A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts.

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10-5 ). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.

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.

Detection of cytomegalovirus in bronchoalveolar lavage fluid from immunocompromised patients with pneumonitis by viral culture and DNA quantification.

PURPOSE: To compare the detection of human cytomegalovirus (HCMV) in bronchoalveolar lavage (BAL) fluid by viral culture and quantitative polymerase chain reaction (qPCR), and to establish a viral load threshold that can identify cases of HCMV replication indicative of pneumonitis. There is currently no universal viral load cut-off to differentiate between patients with and without pneumonitis, and the interpretation of qPCR results is challenging. METHODS: 176 consecutive BAL samples from immunosuppressed hosts with signs and/or symptoms of respiratory infection were prospectively studied by viral culture and qPCR. RESULTS: Concordant results were obtained in 81.25% of the BAL samples. The rest were discordant, as only 34% of the qPCR-positive BAL samples were positive by culture. The median HCMV load was significantly higher in culture-positive than in culture-negative BAL samples (5038 vs 178 IU/mL). Using a cut-off value of 1258 IU/mL of HCMV in BAL, pneumonia was diagnosed with a sensitivity of 76%, a specificity of 100%, a VPP of 100% and VPN of 98%, and HCMV was isolated in 100% of the BAL cultures. CONCLUSION: We found that a qPCR-negative was a quick and reliable way of ruling out HCMV pneumonitis, but a positive result did not always indicate clinically significant replication in the lung. However, an HCMV load in BAL fluid of ≥ 1258 IU/mL was always associated with disease, whereas < 200 IU/mL rarely so.

[Prophylactic and pre-emptive therapy for cytomegalovirus infection in kidney transplant patients using oral valganciclovir]. / Tratamiento profiláctico y anticipado de la infección por citomegalovirus en pacientes trasplantados renales mediante valganciclovir oral.

UNLABELLED: Prophylactic and pre-emptive therapy with oral valganciclovir for cytomegalovirus infection in renal transplant recipients. BACKGROUND: Cytomegalovirus infection is a very important health problem in solid organ transplant recipients (SOT). Once-daily valganciclovir has been shown to be as clinically effective and well tolerated as oral ganciclovir tid in the prevention of CMV infection in high risk SOT recipients. METHODS: The aim of the present study was to evaluate the incidence and severity of CMV disease in 150 renal transplant recipients that received either prophylactic [high risk group (HR), N = 66] or pre-emptive [low risk group (LR), N = 84] therapy with oral valganciclovir (900 mg/day vo) for three months according to their basal risk. Patients were monitored for signs and symptoms of CMV disease and CMV plasma viral load was assessed weekly. RESULTS: A total of 31 patients (47%) of the HR and 26 patients (31%) of the LR presented a positive CMV PCR result. Twelve patients (14.3%) in the LR that had a high viral load (CMV PCR > 1,000 copies/mL) but remained asymptomatic received pre-emptive therapy. Four patients (4.7%) in the LR, after an average time of 35 days after transplant and two patients (4.5%) in the HR, after prophylactic treatment was completed, developed CMV disease. The disease was mild-moderate in most of the cases. Those patients that developed CMV disease responded to treatment with iv ganciclovir for 14 days followed by treatment with oral valganciclovir for up to three months. CONCLUSION: Prophylactic treatment with oral valganciclovir for CMV prevention is only required in high risk solid organ transplant recipients.

Relation between pp65 antigenemia, RT-PCR and viruria for cytomegalovirus detection in kidney transplant recipients.

INTRODUCTION: We compared the efficiency of detection using pp65 antigenemia, reverse transcription-polymerase chain reaction (RT-PCR), and viruria for the diagnosis of cytomegalovirus (CMV) infections after kidney transplantation. PATIENTS AND METHODS: We evaluated 40 renal transplant recipients between weeks 5 and 12 after transplantation, including 179 blood and 181 urine specimens. RESULTS: All positive samples by antigenemia were also positive by PCR. However, in 52 cases only PCR was positive (kappa = 0.134 [P < .001]). Viruria was positive in 66 cases, but only 26 were CMV PCR positive. In 34 cases, viruria was negative and PCR positive (P = .192). CONCLUSION: Detection of DNA in serum is a more sensitive method than antigenemia for the diagnosis of CMV infection. Viruria was not related to the presence of CMV in blood.

Impact of Epstein Barr virus-related complications after high-risk allo-SCT in the era of pre-emptive rituximab.

We monitored 133 high-risk allo-SCT recipients for 6 months after transplant for EBV reactivation by quantitative real-time PCR. Rituximab was given as pre-emptive therapy for viremia >1000 copies/mL. The 1-year cumulative incidence of EBV reactivation was 29.4% (95% confidence interval (CI): 18-40) in patients monitored due to initial high-risk characteristics (n=93) and 31.8% (95% CI: 19.7-44) in those followed because of the development of refractory GVHD (n=40). Overall response rate to Rituximab was 83%. Nine patients (9.6%) developed post-transplant lymphoproliferative disorder (PTLD) at a median of +62 days after SCT. Eight of them showed a concomitant CMV reactivation. Second SCT was the only risk factor associated with EBV infection and PTLD in multivariate analysis (hazard ratio (HR) 2.6 (95% CI: 1.1-6.4; P=0.04) and HR 6.4 (95%CI: 1.3-32; P=0.02)). The development of EBV reactivation was not associated with non-relapse mortality or OS (P=0.97 and P=0.84, respectively).

Antiviral susceptibility of Herpes simplex viruses and its clinical correlates: a single center's experience.

The in vitro susceptibility to acyclovir of 204 herpes simplex virus isolates from 165 immunocompromised patients treated at our hospital was determined by the cytopathic effect reduction assay. Approximately 95% of herpes simplex virus 1 and 73% of herpes simplex virus 2 isolates were inhibited by acyclovir at concentrations of <2 microgram/mL. From 8 patients (5%), an isolate with low susceptibility to acyclovir (50% inhibitory dose, >3 microgram/mL) was recovered. Medical records of 83 patients were reviewed. Lesions resolved in most of the patients, independent of treatment. Treatment failures were not always associated with isolation of an in vitro-resistant virus. On the contrary, when a virus with low susceptibility to acyclovir was isolated, resolution of the lesion was the rule. In 9 of 10 patients with subsequent recurrent episodes of disease, the susceptibility of the viruses isolated was similar to that of the first episode. Routine susceptibility testing in our geographic area is not encouraged because of the low incidence of acyclovir-resistant herpes simplex viruses.

Cytomegalovirus pp65 antigenemia-guided pre-emptive treatment with ganciclovir after allogeneic stem transplantation: a single-center experience.

The optimal prophylactic strategy for cytomegalovirus (CMV) disease after allogeneic hematopoietic stem cell transplantation has not yet been established. The aim of this study was to analyze our single-center experience with a uniform protocol of CMV antigenemia-guided pre-emptive treatment with ganciclovir (GCV) after allografting. Fifty-two consecutive adult patients, 48 of them transplanted from HLA-identical matched related donors were included. T cell-depleted marrow or peripheral blood were used in 21 cases. After engraftment, weekly blood samples were tested for CMV pp65 antigenemia and viremia (conventional cultures) until day +100. GCV was started if CMV antigenemia and/or CMV viremia were detected. CMV infection (CMV-I) was found in 19 patients (37%). Seven patients suffered from CMV disease (CMV-D), three colitis and four pneumonias. There was one death directly related to CMV-D and three further cases died from refractory GVHD with CMV-D. Only one patient developed CMV pneumonia without any previous positive antigenemia and/or viremia. Multivariate analysis identified grades II-IV acute GVHD (P = 0.02) and peripheral blood stem cell transplantation (P = 0.03) to be risk factors for developing CMV-I. In conclusion, this monitoring protocol allowed early treatment of CMV-I without progression to CMV-D. Pre-emptive therapy had the additional advantage of avoiding GCV administration in most of our allograft recipients.

Pulmonary enterovirus infections in stem cell transplant recipients.

In recent years, it has been recognised that the community respiratory viruses are a frequent cause of upper and lower respiratory tract infections in immunocompromised hosts such as bone marrow transplant recipients. By contrast, infections by non-polio enteroviruses have rarely been reported after stem cell transplantation. We present four cases of acute respiratory illness with enterovirus isolated as the sole pathogen from bronchoalveolar lavage. All four patients developed pneumonia and three died of progressive pneumonia, which reflects the severity of this complication. We conclude that enteroviral pulmonary infections may be a cause of severe pneumonia in immunocompromised hosts.

Thrombocytopenia associated with liver cirrhosis and hepatitis C viral infection: role of thrombopoietin.

BACKGROUND/AIMS: Thrombocytopenia in chronic liver diseases has traditionally been considered a consequence of platelet pooling and destruction in spleen. We tried to evaluate the influence of thrombopoietin, the physiological regulator of thrombopoiesis, on the origin of this thrombocytopenia. METHODOLOGY: We determined serum thrombopoietin levels by ELISA in thrombocytopenic patients with liver cirrhosis (n = 32) and with chronic hepatitis C viral infection (n = 23). A group of 43 healthy subjects was used as a control. RESULTS: Liver cirrhosis patients presented slightly, but not significantly, lower serum thrombopoietin levels (104 +/- 56 pg/mL) than controls (121 +/- 58 pg/mL) or patients infected with chronic hepatitis C virus (125 +/- 40 pg/mL). No correlations were found between serum thrombopoietin concentrations and liver tests or hematological parameters. CONCLUSIONS: We conclude that low thrombopoietin production may play a role, along with hypersplenism, in the development of thrombocytopenia in patients with liver cirrhosis. Normal thrombopoietin levels exclude a defect in thrombopoietin production as a possible etiology for the thrombocytopenia in patients with chronic hepatitis C viral infection. However, a direct viral megakaryocyte infection or an immune mechanism could explain this thrombocytopenia, according to the thrombopoietin levels detected.

[In vitro susceptibility to ganciclovir and foscarnet of cytomegaloviruses]. / Sensibilidad in vitro de citomegalovirus al ganciclovir y al foscarnet.

Ganciclovir is the drug of choice for the treatment of acute cytomegalovirus infections. This antiviral agent is a nucleoside analog of guanine whose activity is dependent upon its intracellular phosphorylation to the triphosphate derivative. Foscarnet is used to treat immunosuppressed patients such as organ transplant recipients and AIDS patients with cytomegalovirus who do not tolerate or develop resistance to ganciclovir. Foscarnet is a pyrophosphate analog that directly inhibits viral DNA polymerase. Resistant isolates have been recovered from immunocompromised patients treated with both anticytomegalovirus compounds. The aims of this study were to prepare a plaque reduction assay to study the in vitro susceptibility of cytomegalovirus to ganciclovir and foscarnet, and to apply it to the knowledge of in vitro susceptibility values of cytomegalovirus isolated from clinical samples. Eighty isolates from patients who had never been treated with ganciclovir or foscarnet were tested for antiviral susceptibility. The plaque reduction assay took 6-8 weeks. The results are expressed as ID(50) (inhibitory dose 50), and the ID(50) values of ganciclovir were between 2.14 and 13.49 microM. The ID(50) for ganciclovir was higher that 12 microM in only two cases (2%). The molecular study of the DNA of these did not show any mutation in the UL97 gene. The ID(50) values of foscarnet were between 46.65 and 460.22 microM. In 78 cases (98%) foscarnet ID(50) was lower than 400 microM. These results were comparable with those obtained by other authors. To summarize, the frequency of cytomegalovirus strains resistant in vitro to ganciclovir and foscarnet in previously untreated patients was low and when it was present it did not involve therapeutic failure since the patients progressed favorably.

[Clinical utility of susceptibility testing of herpes simplex virus to acyclovir]. / Utilidad clínica del estudio de la sensibilidad al aciclovir de los virus herpes simple.

In vitro susceptibility to acyclovir of 96 strains of herpes simplex virus isolated from 80 immunocompromised patients attended in our hospital was studied by the cytopathic effect reduction assay. Ninety-eight percent (61/62) of herpes simplex virus 1 strains and 91% (31/34) of herpes simplex virus 2 strains were inhibited by acyclovir concentrations lower than 3 mg/l. In 5% of the patients herpes simplex strains resistant to acyclovir (ID(50) >3 mg/l) were isolated. Ninety-eight percent of the lesions caused by herpes simplex viruses susceptible to acyclovir (ID(50) <3 mg/l) resolved independently of treatment. In two cases, the cytopathic effect reduction assay was not able to predict treatment failure and persistance of the lesions was not always associated with isolation of a resistant strain in vitro. In four cases, isolation of a strain resistant to acyclovir was not indicative of treatment failure. In conclusion, we believe there is no need to routinely test susceptibility of herpes simplex viruses to acyclovir and that susceptibility testing should be indicated only in patients in whom lesions persist and other causes have been ruled out.

[Detection of early cytomegalovirus antigen in cell culture]. / Detección de antígeno temprano de citomegalovirus en cultivo celular.

The reference technique for the diagnosis of active cytomegalovirus infection is the isolation in cellular culture. Its major drawback is the interval between the inoculation of the sample and the development of the characteristic cytopathic effect. Occasionally, this delay may be longer than four weeks. The centrifugation of the sample on the cell monolayer at the time of inoculation and the use of a fluorescein-labeled monoclonal antibody for the detection of the early antigen in cells may considerable reduce the time required for the diagnosis of cytomegalovirus infection. In the present study the technique of detection of the early antigen by immunofluorescence was compared with conventional cell culture in 258 clinical samples referred to the laboratory for study. Fifty-one of them were positive: 28 with both techniques, 12 only with cell culture and 11 only with immunofluorescence. The mean time to obtain positive results was 25 hours for immunofluorescence and 13 days for culture.

[Prevalence of human immunodeficiency virus infection and behaviors associated with its transmission among parenteral drug users selected on the street]. / Prevalencia de infección por el virus de la inmunodeficiencia humana y de los comportamientos asociados a su transmisión entre usuarios de drogas por vía parenteral seleccionados en la calle.

BACKGROUND: To estimate the prevalence of HIV infection and the associated risk behaviours among intravenous drug users not receiving treatment for their drug dependence. PATIENTS AND METHODS: A cross-sectional study of 200 intravenous drug users recruited from the streets of Barcelona in 1993. Information about the socio-demographic aspects and behaviours was obtained through a personal interview using a standardised questionnaire which was carried out by three ex-drug users. Saliva samples were used to determine anti HIV antibodies. RESULTS: The prevalence of HIV infection was 51%. 57% borrowed used syringes, 65% lended their syringes, and 41% practised back of frontloading. 85% if those who shared syringes always cleaned them, however 59% only used water. 78% had heterosexual relations, in 33% of the cases with a non-injecting sexual partner. 65% always used condoms with sexual clients although only 26% always used them with stable sexual partners and 36% with casual sexual partners. 78% had performed the HIV test and among those who knew they were seropositive, 40% had received some kind of health control in the last 6 months. Not having a legal income, injecting speedball or barbiturates, unknowing self HIV negative status and practicing forms of indirect sharing were found to be independently associated with syringe sharing. CONCLUSIONS: The high prevalence of HIV infection and associated risk behaviours highlights the need to increase and adapt the prevention efforts and investigation to this group. Social marginalization and poliuse of drugs should be addressed in HIV prevention programs.

[Abdominal pain as the initial symptom of visceral varicella zoster infection in hematopoietic stem cell transplant recipients]. / Dolor abdominal como forma de presentación de infección visceral por el virus varicela zoster en receptores de transplante de progenitores hematopoyéticos.

Varicella zoster virus (VZV) infections are an important cause of morbidity after stem cell transplantation (SCT), with no differences in their overall incidence between allogeneic and autologous transplants. We report four patients who developed a disseminated VZV infection with visceral involvement after an allogeneic (n = 3) or autologous (n = 1) SCT. In all 4 cases, the initial symptom was severe abdominal pain which preceded the appearance of the classical herpetic vesicular skin lesions from two to four days in three cases, while one never developed skin lesions. The interval from the transplant to the infection ranged from 5 to 13 months, and all three allogeneic SCT received a T-cell depleted graft, although two suffered from chronic GVHD. All patients had clinical, radiologic and/or biochemical findings indicative of gastrointestinal or visceral involvement. An extensive bibliography review of this specific form of presentation of disseminated VZV infection is presented. The interval from the abdominal pain to the development of the skin lesions has ranged from one to 10 days, and this has led to a delay in the initiation of specific antiviral therapy in many cases, including our only fatal case. We conclude that an abdominal pain of unknown origin in this particular clinical setting should always be regarded as a possible prodromal phase of a disseminated VZV infection.

[Isolation, sequencing and ultrastructure of HTLV-I and HTLV-II retroviruses. Presence of the HTLV-II subtype b among Spanish intravenous drug addicts]. / Aislamiento, secuenciación y ultraestructura de los retrovirus HTLV-I y HTLV-II. Presencia del HTLV-II subtipo b entre adictos a drogas por vía parenteral españoles.

BACKGROUND: Six cases of HTLV-I/II infection were selected for isolation and characterization of these retrovirus. METHODS: Detection of anti-HTLV antibodies was carried out by enzyme immunoassay (EIA), immunofluorescence (IFI), and Western blot (WB). Analysis of proviral DNA was performed by PCR. Viral culture and partial sequencing of the pol and pX genes were carried out. Electron microscopy morphologically characterized the viral particles. RESULTS: Serologic study demonstrated four cases of HTLV-II, one of HTLV-I, and one non-typeable HTLV infections. This last case was confirmed as positive for HTLV-II by PCR. Five new HTLV-II and one HTLV-I infected cell lines have been established by co-culture. Electron microscopy allowed morphologic characterization of the viral particles found in the infected cells. The sequence of the five strains of HTLV-II was identical demonstrating a divergence of 0.49% in the pX region and of 4.5% in the pol region compared with the HTLV-II Mo prototype. Comparison of these sequences with those corresponding to different strains of HTLV-II isolates from American Indians (subtypes b) suggest that these Spanish strains are more closely related with the subtype b than with the subtype a (HTLV-II Mo). Genetic variability study did not reveal any change in the sequence of these stains suggesting that the variability of these retroviruses in very infrequent in the regions studied. The analysis of the pol region of the HTLV-I strain demonstrated a divergence of 3.4% with respect to the sequence of the ATK-1 prototype (Japan) and of 1.7% of the strain HS-35 (Caribbean) showing a greater relation with the Caribbean strains than with those from Japan. CONCLUSIONS: The presence of HTLV-II subtype has been confirmed among intravenous drug addicts in Spain. Isolation and characterization of the HTLV-I strain demonstrated that this also circulating around Spain despite its South American origin.

[Mucocutaneous manifestations in acute HIV infection. 3 case reports]. / Manifestaciones mucocutáneas en la infección aguda por el VIH. Presentación de tres casos.

We report three patients who developed a generalized rash with oral, genital or perianal ulcerations as a result of acute infection due to HIV. The primary infection was diagnosed by seroconversion (by means of EIA and Western blot techniques). Definitive diagnosis was established on days 52, 85 and 97 after the appearance of the rash. The p24 protein of the HIV was only detected in the early phase of the disorder in the two cases in which this study was carried out.

Enteroviruses in Spain over the decade 1998-2007: virological and epidemiological studies.

BACKGROUND: Human enteroviruses (HEV) are the commonest cause of viral meningitis as well as other pathologies, therefore HEV characterization is important both in patient management and epidemiological investigation. OBJECTIVES: A 10-year study of patients with enteroviral infection was carried out in Spain to determine the underlying etiology. STUDY DESIGN: HEV were fully typed by microneutralisation tests and/or molecular methods. RESULTS: A collection of 86404 clinical samples were studied in several Spanish laboratories. These were collected from patients with different syndromes, mainly aseptic meningitis (AM), fever, respiratory diseases and acute flaccid paralysis. Of these, 6867 HEV were obtained. At the National Poliovirus Laboratory 2814 were serotypically characterised. Among non-polio enteroviruses, the eight main serotypes were Echovirus 30 (25%), Echovirus 6 (12.4%), Echovirus 13 (8.3%), Echovirus 11 (7.4%) and Echovirus 9 (4.7%), followed by Coxsackievirus B5 (4.2%) and Echovirus 7 and Coxsackievirus A9 (3.7%) each. In AM cases, Echovirus 30 was identified in 39% of them, followed by Echovirus 6 (14%). However, Echovirus 6 was mainly associated with respiratory disease (17%), followed by Echovirus 11 (10%). On the other hand, Echovirus 30, Echovirus 11 and Echovirus 6 contributed equally with 12% of each serotype in the cases of fever. CONCLUSIONS: The present report complements previous data (Trallero et al.(13)), with the results of HEV incidence in Spain from 1998 to 2007. The surveillance described in this study provided valuable information as to which serotypes are in circulation, the emergence of new HEV and association with clinical manifestations.