Validación de un kit comercial (diagnóstico del síndrome de Gilbert) para la determinación del polimorfismo ugt1a1*28 (intolerancia al irinotecan): evaluación de su implementación en la práctica asistencial.

El irinotecán es un medicamento utilizado en primera línea del cáncer colorrectal metastásico (habitualmente en combinación con fluorouracilo). La FDA incluyó en el año 2017 como biomarcador genómico pronóstico de toxicidad las variantes en el gen UGT1A1. Los pacientes portadores en heterocigosis del alelo UGT1A1*1/*28 y en homocigosis UGT1A1*28/28 presentan una actividad reducida de la enzima. Es por ello que se recomienda la determinación de las variantes de la familia UGT1A1 en pacientes en tratamiento con irinotecán. Existe asociación entre pacientes con el alelo UGT1A1*28 y disminución de la expresión de UGT1A1 y, en consecuencia, disminución de la glucuronidación de SN-38. La disminución de UGT1A1 se asocia con riesgo elevado (aproximadamente 4 veces) de toxicidad severa con irinotecán, incluyendo diarrea y neutropenia. De ahí la necesidad de implementar la utilización de un kit comercial para su uso en la práctica clínica asistencial garantizando la veracidad de los resultados. Para ello, se ha realizado una validación-verificación de un kit comercial inicialmente destinado para el diagnóstico de Síndrome de Gilbert para su aplicación en el estudio genético del polimorfismo UGT1A1*28: intolerancia al irinotecán y sus metabolitos. Asimismo, se han evaluado estadísticamente los resultados de la implementación del uso de dicho kit en la práctica asistencial y la frecuencia del polimorfismo en heterocigosis y homocigosis en la población a estudio durante un periodo de unos 4 meses desde su uso para diagnóstico en muestras de pacientes.Los resultados obtenidos han tenido una concordancia del 100% (intra e inter-laboratorio) y permiten asegurar que el Kit EXPERTEAM está validado y verificado y puede emplearse para el estudio de la presencia del polimorfismo A(TA)7TAA en el gen UGT1A1. Además, de los 79 pacientes que han conformado el estudio, se ha concluido que el 18% presentan el polimorfismo heterocigoto, el 37% homocigotos, y el 45% eran normales. <br /

Quorum sensing network in clinical strains of A. baumannii : AidA is a new quorum quenching enzyme

Acinetobacter baumannii is an important pathogen that causes nosocomial infections generally associated with high mortality and morbidity in Intensive Care Units (ICUs). Currently, little is known about the Quorum Sensing (QS)/Quorum Quenching (QQ) systems of this pathogen. We analyzed these mechanisms in seven clinical isolates of A. baumannii. Microarray analysis of one of these clinical isolates, Ab1 (A. baumannii ST-2-clon-2010), previously cultured in the presence of 3-oxo-C12-HSL (a QS signalling molecule) revealed a putative QQ enzyme (α/β hydrolase gene, AidA). This QQ enzyme was present in all nonmotile clinical isolates (67% of which were isolated from the respiratory tract) cultured in nutrient depleted LB medium. Interestingly, this gene was not located in the genome of the only motile clinical strain growing in this medium (A. baumannii strain Ab421-GEIH-2010 [Ab7], isolated from a blood sample). The AidA protein expressed in E. coli showed QQ activity. Finally, we observed downregulation of the AidA protein (QQ system attenuation) in the presence of HO (ROS stress). In conclusion, most of the A. baumannii clinical strains were not surface motile (84%) and were of respiratory origin (67%). Only the pilT gene was involved in surface motility and related to the QS system. Finally, a new QQ enzyme (α/β hydrolase gene, AidA protein) was detected in these strains

Subcutaneous anti-COVID-19 hyperimmune immunoglobulin for prevention of disease in asymptomatic individuals with SARS-CoV-2 infection: a double-blind, placebo-controlled, randomised clinical trialResearch in context

Summary: Background: Anti-COVID-19 hyperimmune immunoglobulin (hIG) can provide standardized and controlled antibody content. Data from controlled clinical trials using hIG for the prevention or treatment of COVID-19 outpatients have not been reported. We assessed the safety and efficacy of subcutaneous anti-COVID-19 hyperimmune immunoglobulin 20% (C19-IG20%) compared to placebo in preventing development of symptomatic COVID-19 in asymptomatic individuals with SARS-CoV-2 infection. Methods: We did a multicentre, randomized, double-blind, placebo-controlled trial, in asymptomatic unvaccinated adults (≥18 years of age) with confirmed SARS-CoV-2 infection within 5 days between April 28 and December 27, 2021. Participants were randomly assigned (1:1:1) to receive a blinded subcutaneous infusion of 10 mL with 1 g or 2 g of C19-IG20%, or an equivalent volume of saline as placebo. The primary endpoint was the proportion of participants who remained asymptomatic through day 14 after infusion. Secondary endpoints included the proportion of individuals who required oxygen supplementation, any medically attended visit, hospitalisation, or ICU, and viral load reduction and viral clearance in nasopharyngeal swabs. Safety was assessed as the proportion of patients with adverse events. The trial was terminated early due to a lack of potential benefit in the target population in a planned interim analysis conducted in December 2021. ClinicalTrials.gov registry: NCT04847141. Findings: 461 individuals (mean age 39.6 years [SD 12.8]) were randomized and received the intervention within a mean of 3.1 (SD 1.27) days from a positive SARS-CoV-2 test. In the prespecified modified intention-to-treat analysis that included only participants who received a subcutaneous infusion, the primary outcome occurred in 59.9% (91/152) of participants receiving 1 g C19-IG20%, 64.7% (99/153) receiving 2 g, and 63.5% (99/156) receiving placebo (difference in proportions 1 g C19-IG20% vs. placebo, −3.6%; 95% CI -14.6% to 7.3%, p = 0.53; 2 g C19-IG20% vs placebo, 1.1%; −9.6% to 11.9%, p = 0.85). None of the secondary clinical efficacy endpoints or virological endpoints were significantly different between study groups. Adverse event rate was similar between groups, and no severe or life-threatening adverse events related to investigational product infusion were reported. Interpretation: Our findings suggested that administration of subcutaneous human hyperimmune immunoglobulin C19-IG20% to asymptomatic individuals with SARS-CoV-2 infection was safe but did not prevent development of symptomatic COVID-19. Funding: Grifols