Seroconversion of JCV antibodies is strongly associated to natalizumab therapy.

Previous infection with John Cunningham virus (JCV) increases the risk of progressive multifocal leukoencephalopathy in patients with multiple sclerosis (MS) undergoing treatment with natalizumab. Patients who test negative for JCV antibodies must be assessed every six months due to the risk of seroconversion. Data from the United States of America, Portugal, Holland, France, United Kingdom and Sweden have shown a strong correlation between the use of natalizumab and JCV seroconversion. The authors present now data on patients from Brazil, as there are no data from Latin American countries published on this subject yet. A group of 86 patients with MS with negative results for antibodies against JCV were included in this analyses with at least two JCV antibodies testing. Twenty-five patients (29% of the total group) did not use natalizumab at any time, while the remaining 71% used natalizumab for a median period of 800 days (equivalent to 28 monthly infusions). Seroconversion was observed in 19 patients (22.1%). There was no association of seroconversion with gender, age, previous pulses of corticosteroid or specific MS-modifying drugs. The use of natalizumab was strongly associated to seroconversion (p < 0.0001). The present results confirm the influence of natalizumab therapy on JCV antibodies in several countries and continents.

Seroconversion attributable to vaccination of heifers with the strain B-19 of Brucella abortus / Soroconversão atribuível à vacinação de bezerras com a cepa B-19 de Brucella abortus

Bovine brucellosis is transmitted by Brucella abortus and causes considerable economic losses to agribusiness. To determine the seroconversion rate attributable to vaccination of heifers with B. abortus strain B-19, 330 blood serum samples from 110 heifers aged three to eight months from five properties in the municipality of Araguaína, Tocantins, Brazil, were analyzed. On day zero (D-0), blood samples were collected, and 55 heifers from the intervention group were vaccinated. The remaining blood samples were collected on days seven (D-7), 14 (D-14), and 21 (D-21). The serum samples were analyzed using the buffered acidified plate antigen (BAPA) test. The rate of seroconversion attributable to vaccination was calculated by subtracting from the seroconversion incidence rate in the intervention group the incidence rate of the control group. On D-0, 100% (110/110) of the heifers were negative in the BAPA test (95% CI [96.70 - 100%], p 0.05) from that of heifers from the intervention group vaccinated on D-7...

A brucelose bovina é causada por Brucella abortus gerando perdas econômicas para a cadeia do agronegócio. Objetivando determinar o coeficiente de soroconversão atribuível à vacinação de bezerras com a cepa B-19 de B. abortus, foram analisadas 330 amostras de soro sanguíneo de 110 bezerras com três a oito meses de idade, provenientes de cinco propriedades do município de Araguaína/TO. O dia zero (D-0) foi marcado pela coleta de sangue dos animais do experimento seguida da vacinação das 55 bezerras do grupo intervenção. As outras coletas de sangue foram realizadas nos dias 7 (D-7), 14 (D-14) e 21 (D-21). As amostras de soro foram submetidas ao teste do antígeno acidificado tamponado (AAT). O coeficiente de soroconversão atribuível à vacinação foi calculado subtraindo-se da incidência de soroconversão no grupo intervenção àquela do grupo controle. No D-0, 100% (110/110) das bezerras amostradas não apresentaram reação ao teste do AAT (IC 95% [96,70% a 100%]; p 0,05) comparada à resposta no D-7 do grupo intervenção...

Seroconversion attributable to vaccination of heifers with the strain B-19 of Brucella abortus / Soroconversão atribuível à vacinação de bezerras com a cepa B-19 de Brucella abortus

Bovine brucellosis is transmitted by Brucella abortus and causes considerable economic losses to agribusiness. To determine the seroconversion rate attributable to vaccination of heifers with B. abortus strain B-19, 330 blood serum samples from 110 heifers aged three to eight months from five properties in the municipality of Araguaína, Tocantins, Brazil, were analyzed. On day zero (D-0), blood samples were collected, and 55 heifers from the intervention group were vaccinated. The remaining blood samples were collected on days seven (D-7), 14 (D-14), and 21 (D-21). The serum samples were analyzed using the buffered acidified plate antigen (BAPA) test. The rate of seroconversion attributable to vaccination was calculated by subtracting from the seroconversion incidence rate in the intervention group the incidence rate of the control group. On D-0, 100% (110/110) of the heifers were negative in the BAPA test (95% CI [96.70 - 100%], p < 0.05). On D-7, the seroconversion rate was 94.55% (52/55) (95% CI [84.88 - 98.84%], p < 0.05) in the intervention group and 0% (0/55) (95% CI [0.00 - 6.49%], p < 0.05) in the control group. On D-14, the rate was 98.18% (54/55) (95% CI [90.28 - 99.95%], p < 0.05) in the intervention group and 0% in the control group. Therefore, seroconversion attributable to vaccination varied from 78.39% (84.88 - 6.49%) to 92.35% (98.86 - 6.49%) on D-7 and from 83.79% (90.28 - 6.49%) to 93.46% (99.95 - 6.49%) on D-14, respectively. On D-21, the seroconversion rate in the 55 heifers from the control group vaccinated on D-14 was 100% (55/55) (95% CI [93.51 - 100%], p < 0.05) but was not significantly different (p > 0.05) from that of heifers from the intervention group vaccinated on D-7...(AU)

A brucelose bovina é causada por Brucella abortus gerando perdas econômicas para a cadeia do agronegócio. Objetivando determinar o coeficiente de soroconversão atribuível à vacinação de bezerras com a cepa B-19 de B. abortus, foram analisadas 330 amostras de soro sanguíneo de 110 bezerras com três a oito meses de idade, provenientes de cinco propriedades do município de Araguaína/TO. O dia zero (D-0) foi marcado pela coleta de sangue dos animais do experimento seguida da vacinação das 55 bezerras do grupo intervenção. As outras coletas de sangue foram realizadas nos dias 7 (D-7), 14 (D-14) e 21 (D-21). As amostras de soro foram submetidas ao teste do antígeno acidificado tamponado (AAT). O coeficiente de soroconversão atribuível à vacinação foi calculado subtraindo-se da incidência de soroconversão no grupo intervenção àquela do grupo controle. No D-0, 100% (110/110) das bezerras amostradas não apresentaram reação ao teste do AAT (IC 95% [96,70% a 100%]; p < 0,05). No D-7 a soroconversão no grupo intervenção foi de 94,55% (52/55) (IC 95% [84,88% a 98,84%]; p < 0,05) e no grupo controle foi nula (0/55) (IC 95% [0,00% a 6,49%]; p < 0,05). No D-14 a soroconversão no grupo controle continuou sendo nula e a do grupo intervenção foi de 98,18% (54/55) (IC 95% [90,28% a 99,95%]; p<0,05). Assim, a soroconversão atribuível à vacinação pode variar entre 78,39% (84,88% - 6,49%) e 92,35% (98,86% - 6,49%), e entre 83,79% (90,28% - 6,49%) e 93,46% (99,95% - 6,49%) no D-7 e D-14, respectivamente. No D-21 a soroconversão nas 55 bezerras do grupo controle vacinadas no D-14 foi de 100% (55/55) (IC 95% [93,51% a 100%]; p < 0,05), mas sem diferença significativa (p>0,05) comparada à resposta no D-7 do grupo intervenção...(AU)

Predictors of HBeAg seroconversion after long-term nucleos(t)ide analogues treatment for chronic hepatitis B: a multicenter study in real clinical setting

ABSTRACT Aims: To evaluate the HBeAg seroconversion rate in real clinical setting and explore its predictors in long-term nucleos(t)ide analogues (NAs) treatment for chronic hepatitis B (CHB). Methods: 251 patients were recruited from January 2001 to September 2009 in four hospitals in Hebei province, China, for this retrospective study. Clinical and laboratory data before and after treatment with lamivudine (LAM, 100 mg daily), adefovir (ADV, 10 mg daily), telbivudine (LDT, 600 mg daily), entecavir (ETV, 0.5 mg daily), and LAM/ADV combination were compared among three groups according to treatment outcomes: synchronous HBeAg loss and HBeAg seroconversion, anti-HBe development after treatment, and no anti-HBe. Adherence was also evaluated. Results: In real clinical setting, cumulative HBeAg seroconversion rates were 14.3%, 32.7%, 43.0%, 46.9%, and 50.5% after 1, 2, 3, 5, and 8 years, respectively. 45 patients (17.9%) were non-adherent. Adherence (p < 0.001, Hazard Ratio (HR) = 2.203), elevated alanine aminotransferase (ALT) levels (p < 0.001, HR = 2.049), and non-vertical transmission (p = 0.006, HR = 1.656) were predictors of HBeAg seroconversion. Conclusion: Adherence, elevated ALT, and non-vertical transmission are predictors of HBeAg seroconversion in CHB patients treated with NAs.

Predictors of HBeAg seroconversion after long-term nucleos(t)ide analogues treatment for chronic hepatitis B: a multicenter study in real clinical setting.

AIMS: To evaluate the HBeAg seroconversion rate in real clinical setting and explore its predictors in long-term nucleos(t)ide analogues (NAs) treatment for chronic hepatitis B (CHB). METHODS: 251 patients were recruited from January 2001 to September 2009 in four hospitals in Hebei province, China, for this retrospective study. Clinical and laboratory data before and after treatment with lamivudine (LAM, 100mg daily), adefovir (ADV, 10mg daily), telbivudine (LDT, 600mg daily), entecavir (ETV, 0.5mg daily), and LAM/ADV combination were compared among three groups according to treatment outcomes: synchronous HBeAg loss and HBeAg seroconversion, anti-HBe development after treatment, and no anti-HBe. Adherence was also evaluated. RESULTS: In real clinical setting, cumulative HBeAg seroconversion rates were 14.3%, 32.7%, 43.0%, 46.9%, and 50.5% after 1, 2, 3, 5, and 8 years, respectively. 45 patients (17.9%) were non-adherent. Adherence (p<0.001, Hazard Ratio (HR)=2.203), elevated alanine aminotransferase (ALT) levels (p<0.001, HR=2.049), and non-vertical transmission (p=0.006, HR=1.656) were predictors of HBeAg seroconversion. CONCLUSION: Adherence, elevated ALT, and non-vertical transmission are predictors of HBeAg seroconversion in CHB patients treated with NAs.