Improvement of indirect immunofluorescence technique to detect antineutrophil cytoplasmic antibodies and its impact on test positivity rate

The indirect immunofluorescence (IIF) technique for antineutrophil cytoplasmic antibodies (ANCA) detection is subject to substantial differences across laboratories. This study aimed to assess the impact of improvements in the IIF-ANCA technique on the positivity rate of ANCA tests. A cross-sectional study was performed with serum samples from patients with ANCA-associated vasculitis (AAV), autoimmune hepatitis (AIH), and ulcerative colitis (UC). A paired analysis was performed for IIF-ANCA results using the traditional method and a modified protocol after a series of specific adjustments in the technique based on the protocol of IIF-ANCA test performed at a nation-wide private laboratory in Brazil. ANCA specificity was assessed by ELISA for anti-proteinase 3 (PR3) and anti-myeloperoxidase (MPO) antibodies. Sixty-one patients were evaluated. The positivity rate of IIF-ANCA tests at disease presentation performed at the University reference laboratory was 32.3% in AAV, AIH, and UC patients, whereas the positivity rates of IIF-ANCA and ELISA tests in other laboratories were 75.0 and 72.7%, respectively. After modifications in the IIF-ANCA technique, there was a significant increase in the positivity rate (14.8 vs 34.3%; P=0.0002) and in median titers [1/40 (1/30-1/160) vs 1/80 (1/40-1/80); P=0.0003] in AAV, AIH, and UC patients. UC had the highest increment in positive results from 5.3 to 36.8%. There was poor agreement between MPO- or PR3-ANCA and both IIF-ANCA techniques. In conclusion, modifications in the IIF-ANCA protocol led to a significant improvement in its positivity rate and titers.

Demographic and anthropometrical analysis and genotype distribution of chronic hepatitis C patients treated in public and private reference centers in Brazil

Hepatitis C virus (HCV) infection is a serious public health problem, since 80 percent to 85 percent of HCV carriers develop a persistent infection that can progress into liver cirrhosis and hepatocarcinoma. Considering that the response of hepatitis C patients to combination therapy with interferon and ribavirin depends on HCV characteristics as well as on host features, we made a retrospective analysis of demographic and anthropometrical data and HCV genotype distribution of chronic hepatitis C patients treated in public and private reference centers in Brazil. The medical records of 4,996 patients were reviewed, 81 percent from public and 19 percent from private institutions. Patients' median age was 46 years, and there was a higher prevalence of male (62 percent) and white patients (80 percent). The analysis of HCV-infecting strains showed a predominance of genotype 1 (64 percent) over genotypes 2 and 3. The patients' mean weight was 70.6 kg, and 65 percent of the patients weighed less than 77kg. Overweight and obesity were observed in 37.8 percent and 13.6 percent of the patients, respectively. Since a body weight of 75 kg or less has been considered an independent factor that significantly increases the odds of achieving a sustained virological response, the Brazilian population seems to have a more favorable body weight profile to achieve a sustained response than the American and European populations. The finding that 65 percent of chronic hepatitis C patients have a body weight of 77 kg or less may have a positive pharmacoeconomic impact on the treatment of genotype 1 HCV patients with weight-based doses of peginterferon.

Interferon-alpha receptor 1 mRNA expression in peripheral blood mononuclear cells is associated with response to interferon-alpha therapy of patients with chronic hepatitis C

Interferon (IFN)-alpha receptor mRNA expression in liver of patients with chronic hepatitis C has been shown to be a response to IFN-alpha therapy. The objective of the present study was to determine whether the expression of mRNA for subunit 1 of the IFN-alpha receptor (IFNAR1) in peripheral blood mononuclear cells (PBMC) is associated with the response to IFN-alpha in patients with chronic hepatitis C. Thirty patients with positive anti-HCV and HCV-RNA, and abnormal levels of alanine aminotransferase in serum were selected and treated with IFN-alpha2b for one year. Those with HBV or HIV infection, or using alcohol were not included. Thirteen discontinued the treatment and were not evaluated. The IFN-alpha response was monitored on the basis of alanine aminotransferase level and positivity for HCV-RNA in serum. IFNAR1-mRNA expression in PBMC was measured by reverse transcription-polymerase chain reaction before and during the first three months of therapy. The results are reported as IFNAR1-mRNA/á-actin-mRNA ratio (mean ñ SD). Before treatment, responder patients had significantly higher IFNAR1-mRNA expression in PBMC (0.67 ñ 0.15; N = 5; P < 0.05) compared to non-responders (0.35 ñ 0.17; N = 12) and controls (0.30 ñ 0.16; N = 9). Moreover, IFNAR1-mRNA levels were significantly reduced after 3 months of treatment in responders, whereas there were no differences in IFNAR1 expression in non-responders during IFN-alpha therapy. Basal IFNAR1-mRNA expression was not correlated with the serum level of alanine and aspartate aminotransferases or the presence of cirrhosis. The present results suggest that IFNAR1-mRNA expression in PBMC is associated with IFN-alpha response to hepatitis C and may be useful for monitoring therapy in patients with chronic hepatitis C.

In vitro-induced antibody production in chronic hepatitis C virus infection

The objectives of the present study were to assess the in vitro-induced anti-hepatitis C virus (HCV) antibody production (IVIAP) in relation to the clinical, biochemical, virologic and histologic variables of patients with HCV infection. The study included 57 patients (60 percent males) with HCV infection (anti-HCV and HCV-RNA positive). Alanine aminotransferase (ALT) was elevated in 89 percent of the patients. Mean viral load was 542,241 copies/ml and histology of the liver showed chronic hepatitis in 27/52 (52 percent) and cirrhosis in 11/52 (21 percent) patients. IVIAP levels were determined by immunoenzymatic assay at median absorbance of 0.781 at 450 nm. IVIAP was negative in 14 percent of the patients. When groups with IVIAP levels above and below the median were compared, high IVIAP levels were associated with the male sex, elevated ALT levels and more advanced disease stage. After logistic regression analysis, advanced histologic damage to the liver remained as the only independent variable associated with elevated IVIAP levels. Using a receiver operator characteristic curve, the best cut-off level for IVIAP was established (= 1.540), with 71 percent sensitivity and 94 percent specificity for the detection of more advanced disease stages (grades 3 and 4). These findings are consistent with the participation of immunological mechanisms in the genesis of the hepatic lesions induced by HCV and indicate that the IVIAP test may be useful as a noninvasive marker of liver damage either alone or in combination with other markers

Significance of the presence of antibodies against hepatitis C virus in asymptomatic blood donors

In order to determine the significance of anti-hepatitis C virus (anti-HCV) antibodies in blood donors, 46 consecutive asymptomatic individuals were recruited at the blood bank of Hospital Sao Paulo, Sao Paulo, Brazil. They were submitted to an interview to collect epidemiological data and to clinical examination and blood samples were obtained for biochemical, serological and virological analysis. All patients were followed for a minimum period of six months and those with abnormal mean alanine aminotransferase (ALT) levels were submited to a liver biopsy after giving informed consent. Hepatitis C virus RNA (HCVRNA) was detected by the polymerase chain reaction (PCR) in 22/46 (47.8 per cent) patients and this finding was associated with parenteral risk factors (P = 0.03) and ethanol abuse (P - 0.03). HCVRNA positivity was also associated with abnormal levels of ALT (P<0.001) and gamma-glutamyl transpeptidase (gamma-GT) (P=0.01). Abnormal ALT levels were a good marker of viremia, with 86.4 per cent sensitivity and 79.2 per cent specificity. Twenty-three patients with elevated mean ALT levels were submitted to a liver biopsy and histopathological changes were observed in 17 of them (73.9 per cent). HCVRNA positivity was associated with severe forms of hepatic disease (chronic hepatitis and cirrhosis). These results indicate the need for a judicious evaluation of all anti-HCV-positive blood donors, including clinical examination, biochemical tests and liver histology when ALT is persistently elevated.

Alfafetoproteína nos tumores de fígado e hepatopatias benignas / Alphafetoprotein in hepatic tumours and benign liver diseases

A alfafetoproteína (AFP) é uma proteína oncofetal que se eleva nä só no carcinoma hepatocelualr, mas também em metástases hepáticas e hepatopatias benignas. Objetivo. O conhecimento das alteraçöes de AFP, nestas doenças, facilitará a interpretaçäo dos resultados frente à suspeita de carcinoma hepatocelular. Casuística e Métodos. Os autores estudaram AFP sérica por enzima imunoensaio (Abbott, normal até 15ng/mL) em 4 grupos: 1) hepatite aguda (HA), n=24;2) hepatopatia crônio (HC), viral ou alcoólica, n = 81; 3) metástase hepática (MH), n = 29: e 4) carcinoma hepatocelular (CHC), n = 15. Resultados Observaram os seguintes resultados em percentuais de AFP menor que 15ng/mL nos 4 grupos: 75 por cento HA; 86,4 por cento HC; 79,3 por cento MH; 6,6 por cento CHC. Entre 15 e 100: HA 25 por cento; HC 8,6; MH 20,6 por cento e CHC 20 por cento. Acima de 100ng/mL: 73,3 por cento CHC e 4,9 por cento HC. Discussäo. A medida que aumentaram o limite de corte, diminuiu a sensibilidade e aumentaram a especificidade diagnóstica para hepatocarcinoma. Os resultados mostraram que a AFP se eleva em hepatopatias benignas (HA e HC) e em MH, porém, níveis acima de 100ng/mL ocorrem com muito maior freqüência no CHC apresentaram AFP elevada, possivelmente porque a doença apresentava-se em estádios avançados

Hepatite pelo vírus A em adulto: ocorrência de formas prolongadas e polifásicas da doença / Hepatitis A in adults: occurrence of prolonged and polyphasic forms of the disease

Os autores estudaram a ocorrência de formas prolongadas e/ou polifásicas da infecçao, em 84 pacientes adultos com diagnóstico de hepatite aguda pelo vírus A. Foram prolongada de doença (duraçao superior a quatro meses) foi observada em 8/84 (9,5 por cento) dos pacientes. Padrao polifásico foi observado em 12/84 (14,3 por cento) dos casos. Observou-se ainda que indivíduos com mais de 18 anos tiveram tendência a demorar mais tempo para normalizar as transaminases, quando comparados com pacientes entre 12 e 18 anos, o mesmo ocorrendo com homens, quando comparados às mulheres. Entretanto, em todos os casos observou-se normalizaçao do quadro, em períodos que chegaram a ser tao longos quanto nove a dez meses de evoluçao.

Phyllanthus amarus no tratamento da infecçäo crônica pelo vírus da hepatite B: crença ou realidade? / Phyllantus amarus in the treatment of chronic infection caused by the hepatitis B virus: belief or reality?

Estudos recentes têm demostrado eficácia do extrato de um vegetal, o Phyllanthus amarus, no tratamento dos portadores crônicos do vírus da hepatite B. Por tratar-se de substância facilmente encontrada em nosso meio e pela ausência de publicaçöes sobre seu uso para esta virose, na literatura nacional, revisäo do assunto foi realizada. Entretanto, os bons resultados referidos nao têm sido repetidos por alguns pesquisadores e, até o momento, a análise dos dados disponíveis revela controvérsias. Falhas metodológicas nesses protocolos, seja com respeito aos critérios de inclusäo, seja na discussäo dos resultados, poderiam explicar a situaçäo do problema. Conclui-se que novos estudos deveräo ser conduzidos, até que se possa estabelecer o real papel do Phyllanthus amarus no tratamento dos portadores crônicos do vírus de hepatite B.

Surto de hepatite aguda pelo vírus A: avaliaçäo epidemiológica, clínica e laboratorial / Outbreak of acute hepatitis by virus A: epidemiologic, clinical and laboratory evaluation

Os autores analisam as características epidemiológicas, clínicas e sorológicas de um surto de hepatite aguda ocorrido na cidade de Valparaiso, SP. O agente etiológico foi identificado como sendo o vírus A da hepatite e a doença incidiu sobretudo em crianças, com cerca de 80% dos casos abaixo de 10 anos de idade. Foram analisadas amostras de soro de 37 comunicante dos casos índices, sendo constatada evidência de infecçäo aguda pelo vírus A em 9/37 (24,3%) dos comunicantes, que se apresentavam totalmente assintomáticos, evidenciando a alta incidência de formas anictéricas e assintomáticas da doença

Hepatite tóxica causada por ketoconazol: relato de quatro casos / Ketoconazole causing toxic hepatitis: report of 4 cases

Säo descritos quatro casos de hepatite tóxica por ketoconazol. Todas eram mulheres e tomavam a droga de oito a 16 semanas (200mg/dia). O quadro clínico, em todas, foi superponível ao de uma hepatite viral. A normalizaçäo clínico-laboratorial ocorreu entre 60 e 90 dias após a suspensäo da droga, näo tendo havido óbito. Em uma das pacientes, o ketoconazol foi reintroduzido após normalizaçäo clínico-laboratorial, tendo ocorrido nova hepatite tóxica após 15 dias; a segunda suspensäo da droga foi seguida de cura da hepatite

Marcadores sorológicos do virus da hepatite B e anticorpo delta em homossexuais masculinos brasileiros / Serological markers for hepatitis B virus and delta antibody in Brazilian male homosexuals

Os marcadores sorológicos do vírus B da hepatite B foram estudados em um grupo de homens homossexuais em Säo Paulo, Brasil. Encontraram-se 23% de positividade para o AgHBs nos 26 homossexuais, sendo que 81% apresentavam positividade para alguns dos marcadores do vírus B. Anticorpo anti-o näo foi detectado em nenhum caso. No grupo controle, encontrou-se 1% de positividade para o AgHBs entre 500 homens estudados