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1.
Rev. chil. infectol ; 33(6): 635-649, dic. 2016. tab
Artigo em Espanhol | LILACS | ID: biblio-844417

RESUMO

In this article the present recommendations for immunization of adult patients who received hematopoietic stem cell transplantation -a common procedure in therapy of many types of hematological diseases and serious inborn defects of the immune system- are reviewed and discussed. Patients that undergo this kind of transplantation procedure exhibit, compared to the general population, an elevated susceptibility of immune-preventable infections, due to loss of the humoral and cellular protective immunity. A revaccination strategy for transplanted patients can result in a significant diminution of morbidity and mortality related to the treatment of these diseases. Few data are published about the duration and magnitude of the vaccination response in this specific population of patients. Moreover, deviation from international guidelines recommendations for post-transplant immune prophylaxis can be observed frequently, partly as a result of the absence of specific vaccines in some countries. Multiple factors as intensity of the pharmacologic immune suppression, myeloablative regimen, administration of monoclonal and polyclonal antibodies, duration of the post-transplant period or the presence of graft-versus-host disease (GVHD), can influence the immune response and establish special considerations for certain biological agents, as observed in case of living attenuated virus composed vaccines. This conditions are responsible for the fact that an optimal time point for vaccination of transplanted patients remains not clearly defined. More specific studies about the underlying immunological mechanisms during immunocompromised periods are necessary to understand better the immunogenicity and security of existing vaccines. The development of innovative vaccines as well can induce certain advances in the post-transplant therapy.


El presente artículo revisa las recomendaciones actuales para la inmunización de pacientes adultos que han recibido trasplante de células madre hematopoyéticas, procedimiento común en la terapia de muchas patologías hematológicas y defectos congénitos del sistema inmune. Los pacientes que reciben este tipo de tratamiento son más susceptibles a infecciones inmunoprevenibles que la población general debido a la pérdida de la inmunidad protectora tanto humoral como celular con posterioridad al trasplante. De esta manera, la revacunación de los receptores de trasplante representa una estrategia importante para reducir la morbilidad y mortalidad asociadas con esas enfermedades. Sin embargo, se conoce poco sobre la duración y magnitud de la respuesta inmunológica generada por las vacunas en esta población. Además, aunque existen guías internacionales consensuadas en inmunoprofilaxis post-trasplante, frecuentemente ocurren desviaciones en las prácticas recomendadas por múltiples motivos, incluyendo la no disponibilidad de ciertas vacunas en algunos sistemas de salud. Factores como la intensidad de la inmunosupresión farmacológica, el régimen mieloablativo empleado, la administración de anticuerpos monoclonales y policlonales, la duración de la fase neutropénica en el período posterior al trasplante y la presencia de enfermedad injerto versus hospedero (graft-versus-host disease, GVHD) pueden influenciar la respuesta inmunitaria y establecer consideraciones especiales para ciertos agentes como es el caso de las vacunas compuestas por virus vivos atenuados. Estas condiciones contribuyen a que el momento oportuno de inicio de las inmunizaciones en los receptores de trasplante aún no se encuentre bien definido. Se requieren más estudios específicos acerca de los mecanismos inmunológicos subyacentes durante los estados de inmunocompromiso para entender mejor la inmunogenicidad y seguridad de las vacunas existentes en dichos contextos. El desarrollo de vacunas innovadoras puede también inducir avances en la terapia post-trasplante.


Assuntos
Humanos , Feminino , Adulto , Vacinas Bacterianas/administração & dosagem , Vacinas Virais/administração & dosagem , Esquemas de Imunização , Vacinação/métodos , Transplante de Células-Tronco Hematopoéticas , Costa Rica
2.
Rev Chilena Infectol ; 33(6): 635-649, 2016 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-28146188

RESUMO

In this article the present recommendations for immunization of adult patients who received hematopoietic stem cell transplantation -a common procedure in therapy of many types of hematological diseases and serious inborn defects of the immune system- are reviewed and discussed. Patients that undergo this kind of transplantation procedure exhibit, compared to the general population, an elevated susceptibility of immune-preventable infections, due to loss of the humoral and cellular protective immunity. A revaccination strategy for transplanted patients can result in a significant diminution of morbidity and mortality related to the treatment of these diseases. Few data are published about the duration and magnitude of the vaccination response in this specific population of patients. Moreover, deviation from international guidelines recommendations for post-transplant immune prophylaxis can be observed frequently, partly as a result of the absence of specific vaccines in some countries. Multiple factors as intensity of the pharmacologic immune suppression, myeloablative regimen, administration of monoclonal and polyclonal antibodies, duration of the post-transplant period or the presence of graft-versus-host disease (GVHD), can influence the immune response and establish special considerations for certain biological agents, as observed in case of living attenuated virus composed vaccines. This conditions are responsible for the fact that an optimal time point for vaccination of transplanted patients remains not clearly defined. More specific studies about the underlying immunological mechanisms during immunocompromised periods are necessary to understand better the immunogenicity and security of existing vaccines. The development of innovative vaccines as well can induce certain advances in the post-transplant therapy.


Assuntos
Vacinas Bacterianas/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Esquemas de Imunização , Vacinação/métodos , Vacinas Virais/administração & dosagem , Adulto , Costa Rica , Feminino , Humanos
3.
Cancer Epidemiol Biomarkers Prev ; 18(5): 1631-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19423538

RESUMO

Driven by findings that human papillomavirus (HPV)-induced degradation of p53 differs by a TP53 polymorphism at codon 72 (Pro72Arg), past studies of TP53 genetic variants and cervical cancer have focused on this nonsynonymous polymorphism, with mixed results. We analyzed common single nucleotide polymorphisms (SNP) across the TP53 locus in a population-based nested case-control study in Guanacaste, Costa Rica. We evaluated 11 SNPs, including Pro72Arg (rs1042522), among 1,281 women: 465 with cervical intraepithelial neoplasia grade 3/cancer (CIN3+), 380 with HPV persistence (median, 25 months), and 436 random population controls. We combined HPV persistence and CIN3+ into one case group because they did not differ in TP53 genotypic frequencies and calculated odds ratios and 95% confidence intervals (CI) for individual SNPs and inferred haplotypes. We observed that proline at codon 72 was associated with increased risk of CIN3+/persistence compared with population controls. Relative to GG (Arg), the CG (Pro/Arg) and CC (Pro) genotypes had a 1.3-fold (95% CI, 0.99-1.6) and 1.8-fold (95% CI, 1.2-2.7) increased risk, respectively (P(trend) < 0.01). rs12951053 and rs1642785 were also associated with CIN3+/persistence (P (trend), 0.05 and 0.04, respectively), as was a haplotype containing the codon 72 variant (rs1042522), rs12951053, rs1642785, and rs12947788 (odds ratio, 1.6; 95% CI, 1.1-2.3 versus the most common haplotype, which comprised the major alleles for all 11 SNPs). Although genetic variation in TP53 might affect the natural history of HPV and cervical cancer, further work is needed to elucidate the possible mechanism.


Assuntos
Variação Genética , Papillomaviridae/genética , Infecções por Papillomavirus/genética , Polimorfismo de Nucleotídeo Único , Proteína Supressora de Tumor p53/genética , Displasia do Colo do Útero/genética , Adulto , Alelos , Estudos de Casos e Controles , Códon , Costa Rica , Progressão da Doença , Feminino , Genótipo , Humanos , Modelos Logísticos , Risco
4.
J Infect Dis ; 199(1): 20-30, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19012493

RESUMO

BACKGROUND: We examined host genetic factors to identify those more common in individuals whose human papillomavirus (HPV) infections were most likely to persist and progress to cervical intraepithelial neoplasia grade 3 (CIN3) and cancer. METHODS: We genotyped 92 single-nucleotide polymorphisms (SNPs) from 49 candidate immune response and DNA repair genes obtained from 469 women with CIN3 or cancer, 390 women with persistent HPV infections (median duration, 25 months), and 452 random control subjects from the 10,049-woman Guanacaste Costa Rica Natural History Study. We calculated odds ratios and 95% confidence intervals (CIs) for the association of SNP and haplotypes in women with CIN3 or cancer and HPV persistence, compared with random control subjects. RESULTS: A SNP in the Fanconi anemia complementation group A gene (FANCA) (G501S) was associated with increased risk of CIN3 or cancer. The AG and GG genotypes had a 1.3-fold (95% CI, 0.95-1.8-fold) and 1.7-fold (95% CI, 1.1-2.6-fold) increased risk for CIN3 or cancer, respectively (P(trend) = .008; referent, AA). The FANCA haplotype that included G501S also conferred increased risk of CIN3 or cancer, as did a different haplotype that included 2 other FANCA SNPs (G809A and T266A). A SNP in the innate immune gene IRF3 (S427T) was associated with increased risk for HPV persistence (P(trend) = .009). CONCLUSIONS: Our results require replication but support the role of FANCA variants in cervical cancer susceptibility and of IRF3 in HPV persistence.


Assuntos
Reparo do DNA/genética , Infecções por Papillomavirus/epidemiologia , Polimorfismo de Nucleotídeo Único , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/genética , Estudos de Coortes , Costa Rica/epidemiologia , Sondas de DNA de HPV , DNA Viral/isolamento & purificação , Proteínas de Ligação a DNA/genética , Progressão da Doença , Exodesoxirribonucleases/genética , Proteína do Grupo de Complementação A da Anemia de Fanconi/genética , Feminino , Genes BRCA1 , Genes BRCA2 , Humanos , NADPH Oxidases/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/fisiopatologia , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
5.
J Clin Microbiol ; 45(5): 1447-54, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17344361

RESUMO

The objective of this analysis was to compare the performance characteristics of two human papillomavirus (HPV) DNA detections assays, the Hybrid Capture 2 assay (HC2) and the SPF(10) assay, for the detection of carcinogenic HPV. Data are from the enrollment visits of women who participated in the randomized, double-blind, placebo-controlled phase III HPV16/18 Vaccine Trial in Guanacaste, Costa Rica. We compared the results of HC2 and SPF(10) testing of cervical specimens. Since the line probe assay (LiPA) detection system does not distinguish between HPV type 68 (HPV68; which is targeted by HC2) and HPV73 (which is not targeted by HC2), for SPF(10)-LiPA, we defined the carcinogenic HPV types as the 12 HC2-targeted types (types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59), HPV68/73, and the HC2-cross-reactive, carcinogenic type HPV66. The kappa values and the performance characteristics for the detection of cervical abnormalities were ascertained. Paired observations were available for 5,683 sexually active, young women (median age, 21 years). The prevalence of carcinogenic HPV types was 35% (n=1,962) by HC2 and 35% (n=2,003) by SPF(10)-LiPA. There were no differences in the prevalence of carcinogenic HPV types by HC2 and SPF(10)-LiPA among women with normal, atypical squamous cells of undetermined significance and high-grade squamous intraepithelial lesion cytology. Among women with low-grade squamous intraepithelial lesion cytology, HC2 was more likely to test positive than SPF(10)-LiPA for the carcinogenic HPV types (87% and 79%, respectively; P=0.001) as a result of HC2 cross-reactivity with HPV types 40, 43, 44, 53, 54, 60, 70, and 74. The crude agreement between the two assays was 88%, with a kappa value of 0.75 (95% confidence limits, 0.73 to 0.76). We observed very good agreement between HC2 and SPF(10)-LiPA for carcinogenic HPV type detection.


Assuntos
DNA Viral/isolamento & purificação , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Hibridização de Ácido Nucleico/métodos , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Costa Rica/epidemiologia , Feminino , Genótipo , Humanos , Infecções por Papillomavirus/epidemiologia , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/epidemiologia
6.
Cancer Res ; 66(20): 10112-9, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17047075

RESUMO

Persistent cervical infections with carcinogenic human papillomaviruses (HPV) cause virtually all cervical cancer. Cytologic abnormalities are the manifestations of HPV infections used to identify women at risk. To compare the potential of the full range of anogenital HPV genotypes to induce cytopathic effects, we examined the influences of HPV type, viral load, and age on cytopathology among 1,222 women having a single HPV type at enrollment into a 10,000-woman population-based study in Costa Rica. Cervical specimens were tested for approximately 40 HPV types by MY09/MY11 L1 primer PCR and type-specific dot blot hybridization. Types were organized by phylogenetic species and cancer risk. PCR signal strength served as a qualitative surrogate for viral load. Overall, 24.8% [95% confidence interval (95% CI), 22.4-27.3] of single prevalent HPV infections had concurrent abnormalities (atypical squamous cells or worse) ranging from 0.0% to 80.0% based on HPV type. Noncarcinogenic alpha3/alpha15 types, although highly prevalent, uncommonly caused cytologic abnormalities (13.1%; 95% CI, 9.8-17.0). In contrast, one quarter to nearly one half of infections with a single major carcinogenic species type (alpha9/alpha11/alpha7/alpha5/alpha6) produced abnormalities. Greater abnormalities were observed with increasing qualitative viral load of carcinogenic types; fewer abnormalities were observed among older women (>54 years). A high percentage (46.2%) of detected abnormalities in women infected with HPV16 or related alpha9 types were high grade or worse, consistent with strong carcinogenicity, compared with 10.7% in women infected with alpha7 types, including HPV18, a major cause of adenocarcinoma. The lack of evident severe abnormalities associated with HPV18 and related HPV types might have implications for screening for poorly detected glandular and alpha7-related lesions.


Assuntos
Papillomaviridae/classificação , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Doenças do Colo do Útero/patologia , Doenças do Colo do Útero/virologia , Adulto , Fatores Etários , Colo do Útero/patologia , Colo do Útero/virologia , Estudos de Coortes , Costa Rica/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Doenças do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Carga Viral , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
7.
Cancer Res ; 66(2): 1218-24, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16424061

RESUMO

Approximately 15 human papillomavirus (HPV) types cause virtually all cervical cancer whereas other HPV types are unrelated to cancer. We were interested in whether some noncarcinogenic types differ from carcinogenic in their affinity for the cervical transformation zone, where nearly all HPV-induced cancers occur. To examine this possibility, we tested cervical specimens from 8,374 women without cervical precancer and cancer participating in a population-based study in Guanacaste for >40 HPV types using PCR. We compared age-group specific prevalences of HPV types of the alpha9 species, which are mainly carcinogenic and include HPV16, to the genetically distinct types of the alpha3/alpha15 species (e.g., HPV71), which are noncarcinogenic and common in vaginal specimens from hysterectomized women. We related HPV detection of each group to the location of the junction between the squamous epithelium of the ectocervix and vagina and the columnar epithelium of the endocervical canal. Models evaluated the independent effects of amount of exposed columnar epithelium (ectopy) and age on the presence of alpha9 or alpha3/alpha15 types. Prevalence of alpha9 types (7.6%) peaked in the youngest women, declined in middle-aged women, and then increased slightly in older women. By contrast, prevalence of alpha3/alpha15 types (7.6%) tended to remain invariant or to increase with increasing age. Detection of alpha9 infections increased (P(trend) < 0.0005) but alpha3/alpha15 infections decreased (P(trend) < 0.0005) with increasing exposure of the columnar epithelia. Older age and decreasing cervical ectopy were independently positively associated with having an alpha3/alpha15 infection compared with having an alpha9 infection. These patterns need to be confirmed in other studies and populations. We suggest that these genetically distinct groups of HPV types may differ in tissue preferences, which may contribute to their differences in carcinogenic potential.


Assuntos
Papillomaviridae/genética , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/virologia , Adulto , Fatores Etários , Idoso , Transformação Celular Neoplásica , Costa Rica/epidemiologia , DNA Viral/análise , Estudos Epidemiológicos , Feminino , Humanos , Histerectomia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Lesões Pré-Cancerosas , Prevalência , Vagina/virologia
8.
Tissue Antigens ; 66(4): 321-4, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16185329

RESUMO

Human leukocyte antigen (HLA) variations may affect immune response to human papillomavirus infection and subsequent cervical neoplasia risk. We investigated the frequency and relationship between HLA-A-B and HLA-A-B-DR haplotypes among women with cervical cancer/high-grade lesions (n=365) and cytologically normal population controls (n=681) within three cervical neoplasia studies in the US and Costa Rica. Notable differences in haplotype frequencies were observed; the HLA-A*01-B*08 haplotype occurred in >5% of US Caucasians but in <1% of Costa Ricans. The most prevalent HLA-A*24-B*40-DR*04 haplotype in Costa Rica (5%) was found in <1% of US Caucasians. No HLA haplotype was significantly associated with cervical neoplasia, suggesting that individual allele associations reported to date (e.g. HLA-DR*13) are not likely explained by underlying haplotypes.


Assuntos
Antígenos HLA/genética , Haplótipos/genética , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Costa Rica , Feminino , Predisposição Genética para Doença/genética , Antígenos HLA/imunologia , Haplótipos/imunologia , Humanos , Papillomaviridae/imunologia , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/imunologia , Fatores de Risco , Estados Unidos , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/imunologia , Displasia do Colo do Útero/virologia
9.
J Infect Dis ; 191(11): 1796-807, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15871111

RESUMO

BACKGROUND: Detailed epidemiologic studies of cervical type-specific human papillomavirus (HPV) infection in large populations are scarce. METHODS: We recruited a population-based cohort in Guanacaste, Costa Rica. Participants were interviewed, screened for cervical neoplasia, and tested for >40 HPV types by use of MY09/11 L1 consensus primer polymerase chain reaction. We estimated the risk factors for infection and the associations between type-specific HPV infections and cervical intraepithelial neoplasia (CIN) and cancer in 8514 sexually active women who had not undergone a hysterectomy. RESULTS: The overall HPV prevalence was 26.5%. The most common type was HPV-16 (3.6% of the population). HPV prevalence showed a U-shaped age-specific curve. Sexual behaviors were the main determinants of oncogenic and nononcogenic infections; age at first sexual intercourse was not independently associated with infection. Barrier contraceptive use was somewhat protective against infection. Oncogenic infections were strongly associated with risk of all grades of CIN and of cancer. Types 16, 18, and 58 were the most common in women diagnosed with CIN3 and cancer. Except for those that included HPV-16, multiple-type infections were associated with an increased risk (compared with that for single-type infections) of all grades of CIN and of cancer. CONCLUSIONS: We confirmed the bimodal age pattern of HPV infection in Guanacaste and the sexually transmitted nature of both oncogenic and nononcogenic HPV types.


Assuntos
Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto , Fatores Etários , Idoso , Costa Rica/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Papillomaviridae/classificação , Infecções por Papillomavirus/complicações , Prevalência , Fatores de Risco , Neoplasias do Colo do Útero/virologia
10.
J Infect Dis ; 191(11): 1808-16, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15871112

RESUMO

BACKGROUND: Cross-sectional human papillomavirus (HPV) DNA prevalence peaks at young ages, reflecting sexual acquisition and typically rapid clearance. In some populations, HPV prevalence demonstrates a second peak in older women. Longitudinal data may help to explain this second peak. METHODS: We followed a population-based cohort of 7237 women in Guanacaste, Costa Rica, in which we had previously observed a second peak in the baseline HPV prevalence in older women. We tested for >40 HPV types by polymerase chain reaction. We analyzed age-specific patterns of acquisition and persistence 5-7 years after enrollment for individual HPV types. RESULTS: At enrollment and follow-up, cross-sectional data revealed U-shaped age-specific HPV prevalence curves for virtually every type, with higher prevalences in the younger and older women than in the middle-aged women. Prospectively, acquisition of types decreased significantly as women aged (PTrend<.05, for both), with the highest peak in young women and a secondary minor peak in older women. Type-specific persistence of HPV increased with age (PTrend<.0001). Overall, HPV acquisition predominated at younger ages, whereas persistent infections gradually became more prominent with age (PTrend<.0001). CONCLUSIONS: Newly apparent infections decreased, whereas persistence increased, with age; this latter tendency supports the utility of HPV screening in older women.


Assuntos
Colo do Útero/virologia , Papillomaviridae , Infecções por Papillomavirus/epidemiologia , Adulto , Fatores Etários , Idoso , Costa Rica/epidemiologia , Estudos Transversais , Feminino , Humanos , Prevalência , Estudos Prospectivos
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