were tested for hepatitis C and B viral genomes by polymerase chain reaction and for hepatitis C antibodies by synthetic peptide ...immunoassays. Five were then considered to have chronic hepatitis before transfusion. Six patients without hepatitis C markers and hepatitis B virus DNA recovered. In 29 recipients who became positive for hepatitis C virus RNA, posttransfusion hepatitis C was diagnosed. Of them, 5 were hepatitis B surface antigen carriers. Synthetic peptide immunoassays detected 28 whereas anti-C100 assay detected 23 of the 29 acute hepatitis C patients. Anticapsid antibody appeared earlier than the antinonstructural antibody in 10 seroconverters. They appeared simultaneously in 15 seroconverters but anticapsid antibody appeared later then the antinonstructural antibody in 3 hepatitis B carriers. Transient suppression of hepatitis B surface antigenemia was found in 2, whereas elevated hepatitis B virus DNA was found in 3 carriers during acute hepatitis C superinfection. In 2 carriers whose hepatitis C became chronic, both hepatitis B and C viral genomes persisted throughout 2 years of followup. Therefore these assays define posttransfusion hepatitis C more precisely, and there seems no significant interference between chronic hepatitis B and C virus infections.
The status of genetic instability was determined with seven microsatellite markers from 40 patients with primary gastric adenocarcinoma. For those cases with microsatellite instability, alterations ...of hMSH2 were further investigated by direct sequencing of reverse transcription-polymerase chain reaction products. Twelve (30%) of 40 patients were found to have microsatellite instability. Among them, one patient (
1
6
, 16.7%) was early gastric cancer and 11 (
11
34
, 32.4%) were advanced gastric cancer. There were seven patients with diffuse type (
7
18
, 38.7%), while five (
5
22
, 22.7%) were intestinal type tumors. The entire coding region of the hMSH2 gene in these 12 affected individuals was amplified and sequenced. Only a 41-year-old female patient with diffuse type advanced gastric cancer showed a GCT to TCT missense mutation at codon 207 with predicted protein change from alanine to serine. Our results indicate that genetic instability plays an important role in gastric tumorigenesis and alterations of the hMSH2 gene are related to only a small portion of sporadic gastric adenocarcinoma with microsatellite instability.
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