Gestión de calidad en equipos de gases en sangre POCT. Expandiendo las fronteras del laboratorio / Quality management in POCT blood gas equipment. Expanding the frontiers of the laboratory

La realización de pruebas de laboratorio en el lugar de atención del paciente (POCT) de equipos de gases en sangre representa un desafío continuo tanto para los usuarios como para el laboratorio. La vulnerabilidad al error y la amenaza del riesgo que rodea esta forma de trabajo obliga a establecer un sistema de trabajo robusto para la obtención de un "resultado confiable" cerca del paciente crítico. La formación de un grupo interdisciplinario, la capacitación de usuarios externos al laboratorio, el aseguramiento de la calidad analítica y la conectividad, son los cuatro pilares sobre los cuales se sostiene el éxito de esta nueva era de laboratorio clínico. Además es necesaria la reinvención de la imagen bioquímica, asumiendo un rol de líder, comunicador, asesor e integrado al sistema de salud (AU)

Point of care laboratory testing (POCT) with blood gas equipment is an ongoing challenge for both the users and the laboratory. The vulnerability to error and the threat of risk that surrounds this way of working necessitates the establishment of a robust working system to obtain "reliable results" for the critically ill patient. The creation of an interdisciplinary group, the training of external users, analytical quality assurance, and connectivity are the four pillars on which the success of this new era of clinical laboratories is based. It is also necessary to reinvent the biochemical image, assuming the role of leader, communicator, and advisor integrated into the health system (AU)

Development of a Rapid Gold Nanoparticle-Based Lateral Flow Immunoassay for the Detection of Dengue Virus.

Flavivirus detection in humans and mosquito reservoirs has been an important issue since it can cause a variety of illnesses and could represent a health problem in geographical zones where the vector is endemic. In this work, we designed and characterized a biosensor based on gold nanoparticles (AuNPs) and antibody 4G2 for the detection of dengue virus (DENV) in vitro, obtaining different conjugates (with different antibody concentrations). The AuNP-4G2 conjugates at concentrations of 1, 3, and 6 µg/mL presented an increase in the average hydrodynamic diameter compared to the naked AuNPs. Also, as part of the characterization, differences in the UV-Vis absorbance spectrum and electrophoretic migration were observed between the conjugated AuNPs (with BSA or antibody) and naked AuNPs. Additionally, we used this biosensor (AuNP-4G2 conjugate with 3 µg/mL antibody) in the assembly of a competitive lateral flow assay (LFA) for the development of an alternative test to detect the flavivirus envelope protein in isolated DENV samples as a future tool for dengue detection (and other flaviviruses) in the mosquito vector (Aedesaegypti) for the identification of epidemic risk regions. Functionality tests were performed using Dengue virus 2 isolated solution (TCID50/mL = 4.58 × 103) as a positive sample and PBS buffer as a negative control. The results showed that it is possible to detect Dengue virus in vitro with this gold nanoparticle-based lateral flow assay with an estimated detection limit of 5.12 × 102 PFU. We suggest that this biosensor could be used as an additional detection tool by coupling it to different point-of-care tests (POCT) for the easy detection of other flaviviruses.

Papel de las pruebas rápidas (POCT) en el diagnóstico del SARS-COV-2, agente causal de COVID-19 / Role of Rapid Tests (POCT) in the Diagnosis of SARS-VOC-2, Causal Agent of COVID-19

Resumen El estándar de oro actual para la detección de SARS-CoV-2, agente causal de la pandemia de neumonía atípica (COVID-19) que apareció por primera vez en la ciudad de Wuhan (provincia de Hubei, China) en diciembre de 2019 (1), es la RT-qPCR. El protocolo estándar implica la transcripción inversa de ARN de SARS-CoV-2 en cadenas de ADN complementarias (ADNc), seguida de la amplificación de regiones específicas del ADNc. Este procedimiento demanda varias horas para ser completado y deriva en que la información final del estado de la infección pueda demorar hasta 24 horas. Ante la necesidad de disminuir el riesgo de una posible propagación viral dentro de la población originada por la rápida transmisión del SARS-CoV-2, se ha buscado prevenir el contagio, la propagación nosocomial y la transmisión comunitaria posterior, a través de la identificación rápida de casos sospechosos, y predecir las posteriores ondas infecciosas de recurrencia viral. Para esto, se vienen desarrollando métodos de laboratorio rápidos o point of care testing (POCT), que disminuyen el tiempo de diagnóstico y minimizan el riesgo de contagio por parte de los operadores.

Abstract The gold test to detect SARS-CoV-2, the etiologic agent that leads to the pandemic of atypical pneumonia (COVID 2019) that first appeared in Wuhan City, Hubei Province of China in December 2019 (1), is the RT-qPCR. The standard protocol involves reverse transcription of SARS-CoV-2 RNA into complementary DNA strands (cDNA), followed by the amplification of cDNA specific regions, a procedure that takes several hours to complete and which results in the final information from the infection status can take up to 24 hours. For this reason, and due to the need to reduce the risk of possible viral spread within the population caused by the fast transmission of SARS-CoV-2, in order to prevent nosocomial spread and subsequent community transmission through the quick identification of suspected cases, and to predict the further infectious waves of viral recurrence, rapid laboratory methods or Point of Care Testing (POCT) are being developed to reduce the diagnosis time and minimize the risk of contagion by the operators. These tests are discussed below.

Developments in Transduction, Connectivity and AI/Machine Learning for Point-of-Care Testing.

We review some emerging trends in transduction, connectivity and data analytics for Point-of-Care Testing (POCT) of infectious and non-communicable diseases. The patient need for POCT is described along with developments in portable diagnostics, specifically in respect of Lab-on-chip and microfluidic systems. We describe some novel electrochemical and photonic systems and the use of mobile phones in terms of hardware components and device connectivity for POCT. Developments in data analytics that are applicable for POCT are described with an overview of data structures and recent AI/Machine learning trends. The most important methodologies of machine learning, including deep learning methods, are summarised. The potential value of trends within POCT systems for clinical diagnostics within Lower Middle Income Countries (LMICs) and the Least Developed Countries (LDCs) are highlighted.