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R Paraná

Publications and source records attributed to R Paraná.

At least 19 recordsLinked to original sources

HCV infection in northeastern Brazil: unexpected high prevalence of genotype 3a and absence of African genotypes.

The genomic diversity of HCV embraces 6 genotypes and at least 52 subtypes with clinical and epidemiological correlations. There is a paucity of studies assessing HCV genotypes and biomolecular epidemiology in Brazil. We studied genotype distribution and epidemiological aspects in 232 HCV carriers, 133 (57.9%) males and 99 (42.1%) females, followed in the liver disease referral unit in Salvador, BA, northeastern Brazil. All of them were anti-HCV positive by 3rd generation ELISA assay, and HCV-RNA positive by RT-PCR. Genotyping was performed by INNOLIPA. Assessment of risk factors for HCV infection showed that 93 (40%) had past blood transfusion, 14 (6%) intravenous drug use, 19 (8%) inhalation of cocaine, 28 (12%) tattooing, 15 (7%) were health care workers, 5 (2%) had reused disposable syringes, 5 (2%) had multiple risk factors and in 53 (23%) no risk factor was determined. Genotype 1a was observed in 75 (32%), 1b in 72 (31%), 3a in 61 (26%), 2ab in 14 (6%); 5 (2.5%) had mixed genotypes and 5 (2.5%) were undetermined. Patients with genotype 1 had a higher mean age (P < 0.05) and no particular risk factors were associated with a specific genotype. Genotype 1 largely predominates in northeast Brazil followed by genotype 3 which, in this population, does not seem to be related to intravenous drug abuse, in contrast to some European studies. Although 80% of the Salvador population comprises African-Brazilians, no African genotype was identified, which may mean that HCV was introduced into this region via European immigration. This study demonstrated some peculiarities of HCV epidemiology in Brazil and strongly suggests that HCV introduction to this region was probably related to European immigration.

Adult↗

Schistosomiasis mansoni and viral B hepatitis in woodchucks.

BACKGROUND/AIMS: An interaction between human schistosomiasis and viral hepatitis B has often been suggested, but never established. The experimental investigation has been hampered by the lack of a suitable model. Only woodchucks are susceptible to both Schistosoma mansoni and a B-like hepatitis virus (WHV) infections. This study explores the relevance of this unique model regarding hepatitis/schistosomiasis interactions. METHODS: Woodchucks (Marmota monax and Marmota marmota) were infected with: (a), S. mansoni; (b), WHV; or (c), both S. mansoni and WHV. RESULTS: Following the experimental parasitic infection of woodchucks, with or without WHV, schistosomiasis presented a peculiar and severe course in early infection, involving mostly the intestines. Subsequently, the intestinal and hepatic lesions underwent considerable modulation and the periovular granulomas decreased in size and number, while the parasitic infection tended to self-cure within the 9 months following infection. Nine woodchucks inoculated with the hepatitis virus alone presented with several degrees of acute and chronic hepatitis, with one of them dying of hepatocarcinoma 1 year after inoculation. Four woodchucks with concomitant viral and schistosome infections presented with a simple additive pattern of lesions, without any evidence of modification or aggravation of either one of the two infections. Similarly, no significant impact of schistosomiasis on WHV serum markers could be seen. CONCLUSIONS: Schistosomiasis and viral hepatitis in woodchucks run parallel courses, with neither apparent special histological features derived from the association of the two conditions, nor modulation of WHV replication. Schistosomiasis itself, however, was observed to run a peculiar course in the woodchuck. The present data are important for consideration in further experiments exploring the interplay between schistosomiasis and viral hepatitis induced liver damage in this unique experimental host.

Animals↗

Effect of interferon-alpha on experimental septal fibrosis of the liver - study with a new model.

Interferon-alpha is used in antiviral therapy in humans, mainly for viral hepatitis B and C. An anti-fibrotic effect of interferon has been postulated even in the absence of anti-viral response, which suggests that interferon directly inhibits fibrogenesis. Rats infected with the helminth Capillaria hepatica regularly develop diffuse septal fibrosis of the liver, which terminates in cirrhosis 40 days after inoculation. The aim of this study was to test the anti-fibrotic effect of interferon in this experimental model. Evaluation of fibrosis was made by three separate methods: semi-quantitative histology, computerized morphometry and hydroxyproline measurements. Treatment with interferon-alpha proved to inhibit the development of fibrosis in this model, especially when doses of 500,000 and 800,000 IU were used for 60 days. Besides confirming the anti-fibrotic potential of interferon-alpha on a non-viral new experimental model of hepatic fibrosis, a clear-cut dose-dependent effect was observed.

Animals↗

Comparative study of bacterial infection prevalence between cirrhotic patients with and without upper gastrointestinal bleeding.

Bacterial infection is a frequent complication in patients with chronic liver disease, mainly during the advanced stages. There is evidence that the main factors that contribute to a predisposition to infection in cirrhotic patients are related to hepatic failure with consequent immunodeficiency. Invasive procedures (diagnostic or therapeutic) can predispose to bacterial infections, and upper gastrointestinal bleeding (UGB) is considered a potentially important risk factor. A group of cirrhotic patients (child B and C Pugh groups) were evaluated retrospectively by chart reviews regarding the prevalence of bacterial infection during hospitalization to determine whether UGB was a risk factor. An infection was considered present if a specific organ system was identified or if fever (> 38(o)C) persisted for more than 24 hours with associated leukocytosis. Spontaneous bacterial peritonitis was based on classical criteria. Eighty-nine patients were evaluated. Fourty-six patients presented with UGB, and 43 patients had no UGB (control). There were infections recorded in 25/46 (54%) patients with UGB, and 15/43 (35%) in those without UGB (p=0.065). The ratio of the number of infections/admitted patients, was significantly larger in the group with UGB (0.78 +/- 0.89 vs. 0.39 +/- 0.62; p=0.028) since patients had more than one infection. In the UGB group compared to non UGB group, ascites was more frequent (67% vs. 42%; p=0.027); they were more likely to have undergone endoscopic procedures (p<0.001) and the mean +/- SD for platelets count was smaller (96,114 +/- 57,563 vs 145,674 +/- 104,083; p=0.007). The results show that UGB is an important contribution to bacterial infection among Child B and C cirrhotic patients.

Bacterial Infections↗

Subacute thyroiditis during treatment with combination therapy (interferon plus ribavirin) for hepatitis C virus.

Autoimmune thyroiditis has been frequently reported during interferon monotherapy for hepatitis C, but there are few reports concerning subacute thyroiditis. Recently, combination therapy of IFN plus ribavirin has become the preferred therapeutic schedule for chronic hepatitis C. Similarly to interferon monotherapy, there are no reports concerning subacute thyroiditis during combination therapy. We described four episodes of subacute thyroiditis occurring in three patients during antiviral combination therapy. All patients had symptoms compatible with hyperthyroidism, which could be misdiagnosed as IFN side-effects. The antiviral treatment was continued in all three patients and thyroid function increased progressively with pharmacological treatment for hyperthyroidism. We concluded that subacute thyroiditis may be a complication of combination antiviral therapy and should be investigated in patients presenting with compatible symptoms, in order to differentiate from IFN side-effects.

Adult↗

Severe strongyloidiasis during interferon plus ribavirin therapy for chronic HCV infection.

Ribavirin is a nucleoside analogue, recently introduced in hepatitis C virus (HCV) therapy, that has postulated immunomodulatory and immunosuppressive action. Strongyloidiasis is an helmintic infection caused by Strongyloides stercoralis, endemic in tropical countries. Severe strongyloidiasis has been demonstrated after immunosuppression by corticosteroids evolving some fatal cases. Here, we describe two cases of severe strongyloidiasis coincident with ribavirin plus interferon therapy for treating HCV infection. The review of our monotherapy protocol with interferon did not disclose any case of symptomatic strongyloidiasis pointing to a possible role of ribavirin in modifying immune response to S. stercoralis. We propose a careful screening for S. stercoralis before initiating ribavirin therapy or even empiric antihelmintic treatment.

Adult↗

Hepatic capillariasis in rats: a new model for testing antifibrotic drugs.

Rats infected with the helminth Capillaria hepatica regularly develop septal hepatic fibrosis that may progress to cirrhosis in a relatively short time. Because of such characteristics, this experimental model was selected for testing drugs exhibiting antifibrosis potential, such as pentoxifylline, gadolinium chloride and vitamin A. Hepatic fibrosis was qualitatively and quantitatively evaluated in liver samples obtained by partial hepatectomy and at autopsy. The material was submitted to histological, biochemical and morphometric methods. A statistically significant reduction of fibrosis was obtained with pentoxifylline when administered intraperitoneally rather than intravenously. Gadolinium chloride showed moderate activity when administered prophylactically (before fibrosis had started), but showed a poor effect when fibrosis was well advanced. No modification of fibrosis was seen after vitamin A administration. Hydroxyproline content was correlated with morphometric measurements. The model appears to be adequate, since few animals die of the infection, fibrosis develops regularly in all animals, and the effects of different antifibrotic drugs and administration protocols can be easily detected.

Animals↗

Hepatitis C virus genotypes in a northeastern area of Brazil.

We used a reverse transcription-polymerase chain reaction (RT-PCR) to obtain the genotypes of circulating hepatitis C virus (HCV) in patients from a Gastro-Hepatology Unit in the city of Salvador (Bahia State) in northeastern Brazil. Viral RNA was detected in 83 (65.4%) of 127 anti-HCV seropositive serum samples. Positivity was significantly associated with alterations in levels of aspartate aminotransferase and alanine aminotransferase (P < 0.05). Genotyping of HCV was performed by RT-PCR using genotype-specific primers from the core region: 24.1% were infected with subtype 1a, 38.6% with 1b, 3.6% with 2, 21.7% with 3a, and 12.0% with a mixed genotype. There was no difference in genotype distribution when compared with results from other Brazilian locations. Surprisingly, the high frequency of genotype 3 in Brazilian samples continues to be different from that reported around the world and warrants further investigation.

Adolescent↗

New hepatitis viruses.

Three new hepatitis viruses are reviewed; Hepatitis E Virus (HEV), Hepatitis G Virus (HGV), and Transfusion Transmitted Virus (TTV). Only HEV has been clearly associated with liver damage. It is transmitted by the fecal-oral route and tends to occur in poor socio-economic conditions. Acute disease is diagnosed by the presence of anti-HEV IgM antibodies in the serum. Hepatitis G virus and TTV are transmitted parenterally. HGV is the same agent as GBV-C. Although it is hepatotropic, and high levels of viremia may occur, pathogenicity to the liver has not been proven. TTV may also be transmitted by the fecal-oral route. It is abundant in liver tissue but, like HGV, pathogenicity has not been proven.

DNA Virus Infections↗

Thyroid disease in HCV carriers undergoing antiviral therapy with interferon plus ribavirin.

High prevalence of thyroid autoantibodies, with or without overt thyroiditis, has been described in hepatitis C patients, particularly in those undergoing alpha-interferon treatment. The aim of this study was to describe the frequency and clinical outcome of thyroid disease in a cohort of HCV carriers before and during combination therapy with interferon plus ribavirin. Between May, 1997, and May, 1999, 111 previously untreated (naive) patients were treated with a-interferon plus ribavirin for 6 or 12 months. Of those, 67 (60%) patients were male and 44 (40%) female. Thyroid function was evaluated in all patients by testing free T4, TSH and antiTPO within 30 days prior to treatment, 90 days after treatment was initiated, and 6 months after treatment was concluded. Abnormal thyroid tests were observed in 4 (3.6%) patients--1 male and 3 female--before the onset of antiviral treatment. Three patients were already undergoing T4 replacement due to Hashimoto thyroiditis and 1 patient had positive antiTPO with normal free T4 and TSH. All 4 patients completed the treatment regime for HCV, but required hormone replacement. Among the patients with a normal thyroid function test prior to treatment (107 cases), 5 (4.6%) developed thyroid test abnormalities; 2 patients had hypothyroidism due to autoimmune thyroiditis; 1 patient became positive for antiTPO antibodies but thyroid function remained normal, and 2 patients had subacute thyroiditis. Four of these patients (80%) were female and 1 was male (20%). A family history of thyroid disease was strongly predictive of thyroid abnormalities during antiviral treatment. In conclusion, there is a low prevalence of thyroid function abnormalities in HCV carriers with no prior antiviral treatment. Family history of thyroid disease reinforces the special attention to thyroid abnormality development before considering antiviral therapy. Subacute thyroiditis during combination therapy was observed, but its pathogenesis is still unknown. Evaluation of thyroid function during and after antiviral treatment is strongly recommended because thyroid related symptoms can be easily misinterpreted as medication side effects.

Adult↗

Acute sporadic non-A, non-B hepatitis in Northeastern Brazil: etiology and natural history.

In a 4-year follow-up study, patients with acute sporadic non-A, non-B (NANB) hepatitis were evaluated to determine the etiology and natural history of the disease. Acute hepatitis C virus (HCV) was detected in 13 of 43 (30%) of patients, anti-hepatitis E virus (HEV) IgG in 5 (12%), and 25 (58%) were considered non-A-E. The HCV RNA was detected in all HCV patients but none of the non-A-E cases. The initial clinical and biochemical presentation of the HCV and non-A-E cases was quite similar, although 2 of the non-A-E patients had severe disease. The 5 patients who were found to be anti-HEV IgG-reactive recovered within 6 months of follow-up. Of the 13 HCV cases, alanine transaminase (ALT) levels returned to normal in 7 (53. 8%), while 6 (46.2%) continued to show abnormal ALT after 6 months of follow-up. However, 9 (69.2%) of them remained HCV-RNA-positive, denoting virological/biochemical dissociation. Long-term follow-up showed a reappearance of HCV RNA in 2 of the 4 patients who were in virological remission performing 84% of chronicity rate. Acute non-A-E hepatitis patients were less likely to evolve toward chronicity, as compared with acute HCV cases (16% vs. 84%; P =.0001). Only 4 (16%) of the non-A-E patients were hepatitis G virus (HGV)-RNA-positive. Concerning risk factors for acquiring parenterally transmitted viruses, tattooing was the only one that could be associated with HCV transmission (P =.002). No risk factors could be identified for putative non-A-E virus transmission. Liver biopsies performed for chronic HCV patients showed a variable degree of inflammation, while the non-A-E patients presented less severe histological disease.

Acute Disease↗

[Antibodies to hepatitis C virus in patients undergoing hemodialysis in Salvador, BA, Brazil].

BACKGROUND: Hepatitis C infection in hemodialysis units has been evaluated in different geographic regions. AIMS: The prevalence of anti-HCV in patients undergoing hemodialysis program in the city of Salvador, State of Bahia, Brazil, was studied and its association with transfusions, duration of hemodialysis and ALT elevation. METHOD: During a period of 17 months, all patients undergoing dialytic treatment, were evaluated. The total number of patients was 395, all of whom completed a questionnaire and provided serum samples for laboratory analysis. Serological levels were measured for ALT and the samples were tested for anti-HCV using ELISA II with a further confirmation using RIBA III. RESULTS: Anti-HCV was positive in 23.8% (94/395). The presence of transfusions was associated with anti-HCV and as the number of transfusions used increased, so did the frequency of anti-HCV. Of the patients who never received transfusions, 12.5% (6/48) were anti-HCV positive. The duration of dialytic treatment lasted from 53.44 +/- 36.45 months in the anti-HCV positive group and 22.10 +/- 22.75 months for the group testing negative. ALT elevation was more frequent in the anti-HCV positive group. Positivity for the RIBA III fractions was 79.8%, 100%, 80.9% and 52.1%, for c100-3, c33, c22 and NS5, respectively. The anti-NS5 was even less frequent in the group with elevated ALT. CONCLUSIONS: The prevalence of anti-HCV in patients undergoing chronic hemodialysis in Salvador, Bahia, is elevated and it is associated with transfusions, a longer duration of dialytic treatment and ALT elevation.

Adolescent↗

Fulminant hepatitis with microvesicular steatosis (a histologic comparison of cases occurring in Brazil--Labrea hepatitis--and in central Africa--Bangui hepatitis).

A similar histopathologic picture of fatal hepatitis associated with widespread acute fatty changes in hepatocytes and single-cell necrosis was seen in epidemic cases occurring in two distinct equatorial areas having high prevalences of HBV and HDV infections. The cases were previously considered to be two different entities; Labrea hepatitis in Brazil, and Bangui hepatitis in the Central African Republic. However, the histopathologic findings suggest that they are pathogenetically and etiologically related to HBV and HDV infections, probably modified by some as yet unknown factor(s) present in equatorial forest zones.

Adolescent↗