Validation of the PESI Scale to Predict in-Hospital Mortality in Patients with Pulmonary Thromboembolism Secondary to SARS CoV - 2 Infection.

OBJECTIVE: To evaluate the discriminative ability and the calibration of the Pulmonary Embolism Severity Index (PESI) to predict in-hospital mortality in patients with Pulmonary Embolism (PE) secondary to COVID 19 in two hospitals in Bogotá. METHODS: External validation study of a prediction model based on a retrospective cohort of patients with PE secondary to COVID-19 treated at Hospital Universitario San Ignacio and Hospital universitario La Samaritana, between March 2020 and August 2021. Calibration of the scale was evaluated using the Hosmer-Lemeshow test and a calibration belt diagram. Discrimination ability was evaluated using a ROC curve. RESULTS: 272 patients were included (median age 61.5 years, male 58.8%). PE was diagnosed in 45.6% of the patients at the time of admission. Of the remaining 54.4%, 95.9% received thromboprophylaxis until the time of diagnosis.17.6% of the patients died. Regarding calibration, the scale systematically underestimates risk in all classes of PESI. For class I, the ratio of observed/expected events was 4.4 vs 0.8%, class II 4.8 vs 1.8%, class III 15.2 vs 4.2%, class IV 14.3 vs 5.9% and class V 46.7 vs 5.8%. The calibration test rejected the adequate calibration hypothesis (p < 0.001). The discriminatory ability was adequate (AUC = 0.7128, 95% CI 0.63-0.79). CONCLUSIONS: The PESI scale in patients with PE secondary to COVID 19 underestimates the risk of in-hospital mortality, while maintaining adequate discrimination. It is suggested not to use the PESI scale until it is recalibrated in this context.

Real-time PCR assay for the diagnosis of pleural tuberculosis.

INTRODUCTION: The diagnosis of pleural tuberculosis requires an invasive and time-consuming reference method. Polymerase chain reaction (PCR) is rapid, but validation in pleural tuberculosis is still weak. OBJECTIVE: To establish the operating characteristics of real-time polymerase chain reaction (RT-PCR) hybridization probes for the diagnosis of pleural tuberculosis. METHODS: The validity of the RT-PCR hybridization probes was evaluated compared to a composite reference method by a cross-sectional study at the Hospital Universitario de la Samaritana. 40 adults with lymphocytic pleural effusion were included. Pleural tuberculosis was confirmed (in 9 patients) if the patient had at least one of three tests using the positive reference method: Ziehl-Neelsen or Mycobacterium tuberculosis culture in fluid or pleural tissue, or pleural biopsy with granulomas. Pleural tuberculosis was ruled out (in 31 patients) if all three tests were negative. The operating characteristics of the RT-PCR, using the Mid-P Exact Test, were determined using the OpenEpi 2.3 Software (2009). RESULTS: The RT-PCR hybridization probes showed a sensitivity of 66.7% (95% CI: 33.2%-90.7%) and a specificity of 93.5% (95% CI: 80.3%-98.9%). The PPV was 75.0% (95% CI: 38.8%-95.6%) and a NPV of 90.6% (95% CI: 76.6%-97.6%). Two false positives were found for the test, one with pleural mesothelioma and the other with chronic pleuritis with mesothelial hyperplasia. CONCLUSIONS: The RT-PCR hybridization probes had good specificity and acceptable sensitivity, but a negative value cannot rule out pleural tuberculosis.

INTRODUCCIÓN: El diagnóstico de tuberculosis pleural requiere un método de referencia invasivo y demorado. La reacción en cadena de la polimerasa es rápida, pero su validación en tuberculosis pleural aún es débil. OBJETIVO: Establecer las características operativas de la reacción en cadena de la polimerasa en tiempo real (RT-PCR) sondas de hibridación para el diagnóstico de tuberculosis pleural. MÉTODOS: Se evaluó la validez de la RT-PCR sondas de hibridación comparada con un método de referencia compuesto mediante un estudio transversal en el Hospital Universitario de la Samaritana. Se incluyeron 40 adultos con derrame pleural linfocitario. Tuberculosis pleural fue confirmada (en 9 pacientes) si el paciente tenía mínimo una de tres pruebas del método de referencia positiva: Ziehl-Neelsen o cultivo para Mycobacterium tuberculosis en líquido o tejido pleural, o biopsia pleural con granulomas; se descartó tuberculosis pleural (en 31 pacientes) si las tres pruebas eran negativas. Se determinaron las características operativas de la RT-PCR, mediante la Prueba Mid-P Exact, con el Software OpenEpi 2.3 (2009). RESULTADOS: La RT-PCR sondas de hibridación mostró una sensibilidad del 66.7% (IC 95%: 33.2%-90.7%) y una especificidad del 93.5% (IC 95%: 80.3%-98.9%). El VPP fue de 75.0% (IC 95%: 38.8%-95.6%) y un VPN de 90.6% (IC 95%: 76.6%-97.6%). Se encontraron dos falsos positivos para la prueba, uno con mesotelioma pleural y otro con pleuritis crónica con hiperplasia mesotelial. CONCLUSIONES: La RT-PCR sondas de hibridación tuvo una buena especificidad y una aceptable sensibilidad, pero un valor negativo no puede descartar tuberculosis pleural.

Real-time PCR assay for the diagnosis of pleural tuberculosis / Reacción en cadena de la polimerasa en tiempo real para el diagnóstico de tuberculosis pleural

Abstract Introduction: The diagnosis of pleural tuberculosis requires an invasive and time-consuming reference method. Polymerase chain reaction (PCR) is rapid, but validation in pleural tuberculosis is still weak. Objective: To establish the operating characteristics of real-time polymerase chain reaction (RT-PCR) hybridization probes for the diagnosis of pleural tuberculosis. Methods: The validity of the RT-PCR hybridization probes was evaluated compared to a composite reference method by a cross-sectional study at the Hospital Universitario de la Samaritana. 40 adults with lymphocytic pleural effusion were included. Pleural tuberculosis was confirmed (in 9 patients) if the patient had at least one of three tests using the positive reference method: Ziehl-Neelsen or Mycobacterium tuberculosis culture in fluid or pleural tissue, or pleural biopsy with granulomas. Pleural tuberculosis was ruled out (in 31 patients) if all three tests were negative. The operating characteristics of the RT-PCR, using the Mid-P Exact Test, were determined using the OpenEpi 2.3 Software (2009). Results: The RT-PCR hybridization probes showed a sensitivity of 66.7% (95% CI: 33.2%-90.7%) and a specificity of 93.5% (95% CI: 80.3%-98.9%). The PPV was 75.0% (95% CI: 38.8%-95.6%) and a NPV of 90.6% (95% CI: 76.6%-97.6%). Two false positives were found for the test, one with pleural mesothelioma and the other with chronic pleuritis with mesothelial hyperplasia. Conclusions: The RT-PCR hybridization probes had good specificity and acceptable sensitivity, but a negative value cannot rule out pleural tuberculosis.

Resumen Introducción: El diagnóstico de tuberculosis pleural requiere un método de referencia invasivo y demorado. La reacción en cadena de la polimerasa es rápida, pero su validación en tuberculosis pleural aún es débil. Objetivo: Establecer las características operativas de la reacción en cadena de la polimerasa en tiempo real (RT-PCR) sondas de hibridación para el diagnóstico de tuberculosis pleural. Métodos: Se evaluó la validez de la RT-PCR sondas de hibridación comparada con un método de referencia compuesto mediante un estudio transversal en el Hospital Universitario de la Samaritana. Se incluyeron 40 adultos con derrame pleural linfocitario. Tuberculosis pleural fue confirmada (en 9 pacientes) si el paciente tenía mínimo una de tres pruebas del método de referencia positiva: Ziehl-Neelsen o cultivo para Mycobacterium tuberculosis en líquido o tejido pleural, o biopsia pleural con granulomas; se descartó tuberculosis pleural (en 31 pacientes) si las tres pruebas eran negativas. Se determinaron las características operativas de la RT-PCR, mediante la Prueba Mid-P Exact, con el Software OpenEpi 2.3 (2009). Resultados: La RT-PCR sondas de hibridación mostró una sensibilidad del 66.7% (IC 95%: 33.2%-90.7%) y una especificidad del 93.5% (IC 95%: 80.3%-98.9%). El VPP fue de 75.0% (IC 95%: 38.8%-95.6%) y un VPN de 90.6% (IC 95%: 76.6%-97.6%). Se encontraron dos falsos positivos para la prueba, uno con mesotelioma pleural y otro con pleuritis crónica con hiperplasia mesotelial. Conclusiones: La RT-PCR sondas de hibridación tuvo una buena especificidad y una aceptable sensibilidad, pero un valor negativo no puede descartar tuberculosis pleural.