key: cord-0946586-plgmzyfj
authors: Cillóniz, Catia; Torres, Antoni; Garcia-Vidal, Carolina; Moreno-Garcia, Estela; Amaro, Rosanel; Soler, Nestor; Angeles Marcos, Mª; Rico, Verónica; Gabarrús, Albert; María Nicolás, José; Soriano, Alex
title: The value of C-reactive protein-to-lymphocyte ratio in predicting the severity of SARS-CoV-2 pneumonia
date: 2020-09-06
journal: Arch Bronconeumol
DOI: 10.1016/j.arbres.2020.07.038
sha: e39dc9d815205392a42ab86807cc84843996b7cc
doc_id: 946586
cord_uid: plgmzyfj

nan

J o u r n a l P r e -p r o o f 4

Clinical severity of COVID-19 infections ranges widely, from asymptomatic or mild disease of the upper airways to pneumonia and acute respiratory distress syndrome (ARDS) [1] [2] [3] . We aim to describe biological features and outcomes of 240 patients admitted for SARS-CoV-2 pneumonia, as well as identify predictors of intensive care unit (ICU) admission (either direct admission or transfer to ICU within 96 hours of admission from emergency department), need for invasive mechanical ventilation (IMV) and inhospital mortality.

For this retrospective, observational study, all consecutive patients with laboratoryconfirmed SARS-CoV-2 infection and pneumonia (positive result by real-time polymerase chain reaction testing of a oropharyngeal plus nasopharyngeal sample 4 ), who visited the emergency department and were subsequently admitted to the hospital between February 28 th and April 21 st , 2020, were included. Patients without pneumonia were excluded. The Institutional Ethics Board approved this study and due to its nature, waived the need for informed consent. Clinical outcomes were monitored until May 15 th , 2020. Patients were divided into two groups: non-ICU and ICU-admitted (either direct admission or transfer to ICU within 96 hours of admission from emergency department).

Descriptive statistics were used for basic features of study data; appropriate statistical tests were performed to compare both groups. Univariate and multivariable binary logistic regression 5 , multinomial logistic regression 5 and Cox regression 6 analyses were performed to identify variables associated with ICU admission, mechanical ventilation and in-hospital mortality, respectively. When compared to non-ICU patients, ICU-admitted patients were more likely to be men and have higher body mass index (BMI). ICU-admitted patients also showed higher levels of creatinine, C-reactive protein, neutrophils, lactate dehydrogenase (LDH), white blood cell count, troponin, D-dimer, ferritin, and troponin. Similarly, we observed elevated Creactive protein-to-lymphocyte, neutrophil-to-lymphocyte ratio and lower lymphocyte count and oxygen saturation upon admission (first 24h) in ICU-admitted patients. During hospitalization (days 3-5), those admitted to the ICU developed severe lymphopenia more frequently (0.6 vs. 1.1; P<0.001) than non-ICU patients. Levels of C-reactive protein, neutrophils, white blood cell count, alanine aminotransferase (ALT) and LDH, Ddimer and ferritin were higher in ICU-admitted patients over time (day 3-5) ( This cohort study provides the first description of COVID-19 pneumonia in Barcelona, Spain. Patients with higher BMI and elevated levels of C-reactive protein-to-lymphocyte ratio and ferritin upon admission presented with an increased risk of ICU admission. This immunological dysregulation in severe COVID-19 8 . Similarly, it is well known that obesity is a risk factor for severe infection, related to low-grade chronic inflammation and has a potential effect on immune responses 9 .

Interestingly, we observed that platelet levels were an additional variable independently associated with ICU admission in both patients who went directly to the ICU and those who transferred to the ICU within 96 hours of admission to the emergency department.

These results support the fact that a decrease in platelet count usually indicates multiple organ dysfunction, and provides prognostic information 10 .

Twenty-four percent of our patients underwent IMV. Notably, we found that C-reactive protein-to-lymphocyte ratio and ferritin levels upon admission were independently associated with the need for IMV. Previous studies reported that higher ferritin levels were associated with a clinical deterioration in patients with COVID-19. A meta-analysis also reported that both the neutrophil-to-lymphocyte ratio and C-reactive protein-tolymphocyte ratio significantly increased in severe COVID-19 cases 7 . However, this cohort study is the first of its nature to explore the value of the C-reactive protein-tolymphocyte ratio in patients with COVID-19 pneumonia. The level of C-reactive proteinto-lymphocyte ratio reflects the balance between the systemic inflammatory and immune responses. An elevated C-reactive protein-to-lymphocyte ratio indicates an increase in the systemic inflammatory response and a decrease in the immune response.

As we observed in our study, elevated C-reactive protein-to-lymphocyte ratio is an important predictor factor for both ICU admission (both direct admission and transfer to ICU) and need for IMV. The results of our study have important clinical implications and strengths. As C-reactive protein-to-lymphocyte ratio could be quickly calculated based on a routine blood test performed upon admission, clinicians may be able to identify high-risk patients with COVID-19 during the early stages of the infection. The main limitation of the study is that it includes patients from a single center. Notwithstanding, important preliminary results concerning risk factors for ICU admission and need for IMV in patients with COVID-19 pneumonia are provided.

Early recognition of easily obtainable markers upon hospital admission such as serum ferritin, D-dimer, platelet count and the C-reactive protein-to-lymphocyte ratio could help identify and prioritize patients with a higher probability for ICU admission (both direct admission and transfer to ICU) and need of IMV during the course of hospitalization.

Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus-Infected Pneumonia in Wuhan, China

Clinical course and outcomes of critically ill patients with SARS-CoV-2 pneumonia in Wuhan, China: a single-centered, retrospective, observational study

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Modelling Survival Data in Medical Research. second edition. chapman & hall/crc

Neutrophil-to-lymphocyte ratio and lymphocyte-to-Creactive protein ratio in patients with severe coronavirus disease 2019 (COVID-19): A meta-analysis

COVID-19: consider cytokine storm syndromes and immunosuppression

Obesity and the risk and outcome of infection

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