Incidence of enterovirus in patients with acute gastroenteritis.

Enteroviruses (EV) have been linked to lymphocytic meningitis and exanthems, but they may also be involved in acute gastroenteritis (AGE), a condition whose aetiological agent often remains unidentified. In this work 1214 samples from individuals with AGE were studied with the aim of establishing the incidence of EV. The samples were collected between September and December in three different years and subjected to real-time genomic amplification in order to determine the viral load (VL). Of the 1214 samples studied, infection by a single virus was found in 328 cases (27%) and coinfection in 69 (5.7%). While adenoviruses (AdV) were the most frequent (14.8% of total), EV were present in 126 (10.4%) of the individuals tested. Of the 126 EV-positive samples, this virus was found as a single infection and coinfection in 76 (6.3%) and 50 (4.1%) cases, respectively. VL for EV was 5.58±1.51 log copies/ml (range 3.73-9.69) in the former and 6.27±1.75 (range 3.73-10.5) (p=0.02) in the latter. EV were identified in 97 children under 5 (16.9%) and in 29 (4.5%) patients over 5. Patients less than 5 years showed a higher VL that those more than 5 years age [6.08±1.57 (range 3.82-9.69) vs. 5.07±1.53 (range 3.73-10.58); (p=0.002)]. There was a high incidence of EV in AGE patients, and they were more frequent in those under 5, where they were found to replicate more efficiently. These results therefore indicate that testing for EV should be included in the diagnosis of AGE.

Viral infections of the central nervous system in Spain: a prospective study.

The aim of the study was to determine the incidence of viruses causing aseptic meningitis, meningoencephalitis, and encephalitis in Spain. This was a prospective study, in collaboration with 17 Spanish hospitals, including 581 cases (CSF from all and sera from 280): meningitis (340), meningoencephalitis (91), encephalitis (76), febrile syndrome (7), other neurological disorders (32), and 35 cases without clinical information. CSF were assayed by PCR for enterovirus (EV), herpesvirus (herpes simplex [HSV], varicella-zoster [VZV], cytomegalovirus [CMV], Epstein-Barr [EBV], and human herpes virus-6 [HHV-6]), mumps (MV), Toscana virus (TOSV), adenovirus (HAdV), lymphocytic choriomeningitis virus (LCMV), West Nile virus (WNV), and rabies. Serology was undertaken when methodology was available. Amongst meningitis cases, 57.1% were characterized; EV was the most frequent (76.8%), followed by VZV (10.3%) and HSV (3.1%; HSV-1: 1.6%; HSV-2: 1.0%, HSV non-typed: 0.5%). Cases due to CMV, EBV, HHV-6, MV, TOSV, HAdV, and LCMV were also detected. For meningoencephalitis, 40.7% of cases were diagnosed, HSV-1 (43.2%) and VZV (27.0%) being the most frequent agents, while cases associated with HSV-2, EV, CMV, MV, and LCMV were also detected. For encephalitis, 27.6% of cases were caused by HSV-1 (71.4%), VZV (19.1%), or EV (9.5%). Other positive neurological syndromes included cerebellitis (EV and HAdV), seizures (HSV), demyelinating disease (HSV-1 and HHV-6), myelopathy (VZV), and polyradiculoneuritis (HSV). No rabies or WNV cases were identified. EVs are the most frequent cause of meningitis, as is HSV for meningoencephalitis and encephalitis. A significant number of cases (42.9% meningitis, 59.3% meningoencephalitis, 72.4% encephalitis) still have no etiological diagnosis.

Effect of killer immunoglobulin-like receptors in the response to combined treatment in patients with chronic hepatitis C virus infection.

Killer immunoglobulin-like receptors (KIRs) are related to the activation and inhibition of NK cells and may play an important role in the innate response against infection with viruses such as hepatitis C virus (HCV). We examined whether the different combinations of KIRs with their HLA class I ligands influenced the response to combined treatment (pegylated alpha interferon and ribavirin) of patients infected by HCV. A total of 186 consecutive patients diagnosed with chronic HCV infection were analyzed. Seventy-seven patients exhibited HCV RNA levels at 6 months posttreatment and were called nonresponders (NR), while 109 cleared viral RNA and were named sustained viral responders (SVR). Patients were typed for HLA-B, HLA-Cw, KIR genes, and HCV genotype. In our study, the frequency of the KIR2DL2 allele was significantly increased in NR (P < 0.001; odds ratio [OR] = 1.95), as was the frequency of the KIR2DL2/KIR2DL2 genotype (P < 0.005; OR = 2.52). In contrast, the frequencies of the KIR2DL3 genotype (P < 0.001) and KIR2DL3/KIR2DL3 genotype (P < 0.05; OR = 0.54) were significantly increased in the SVR. Different combinations of KIR2DL2 and KIR2DL3 alleles with their ligands were analyzed. The frequency of the KIR2DL2/KIR2DL2-HLA-C1C2 genotype was significantly increased in the NR (P < 0.01; OR = 3.15). Additionally, we found a higher frequency of the KIR2DL3/KIR2DL3-HLA-C1C1 genotype in the SVR group (P < 0.05; OR = 0.33). These results were not affected by the HCV genotype. In conclusion, patients who carried the KIR2DL2/KIR2DL2-HLA-C1C2 genotype were less prone to respond to treatment. However, the KIR2DL3/KIR2DL3-HLA-C1C1 genotype clearly correlated with a satisfactory response to treatment, defined by the clearance of HCV RNA.

Molecular identification of two genotypes of mumps virus causing two regional outbreaks in Asturias, Spain.

BACKGROUND: In spite of universal vaccination, several sporadic cases of mumps infection, which could produce outbreaks, are detected every year in different countries. OBJECTIVE: Mumps virus strains causing two regional outbreaks in Asturias (Spain) were phylogenetically characterized. STUDY DESIGN: Mumps virus strains, which were detected in samples from patients belonging to two regional outbreaks in Asturias, were characterized by sequencing of the SH gene and further alignment to homologous sequences of representative strains of the different mumps genotypes. RESULTS: Two different strains (Ast/SP02 and Ast/SP07) were isolated. Sequence analysis revealed that while Ast/SP02 belonged to genotype H, Ast/SP07 was phylogenetically close to UK02-19, a reference strain for a new genotype. Both strains belonged to different genotypes from those used in the vaccination (Jeryl-Lynn strain is genotype A). CONCLUSION: Mumps virus strains different from those used in vaccination program can cause mumps outbreaks even in vaccinated patients.

Cytomegalovirus replication and "herpesvirus burden" as risk factor of cardiovascular events in the first year after renal transplantation.

Cytomegalovirus (CMV) infection alone or in combination with other pathogens ("pathogen burden") has been postulated as a factor producing arteriosclerosis in some solid organ transplant recipients. The aim of this study was to assess whether the patients with CMV replication and/or "herpesvirus burden" experienced a greater incidence of cardiovascular events during the first year after kidney transplantation. One hundred twenty-one consecutive transplant recipients were prospectively studied for CMV replication using antigenemia and polymerase chain reaction (PCR) weekly during the 4 first months, and monthly thereafter for 1 year. Simultaneously, nested-PCR for human herpes virus (HHV)-6 and HHV-7 were performed to yield a herpesvirus burden (as determined by seropositivity), including CMV, herpes simplex virus (HSV), varicella-zoster virus (VZV), and Epstein-Barr virus (EBV). The following additional parameters were analyzed: gender, age, smoking, duration of dialysis, preexistent diabetes, and preexistent cardiovascular events. After 1 year posttransplantation cardiovascular events, body mass index, arterial hypertension, number of antihypertensive drugs, use of ACE and/or ARBs inhibitors, diabetes, anemia, homocysteine, creatinine, cholesterol, HDLc, LDLc, PTH-i, proteinuria, and immunosuppression with cyclosporine or tacrolimus. CMV replication was present in 79 (65.3%) patients. Among 121 renal transplant recipients, 13 presented cardiovascular events, all associated with CMV replication (P = .004). Neither HHV-6 or HHV-7 replication influenced this complication. All patients with these events were seropositive for CMV, HSV, VZV, and EBV, as opposed to 64.8% without them (P = .009). Other factors that showed differences between patients with versus without events were as follows: preexistent events (76.9% vs 14.8%; P = .000), age (60 +/- 10 vs 49 +/- 14; P = .002), serum triglyceride value (191 +/- 82 vs 135 +/- 72; P = .02), and anemia (23.1% vs 5.6%; P = .05). Multiple logistic regression analysis for statistically significant variables only showed that preexistent events influenced the development of posttransplantation events (odds ratio, 27; 95% confidence interval, 4.7-154; P = .0005). In conclusion, cardiovascular events within 1 year after transplantation were more frequent among patients with CMV replication and seropositivity for other herpesviruses. An important risk factor was the presence of preexistent events.

Hepatitis C virus reactivation in anti-hepatitic C virus-positive renal transplant recipients.

From 1992 to 2001 hepatitis C virus (HCV) viremia was studied in 53 renal transplant recipients anti-HCV+ with at least 3 months follow-up posttransplant using a quantitative retrotranscriptase-PCR method. HCV-RNA was detected in 45 (85%): 29 of the 34 recipients treated with azathioprine-based therapy and 15 of 18 treated with mycophenolate mofetil. Immunosuppressive therapy type did not affect HCV replication. Three different patterns of HCV-RNA evolution were detected: 13 (28.8%) patients with high RNA-HCV levels; 21 (46.7%) patients with low levels; and 11 (24.4%) patients with viremia elevation. In 10 (90%) of 11 of the last group, HCV viremia was detected before 15 days posttransplantation, significantly earlier than in the other two groups. Thus, replication during the first 15 days after transplantation leads to a high RNA-HCV viral load. No clinical symptoms were related to HCV.

Influence of ganciclovir prophylaxis on citomegalovirus, human herpesvirus 6, and human herpesvirus 7 viremia in renal transplant recipients.

In order to know the influence of ganciclovir (GCV) prophylaxis on cytomegalovirus (CMV) human herpesvirus (HHV)-6 and HHV-7 replication in renal transplant recipients, three groups were studies: 54 patients without GCV; 29, with short-term GCV prophylaxis (less than 30 days); and 51, with long-term GCV prophylaxis (more than 60 days). CMV viremia was more prevalent in the first group (74%, 55%, and 29%, respectively), but CMV replication was also found in 14 patients during therapy, in the other two groups. The antiviral did not affect the prevalence of HHV-6 (67.2%) or HHV-7 (76%), but HHV-6 viremia appeared later (42 +/- 31 vs 21 +/- 25/38 +/- 29 days posttransplant) and was shorter (29 +/- 30 vs 62 +/- 34/41 +/- 33 days) among patients with long-term GCV prophylaxis. On the other hand, CMV viremia was longer when HHV-6 replication was present (40 +/- 25 days vs 18 +/- 16 days). In addition, HHV-7 DNA was detected in all patients with CMV disease.

[Parvovirus B9 infection in a renal transplant recipient. Diagnosis by detection of viral genome in peripheral blood]. / Infección por parvovirus B19 en trasplante renal. Diagnóstico por detección del genoma viral en sangre periférica.

Parvovirus B19 can produce a picture known as pure red blood aplasia in recipients of solid organ. Occasionally the viruses cause decrease of the other blood cells, and various extra-hematologic manifestations. Common diagnosis is realised by bone marrow examination. The diagnostic value of the viral genome in the blood stream is not well defined. We reported the case of a male of 17 years of age, whose diagnosis was done by repeated determinations of the viral parvovirus B19 genome in peripheral blood. It was confirmed by a biopsy of the iliac crest. The patient was treated with unspecific IgG immunoglobulins, with complete recovery from the symptoms and signs. It did not have any recurrence of the disease. This case suggests that the realisation of PCR of Parvovirus B19 in renal transplant patients with pure red cell aplasia could be of greater interest in the diagnosis and monitoring of the disease. The detection of the viral genome could avoid the administration of unnecessary blood transfusions, and possibly the realization of bone marrow biopsy.

Cytomegalovirus antigenemia surveillance in the treatment of cytomegalovirus disease in AIDS patients.

OBJECTIVE: Surveillance of quantitative cytomegalovirus (CMV) antigenemia among AIDS patients with CMV treated complications in order to determine its value in assessing the response to treatment and survival. METHODS: A longitudinal follow-up of antigenemia measurement at diagnosis, after induction therapy with ganciclovir or foscarnet, and every 3 months during maintenance therapy was carried out in 25 patients with CMV retinitis and in 8 with extraocular CMV disease. Positive antigenemia was defined as the presence of any amount of immunofluorescent pp65-positive leukocytes/10(5) cells. RESULTS: Mean antigenemia values were: 77+/-148/10(5) leukocytes at retinitis diagnosis; 45+/-114 after induction therapy; and 7+/-18 and 1.5+/-4 after 6 months and one year of therapy, respectively. Patients achieving undetectable antigenemia increased from 44% at baseline to 68% at postinduction and 80% during follow-up. Seven patients (28%) who remained free of relapses presented significant minor baseline antigenemias and became negative after induction therapy. Patients with extraocular disease showed erratic antigenemia values and absent therapeutic response. CMV blood cultures before and after induction therapy were positive in 39% and 21% of patients, respectively. Kaplan-Meier analysis revealed a significantly longer survival for patients with retinitis when compared to those with extraocular complications, and for patients with negative antigenemia after induction in comparison with those who failed to achieve it. CONCLUSIONS: Low basal antigenemia and antigenemia clearance after induction therapy are variables directly related to good response to treatment and survival. Continuous surveillance of antigenemia during treatment could permit designing of individual strategies to obtain a better response.

Amplification of herpes simplex virus type 1 DNA in human geniculate ganglia from formalin-fixed, nonembedded temporal bones.

Polymerase chain reaction (PCR) has provided new insights in molecular biology. Recently, some studies have been focused on temporal bone pathology, with amplification of DNA from fixed sections of celloidin-embedded bones. The purpose of our study was to elucidate the utility of PCR in detection of minor concentrations of DNA from nonoptimal stored samples. We obtained geniculate ganglia from 30 temporal bones preserved in formalin for a long time, without any process of embedding. By performing a nested PCR assay, we detected herpes simplex virus type 1 DNA in 13 of 30 ganglia (43%). We conclude therefore that study of temporal bones stored under poor conditions by PCR is possible, although there are some limitations when compared with fresh or optimally archived samples.

Detection of herpes simplex virus-1 by nested PCR. An experimental model.

Nested polymerase chain reaction (nested PCR) was performed using a reaction mix batch-prepared and kept frozen in single reaction tubes at -20 degrees C until use. Twenty-one New Zealand white rabbits were infected with herpes simplex virus type 1 (HSV-1). Eleven animals were killed on day seven and the other ten were sacrificed on day 21. Viral culture and nested PCR was used to determine the presence of HSV-1 in samples from the tongue, HSV-1 was detected in 90.47% of the animals; in 84.21% by nested PCR and in 52.63% by culture. Nested PCR assay had greater sensitivity than culture in animals sacrificed on day seven with significative difference (p < 0.05). Higher sensitivity and faster results were obtained with this method, so we found it reliable and useful in the setting of a clinical laboratory dealing with diagnosis of herpes virus infections.

[Remission of severe disease induced by CMV and lymphoproliferative post-transplant disease after changing the immunosuppressive regime]. / Remisión de enfermedad severa por citomegalovirus y enfermedad linfoproliferativa post-trasplante en un receptor de trasplante renal tras terapia con ganciclovir y cambio en la medicación inmunosupresora.

We describe a renal transplant recipient, with overimmunosuppression induced by the interaction of tacrolimus and fluconazole, who developed two severe diseases produced by two different viruses of the herpes group (cytomegalovirus [CMV] disease and posttransplant lymphoproliferative [PTLD] disease EBV-related). Detection of Epstein-Barr virus (EBV) DNA in the blood preceded the histological diagnosis of PTLD. Both diseases improved after changes in the immunosuppressive regime and treatment with ganciclovir. Because CMV infection is a risk factor in developing PTLD, and the clinical and endoscopic manifestations of both diseases could be become confused, PTLD should be excluded in EBV seronegative patients that develop CMV disease. The detection of the EBV genome in blood could help in the early diagnosis of PTLD in these patients.

[Replication indexes of the human immunodeficiency virus: predictive value of viral culture and blood antigens]. / Indices de replicación del virus de la inmunodeficiencia humana: valor predictivo de los cultivos virales y de la antigenemia.

BACKGROUND: To investigate the relation between markers of load and replication of the HIV [viral culture in plasma and in mononuclear cells of peripheral blood (MCPB) and antigen p24 (p24Ag) with the number of CD4+ cells and the prognosis of the patients. METHODS: A retrospective study was performed in 188 patients who were analyzed and followed over a mean period of 431 days. The criteria of clinical progression (AIDS related complex, and new opportunistic infections), immunologic progression (CD4+ < 0.1 and < 0.05 + 10(9)/l) and death. Cocultures of HIV in free plasma and in MCPB were performed with the detection of complete AgHIV in the supernatant of the culture being used for analysis. Circulating p24Ag was determined by an ELISA technique without previous dissociation of the immunocomplexes. RESULTS: HIV cultures in plasma, in MCPB and p24Ag were positive in 27, 48 and 33% of the patients, respectively. The sensitivity of the indexes increased in agreement with the clinical progression of the patients and was inversely proportional to the depletion of the CD4+ lymphocytes (79% of the patients with CD4+ lymphocytes < 0.05 x 10(9)/l presented positive HIV culture in plasma). Viremia in plasma and to a lesser measure p24Ag correlated with variables recognized as bad prognosis and were found to be predictive of unfavorable evolution. Multivariate analysis demonstrated that pertenence to a symptomatic group and the presentation of a number of CD4+ lymphocytes of less than 0.2 x 10(9)/l were independent factors associated to the positivity of the viral culture in plasma and p24Ag. The culture positive in MCPB was principally related with the volume of blood analyzed. The risk of death was 6.38 fold greater in the presence of a positive plasma culture and 2.02 fold greater in the presence of positive p24Ag. In contrast, the unquantified positive HIV culture in MCPB showed no statistical significance in relation with patient survival. CONCLUSIONS: Positive HIV culture in plasma was the greatest prognostic index in patients with a number of CD4+ lymphocytes less than 0.2 x 10(9)/l. Unquantified cell culture had no predictive significance. To establish the prognosis of patients, the indexes of viral replication should not be used in isolation.

[Progressive multifocal leukoencephalopathy associated with human immunodeficiency virus infection: the clinical, neuroimaging, virological and evolutive characteristics in 35 patients]. / Leucoencefalopatía multifocal progresiva asociada a la infección por el virus de la inmunodeficiencia humana: características clínicas, de neuroimagen, virológicas y evolutivas de 35 pacientes.

BACKGROUND: The clinical, neuroimaging, virologic and evolutive characteristics of progressive multifocal leukoencephalopathy (PML) in 35 AIDS patients are studied. PATIENTS AND METHODS: PML was diagnosed by clinical and neuroimaging criteria in 32 patients and by autopsy in other three. The detection of JC virus (JCV) was done by PCR and further hybridization of the amplified DNA in peripheral blood lymphocytes, urine and CSF. RESULTS: 127 of 930 HIV positive patients were admitted by neuropsychiatric symptoms and of them 35 (SD 27.6%) by PML. The PML patients had a mean CD4 lymphocytes count of 75.3 (82.0)/x 10(6)/l and a HIV viral load of 330,698 (538,971) copies of RNA/ml. Thirty patients did not receive any anti-retroviral therapy or only transcriptase inhibitors monotherapy and five triple anti-retroviral therapy, including a proteases inhibitor. Multiple hypodense lesions on CT (53.1%) and T2 hyperintense lesions on MRI (58.3%) were the most frequent neuroimaging findings. JCV was detected in 20/21 (95.2%) LMP patients: 18/19 detections in lymphocytes, 6/8 in CSF and 4/6 in urine. The mean survival without and with antiretroviral therapy were 3.0 (0.47) and 21.4 (4.4) months (p < 0.001) in 34 patients followed. PML progressed to death in 31/34 patients (91.2%), and remained stable in 3/34 (8.8%). A patient was lost for follow-up. CONCLUSIONS: The application of clinical and neuroimaging criteria and the detection of JCV in CSF are useful for high presumption diagnosis of PML without brain biopsies. JCV detection in lymphocytes and in urine have a much lower predictive value. The evolution and survival of this disease can improve with triple anti-retroviral therapy including a protease inhibitor.

[The prognostic value of cytomegalovirus antigenemia and viremia for the development of cytomegalovirus disease and the survival of AIDS patients]. / Valor predictivo de la antigenemia y la viremia por citomegalovirus para el desarrollo de enfermedad por citomegalovirus y la supervivencia en pacientes con SIDA.

OBJECTIVES: To analyse risk factors for morbidity and survival associated with blood cytomegalovirus (CMV) detection with the antigenemia method among AIDS patients. PATIENTS AND METHODS: CMV antigenemia and CMV blood cultures in 277 AIDS patients IgG-CMV sero-positive with a CD4 level lower than 200 x 10(6)/l under antiretroviral monotherapy were analysed. We consider cases the 116 patients with one or more positive blood samples tested for pp65 antigenemia or CMV culture. They were matched with 161 control patients with negative antigenemia or viremia. RESULTS: Multivariate analysis pointed out a significant positive association for blood CMV reactivation with the following variables: CMV disease development and CMV urine detection, sex-acquired HIV infection, CD4+ < 50 x 10(6)/l and matched time from AIDS diagnosis to CMV blood culture correlated with positive antigenemias. Quantitative antigenemia title showed predictive value for risk of CMV disease although 23% of retinitis patients had persistent undetectable antigenemia. CMV invasive disease developed in 48% of cases and 11% of controls (relative risk [RR]: 7.9; 95% confidence interval [CI]: 4.2-14.7). Mortality after 12 months of follow-up was 73% vs 52% respectively (p < 0.001). Time survival curves after CD4+ count adjusting remained significantly lower for case patients (median, 127 days vs 355 days; p < 0.01 by log-rank test). Increased death rate was found in patients with CMV disease (74%), followed by patients with CMV antigenemia but no disease (70%) and patients without antigenemia or CMV disease (mortality 49%). CONCLUSIONS: CMV blood detection in AIDS patients may be considered as a bad prognosis marker for CMV morbidity and survival. This risk increases with higher CMV antigenemias. Therefore, pre-emptive anti-CMV therapy should be considered in this restricted population.

[The clinical significance of culturing Toxoplasma gondii on blood and other organic media]. / Significado clínico del cultivo de Toxoplasma gondii en sangre y en otros medios orgánicos.

BACKGROUND: The aim of this study was to determine the value of the Toxoplasma gondii culture in blood and in other organic fluids in HIV positive and negative patients. METHODS: Retrospective analysis (October 1990-May 1992) was carried out including all patients with positive cultures for T. gondii admitted to the Hospital Central of Asturias. The parasite was identified by monoclonal antibodies against the tachyzoite membrane. All patients with positive cultures were treated with pyrimethamine and sulphadiazine. RESULTS: Three hundred two samples from 256 patients, seropositive and seronegative for HIV, were analyzed. Of the seropositive group 8/45 (18%) had positive cultures for T. gondii versus 9/211 (4.3%) of the seronegative group (p = 0.002). Of the 19 positive samples, 15 were from blood, 3 from bronchoalveolar lavage and one from the vitreous fluid. Four out of 9 patients (44%) with AIDS and encephalic toxoplasmosis (ET) had blood cultures positive for T. gondii. Another 4 patients with AIDS presented toxoplasmenia without visceral involvement. Of the 9 HIV seronegative patients (3 immunodepressed patients), 4 had pulmonary toxoplasmosis, one ocular toxoplasmosis, and other clinical forms of toxoplasmosis were seen in the remaining 4. All the patients evolved to cure except 2 cases coinfected by cytomegalovirus who died. CONCLUSIONS: The identification of Toxoplasma gondii may be performed by blood cultures in half of the patients with AIDS and encephalic toxoplasmosis and in an undetermined percentage of the other clinical forms both in immunocompetent and immunodepressed subjects. In addition, toxoplasmemia has been registered in AIDS patients preceding any other organic seating of the parasite. Early antitoxoplasma therapy may, therefore, be effective.

Identification of the HSV-1 genome by "Dot Blot hybridization" in the geniculate ganglion of rabbits.

Herpes simplex Virus type 1 (HSV-1) was inoculated into 48 rabbits by 3 different routes: 10 rabbits were dosed by mouth, 18 rabbits injected in the tongue and 14 injected in the perineurium of the facial nerve at its entrance into the stylomastoid foramen. Some of the animals were killed after a week and others after three weeks. Facial palsy was produced in none of the cases. Seroconversion was demonstrated in the peripheral blood of 100% of the inoculated animals. Cultures of macerate of the facial nerve and geniculate ganglion, as well as of the ipsilateral medulla, were negative. DNA from HSV-1 was found by "Dot Blot hybridization" technique in 30% of the macerates of the geniculate ganglion and facial nerve and in 60% of the medulla macerate in those animals killed after one week and in 0% of both samples in those killed in the third week. The fact that the HSV-1 could be isolated in the geniculate ganglion of the facial nerve continues to support the possibility of this virus as the causal agent for facial palsy, either as a single disease or associated with other symptoms.

[Use of double PCR in an experimental mode of HSV-1 infection of the facial nerve]. / Utilización de la doble PCR en un modelo experimental de infección del nervio facial por el VHS-1*.

Recent studies suggested herpes simplex virus type 1 as a major etiologic factor in Bell's palsy. To analyze different aspects of facial nene infections, Swiss mice were inoculated with HSV-l in tongue (41 animals) and auricle (44). Nineteen mice developed unequivocal signs of nevous infection, but only in 1 mouse was evident a facial palsy. Mice were sacrificed at different intervals from inoculation, and facial nerves, Gasser ganglia and brain stem were obtained to test the presence of HSV-1 by nested PCR and viral culture. Virus was detected in the 3 types of samples, but identification was more frequent in animals injected in tongue and sacrificed during the acute infection. Nested PCR was far more sensitive than culture, particularly during viral latency. According with our results, HSV-1 could origin facial palsy, but is possible that lesions are immunomediated and localized at brain stem.

[Identification of respiratory syncytial virus and adenovirus in children with chronic serous otitis]. / Identificación del virus respiratorio sincitial y adenovirus en niños con otitis serosa crónica.

OBJECTIVE: To study the presence of respiratory syncytial virus (RSV) and adenovirus in the effusions of the middle ear and adenoid tissue from patients with chronic otitis media with effusion by use of the polymerase chain reaction. METHOD: The effusions and adenoid samples were collected from 32 children undergoing myringotomy and ventilation tube placement for chronic otitis media with effusion. The samples were separated for viral culture, immunofluorescence and PCR analysis. RESULTS: One (3%) effusion sample was positive for adenovirus by the PCR. None of samples (effusion and adenoid) were positives for RSV. The results of viral culture and immunofluorescence were all negative. CONCLUSIONS: Our results can not support that respiratory viruses play a role in the pathogenesis of chronic otitis media with effusion.

[Application of the polymerase chain reaction to an experimental model of infection by herpes simplex virus type 1]. / Aplicación de la reacción en cadena de la polimerasa a un modelo experimental de infección por el virus del herpes simplex tipo 1.

Herpes simplex type 1 (HSV-1) has been implicated as a cause of facial paralysis. We developed an experimental model in rabbits in which we injected HSV-1 into the tongue. The animals were killed after one and three weeks. The geniculate and trigeminal ganglia and medulla were extracted and the samples were processed. The polymerase chain reaction (PCR), nested-PCR and cultures were carried out in order to detect the viral genome in the samples. The viral genome was found in all but two rabbits. None of the animals developed clinical facial palsy. We conclude that nested PCR is more sensitive for the identification of HSV-1 in samples.