Amanda Alves Fecury

Clinical and pathological importance of vacA allele heterogeneity and cagA status in peptic ulcer disease in patients from North Brazil.

We have examined the prevalence of gene cagA and vacA alleles in 129 patients, 69 with gastritis and 60 with peptic ulcer diseases from North Brazil and their relation with histopathological data. vacA and cagA genotype were determined by polymerase chain reaction. Hematoxylin-eosin staining was used for histological diagnosis. 96.6% of the patients were colonized by Helicobacter pylori strains harboring single vacA genotype (nont-mixed infection). Among them, 11.8% had subtype s1a, 67.8% had subtype s1b, and 17% subtype s2. In regard to the middle region analysis, m1 alleles were found in 75.4% and m2 in 21.2% of patients. The cagA gene was detected in 78% patients infected with H. pylori and was associated with the s1-m1 vacA genotype. The H. pylori strains, vacA s1b m1/cagA-positive, were associated with increased risk of peptic ulcer disease and higher amounts of lymphocytic and neutrophilic infiltrates and the presence of intestinal metaplasia. These findings show that cagA and vacA genotyping may have clinical relevance in Brazil.

Hepatitis B and C virus infection among Brazilian Amazon riparians

INTRODUCTION Viral hepatitis is a major public health concern in Brazil. There are few past studies on this issue, especially among riparian communities. This study aims at determining the seroprevalence of viral hepatitis B and C in the riparian community of Pacuí Island, within the Cametá municipality of Pará State, Brazil. Moreover, this study aims to investigate the principal risk factors that this community is exposed to. METHODS The current study has accessed blood samples from 181 volunteers who have answered an epidemiological questionnaire. Analyses on serological markers have been tested with commercial ELISA kits for detecting HBsAg, total anti-HBc, anti-HBs, and anti-HCV. Within seroreactive patients for HCV, RT-PCR and line probe assay have been performed to identify the viral genotype. RESULTS In the serological marker analysis for hepatitis B, no reactivity for HBsAg, rate of 1.1% for total anti-HBc, and rate of 19.3% for anti-HBs have been observed. On hepatitis C, 8.8% seroprevalence has been found, in which 62.5% have gotten viral RNA. Among the risk factors studied, the following have been highlighted: non-use of condoms, sharing of cutting instruments, use of illicit drugs, and reports of family disease with HBV or HCV. CONCLUSIONS The vaccination coverage against HBV is low, and the high prevalence of HCV within this community has been observed.

ROLE OF HELICOBACTER PYLORI INFECTION AND LIFESTYLE HABITS IN THE DEVELOPMENT OF GASTRODUODENAL DISEASES IN A POPULATION FROM THE BRAZILIAN AMAZON

CONTEXT Although more than half of the worlds population is colonized with Helicobacter pylori, it remains unknown why this organism is able to produce severe disease in some hosts and be innocuous in others. The clinical outcome of infection is determined by several factors, including differences in the host response to bacterial stimulation, specific virulence factors of the organism and environmental influences, or a combination of these factors. OBJECTIVES This study compared the prevalence of H. pylori infection and risk factors (infection with CagA+ strains, excessive alcohol consumption, smoking, and inadequate eating habits) between patients with different gastrointestinal disorders and associated these risk factors with the histopathological findings. METHODS In a prospective study, samples were collected from 442 patients and a standardized questionnaire regarding lifestyle habits (excessive alcohol consumption, smoking, and eating habits) was applied. The presence of H. pylori and of the cagA gene was investigated by polymerase chain reaction (PCR). Gastric biopsies were obtained for histological assessment. RESULTS The frequency of alcohol consumption, smoking, inadequate diet and infection with CagA+ H. pylori was higher among patients with peptic ulcer and adenocarcinoma when compared to those with gastritis. Gastric inflammation was more pronounced in patients infected with CagA+ strains. CONCLUSION We conclude that infection with CagA+ H. pylori strains, excessive alcohol consumption, smoking and inadequate eating habits increase the risk of developing peptic ulcer and gastric carcinoma.

Prevalence of viral hepatitis B and C in riverside communities of the Tucuruí Dam, Pará, Brazil

Epidemiologically, the relevance of infection caused by hepatitis viruses is related mainly to their wide geographic distribution and the large number of infected individuals in all parts of the world. In this study, 668 residents from the islands around the Tucuruí Dam were selected. Blood samples were collected for investigation of serological markers (HBsAg, total anti‐HBc, anti‐HBS, and anti‐HCV) by enzyme immunoassays. HCV‐positive subjects were tested using RT‐PCR and RFLP for the identification of viral genotypes. Among the 668 subjects studied, 1.9% were HBsAg positive, 28% were total anti‐HBc positive, and 41.9% were anti‐HBs positive. The anti‐HBs marker alone (vaccine response) was detected in 25.7% of the volunteers. Anti‐HCV antibody was detected in 2.2% of the subjects and genotype 1 was the predominant genotype (70%). The results indicate an intermediate level of HBV and HCV endemicity in the region studied, as well as low HBV vaccination coverage. J. Med. Virol. 84:1907–1912, 2012.

Differences in virulence markers between Helicobacter pylori strains from the Brazilian Amazon region

INTRODUCTION This study compares virulence markers of Helicobacter pylori isolated from patients in 2 cities in the Brazilian Amazon. METHODS The study analyzed 168 patients with chronic gastritis from Belém and 151 from Bragança, State of Pará, Brazil. Levels of bacterial DNA associated with cagA and vacA alleles were checked by PCR, and hematoxylin-eosin staining was used for histologic diagnosis. RESULTS In Bragança 87% of patients were genotype s1m1 cagA-positive (s1m1 cagA+), compared with 76% in Belém. In samples from patients in both cities, there was an association between s1m1 cagA+ strains and gastric mucosal damage. CONCLUSIONS Both cities have a high frequency of s1m1 cagA+ strains of H. pylori.

Prevalence of hepatitis C virus infection and genotypes in patient with chronic kidney disease undergoing hemodialysis

The prevalence of antibodies to HCV varies among Brazilian regions at rates of 8–16%. Since this virus is transmitted by the parenteral route through blood and blood products, patients receiving maintenance hemodialysis therapy are at an increased risk of infection. The study was conducted in seven dialysis centers in Belém, Pará, northern Brazil. Blood samples were collected from 798 patients with chronic renal disease treated by hemodialysis. The samples were tested for antibodies against HCV and the viral genotype was identified. Sixty‐seven (8.4%) of the 798 patients studied were anti‐HCV positive by ELISA, ranging from 4% to 14% in different centers. Viral RNA was detected in 5.3% (43/798) of the patients; of these, 42 also had anti‐HCV antibodies. HCV genotyping revealed genotype 1 as the most common, detected in 86.1% (37/43) of the patients, followed by genotype 2 in 11.6% (5/43) and genotype 3 in one patient (2.3%). The findings of this study highlight the importance of control strategies for hepatitis C in hemodialysis patients. Molecular biology methods need to be available in these centers to screen for HCV on admission in order to establish effective infection control measures. J Med. Virol. 85:1741–1745, 2013.

Association between histological findings, aminotransferase levels and viral genotype in chronic hepatitis C infection

INTRODUCTION The genomic heterogeneity of hepatitis C virus (HCV) influences liver disorders. This study aimed to determine the prevalence of HCV genotypes and to investigate the influence of these genotypes on disease progression. METHODS Blood samples and liver biopsies were collected from HCV-seropositive patients for serological analysis, biochemical marker measurements, HCV genotyping and histopathological evaluation. RESULTS Hepatitis C virus-ribonucleic acid (HCV-RNA) was detected in 107 patients (90.6% with genotype 1 and 9.4% with genotype 3). Patients infected with genotype 1 exhibited higher mean necroinflammatory activity and fibrosis. CONCLUSIONS HCV genotype 1 was the most prevalent and was associated with greater liver dysfunction.

Evaluation of the Pattern of EPIYA Motifs in the Helicobacter pylori cagA Gene of Patients with Gastritis and Gastric Adenocarcinoma from the Brazilian Amazon Region

The Helicobacter pylori is associated with the development of different diseases. The clinical outcome of infection may be associated with the cagA bacterial genotype. The aim of this study was to determine the EPIYA patterns of strains isolated from patients with gastritis and gastric adenocarcinoma and correlate these patterns with the histopathological features. Gastric biopsy samples were selected from 384 patients infected with H. pylori, including 194 with chronic gastritis and 190 with gastric adenocarcinoma. The presence of the cagA gene and the EPIYA motif was determined by PCR. The cagA gene was more prevalent in patients with gastric cancer and was associated with a higher degree of inflammation, neutrophil activity, and development of intestinal metaplasia. The number of EPIYA-C repeats showed a significant association with an increased risk of gastric carcinoma (OR = 3.79, 95% CI = 1.92–7.46, and P = 0.002). A larger number of EPIYA-C motifs were also associated with intestinal metaplasia. In the present study, infection with H. pylori strains harboring more than one EPIYA-C motif in the cagA gene was associated with the development of intestinal metaplasia and gastric adenocarcinoma but not with neutrophil activity or degree of inflammation.

ANALYSIS OF POLYMORPHISMS IN THE INTERLEUKIN 18 GENE PROMOTOR (-137 G/C AND -607 C/A) IN PATIENTS INFECTED WITH HEPATITIS C VIRUS FROM THE BRAZILIAN AMAZON

BACKGROUND The hepatitis C virus has been recognized as the leading cause of chronic liver disease in the world. Host genetic factors have been implicated in the persistence of hepatitis C virus infection. Single nucleotide polymorphisms at positions -607 C/A (rs1946518) and -137 G/C (rs187238) in the IL-18 gene promoter have been suggested to be associated with delayed hepatitis C virus clearance and persistence of the disease. OBJECTIVE Identify these polymorphisms in a population infected with hepatitis C virus from the Brazilian Amazon region. METHODS In a cross-sectional analytical study conducted in Belém, Pará, Brazil, 304 patients infected with hepatitis C virus were divided into two groups: group A, patients with persistent infection; group B, patients with spontaneous clearance. The control group consisted of 376 volunteers not infected with hepatitis C virus. Samples were analyzed by RT-PCR for the detection of viral RNA and by RFLP-PCR to evaluate the presence of the -137 G/C and -607 C/A IL-18 gene promoter polymorphisms. RESULTS Comparison of polymorphism allele frequencies between the patient and control groups showed a higher frequency of allele C at position -607 among patients (P=0.02). When the association between the polymorphisms and viral infection was analyzed, patients carrying genotype C/A at position -607 were found to be at higher risk of persistent hepatitis C virus infection (P=0.03). CONCLUSION The present results suggest a possible role of the -607 IL-18 gene promoter polymorphism in the pathogenesis of hepatitis C virus infection.