Cerebrospinal fluid challenges for the diagnosis of herpes simplex infection in the central nervous system / Desafios do exame do líquido cefalorraquidiano para o diagnóstico de infecção por herpes simplex no sistema nervoso central

Abstract Herpes simplex virus (HSV) is a cause of a severe disease of the central nervous system (CNS) in humans. The demonstration of specific antibodies in the cerebrospinal fluid (CSF) may contribute to the retrospective neurological diagnosis. However, the commercial immunological tests for HSV infection are for use in serum samples. Objective: The aim of the present study was to adapt a commercial kit anti-HSV IgG used for serum samples to be performed with a CSF sample. Methods: Forty CSF specimens from 38 patients with suspected CNS HSV infection were serially diluted for detecting anti-HSV IgG by enzyme immunoassay (EIA). The same samples were also analyzed with the polymerase chain reaction (PCR). Results: The sensitivity of EIA test for HSV was 5% (dilution 1:40) and 65% (dilution 1:2) in CSF, and HSV DNA PCR was 15%. The combined analysis of EIA (dilution 1:2) and PCR increased the sensitivity up to 72.5%. The inflammatory CSF was associated with positive HSV PCR. Conclusions: We demonstrated the importance to adapt serological anti-HSV IgG EIA test for CSF assays to increase the accuracy of the analysis, considering the low concentration of specific antibodies in CSF.

Resumo O vírus herpes simples (HSV) é um dos agentes causadores de uma doença grave no sistema nervoso central (SNC) em humanos. A detecção de anticorpos específicos no líquido cefalorraquidiano (LCR) pode contribuir para o diagnóstico neurológico retrospectivo. Entretanto, os testes imunológicos comerciais são para uso em amostras de soro. Objetivo: Adaptar um kit comercial sorológico anti-HSV IgG para ser utilizado no de LCR. Metodos: Quarenta amostras de LCR de 38 pacientes com suspeita de infecção por HSV no SNC foram diluídas pesquisa de anticorpos anti-HSV IgG pelo método imunoenzimático (EIA). Além disso, as mesmas amostras também foram analisadas por reação em cadeia da polimerase (PCR). Resultados: A sensibilidade do teste EIA para o HSV consistiu em 5% (diluição 1:40) e 65% (diluição 1:2) no LCR, e o PCR do DNA do HSV, 15%. A análise combinada de EIA (diluição 1:2) e PCR aumentou a sensibilidade para 72,5%. Houve associação entre presença do LCR inflamatório e PCR positiva para HSV. Conclusões: Demonstramos a importância na adaptação previa do teste sorológico anti-HSV IgG EIA para ensaios do no LCR, a fim de aumentar a acuracia da análise, considerando a baixa concentração de anticorpos específicos no LCR.

Usefulness of aqueous and vitreous humor analysis in infectious uveitis

OBJECTIVE: To evaluate the role of intraocular fluid analysis as a diagnostic aid for uveitis. METHODS: Twenty-eight samples (27 patients including 3 HIV-infected patients) with active (n=24) or non-active (n=4) uveitis were submitted to aqueous (AH; n=12) or vitreous humor (VH) analysis (n=16). All samples were analyzed by quantitative PCR for herpes simplex virus (HSV), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV) and Toxoplasma gondii. RESULTS: The positivity of the PCR in AH was 41.7% (5/12), with 50% (2/4) in immunocompetent and 67% (2/3) in HIV+ patients. The positivity of the PCR in VH was 31.2% (5/16), with 13% (1/8) in immunocompetent and 50% (4/8) in immunosuppressed HIV negative patients. The analysis was a determinant in the diagnostic definition in 58% of HA and 50% of VH. CONCLUSION: Even in posterior uveitis, initial AH analysis may be helpful. A careful formulation of possible clinical diagnosis seems to increase the chance of intraocular sample analysis being meaningful.

Minimum detection limit of an in-house nested-PCR assay for herpes simplex virus and varicella zoster virus

Introduction Herpes simplex virus (HSV) and varicella zoster virus (VZV) are responsible for a variety of human diseases, including central nervous system diseases. The use of polymerase chain reaction (PCR) techniques on cerebrospinal fluid samples has allowed the detection of viral DNA with high sensitivity and specificity. Methods Serial dilutions of quantified commercial controls of each virus were subjected to an in-house nested-PCR technique. Results The minimum detection limits for HSV and VZV were 5 and 10 copies/µL, respectively. Conclusions The detection limit of nested-PCR for HSV and VZV in this study was similar to the limits found in previous studies. .

Herpes Simplex Virus Duodenitis Accompanying Crohn's Disease / 대한소화기학회지

Herpes simplex virus (HSV) is a recognized cause of gastrointestinal infection in immunodeficient patients. Although a few cases of HSV gastritis and colitis in immunocompromised patients have been reported, there are no reports of HSV duodenitis in patients with Crohn's disease (CD). A 74-year-old female was admitted with general weakness and refractory epigastric pain. She had been diagnosed with CD three years ago. Esophagogastroduodenoscopy (EGD) revealed diffuse edematous and whitish mucosa with multiple erosions in the duodenum. Considering the possibility of viral co-infection, cytomegalovirus (CMV) immunohistochemical staining, PCR, and cultures of duodenal biopsies were performed, all of which were negative with the exception of the isolation of HSV in culture. After administration of intravenous acyclovir for 1 week, follow-up EGD showed almost complete resolution of the lesions and the patient's symptoms improved. In CD patients with refractory gastrointestinal symptoms, HSV, as well as CMV, should be considered as a possible cause of infection, so that the diagnosis of viral infection is not delayed and the appropriate antiviral treatment can be initiated.

Diagnosis and quantitative detection of HSV DNA in samples from patients with suspected herpes simplex encephalitis

Diagnosis of herpes simplex encephalitis (HSE) is based on the detection of herpes simplex virus (HSV) DNA in patients' CSF samples. HSV DNA quantitation has the potential for estimating the effects of antiviral therapy. The aim of this study was to diagnose HSV DNA in HSE suspected patients and the quantitative analysis of its genome using real-time PCR to assess the value of the viral load in the course of antiviral treatment. The CSF samples were collected from 236 consecutive HSE suspected patients from November 2004 to May 2008. Upon DNA extraction, the samples were analyzed by Real-Time PCR assay. A set of primers amplified a common sequence of HSV glycoprotein B gene. The copy numbers of unknown samples were expressed via a standard curve drawn with a known amount of amplified cloned plasmid. Of the 236 samples, 137 (58 percent) came from males and 99 (42 percent) from females. The HSV genome was detected in 22 (9.3 percent) patients by PCR, 13 males/ 9 females. Serial CSF samples were available from 10 of the 22 patients. The range of the HSV DNA copy numbers in the clinical samples ranged from 2.5 × 10² to 1.7 × 10(6) copies/mL of CSF. Quantitative PCR results can be helpful in evaluating the efficacy of antiviral therapy in the above-mentioned patients. There is an association between the initial viral load and the duration of treatment course.

Enterovirus and herpesviridae family as etiologic agents of lymphomonocytary meningitis, Southern Brazil / Enterovirus e família herpesviridae como agentes etiológicos de meningites linfomonocitárias, no sul do Brasil

Viral meningitis is a common infectious disease of the central nervous system (CNS) that occurs worldwide. The aim of this study was to identify the etiologic agent of lymphomonocytary meningitis in Curitiba, PR, Brazil. During the period of July 2005 to December 2006, 460 cerebrospinal fluid (CSF) samples with lymphomonocytary meningitis were analyzed by PCR methodologies. Fifty nine (12.8 percent) samples were positive. Enteroviruses was present in 49 (83 percent) samples and herpes virus family in 10 (17 percent), of these 6 (10 percent) herpes simplex virus, 1 (2 percent) Epstein Barr virus, 2 (3 percent) human herpes virus type 6 and 1 (2 percent) mixed infection of enterovirus and Epstein Barr virus. As conclusion enterovirus was the most frequent virus, with circulation during summer and was observed with higher frequency between 4 to 17 years of age. PCR methodology is an important method for rapid detection of RNA enterovirus and DNA herpesvirus in CSF.

A meningite viral é uma síndrome infecciosa comum do sistema nervoso central (SNC), que ocorre no mundo inteiro. O objetivo deste estudo foi identificar o agente etiológico de meningite linfomonocitária em Curitiba, PR, Brasil. Durante o período de julho de 2005 a dezembro de 2006, 460 amostras com meningite linfomonocitária foram analisadas por metodologias de PCR. Cinquenta e nove (12,8 por cento) amostras foram positivas. Enterovirus estava presente em 49 (83 por cento) amostras e herpes vírus em 10 (17 por cento), destas 6 (10 por cento) HSV, 1 (2 por cento) EBV, 2 (3 por cento) HHV- 6 e 1 (2 por cento) infecção mista de enterovírus e EBV. Conclui-se que o enterovirus foi o vírus mais frequente, com a circulação durante o verão. Houve maior número de amostras positivas entre 4 a 17 anos. A metodologia de PCR é um importante método para a detecção rápida de RNA de enterovirus e DNA do herpesvirus no LCR.

Enhanced anti-tumor effect of a gene gun-delivered DNA vaccine encoding the human papillomavirus type 16 oncoproteins genetically fused to the herpes simplex virus glycoprotein D

Anti-cancer DNA vaccines have attracted growing interest as a simple and non-invasive method for both the treatment and prevention of tumors induced by human papillomaviruses. Nonetheless, the low immunogenicity of parenterally administered vaccines, particularly regarding the activation of cytotoxic CD8+ T cell responses, suggests that further improvements in both vaccine composition and administration routes are still required. In the present study, we report the immune responses and anti-tumor effects of a DNA vaccine (pgD-E7E6E5) expressing three proteins (E7, E6, and E5) of the human papillomavirus type 16 genetically fused to the glycoprotein D of the human herpes simplex virus type 1, which was administered to mice by the intradermal (id) route using a gene gun. A single id dose of pgD-E7E6E5 (2 µg/dose) induced a strong activation of E7-specific interferon-γ (INF-γ)-producing CD8+ T cells and full prophylactic anti-tumor effects in the vaccinated mice. Three vaccine doses inhibited tumor growth in 70 percent of the mice with established tumors. In addition, a single vaccine dose consisting of the co-administration of pgD-E7E6E5 and the vector encoding interleukin-12 or granulocyte-macrophage colony-stimulating factor further enhanced the therapeutic anti-tumor effects and conferred protection to 60 and 50 percent of the vaccinated mice, respectively. In conclusion, id administration of pgD-E7E6E5 significantly enhanced the immunogenicity and anti-tumor effects of the DNA vaccine, representing a promising administration route for future clinical trials.

Diagnóstico microbiológico de infecciones de transmisión Sexual: Parte II. ITS virales / Microbiologic diagnosis of sexually transmitted diseases: Part II. STD of viral origin

Sexually transmitted diseases are highly prevalent and a public health concern worldwide. Herpes simplex virus (HSV) and human papilloma virus (HPV) are described. The development of rapid, sensible and specific diagnostic assays has been difficult because of their pathogenic features. In the last years, molecular biology based techniques allowed a better and wider range of diagnosis, as in the HPV-cancer association. In this article, standardized diagnostic methodologies for HSV and HPV are reviewed.

Las Infecciones virales de transmisión sexual son altamente prevalentes y constituyen un problema de salud pública en el mundo. Entre los agentes que se contagian por esta vía, se describe acerca de virus herpes simplex (HSV) y virus papiloma humano (HPV). Las características patogénicas de estas infecciones han dificultado la implementación de técnicas diagnósticas rápidas, sensibles y específicas para el diagnóstico clínico habitual. En los últimos años las metodologías diagnósticas sustentadas en la biología molecular han permitido mej orar y ampliar el rango de diagnóstico posible para estos agentes infecciosos y relacionarlos con otras patologías, como es el caso de HPV y cáncer. En el presente artículo se revisan metodologías diagnósticas implementadas para el diagnóstico microbiológico de HSV y de HPV.

Detecção do vírus herpes simples por reação em cadeia da polimerase em pacientes com ceratite herpética típica ou atípica / Molecular detection of herpes simplex virus by polymerase chain reaction in patients with typical and atypical herpetic keratitis

OBJETIVO: Avaliação dos pacientes com o quadro clínico de ceratite herpética (CH) típicas e atípicas, pela reação em cadeia da polimerase (PCR) correlacionando com o diagnóstico clínico. MÉTODOS: Foi realizada a PCR em 28 pacientes com ceratite herpética típica e atípica. RESULTADOS: A PCR foi positiva em 57,14 por cento (n=16) do total (n=28). Nos casos de CH típica a positividade foi de 60,00 por cento (n=12) em 20 casos. Para CH epitelial a positividade foi de 69,23 por cento (n=9), sendo 77,78 por cento (n=7) apenas para as lesões epiteliais dendríticas. Os casos de CH atípica apresentaram positividade de 50 por cento (n=4) em oito casos. CONCLUSÃO: Quadro clínico típico de CH teve boa correlação com o resultado positivo observado na PCR. Entretanto, metade dos pacientes com o quadro de CH atípica apresentou PCR positivo, portanto, o exame do PCR é teste importante para o auxílio e diagnóstico da CH. No caso de CH estromal, foi demonstrado que a técnica da PCR conseguiu identificar o vírus HSV.

PURPOSE: To evaluate patients with clinically typical and atypical herpetic keratitis (HK) by means of polymerase chain reaction (PCR) as compared with the clinical diagnosis. METHODS: PCR in 28 patients with clinical symptoms of typical and atypical HK was performed. RESULTS: PCR was positive in 57.14 percent (n=16) of the total cases (n=28). The test was positive in 60.0 percent (n=12) of the 20 typical HK cases. For epithelial HK, the test was positive in 69.23 percent (n=9), and 77.78 percent (n=7) only for dendritic injuries. Atypical HK presented a positive test in 50 percent (n=4) of eight cases. CONCLUSION: Clinical typical picture of HK had a good correlation with the positive result of PCR, mainly for epithelial injury of the dendritic type. However, 50 percent of the patients with atypical HK presented positive PCR. This result showed that PCR test can provide an effective HK diagnosis. In the stromal case of HK, PCR was a useful technique to identify HSV virus.

Relative efficiency of polymerase chain reaction and enzyme-linked immunosorbant assay in determination of viral etiology in congenital cataract in infants.

BACKGROUND: Perinatal viral infections of fetus are among the leading causes of congenital cataract and identifying the viral etiology is important. OBJECTIVES: To detect the presence of Rubella virus (RV), herpes simplex virus (HSV) and cytomegalovirus (CMV) in lens aspirate specimens obtained from patients with congenital cataract and relate the results with serology. SETTING AND DESIGN: Prospective study carried out in tertiary care hospital. MATERIALS AND METHODS: Fifty lens aspirates from 50 infants with congenital cataract were subjected to HSV, RV isolation and polymerase chain reaction (PCR) for detection of HSV and CMV. Reverse transcription polymerase chain reaction (RT-PCR) was applied for RV detection. Peripheral blood specimens were screened for anti-HSV, RV and CMV antibodies by enzyme-linked immunosorbant assay (ELISA). RESULTS: Rubella virus was detected in nine (18%) lens aspirates, by nRT-PCR which includes six positive by culture. HSV-2 DNA was detected in nine other lens aspirates, while CMV was not detected by PCR. Serological results did not correlate with the presence of viruses in the lens aspirates. This is the first report of detection of HSV-2 DNA in cases of congenital cataract. CONCLUSIONS: Cytomegalovirus may not be playing a significant role in causation of congenital cataract. The role of serology in identifying causative viral infection for congenital cataract needs to be re-evaluated.

Imaging of Viral Thymidine Kinase Gene Expression by Replicating Oncolytic Adenovirus and Prediction of Therapeutic Efficacy

PURPOSE: We have used a genetically attenuated adenoviral vector which expresses HSVtk to assess the possible additive role of suicidal gene therapy for enhanced oncolytic effect of the virus. Expression of TK was measured using a radiotracer-based molecular counting and imaging system. MATERIALS AND METHODS: Replication-competent recombinant adenoviral vector (Ad-deltaE1B19/55) was used in this study, whereas replication-incompetent adenovirus (Ad-deltaE1A) was generated as a control. Both Ad-deltaE1B19/55-TK and Ad-deltaE1A-TK comprise the HSVtk gene inserted into the E3 region of the viruses. YCC-2 cells were infected with the viruses and incubated with 2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl-5-iodouracil (I-131 FIAU) to measure amount of radioactivity. The cytotoxicity of the viruses was determined, and gamma ray imaging of HSVtk gene was performed. MTT assay was also performed after GCV treatment. RESULTS: On gamma counter-analyses, counts/minute (cpm)/microgram of protein showed MOIs dependency with deltaE1B19/55-TK infection. On MTT assay, Ad-deltaE1B19/55-TK led to more efficient cell killing than Ad-deltaE1A-TK. On plate imaging by gamma camera, both Ad-deltaE1B19/55-TK and Ad-deltaE1A-TK infected cells showed increased I-131 FIAU uptake in a MOI dependent pattern, and with GCV treatment, cell viability of deltaE1B19/55-TK infection was remarkably reduced compared to that of Ad-deltaE1A-TK infection. CONCLUSION: Replicating Ad-deltaE1B19/55-TK showed more efficient TK expression even in the presence of higher-cancer cell killing effects compared to non-replicating Ad-deltaE1A-TK. Therefore, GCV treatment still possessed an additive role to oncolytic effect of Ad-deltaE1B19/55-TK. The expression of TK by oncolytic viruses could rapidly be screened using a radiotracer-based counting and imaging technique.

Estudio clínico y virológico en un grupo de niños chilenos con herpes ocular: análisis genómico de las cepas / Clinical-virological study in chilean children with ocular herpes: genomic analysis of strains

Objetivo: Caracterizar el diagnóstico de infección ocular por virus herpes simples (HSV) en un grupo de niños chilenos, mediante el estudio clínico y de laboratorio virológico. Métodos: La población estudiada comprendió niños menores de 15 años, con diagnóstico clínico de herpes ocular, que fueron atendidos por los autores y un grupo de oftalmólogos entrenados especialmente para el estudio. Junto con detallar el tipo de infección herpética, a todos los pacientes se les tomaron muestra para estudio virológico que incluyó estudio de cultivos celulares y posteriormente técnica de reacción en cadena de polimerasa (PCR), con el fin de tipificar las cepas y características genómicas del virus infectante. Resultados: El estudio enroló 18 niños, cuyas edades fluctuaron entre los 40 días y 13 años, con una media de 6 años. De las formas clínicas observadas, la más frecuentes fueron la blefaritis y la queratitis dendrítica constituyendo en 27 y 22 por ciento de los casos, respectivamente. El diagnóstico de HSV fue confirmado en 15 de 18 pacientes, constituyendo un 83 por ciento de positividad. 14 de 15 casos correspondieron a HSV tipo 1, y en un niño se diagnóstico infección por HSV tipo 2. Los antecedentes clínicos de este caso confirmaron que se trataba de una infección perinatal, lo que permitió instaurar el tratamiento en forma oportuna. El estudio permitió identificar un caso de excreción ocular viral asintomática, lo que sumando a un cuadro de recurrencias múltiples obligó a indicar terapia profiláctica permanente con aciclovir. Conclusiones: La blefaritis y queratitis herpética constituyeron en conjunto el 70 por ciento de los casos. El rendimiento celular y PCR fue elevado en los casos con alto índice de replicación viral, como la queratitis y blefaritis. En los casos con menor replicación, como queratitis estromal o conjuntivitis, el estudio PCR demostró una mayor sensibilidad que el estudio en cultivo celular. La presencia de un caso de infección perinatal por HSV-2 pudiera ser indicativo de un aumento en la frecuencia de esta forma de presentación.

Use of uniplex polymerase chain reaction & evaluation of multiplex PCR in the rapid diagnosis of viral retinitis.

BACKGROUND & OBJECTIVES: Polymerase chain reaction (PCR) has been known to be a rapid and accurate diagnostic test for causative viruses of viral retinitis, but cost is the limiting factor. In the present study an attempt was made to standardize a multiplex PCR (mPCR) on intraocular specimens from patients with viral retinitis for the detection of one or more viruses [herpes simplex virus (HSV), varicella zoster virus (VZV) or cytomegalovirus (CMV)] in order to reduce the period of time required for uniplex polymerase chain reaction (uPCR). METHODS: Using the uniplex PCR (uPCR) primers, a nested mPCR was developed and standardized for the simultaneous detection of HSV, VZV and CMV. mPCR and uPCRs were applied on 9 stored specimens and 38 prospective specimens obtained from patients with viral retinitis. RESULTS: The specificity and sensitivity of the mPCR were concordant with that of uPCRs. Clinical specificity and sensitivity of mPCR was further confirmed by the detection of the same herpes viral DNA on the 9 stored specimens. Of the 38 specimens collected prospectively, mPCR detected HSV in 3 (7.9%), VZV in 9 (23.7%), CMV in 5 (13.2%) and both VZV and CMV in 2 (5.3%). Co-infections of two viruses were found in 7 (14.89%) of the 47 specimens. INTERPRETATION & CONCLUSION: mPCR is a rapid, specific and sensitive diagnostic tool in viral retinitis. Compared to uPCR, mPCR is less time-consuming and cost effective.

Prevalence of Chlamydia trachomatis & herpes simplex virus in males with urethritis & females with cervicitis attending STD clinic.

BACKGROUND & OBJECTIVES: Cervicitis and urethritis due to Chlamydia trachomatis are common sexually transmitted diseases. However, there is a paucity of information on urethritis and mucopurulent cervicitis due to herpes simplex virus (HSV) from India. We used polymerase chain reaction (PCR) to find out the prevalence of C. trachomatis and HSV associated urethritis in males and mucopurulent cervicitis in females attending a sexually transmitted diseases (STD) clinic. METHODS: Twenty five endocervical swabs from 25 women with mucopurulent cervicitis and 75 urethral swabs from 72 males with urethritis were processed for the detection of C. trachomatis and HSV by antigen detection by fluorescent antibody test (FAT), culture and PCR. RESULTS: Among the 25 women, one (4.0%) was positive for C. trachomatis and 3 (12.0%) were positive for HSV by PCR. FAT and culture were negative. Nine (12.0%) of the 75 urethral swabs were positive for C. trachomatis and 5 (6.6%) were positive for HSV by PCR. Among the 9 positive by PCR for C. trachomatis, 3 (4.0%) were positive by FAT. Cultures for both organisms were negative. INTERPRETATION & CONCLUSION: Endocervicitis and male urethritis due to C. trachomatis and HSV are not uncommon among high-risk individuals. The diagnosis could be established mainly by PCR.

Nuevos métodos diagnósticos para virus herpes simplex (HSV): importancia de la serología / New diagnostic methods for herpes simplex virus (HSV): the importance of serology

En los últimos años el gran avance de la biología molecular aplicada al diagnóstico de agentes infecciosos ha dado como resultado nuevas metodologías, más sensibles, específicas y rápidas, al alcance del médico clínico. Para el diagnóstico de los virus herpes simplex (HSV), los métodos de detección genómica y las nuevas técnicas específicas de serología han cubierto nuevas posibilidades de confirmación etiológica frente a la sospecha clínica, todo lo cual resulta finalmente en un mejor manejo terapéutico y epidemiológico.

In recent years, the great advances in the field of molecular biology, applied to diagnosis of infectious agents have resulted in new, more sensible, specific and faster methods that are more accessible to the physician. In the case of herpes simplex virus (HSV), genomic methods and specific serology have opened new possibilities for etiologic confirmation, resulting in better therapeutic and epidemiological management.

Estudio clínico virológico en un grupo de niños chilenos con herpes ocular: análisis genómico de las cepas / Clinic-virological study in chilean children with ocular herpes: genomic analysis of strains

Se estudiaron todos los niños menores de 15 años, con diagnóstico clínico de herpes ocular, efectuado por oftalmólogos de servicios oftalmológicos de la Facultad de Medicina de la Universidad de Chile y de un centro oftalmológico privado, desde abril de 1995 a abril de 1996, en Santiago de Chile. Se consignó información clínico epidemiológica, examen clínico y se obtuvieron mediante torulado muestras de conjuntiva y/o córnea del ojo afectado, conjuntiva del ojo sano y mucosa oral, utilizando una técnica estándar. Se efectuó aislamiento viral en células VERO (ATCCL81). En caso de detectarse efecto citopático, el aislado viral se propagó y almacenó para su estudio. Se efectuó identificación y tipificación viral con anticuerpos tipo específicos marcados con fluoresceína (DAKO). Se efectuó amplificación génica y análisis con enzimas de restricción. Resultados: se determinó que 14/15 aislados correspondían a herpes simplex tipo I (HSV-I) y uno a HSV-2, el cual muy probablemente correspondió a una infección perinatal por este virus. Las cepas de HSV-I presentaron patrones genómicos distintos entre sí y con la cepa de referencia norteamericana HSV-IF. La forma de presentación más frecuente fue de blefaritis herpética, seguida por la dendrita corneal, tanto en el primer espisodio clínico como en las recurrencias y en estas últimas, tiende a presentarse la misma forma clínica. La tasa de recurrencia es mayor que en la población adulta. La infección fue unilateral con la excepción de un caso con distintas formas de presentación en cada ojo y aislamiento simultáneo bilateral. En dos casos fue posible detectar excreción oral del virus subclínica

Identidad genómica entre virus herpes simplex aislados de lesiones glúteas y genitales / Genomic identity among herpes simplex virus isolated from buttock and genital injuries

El herpes glúteo es originado por el HSV-2 en más del 70 por ciento de los casos y un 58 por ciento de los pacientes refiere antecedentes de herpes genital. Con el fin de investigar la existencia de identidad genómica entre los HSV aislados de lesiones glúteas y genitales, se estudiaron 21 HSV: 9 obtenidos de lesiones glúteas; 8 de lesiones genitales y 4 de secreción vaginal. Estos aislados provenían de 5 pacientes portadores de herpes glúteo y genital. El estudio se realizó mediante aislamiento viral, tipificación con anticuerpos monoclonales y análisis genómico con enzimas de restricción. Se demostró que, 18 aislados correspondían a HSV-2 y 3 a HSV-1. El estudio con enzimas de restricción corroboró los resultados obtenidos con anticuerpos monoclonales y permitió definir la existencia de 4 tipos de patrón HSV-2 y dos de HSV-1. Se estableció la existencia de doble infección herpética en dos de las pacientes analizadas. Los pérfiles de los genomas virales obtenidos de aislados glúteos se correspondieron en forma idéntica con el de los aislados genitales y de secreción vaginal en cada una de las pacientes estudiadas. Los resultados anteriores nos permiten confirmar la hipótesis que lesiones herpéticas genitales y glúteas pueden ser originadas por la misma cepa viral y tener un origen de infección común

El impacto de la biología molecular en el estudio de las infecciones virales / The impact of molecular biology in the study of viral infections

El desarrollo de las técnicas de biología molecular ha sido trascendental para el avance de la Virología en la última década. En esta revisión se presentan algunos de los avances más importantes que ha generado el estudio de dos de los virus con mayor impacto en los últimos años y en donde la aplicación de esa metodología ha sido crucial. La primera parte corresponde al VIRUS HERPES SIMPLE (HSV) cuya complejidad genética es asombrosa ya que posee como material genético un DNA de doble cadena, con 152 kilopares de bases, que presenta aproximadamente 75 marcos de lectura (ORF), que pueden codificar por lo menos para unas 72 proteínas diferentes. Estos genes se expresan durante el ciclo viral a través de un proceso altamente regulado y coordinado, como se observa en las neuronas del sistema nervioso central, a diferencia de lo que ocurre durante la latencia en neuronas sensoriales, en donde estos genes están apagados. El otro virus analizado es el VIRUS DE LA INMUNODEFICIENCIA HUMANA (HIV), el cual es un ejemplo de la enorme cantidad de información que se ha generado en menos de una década de estudio y que ha conducido no sólo a la elaboración del mapa genético viral de los genes estructurales (gag, pol y env), sino que también se han identificado por lo menos otros siete genes adicionales, cuya función es la regulación o modulación de la expresión genética viral. En relación a la patogénesis del síndrome de inmunodeficiencia adqirida (SIDA), se sabe que éste se desarrolla varios años después de la infección viral inicial; sin embargo, la replicación viral ocurre como un proceso continuo, aún en ausencia de infección clínica, lo que sugiere que la infección por HIV se inicia como un proceso caracterizado por una replicación viral persistente y una progresiva disfunción inmunológica.

Herpes simplex virus genes controlling reactivation from latency in rabbit eye model.

Using the rabbit eye model of latency, herpes simplex virus type 1 strain McKrae invariably reactivated after epinephrine iontophoresis, whereas type 2(HSV-2) virus strain HG 52 failed to reactivate. Both strains established a latent infection with the same frequency. To identify the viral genes involved in this reactivation difference, intertypic recombinants were selected following cotransfection of intact McKrae DNA and Xba I or Hpa I cleaved HG52 DNA. Eleven separately obtained recombinants containing HG52 inserts between 0.35-0.56 and/or 0.82-1.0 map units (mu) were isolated but as four that were tested reactivated with the same frequency as the parental Mckrae virus, it was established that the genes encoded between these map coordinates do not determine the reactivation difference.