RESUMO
Abstract When a SARS-CoV-2 RT-qPCR test is performed, it may determine an indirect measureof viral load called cycle threshold (Ct). Respiratory samples with Ct <25.0 cycles are consideredto contain a high viral load. We aimed to determine whether SARS-CoV-2 Ct at diagnosis couldpredict mortality in patients with hematologic malignancies (lymphomas, leukemias, multiplemyeloma) who contracted COVID-19. We included 35 adults with COVID-19 confirmed by RT-qPCR performed at diagnosis. We evaluated mortality due to COVID-19 rather than mortalitydue to the hematologic neoplasm or all-cause mortality. Twenty-seven (27) patients survivedand 8 died. The global mean Ct was 22.8 cycles with a median of 21.7. Among the survivors,the mean Ct was 24.2, and the median Ct value was 22.9 cycles. In the deceased patients, themean Ct was 18.0 and the median Ct value was 17.0 cycles. Using the Wilcoxon Rank Sum test,we found a significant difference (p = 0.035). SARS-CoV-2 Ct measured in nasal swabs obtainedat diagnosis from patients with hematologic malignancies may be used to predict mortality.
Resumen Cuando se realiza una RT-qPCR para SARS-CoV-2, es posible determinar una medidaindirecta de la carga viral llamada umbral de ciclado (Ct). Las muestras respiratorias con Ct<25,0 ciclos se consideran de alta carga viral. Nos propusimos determinar si el Ct para SARS-CoV-2 al diagnóstico predice la mortalidad en pacientes con neoplasias hematológicas (linfomas,leucemias, mielomas) que contrajeron COVID-19. Incluimos 35 adultos con COVID-19 confirmadopor RT-qPCR al diagnóstico. Evaluamos la mortalidad por COVID-19, no la mortalidad por la neo-plasia hematológica o la mortalidad por cualquier causa. De los 35 pacientes, 27 sobrevivierony 8 fallecieron. El Ct global medio fue 22,8 ciclos con una mediana de 21,7 ciclos. Entre lossobrevivientes, el Ct medio fue 24,2 ciclos con una mediana de 22,9 ciclos. Entre los fallecidos,el Ct medio fue 18,0 y el Ct mediano fue 17,0 ciclos. Empleando la prueba de suma de rangosde Wilcoxon, encontramos una diferencia significative (p = 0,035). En pacientes con neoplasiashematológicas infectados con coronavirus, el Ct de SARS-CoV-2 medido en hisopados nasales almomento del diagnóstico podría ser utilizado para predecir la mortalidad.
RESUMO
When a SARS-CoV-2 RT-qPCR test is performed, it may determine an indirect measure of viral load called cycle threshold (Ct). Respiratory samples with Ct <25.0 cycles are considered to contain a high viral load. We aimed to determine whether SARS-CoV-2 Ct at diagnosis could predict mortality in patients with hematologic malignancies (lymphomas, leukemias, multiple myeloma) who contracted COVID-19. We included 35 adults with COVID-19 confirmed by RT-qPCR performed at diagnosis. We evaluated mortality due to COVID-19 rather than mortality due to the hematologic neoplasm or all-cause mortality. Twenty-seven (27) patients survived and 8 died. The global mean Ct was 22.8 cycles with a median of 21.7. Among the survivors, the mean Ct was 24.2, and the median Ct value was 22.9 cycles. In the deceased patients, the mean Ct was 18.0 and the median Ct value was 17.0 cycles. Using the Wilcoxon Rank Sum test, we found a significant difference (p=0.035). SARS-CoV-2 Ct measured in nasal swabs obtained at diagnosis from patients with hematologic malignancies may be used to predict mortality.
