HIV-1 envelope glycoproteins isolated from viremic non-progressor individuals are fully functional and cytopathic

International audienc

BK virus infection in a pediatric renal transplant recipient

Fil: Bonaventura, Romina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología. Servicio de Neurovirosis; Argentina.Fil: Vázquez, A. Hospital de Niños de San Justo. Servicio de Nefrología; Argentina.Fil: Exeni, A. Hospital de Niños de San Justo. Servicio de Nefrología; Argentina.Fil: Rivero, K. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología. Servicio de Neurovirosis; Argentina.Fil: Freire, María Cecilia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología. Servicio de Neurovirosis; Argentina.El poliomavirus humano BK causa infección primaria asintomática en la niñez, estableciendo latencia principalmente en el tracto urinario. En individuos con alteración en la inmunidad celular se puede producir su reactivación desencadenando patología a nivel renal. Por estas razones es particularmente importante en la población pediátrica trasplantada renal, en la que puede producir la infección primaria cuando el paciente está inmunosuprimido. En nuestro trabajo se realizó el seguimiento de un paciente de 5 años trasplantado renal en octubre de 2003 que 45 días posttrasplante sufrió un deterioro del órgano injertado. Desde la fecha del trasplante hasta junio de 2004 se produjeron 3 episodios de alteración en la función renal, durante los cuales se analizaron muestras de sangre, orina, biopsia renal y líquido de linfocele. Para el diagnóstico difererencial entre rechazo agudo versus causa infecciosa se emplearon técnicas de detección para los virus BK, CMV y ADV, además del estudio citológico del tejido renal. Los resultados obtenidos junto con la clínica del paciente indican un probable caso de infección por BK. La importancia de realizar el diagnóstico diferencial entre rechazo agudo y la infección por BK radica en que la conducta en cuanto a la terapia inmunosupresora es opuesta en cada caso

BK virus infection in a pediatric renal transplant recipient

Fil: Bonaventura, Romina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología. Servicio de Neurovirosis; Argentina.Fil: Vázquez, A. Hospital de Niños de San Justo. Servicio de Nefrología; Argentina.Fil: Exeni, A. Hospital de Niños de San Justo. Servicio de Nefrología; Argentina.Fil: Rivero, K. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología. Servicio de Neurovirosis; Argentina.Fil: Freire, María Cecilia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Virología. Servicio de Neurovirosis; Argentina.El poliomavirus humano BK causa infección primaria asintomática en la niñez, estableciendo latencia principalmente en el tracto urinario. En individuos con alteración en la inmunidad celular se puede producir su reactivación desencadenando patología a nivel renal. Por estas razones es particularmente importante en la población pediátrica trasplantada renal, en la que puede producir la infección primaria cuando el paciente está inmunosuprimido. En nuestro trabajo se realizó el seguimiento de un paciente de 5 años trasplantado renal en octubre de 2003 que 45 días posttrasplante sufrió un deterioro del órgano injertado. Desde la fecha del trasplante hasta junio de 2004 se produjeron 3 episodios de alteración en la función renal, durante los cuales se analizaron muestras de sangre, orina, biopsia renal y líquido de linfocele. Para el diagnóstico difererencial entre rechazo agudo versus causa infecciosa se emplearon técnicas de detección para los virus BK, CMV y ADV, además del estudio citológico del tejido renal. Los resultados obtenidos junto con la clínica del paciente indican un probable caso de infección por BK. La importancia de realizar el diagnóstico diferencial entre rechazo agudo y la infección por BK radica en que la conducta en cuanto a la terapia inmunosupresora es opuesta en cada caso

Characterization of Streptococcus pneumoniae clones from paediatric patients with cystic fibrosis

The role ofStreptococcus pneumoniaein cystic fibrosis (CF) is poorly understood. The pneumococcal population has changed over time after the introduction of the heptavalent conjugate vaccine (PCV7) and, more recently, the 13-valent conjugate vaccine (PCV13). Although serotypes and clones causing invasive pneumococcal disease or colonizing healthy children have been extensively analysed, little is known so far on the serotypes and clones of pneumococci in CF patients. The aim of this work was to investigate serotypes, antibiotic susceptibilities, genotypes and biofilm production of CF pneumococcal isolates. Overall, 44S. pneumoniaestrains collected from 32 paediatric CF patients from January 2010 to May 2012 in a large Italian CF Centre were tested for antimicrobial susceptibility testing by Etest, serotyped by the Quellung reaction and genotyped by a combination of different molecular typing methods, includingpbpgene restriction profiling,pspArestriction profiling and sequencing, PFGE and multilocus sequence typing. Biofilm production by pneumococcal strains was also assessed. Penicillin non-susceptibility was 16 %. High resistance rates (>56 %) were observed for erythromycin, clindamycin and tetracycline. The most frequent serotype recovered was serotype 3 (31.8 %). The coverage of PCV7 and PCV13 was 6.8 and 47.7 %, respectively. More than 80 % of CF strains belonged to Pneumococcal Molecular Epidemiology Network (PMEN) reference clones, the most common being Netherlands3-ST180 (28.2 %), and Greece21-30/ST193 (15.4 %). All strains produced biofilmin vitro, although with large variability in biofilm formation efficiency. No correlation was found between biofilm levels and serotype, clone or antibiotic resistance. The high isolation rate of antibiotic-resistant serotype 3 pneumococci from CF patients suggests that PCV13 could increase protection from pneumococcal colonization and infection

Antigenic and molecular characterization of rabies virus in Argentina

Fil: Cisterna, Daniel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirus; Argentina.Fil: Bonaventura, Romina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirus; Argentina.Fil: Caillou, Susana. División de zoonosis; Tucuman, Argentina.Fil: Pozo, Oscar. Ministerio de Salud. División de Zoonosis Urbana; Argentina.Fil: Andreau, Maria Lidia. Laboratorio Regional de Diagnóstico de Rabia; Chaco, Argentina.Fil: Dalla Fontana, María L. Laboratorio de Zoonosis; Santa Fe, Argentina.Fil: Echegoyen, Cristina. Dirección Nacional de Epidemiología; Argentina.Fil: de Mattos, Carlos. Centers for Desease Control and Prevention. Rabies Section; Estados Unidos.Fil: de Mattos, Cecilia. Centers for Desease Control and Prevention. Rabies Section; Estados Unidos.Fil: Russo, Susana. Servicio Nacional de Sanidad y Calidad Agroalimentaria. Dirección de Laboratorios y Control Técnico; Argentina.Fil: Novaro, Laura. Servicio Nacional de Sanidad y Calidad Agroalimentaria. Dirección de Laboratorios y Control Técnico; Argentina.Fil: Elberger, Diana. Servicio Nacional de Sanidad y Calidad Agroalimentaria. Dirección de Laboratorios y Control Técnico; Argentina.Fil: Freire, María Cecilia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirus; Argentina.The nucleoprotein genes of 54 human, domestic and wild animals rabies isolates obtained in Argentina between 1995 and 2002 were characterized using monoclonal antibodies and partial gene sequence analysis. The antigenic and genetic diversities of rabies virus in samples from bat and bat-related cases were studied, leading to the identification of five distinct genetic variants. Rabies viruses isolated from vampire bat related cases were very similar to each other, showing 98.9% overall similarity. Specific antigenic variants (AgV) were detected associated with different insectivorous bats species, in samples from Tadarida brasiliensis and Eumops patagonicus bats. In contrast, isolates from Myotis sp. and Histiotus sp. bats could not be matched to any antigenic type. Additionally, bat rabies cases were also detected in southern provinces previously considered rabies-free. Finally, two independent antigenic and genetic variants co-circulating in northern Argentina were found in isolates obtained from dogs and dog-related cases, suggesting two independent cycles of virus transmission. This is the first national coordinated study of antigenic as well as molecular epidemiology of rabies in Argentina. The information presented here will improve our knowledge about rabies epidemiology and therefore, will assist preventing fatal human cases

Evaluation of RT-qPCR and Loop-Mediated Isothermal Amplification (LAMP) Assays for the Detection of SARS-CoV-2 in Argentina

Our aim was to evaluate the analytical and clinical performance of the SARS-CoV-2 molecular detection kits used in Argentina. Nine real-time reverse-transcription polymerase chain reaction (RT-qPCR) and three reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assays were evaluated using the World Health Organization (WHO) recommended test as reference method. A secondary standard calibrated for the E, N and RdRp genes against the Pan American Health Organization—World Health Organization—International Standard was used to calculate the limit of detection (LoD). A panel of artificial clinical samples, 32 positive and 30 negative for SARS-CoV-2, were analyzed to estimate the kappa concordance (κ) and the diagnostic performance. Differences among the LoD values for the target genes amplified by each kit were >1 log copies/reaction. The κ for the RT-qPCR kits was greater than 0.9, whereas that for the RT-LAMP assays ranged from 0.75 to 0.93. The clinical performance of RT-qPCR kits showed 100% specificity and high sensitivity, although with variations according to the gene analyzed. The E and N genes provided greater clinical sensitivity, whereas the RdRp gene increased the clinical specificity. The RT-LAMP assays revealed a variable diagnostic performance. The information provided can be useful to choose the most appropriate diagnostic test and may contribute to the establishment of a consensus in the diagnosis of SARS-CoV-2 in Argentina and the region

Population pharmacokinetics and pharmacogenetics of ritonavir-boosted darunavir in the presence of raltegravir or tenofovir disoproxil fumarate/emtricitabine in HIV-infected adults and the relationship with virological response : a sub-study of the NEAT001/ANRS143 randomized trial

OBJECTIVES: NEAT001/ANRS143 demonstrated non-inferiority of once-daily darunavir/ritonavir (800/100 mg) + twice-daily raltegravir (400 mg) versus darunavir/ritonavir + tenofovir disoproxil fumarate/emtricitabine (245/200 mg once daily) in treatment-naive patients. We investigated the population pharmacokinetics of darunavir, ritonavir, tenofovir and emtricitabine and relationships with demographics, genetic polymorphisms and virological failure. METHODS: Non-linear mixed-effects models (NONMEM v. 7.3) were applied to determine pharmacokinetic parameters and assess demographic covariates and relationships with SNPs (SLCO3A1, SLCO1B1, NR1I2, NR1I3, CYP3A5*3, CYP3A4*22, ABCC2, ABCC10, ABCG2 and SCL47A1). The relationship between model-predicted darunavir AUC0-24 and C24 with time to virological failure was evaluated by Cox regression. RESULTS: Of 805 enrolled, 716, 720, 347 and 361 were included in the darunavir, ritonavir, tenofovir and emtricitabine models, respectively (11% female, 83% Caucasian). No significant effect of patient demographics or SNPs was observed for darunavir or tenofovir apparent oral clearance (CL/F); coadministration of raltegravir did not influence darunavir or ritonavir CL/F. Ritonavir CL/F decreased by 23% in NR1I2 63396C>T carriers and emtricitabine CL/F was linearly associated with creatinine clearance (P < 0.001). No significant relationship was demonstrated between darunavir AUC0-24 or C24 and time to virological failure [HR (95% CI): 2.28 (0.53-9.80), P = 0.269; and 1.82 (0.61-5.41), P = 0.279, respectively]. CONCLUSIONS: Darunavir concentrations were unaltered in the presence of raltegravir and not associated with virological failure. Polymorphisms investigated had little impact on study-drug pharmacokinetics. Darunavir/ritonavir + raltegravir may be an appropriate option for patients experiencing NRTI-associated toxicity