RESUMEN
BACKGROUND: Hepatitis B virus (HBV) and hepatitis D virus (HDV) represent important public health problems in the Western Amazon region with reported cases of fulminant hepatitis. This cross sectional study describes HBV and HDV genotypes circulating in the Brazilian Amazon region. METHODS: HBsAg positive individuals (n = 224) were recruited in Manaus/Amazonas State (130 blood donors from the Hematology and Hemotherapy Foundation from Amazonas/HEMOAM; 60 subjects from outpatient clinic) and in Eirunepe city (n = 34) from 2003-2009. Most participants (n = 153) lived in Manaus, 63 were from 20 remote isolated municipalities, 8 lived outside Amazonas State. Genotyping was based on PCR products: HBV genotype A-F specific primers, restricted length polymorphism for HDV. HDV isolates were directly sequenced (delta antigen 405 nucleotide fragment) and phylogenetic analysis performed (MEGA; neighbor-joining, Kimura's two parameter). RESULTS: Most participants were young adult males and HBV mono-infection predominated (70.5%, 158/224). Among blood donors, outpatient subjects and individuals from Eirunepe, HBV/A prevailed followed by HBV/D and F (p > 0.05). HBV/A was more frequent in blood donors (p < 0.05). HBV-HDV coinfection rate was 8.5% in blood donors (11/130), 65.0% (39/60) in outpatient subjects and 47.0% (16/34) in individuals from Eirunepe. Compared to blood donors, coinfection was higher in outpatient subjects (65.0% versus 8.5%; RR = 5.0; CI 3.4-7.9; p < 0.0001) and in subjects from Eirunepe (47.0% versus 8.5%; RR = 5.5; CI 3.0-9.9; p < 0.0001). HBV-HDV coinfection rates were higher in patients from highly endemic remote cities. Only HDV genotype 3 was detected, HBV/F-HDV/3 predominated (20/38; 52.7%), followed by HBV/A-HDV/3 (31.6%; 12/38) and HBV/D-HDV/3 (15.8%; 6/38). CONCLUSIONS: The description of HBV and HDV genotypes circulating in the western Amazon can contribute to a better understanding of their relevance on the regional epidemics. These infections are highly endemic in the Amazon where their control is challenged by its vast territorial dimension with small, hard-to-reach municipalities dispersed into the jungle and populated by diverse ethnic groups.
Asunto(s)
Virus de la Hepatitis B/genética , Hepatitis B/epidemiología , Hepatitis D/epidemiología , Virus de la Hepatitis Delta/genética , Adolescente , Adulto , Donantes de Sangre , Brasil/epidemiología , Coinfección/virología , Estudios Transversales , Femenino , Genotipo , Hepatitis B/microbiología , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis D/microbiología , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Polimorfismo de Longitud del Fragmento de Restricción , Adulto JovenRESUMEN
El conocimiento de las hepatitis se remonta por lo menos al siglo VIII, pero éste ha avanzado vertiginosamente en los últimos 30 años gracias a factores como la aplicación de técnicas de inmunoquímica, microscopía electrónica, estudios epidemiológicos tanto clínicos como experimentales, técnicas de ingeniería genética, etc. Este trabajo revisa aspectos históricos de estas afecciones, las lateraciones histológicas hepáticas y manifestaciones clínicas que desencadenan. También describe las características principales de los virus A, B, C y E, la respuesta inmune que produce cada uno de ellos, su forma de infectar y la evolución, complicaciones y posibilidades de prevención de la enfermedad que desencadenan. Se comentan los resultados de los tratamientos con antivirales e interferón para las infecciones crónicas por virus B y C
Asunto(s)
Humanos , Hepatitis Viral Humana/fisiopatología , Hepatitis/historia , Antivirales/administración & dosificación , Hepacivirus/patogenicidad , Hepatitis A/microbiología , Hepatitis A/fisiopatología , Virus de la Hepatitis B/patogenicidad , Hepatitis B/tratamiento farmacológico , Hepatitis B/microbiología , Hepatitis B/fisiopatología , Virus de la Hepatitis Delta/patogenicidad , Hepatitis D/microbiología , Hepatitis D/fisiopatología , Virus de la Hepatitis E/patogenicidad , Hepatitis E/microbiología , Hepatitis E/fisiopatología , Hepatovirus/patogenicidadRESUMEN
Hepatitis D virus (HDV) is the cause of an unusually severe form of liver disease with distinct histologic features (morula cell) that occurs throughout northern South America and certain other areas of the world. Clinical studies of HDV disease worldwide indicate that there is, in fact, a wide variation in pathogenesis, and the reasons for these differences are presently unknown. One possible explanation is that factors associated with the viral genotype are determinants of HDV pathogenesis. In this study, nucleic acid sequences were determined for three different northern South American HDV isolates which were obtained from individuals with severe disease or a family history of severe disease, in areas that are hyperendemic for this disease pattern. The sequences of these three isolates are very similar to one another but only distantly related to other published HDV sequences. Comparison of the sequence of a semiconserved region from a total of 14 isolates indicates that there are at least three HDV genotypes. Most published HDV sequences, including those from North America, Europe, the Middle East, the South Pacific, and Asia, belong to a single genotype which may have some geographically based subtypes. A single Japanese isolate is the sole representative of a second HDV genotype. The South American sequences reported here constitute a third genotype. The association of a particular genotype with the severe form of type D hepatitis that occurs in northern South America supports the hypothesis that HDV genetic factors are important determinants in the pathogenesis of type D hepatitis.
Asunto(s)
Virus de la Hepatitis Delta/clasificación , Virus de la Hepatitis Delta/genética , Adolescente , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Cartilla de ADN , Genotipo , Hepatitis D/microbiología , Virus de la Hepatitis Delta/aislamiento & purificación , Humanos , Italia , Japón , Masculino , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Viral/sangre , ARN Viral/aislamiento & purificación , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , América del SurRESUMEN
Contactos positivos para VD fueron investigados en un grupo de 50 sujetos masculinos, 48 homosexuales y 2 heterosexuales con antecedente de drogadicción intravenosa. Ninguno demostró presencia de anticuerpos anti-VD, mientras que el 98% y el 50% del grupo total presentó reactividad comprobada para VIH y VHB respectivamente. Es más, 19 sujetos que notificaron un número igual o superior a 5 parejas sexuales por año, presentaban uno o más marcadores del VHB, hallazgo sólo observado en 6 sujetos de 31 que notificaron menos de 5 parejas por año (p < 0.001). La no evidencia de contactos positivos para VD sugieren que el comportamiento epidemiológico de este virus es menos o no dependiente de a condición sexual de la población expuesta
Asunto(s)
Humanos , Masculino , Adulto , Anticuerpos Antivirales/análisis , Virus de la Hepatitis Delta/inmunología , Hepatitis D/microbiología , Anticuerpos Antivirales/análisis , Anticuerpos contra la Hepatitis B/análisis , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B/complicaciones , Hepatitis B/microbiología , Hepatitis D/complicaciones , Anticuerpos Anti-VIH/análisis , Factores de Riesgo , Estudios Seroepidemiológicos , Conducta Sexual , Trastornos Relacionados con SustanciasRESUMEN
Positive contacts to DV were investigated among 50 males, 48 homosexuals and 2 heterosexuals intravenously drug-addicts. None shown presence of anti-VD antibodies, while 98% and 50% from the total group demonstrated confirmed reactivity to HIV and HBV respectively. Further, 19 subjects who notified 5 or more sexual partners per year, shown one or more positive HBV markers, finding only observed in 6 subjects from 31 who notified less than 5 partners per year (p less than 0.001). The absence of DV positive contacts suggest that epidemiologically the DV seems to be loss of non-influenced by the sexual condition of the exposed population.