Pulmonary thrombosis associated with COVID-19 pneumonia: Beyond classical pulmonary thromboembolism.

BACKGROUND: Classical pulmonary thromboembolism (TE) and local pulmonary thrombosis (PT) have been suggested as mechanisms of thrombosis in COVID-19. However, robust evidence is still lacking because this was mainly based on retrospective studies, in which patients were included when TE was suspected. METHODS: All patients with COVID-19 pneumonia underwent computed tomography and pulmonary angiography in a prospective study. The main objective was to determine the number and percentage of thrombi surrounded by lung opacification (TSO) in each patient, as well as their relationship with percentage of lung involvement (TLI), to distinguish classical TE (with a random location of thrombi that should correspond to a percentage of TSO equivalent to the TLI) from PT. We determined TLI by artificial intelligence. Analyses at patient level (TLI and percentage of TSO) and at thrombi level (TLI and TSO) were performed. RESULTS: We diagnosed TE in 70 out of 184 patients. Three (2-8) thrombi/patient were detected. The percentage of TSO was 100% (75-100) per patient, and TLI was 19.9% (4.6-35.2). Sixty-five patients (92.9%) were above the random scenario with higher percentage of TSO than TLI. Most thrombi were TSO (n = 299, 75.1%). When evaluating by TLI (<10%, 10%-20%, 20%-30% and >30%), percentage of TSO was higher in most groups. Thrombi were mainly in subsegmental/segmental arteries, and percentage of TSO was higher in all locations. CONCLUSIONS: Thrombi in COVID-19 were found within lung opacities in a higher percentage than lung involvement, regardless of TLI and clot location, supporting the hypothesis of local PT rather than "classic TE".

Cardiopulmonary Complications after Pulmonary Embolism in COVID-19.

Although pulmonary embolism (PE) is a frequent complication in COVID-19, its consequences remain unknown. We performed pulmonary function tests, echocardiography and computed tomography pulmonary angiography and identified blood biomarkers in a cohort of consecutive hospitalized COVID-19 patients with pneumonia to describe and compare medium-term outcomes according to the presence of PE, as well as to explore their potential predictors. A total of 141 patients (56 with PE) were followed up during a median of 6 months. Post-COVID-19 radiological lung abnormalities (PCRLA) and impaired diffusing capacity for carbon monoxide (DLCOc) were found in 55.2% and 67.6% cases, respectively. A total of 7.3% had PE, and 6.7% presented an intermediate-high probability of pulmonary hypertension. No significant difference was found between PE and non-PE patients. Univariate analysis showed that age > 65, some clinical severity factors, surfactant protein-D, baseline C-reactive protein, and both peak red cell distribution width and Interleukin (IL)-10 were associated with DLCOc < 80%. A score for PCRLA prediction including age > 65, minimum lymphocyte count, and IL-1ß concentration on admission was constructed with excellent overall performance. In conclusion, reduced DLCOc and PCRLA were common in COVID-19 patients after hospital discharge, but PE did not increase the risk. A PCRLA predictive score was developed, which needs further validation.

Prevalence of pulmonary embolism in patients with COVID-19 pneumonia and high D-dimer values: A prospective study.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) pneumonia is associated to systemic hyper-inflammation and abnormal coagulation profile. D-dimer elevation is particularly frequent, and values higher than 1µg/mL have been associated with disease severity and in-hospital mortality. Previous retrospective studies found a high pulmonary embolism (PE) prevalence, however, it should be highlighted that diagnoses were only completed when PE was clinically suspected. MATERIAL AND METHODS: Single-center prospective cohort study. Between April 6th and April 17th 2020, consecutive confirmed cases of COVID-19 pneumonia with D-dimer >1 µg/mL underwent computed tomography pulmonary angiography (CTPA) to investigate the presence and magnitude of PE. Demographic and laboratory data, comorbidities, CTPA scores, administered treatments, and, clinical outcomes were analysed and compared between patients with and without PE. RESULTS: Thirty consecutive patients (11 women) were included. PE was diagnosed in 15 patients (50%). In patients with PE, emboli were located mainly in segmental arteries (86%) and bilaterally (60%). Patients with PE were significantly older (median age 67.0 (IQR 63.0-73.0) vs. 57.0 (IQR 48.0-69.0) years, p = .048) and did not differ in sex or risk factors for thromboembolic disease from the non-PE group. D-dimer, platelet count, and, C reactive protein values were significantly higher among PE patients. D-dimer values correlated with the radiologic magnitude of PE (p<0.001). CONCLUSIONS: Patients with COVID-19 pneumonia and D-dimer values higher than 1 µg/mL presented a high prevalence of PE, regardless of clinical suspicion. We consider that these findings could contribute to improve the prognosis of patients with COVID-19 pneumonia, by initiating anticoagulant therapy when a PE is found.

Electroforesis en Gel de Campo Pulsado (PFGE) para la diferenciación molecular de Listeria monocytogenes / Pulsed-field gel electrophoresis (PFGE) for the molecular differentiation of Listeria monocytogenes

En Colombia no es obligatoria la notificación deL. monocytogenes en alimentos, pero se vigilan los alimentos dealto riesgo. Clínicamente se reportan como microorganismoGram-positivo sólo cuando causan meningitis. L. monocytogeneses un patógeno intracelular, transmitido por alimentos, letalpara humanos y animales, que causa Listeriosis; enfermedadque genera varios brotes en el mundo, con pérdidashumanas y económicas. Pocos trabajos en Colombia hanlogrado identificar y serotipificar molecularmente losaislamientos, lo que sólo permite distribuir teóricamentelos serotipos en linajes. Esta revisión se limita a mostrarcaracterísticas del patógeno, su importancia en salud públicay en la industria de alimentos, generalidades de la PFGECHEF;identificando el protocolo estandarizado de trabajoy las enzimas de restricción adecuadas para cortar el ADN.Se encontró que la combinación de enzimas XbaI-AscI,seguida de ApaI es la que ofrece mejores resultados en ladiferenciación de los aislamientos; agrupándolos por linajes;mostrando variaciones intra-serotipo y que en varios paíseslatinoamericanos se analizan los resultados a través dePulseNet, lo que garantiza la comparación de los patronesde PFGE en igualdad de condiciones...

The reporting of L. monocytogenes in food in Colombia is not a mandatory; however, foods consideredhigh-risk are monitored, and the organism is only reported clinically as Gram-positive when it causesmeningitis. L. monocytogenes is a foodborne, intracellular, pathogen which causes listeriosis, a disease lethalto humans and animals. Outbreaks of this disease worldwide can bring about human and economiclosses. Only a few studies in Colombia have been able to identify and molecularly serotype isolatesallowing only the theoretical distribution of serotypes by lineage. This review explains the characteristicsof the pathogen, its importance in public health and in the food industry, and provides an overview ofPFGE-CHEF; identifying the standard work protocol and the appropriate restriction enzymes to cutDNA. We found that the enzyme combination, XbaI-AscI, followed by ApaI offers the best results todifferentiate isolates, by grouping them by lineages, and displaying intra-serotype variations. Additionally,we found that in several Latin American countries the results are analyzed using PulseNet; this ensuresthe comparison of PFGE patterns in equivalent conditions...

Na Colômbia não há uma notificação compulsóriade L. monocytogenes em alimentos, mas alimentos de altorisco são monitorados. Clinicamente, são relatados comoorganismos Gram-positivos apenas quando eles causammeningite. L. monocytogenes é um patógeno intracelularde origem alimentar, letal para seres humanos e animais,que causa a listeriose, que gera surtos em todo o mundo,com perdas humanas e econômicas. Poucos trabalhos naColômbia identificaram e sorotipificaram molecularmenteos isolados, que só permite a distribuição de sorotiposteoricamente em linhagens. Esta avaliação é limitada amostrar características do patógeno, sua importância nasaúde pública e na indústria de alimentos, e uma visãogeral do PFGE-CHEF; identificar o protocolo-padrão detrabalho e enzimas de restrição apropriadas para cortar oADN. Verificou-se que a combinação de enzimas XbaIAscI,seguido por ApaI representa a combinação de enzimasque ofereceu melhores resultados na diferenciação dosisolados, agrupando-a por linhagens, mostrando a variaçãointra-serotipo e que, em muitos países da América Latina,os resultados são analisados através PulseNet, que asseguraa comparação de padrões de PFGE em igualdade decondições...