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Four single nucleotide polymorphism (SNP)-based human leukocyte antigen (HLA) imputation methods (e-HLA, HIBAG, HLA*IMP:02 and MAGPrediction) were trained using 1000 Genomes SNP and HLA genotypes and assessed for their ability to accurately impute molecular HLA-A, -B, -C and -DRB1 genotypes in the Human Genome Diversity Project cell panel. Imputation concordance was high (>89%) across all methods for both HLA-A and HLA-C, but HLA-B and HLA-DRB1 proved generally difficult to impute. Overall, <27.8% of subjects were correctly imputed for all HLA loci by any method. Concordance across all loci was not enhanced via the application of confidence thresholds; reliance on confidence scores across methods only led to noticeable improvement (+3.2%) for HLA-DRB1. As the HLA complex is highly relevant to the study of human health and disease, a standardized assessment of SNP-based HLA imputation methods is crucial for advancing genomic research. Considerable room remains for the improvement of HLA-B and especially HLA-DRB1 imputation methods, and no imputation method is as accurate as molecular genotyping. The application of large, ancestrally diverse HLA and SNP reference data sets and multiple imputation methods has the potential to make SNP-based HLA imputation methods a tractable option for determining HLA genotypes.
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Genoma Humano/genética , Antígenos HLA/genética , Haplótipos , Polimorfismo de Nucleotídeo Único/genética , Alelos , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Antígenos HLA/classificação , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Cadeias HLA-DRB1/genética , Humanos , População BrancaRESUMO
INTRODUCTION: This is about some results of a study called "Appraisal of the educational programmes and qualifications of health professions: a European Comparison" (in short: GesinE). It was carried out in the years 2009-2013, commissioned by the BMBF and supported by the BIBB. It is focussed on Germany, France, Great Britain, the Netherlands and Austria. The objectives have been (i) an inventory and comparative international synoptic presentation of education programmes of 16 health professions, (ii) a comparative international qualification analysis for the professions of radiographer, physiotherapist and nurse and (iii) the exposure of key aspects of the health-care and education systems in the compared countries. METHODS: This is a comparative multi-sectional study for which a mixed methods approach with qualitative and quantitative elements was used. RESULTS: According to the results of this study it is necessary that current qualification paths and competence profiles of the health professions are developed continuously in Germany. In this process the German education and the secondary education sector should not be underrated. At the same time the results suggest that there are advantages in some aspects in the academic education (which is the norm for most of the analysed professions in the surveyed countries) compared to the existing education programmes in the secondary sector. This in particular applies to the competence for finding and transferring scientific knowledge into practice and for implementing reflected processes for decision making. CONCLUSIONS: The results improve the basis of the current debate in Germany about the development and reorganisation of the profiles of health professions and their qualification in a European context.
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Competência Clínica/estatística & dados numéricos , Currículo/estatística & dados numéricos , Educação Médica/estatística & dados numéricos , Avaliação Educacional/estatística & dados numéricos , Definição da Elegibilidade/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Europa (Continente)RESUMO
Background External genital warts (EGWs, condylomata acuminata) are a common, highly contagious disease caused by human papillomavirus (HPV), predominantly HPV 6 and HPV 11. Green tea catechins have been identified for their immunostimulatory, antiproliferative and antitumour properties. Two phase III trials evaluated treatment of EGWs with ointment containing a mixture of green tea catechins (Polyphenon E), U.S. adopted name: sinecatechins). Objectives To obtain additional data on the efficacy and safety of Polyphenon E ointment in the treatment of EGWs from two randomized, double-blind, vehicle-controlled trials. Methods Men and women aged > or = 18 years (n = 1005), with two to 30 EGWs (12-600 mm(2) total area) applied vehicle (G(Veh); n = 207), Polyphenon E ointment 10% (G(10%); n = 401) or Polyphenon E ointment 15% (G(15%); n = 397) three times daily until complete clearance of all EGWs (baseline + new EGWs) or for a maximum of 16 weeks. Results A total of 1004 patients were evaluable for safety and 986 for efficacy; 838 completed treatment after 16 weeks. Complete clearance of all EGWs was obtained in 53.6% (G(10%)) and 54.9% (G(15%)) of patients with Polyphenon E vs. vehicle (35.4%) (P < 0.001). Statistically significant differences in clearance rates appeared after 6 weeks of active treatment. Odds ratios vs. G(Veh) for G(10%) [2.10; 95% confidence interval (CI) 1.49-2.98] and G(15%) (2.22; 95% CI 1.57-3.14) indicated about a twofold higher chance of complete clearance under active treatment. Time to complete clearance was shorter with active treatment (hazard ratios 1.57 and 1.87, respectively, for G(10%) and G(15%) vs. G(Veh) groups; P < 0.001). Recurrence rates during follow-up were low and similar across groups: 5.8%, 6.8% and 6.5% (G(Veh), G(10%) and G(15%) groups, respectively). Adverse events were evenly distributed across groups ( approximately 30% of patients). Severe local signs were more frequent but moderate in the active treatment groups (1.5%, 9.2% and 13.5% for G(Veh), G(10%) and G(15%) groups, respectively). Conclusions Polyphenon E ointment is effective and well tolerated in the treatment of EGWs.
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Antineoplásicos/uso terapêutico , Doenças do Ânus/tratamento farmacológico , Catequina/análogos & derivados , Doenças dos Genitais Femininos/tratamento farmacológico , Doenças dos Genitais Masculinos/tratamento farmacológico , Verrugas/tratamento farmacológico , Administração Tópica , Adulto , Antineoplásicos/efeitos adversos , Catequina/efeitos adversos , Catequina/uso terapêutico , Condiloma Acuminado/tratamento farmacológico , Método Duplo-Cego , Feminino , Humanos , Masculino , Preparações de Plantas/administração & dosagem , Preparações de Plantas/efeitos adversosAssuntos
Adjuvantes Imunológicos/uso terapêutico , Aminoquinolinas/uso terapêutico , Condiloma Acuminado/tratamento farmacológico , Indutores de Interferon/uso terapêutico , Feminino , Doenças dos Genitais Femininos/tratamento farmacológico , Humanos , Imiquimode , Masculino , Pomadas , Doenças do Pênis/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: To compare the efficacy and safety of valacyclovir hydrochloride and famciclovir for the treatment of herpes zoster. DESIGN: A double-blind, randomized, controlled, multicenter clinical trial in which patients received 7 days of treatment and were followed up for 24 weeks. SETTINGS: Patients reported directly to specialist centers or were referred from primary care centers. PATIENTS: There were 597 otherwise healthy immunocompetent outpatients, aged 50 years and older, who presented within 72 hours of onset of zoster rash. INTERVENTIONS: Treatment with valacyclovir hydrochloride (1 g 3 times daily) or famciclovir (500 mg 3 times daily) for 7 days. MAIN OUTCOME MEASURES: Resolution of zoster-associated pain and postherpetic neuralgia, rash healing, and treatment safety. RESULTS: Intent-to-treat analysis did not detect statistically significant differences for valacyclovir vs famciclovir on resolution of zoster-associated pain (hazard ratio, 1. 02; 95% confidence interval, 0.84-1.23; P =.84). Furthermore, no differences were evident between treatments on rash healing rates and on a range of analyses of postherpetic neuralgia. Safety profiles for valacyclovir and famciclovir were similar, with headache and nausea being the more common adverse events. CONCLUSIONS: Valacyclovir treatment is comparable to famciclovir treatment in speeding the resolution of zoster-associated pain and postherpetic neuralgia. Current wholesale prices indicate that valacyclovir is the more cost-effective treatment for herpes zoster ($83.90 vs $140.70 per course).
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2-Aminopurina/análogos & derivados , 2-Aminopurina/uso terapêutico , Aciclovir/análogos & derivados , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Herpes Zoster/tratamento farmacológico , Valina/análogos & derivados , Valina/uso terapêutico , 2-Aminopurina/economia , Aciclovir/economia , Idoso , Antivirais/economia , Análise Custo-Benefício , Método Duplo-Cego , Famciclovir , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/etiologia , Neuralgia/prevenção & controle , Dor/etiologia , Dor/prevenção & controle , Modelos de Riscos Proporcionais , Fatores de Tempo , Valaciclovir , Valina/economiaRESUMO
Although genital HPV types produce a broad spectrum of disease, the nongenital types are a bit more predictive. Particularly in the immunocompromised patient, it appears as though when they become symptomatic they cause warts. These warts can be a particular problem with immunocompromised patients where the malignant potential can also be expressed. Additional understanding of the relationship between the papilloma viruses and cutaneous oncology is very important. There needs to be an application of seroepidemiologic techniques to understand better the epidemiology and further research on more effective and less painful therapies.
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Papillomaviridae , Infecções por Papillomavirus , Infecções Tumorais por Vírus , Verrugas/virologia , Humanos , Hospedeiro Imunocomprometido , Verrugas/classificação , Verrugas/epidemiologia , Verrugas/terapiaRESUMO
In vaccine trials, diary questionnaires or vaccination report cards (VRCs) are used extensively to collect complaints reported by subjects or guardians following vaccination. These have not been evaluated for accuracy or standardized to facilitate tolerability comparisons among vaccines.Objectives -(1) Develop standardized, age-specific VRCs for collecting self-reported adverse events (AEs) in trials; (2) Evaluate whether complaints elicited by nurse examinations or telephone interviews were missed by VRCs.Methods -Vaccine-trial databases, focus groups, experts and experienced nurses were used to develop paediatric and adolescent/adult VRCs. VRCs were evaluated at four sites. The primary outcome was subjects with AEs missed on the VRC and reported in nurse examinations (for injection-site reactions) or telephone interviews (for systemic complaints).Results -Of 855 subjects, 96.5% completed VRCs. For systemic complaints, 1.5% (12/812) reported both no complaint on VRCs and at least one complaint in telephone interviews. For injection-site reactions, 5.1% (53/1030) of injection sites had both no reaction reported on VRCs and had reactions noted by nurse examination. No missed AEs were rated as severe.Conclusion -The data suggest VRCs provide a practical and reasonably complete method of eliciting complaints following vaccination. Copyright (c) 2000 John Wiley & Sons, Ltd.
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BACKGROUND: Basal cell carcinoma (BCC) responds to interferon therapy. Imiquimod is a cytokine and interferon inducer. OBJECTIVE: This randomized, double-blind pilot trial evaluated the safety and efficacy of imiquimod 5% cream versus vehicle in the treatment of BCC. METHODS: In this population of 35 patients with BCC, 24 received imiquimod 5% cream and 11 received vehicle cream in 1 of 5 dosing regimens for up to 16 weeks. Six weeks after treatment, an excisional biopsy of the target site was performed. RESULTS: BCC cleared (on the basis of histologic examination) in all 15 patients (100%) dosed twice daily, once daily, and 3 times weekly; in 3 of 5 (60%) patients dosed twice weekly; 2 of 4 (50%) dosed once weekly; and in 1 of 11 (9%) treated with vehicle. Adverse events were predominantly local reactions at the target tumor site, with the incidence and severity of local skin reactions declining in groups dosed less frequently. CONCLUSION: Imiquimod 5% cream shows clinical efficacy in the treatment of BCC.
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Aminoquinolinas/uso terapêutico , Carcinoma Basocelular/tratamento farmacológico , Indutores de Interferon/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Humanos , Imiquimode , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND AND OBJECTIVES: Education and counseling constitute a substantial portion of management of patients with genital herpes. Innovative methods for education about genital herpes are needed. GOAL: To test the ability of an interactive, computer-based program to educate patients about genital herpes. STUDY DESIGN: Persons seeking care at five urban offices were asked to participate. A knowledge test about genital herpes was administered before and after participation. Participants' satisfaction was assessed with a questionnaire. RESULTS: Four hundred thirty-five participants enrolled, and 428 completed the herpes knowledge test. Of six questions evaluated, a statistically significant increase in the proportion of correct answers was noted on five of six questions. Fifty-one percent of participants answered all the questions correctly after the program, compared with 39% before the program. Satisfaction with the program was very high. CONCLUSIONS: Innovative, computer-based programs can provide education and assist in the management of chronic sexually transmitted infections.
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Instrução por Computador , Herpes Genital , Educação de Pacientes como Assunto , Adolescente , Adulto , Idoso , Gerenciamento Clínico , Estudos de Avaliação como Assunto , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Herpes Genital/prevenção & controle , Herpes Genital/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Inquéritos e QuestionáriosRESUMO
Genital warts are manifestations of a common viral sexually transmitted disease (STD) that are often diagnosed and treated with a variety of clinical specialties. Unlike for other STDs, there is a general lack of a well-established treatment algorithm for the management of external genital warts. This, coupled with a wide variety of treatments and clinical settings, makes the development of a simple algorithm virtually impossible. In this review what is known and not known about current treatments and case management will be discussed.
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Condiloma Acuminado/tratamento farmacológico , Condiloma Acuminado/diagnóstico , HumanosRESUMO
A consensus process was undertaken to describe and evaluate current information and practice regarding the diagnosis, treatment, and evaluation of patients with external genital warts (EGWs) and their sex partners. This process developed a number of key statements that were based on strong evidence in the literature or reasonable suppositions and opinions of experts. Key statements included the following. In most cases, EGWs can be diagnosed clinically by visual inspection. No one treatment is ideal for all patients or all warts. Women with EGWs and female sex partners of men with EGWs are at increased risk for human papillomavirus-related cervical disease and, like all women, should be screened for cervical cancer. The diagnosis of EGWs in children requires a sexual abuse evaluation. Clinicians who treat EGWs have a responsibility to counsel patients and to provide information about the infectivity, diagnosis, treatment, and natural history of EGWs and general information about sexual health and other sexually transmitted diseases.
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American Medical Association , Condiloma Acuminado/diagnóstico , Condiloma Acuminado/terapia , Adolescente , Adulto , Canal Anal/patologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Lactente , Masculino , Programas de Rastreamento , Gravidez , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/diagnóstico , Estados Unidos , Neoplasias do Colo do Útero/diagnósticoRESUMO
Genital human papillomavirus infection is one of the most common sexually transmitted diseases. Imiquimod is a new agent, an immune-response modifier, that has been demonstrated to have potent in vivo antiviral and antitumor effects in animal models. The present prospective, multicenter, double-blind, randomized, vehicle-controlled trial evaluated the efficacy and safety of daily patient-applied imiquimod for up to 16 weeks for the treatment of external genital warts. Wart recurrence was investigated during a 12-week treatment-free follow-up period. In the intent-to-treat analysis, baseline warts cleared from 49 of 94 (52%) patients treated with 5% imiquimod cream, 13 of 90 (14%) patients treated with 1% imiquimod cream, and 3 of 95 (4%) vehicle-treated patients; the differences between the groups treated with vehicle and imiquimod were significant (P < 0.0001). For subjects who completed the follow-up period, recurrence rates after a complete response were 19% (9 of 48 patients) in the 5% imiquimod cream group, 17% (2 of 12) in the 1% imiquimod cream group, and 0% (0 of 3) in the vehicle-treated group. There were no systemic reactions, although local skin reactions (generally of mild or moderate severity) were common, particularly in the 5% imiquimod cream group. Local reactions caused two patients to discontinue treatment. The most frequently reported local skin reactions were erythema, excoriation or flaking, and erosion. Patient-applied 5% imiquimod cream is effective for the treatment of external genital warts and has a favorable safety profile.
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Aminoquinolinas/uso terapêutico , Condiloma Acuminado/tratamento farmacológico , Indutores de Interferon/uso terapêutico , Papillomaviridae , Administração Tópica , Adolescente , Adulto , Aminoquinolinas/administração & dosagem , Aminoquinolinas/efeitos adversos , Condiloma Acuminado/patologia , Método Duplo-Cego , Feminino , Humanos , Imiquimode , Indutores de Interferon/administração & dosagem , Indutores de Interferon/efeitos adversos , Masculino , RecidivaRESUMO
BACKGROUND: Genital warts are a common sexually transmitted disease caused by human papillomavirus. Imiquimod is a novel immune-response modifier capable of inducing a variety of cytokines, including interferon alfa, tumor necrosis factor-alpha, as well as interleukins 1, 6, and 8. In animal models imiquimod has demonstrated antiviral, antitumor, and adjuvant activity. In vitro, imiquimod has no antiviral or antitumor activity. OBJECTIVE: Our purpose was to determine the safety and efficacy of topical imiquimod for the treatment of external genital warts. METHODS: This prospective double-blind, placebo-controlled, parallel design clinical trial was performed in three outpatient centers, a public health clinic, a university-based clinic, and a private practice. One hundred eight patients with external genital warts (predominantly white men) were entered into the trial. Fifty-one patients were randomly selected to receive 5% imiquimod cream; 57 patients were randomly chosen to receive placebo cream. Study medication was applied three times weekly for up to 8 weeks. Patients whose warts cleared completely were observed for up to 10 weeks to determine recurrence rates. RESULTS: In the intent-to-treat analysis, the warts of 37% (19 of 51) of the imiquimod-treated patients and 0% (0 of 57) of the placebo group cleared completely (p < 0.001). In addition, many patients experienced a partial response. A reduction in baseline wart area of 80% or more was observed in 62% of imiquimod-treated patients (28 of 45) and 4% of the placebo group (2 of 50) (p < 0.001); a 50% reduction or more in wart area was noted in 76% of imiquimod-treated patients (34 of 45) and 8% of placebo recipients (4 of 50) (p < 0.001). Of imiquimod-treated patients whose warts cleared completely and who finished the 10-week follow-up period, 19% (3 of 16) experienced recurrences of warts. Imiquimod-treated patients experienced a significantly greater number of local inflammatory reactions than the placebo group. Symptoms and signs associated with the local inflammatory reactions included itching (54.2%), erythema (33.3%), burning (31.3%), irritation (16.7%), tenderness (12.5%), ulceration (10.4%), erosion (10.4%), and pain (8.3%). There were no differences in systemic reactions or laboratory abnormalities between treatment groups. CONCLUSION: Topical 5% imiquimod cream appears to have a significant therapeutic effect in the treatment of external genital warts.
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Adjuvantes Imunológicos/uso terapêutico , Aminoquinolinas/uso terapêutico , Condiloma Acuminado/terapia , Indutores de Interferon/uso terapêutico , Adjuvantes Imunológicos/efeitos adversos , Administração Tópica , Adulto , Aminoquinolinas/efeitos adversos , Condiloma Acuminado/patologia , Método Duplo-Cego , Feminino , Humanos , Imiquimode , Indutores de Interferon/efeitos adversos , Masculino , Pomadas , Estudos ProspectivosRESUMO
Objective: Education of patients with genital herpes about their disease is time consuming. To evaluate the effectiveness of an educational computer program, we developed a multimedia interactive presentation to teach patients about genital herpes. Such programs can supplement clinician visits for patients with genital herpes, or those at risk for HSV acquisition.Methods: Patients seeking care for genital herpes, or those at risk for HSV acquisition, were asked to participate in the program during routine clinic visits at 5 physician's offices nationwide. A self-administered 7 item herpes knowledge questionnaire was given before and after participation. An additional questionnaire evaluating the satisfaction with the program was also self-administered at completion.Results: 428 patients were enrolled and completed the pre- and post-knowledge questionnaire and 332 patients completed the satisfaction survey. On the pre-test, 20.1% of patients answered all questions correctly, 65.4% answered correctly 4 to 6 questions, and 14.5% 3 or less. On the post-test, 32.9% of patients answered all questions correctly, 61.5% answered correctly 4 to 6 questions, and 5.6% 3 or less (P <.001 for pre- and post-test comparison). A positive change in knowledge between pre- and post-test was seen on 6 of 7 items (P <.001 for all 6). The overall satisfaction with the program was high: the mean rating was 6.2 on a scale 1 (poor) to 7 (excellent).Conclusion: Computer-based education programs about genital herpes may provide a useful adjunct to teaching in physician offices and result in knowledge gain about the disease, at least short-term. Such programs may assist in management of chronic sexually transmitted infections.
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Human papillomaviruses (HPVs) are associated with a spectrum of different diseases in humans, including common warts and genital warts. Of more serious concern is the connection between certain HPV types and some malignancies, particularly cervical and anal cancer. DNA from HPV-16 and HPV-18, two types frequently found in cervical cancer tissue, can immortalize cells in laboratory cultures, unlike DNA from HPV types associated with benign genital lesions. Although it is unclear how high-risk HPV types cause cancer, studies indicate that malignant transformation involves the viral E6 and E7 gene products, which may exert their effect by interfering with the cellular proteins that regulate cell growth. The vast majority of those infected do not develop malignancies, indicating that HPV infection alone is not enough to cause cancer. Cofactors such as cigarette smoking, may be required before neoplasia can occur. The potential seriousness of HPV infections is suggested by the observations that the number of genital HPV infections diagnosed is increasing and that cervical cancer is the second leading cause of cancer deaths in women throughout the world.
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Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Infecções Tumorais por Vírus/virologia , Neoplasias do Ânus/virologia , Transformação Celular Neoplásica , DNA Viral/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Doenças dos Genitais Femininos/virologia , Doenças dos Genitais Masculinos/virologia , Humanos , Masculino , Infecções por Papillomavirus/complicações , Infecções Tumorais por Vírus/complicaçõesRESUMO
Although many treatments are available for genital warts caused by human papillomavirus (HPV), none are uniformly successful in the treatment of this disease. Most current treatment options work by destroying affected tissue, either by a cytotoxic or a physically ablative mode of action. Interferons have antiviral, antiproliferative, and immunomodulatory activities, but these have not translated into a high level of cure rates against warts. With all current treatments, recurrent warts are common. Therapies currently being investigated include a 5-fluorouracil/epinephrine collagen gel that achieves high concentrations of 5-fluorouracil at the site of injection. Other new treatment modalities focus on activating the host's immune system or improving the delivery of therapeutic compounds to the affected site. Imiquimod, a novel immune-response modifier, induces interferon and a number of other endogenous cytokines. A cream formulation containing 5% imiquimod resulted in good total clearance rates and generally tolerable side effects in controlled clinical trials of patients with external genital warts. Perhaps the most effective means for managing HPV disease would be a vaccine that prevents the occurrence of genital warts. Although it is unlikely that such a vaccine will be introduced in the near future, preliminary studies indicate that it may be possible to develop suitable prophylactic and therapeutic vaccines.
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Condiloma Acuminado/terapia , Papillomaviridae , Infecções por Papillomavirus/terapia , Infecções Tumorais por Vírus/terapia , Adjuvantes Imunológicos/uso terapêutico , Aminoquinolinas/uso terapêutico , Antimetabólitos/uso terapêutico , Antivirais/uso terapêutico , Condiloma Acuminado/tratamento farmacológico , Condiloma Acuminado/cirurgia , Condiloma Acuminado/virologia , Crioterapia , Quimioterapia Combinada , Eletrocirurgia , Fluoruracila/uso terapêutico , Humanos , Imiquimode , Injeções Intralesionais , Interferons/uso terapêutico , Ceratolíticos/uso terapêutico , Terapia a Laser , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/cirurgia , Infecções por Papillomavirus/virologia , Podofilina/uso terapêutico , Podofilotoxina/uso terapêutico , Infecções Tumorais por Vírus/tratamento farmacológico , Infecções Tumorais por Vírus/cirurgia , Infecções Tumorais por Vírus/virologiaRESUMO
BACKGROUND: Valaciclovir, the 1-valyl ester of acyclovir, has provided a peroral acyclovir bioavailability 3 to 5 times that of acyclovir itself and is rapidly and completely converted to acyclovir by the liver. Accordingly, valaciclovir has the same antiviral activity as acyclovir, but the potential for enhanced clinical activity and/or less frequent administration because of its superior pharmacokinetics. METHODS: We conducted a double-blind, placebocontrolled, patient-initiated clinical trial of peroral valaciclovir, 500 or 1000 mg, or matching placebo tablets twice daily for 5 days for the acute treatment of 1 episode of recurrent herpes genitalis among 987 otherwise healthy volunteers. RESULTS: Both doses of valaciclovir were equally effective. Patients receiving the lower dose of valaciclovir experienced a median episode length of 4.0 days compared with 5.9 days for those receiving placebo treatment (hazard ratio, 1.9; 95% confidence interval [Cl], 1.6-2.3). Valaciclovir therapy increased the proportion of patients in whom the development of vesicular and ulcerative lesions was prevented in comparison with placebo treatment: 31% vs 21% (relative risk, 1.5; 95% CI, 1.1-1.9). Valaciclovir therapy accelerated the resolution of pain (hazard ratio, 1.8; 95% CI, 1.5-2.1) and the time to cessation of viral shedding (hazard ratio, 2.9; 95% CI, 2.1-3.9). Adverse reactions among the valaciclovir groups were comparable with those of the placebo group. CONCLUSIONS: Valaciclovir therapy provided a clinically significant benefit to patients that included shortening of the duration of lesions, the duration of pain or discomfort, and the duration of virus shedding. In addition, this study, to our knowledge, provides the first convincing demonstration that antiviral therapy can prevent lesion development. These results should prompt a reconsideration of the role that episodic treatment plays in the management of recurrent herpes genitalis.