Transient Changes in the Plasma of Astrocytic and Neuronal Injury Biomarkers in COVID-19 Patients without Neurological Syndromes.

The levels of several glial and neuronal plasma biomarkers have been found to increase during the acute phase in COVID-19 patients with neurological symptoms. However, replications in patients with minor or non-neurological symptoms are needed to understand their potential as indicators of CNS injury or vulnerability. Plasma levels of glial fibrillary acidic protein (GFAP), neurofilament light chain protein (NfL), and total Tau (T-tau) were determined by Single molecule array (Simoa) immunoassays in 45 samples from COVID-19 patients in the acute phase of infection [moderate (n = 35), or severe (n = 10)] with minor or non-neurological symptoms; in 26 samples from fully recovered patients after ~2 months of clinical follow-up [moderate (n = 23), or severe (n = 3)]; and in 14 non-infected controls. Plasma levels of the SARS-CoV-2 receptor, angiotensin-converting enzyme 2 (ACE2), were also determined by Western blot. Patients with COVID-19 without substantial neurological symptoms had significantly higher plasma concentrations of GFAP, a marker of astrocytic activation/injury, and of NfL and T-tau, markers of axonal damage and neuronal degeneration, compared with controls. All these biomarkers were correlated in COVID-19 patients at the acute phase. Plasma GFAP, NfL and T-tau levels were all normalized after recovery. Recovery was also observed in the return to normal values of the quotient between the ACE2 fragment and circulating full-length species, following the change noticed in the acute phase of infection. None of these biomarkers displayed differences in plasma samples at the acute phase or recovery when the COVID-19 subjects were sub-grouped according to occurrence of minor symptoms at re-evaluation 3 months after the acute episode (so called post-COVID or "long COVID"), such as asthenia, myalgia/arthralgia, anosmia/ageusia, vision impairment, headache or memory loss. Our study demonstrated altered plasma GFAP, NfL and T-tau levels in COVID-19 patients without substantial neurological manifestation at the acute phase of the disease, providing a suitable indication of CNS vulnerability; but these biomarkers fail to predict the occurrence of delayed minor neurological symptoms.

[Application of validated severity scores for pneumonia caused by SARS-CoV-2]. / Aplicación de escalas pronósticas de gravedad en la neumonía por SARS-CoV-2.

OBJECTIVES: Compare the accuracy of PSI, CURB-65, MuLBSTA and COVID-GRAM prognostic scores to predict mortality, the need for invasive mechanical ventilation in patients with pneumonia caused by SARS-CoV-2 and assess the coexistence of bacterial respiratory tract infection during admission. METHODS: Retrospective observational study that included hospitalized adults with pneumonia caused by SARS-CoV-2 from 15/03 to 15/05/2020. We excluded immunocompromised patients, nursing home residents and those admitted in the previous 14 days for another reasons. Analysis of ROC curves was performed, calculating the area under the curve for the different scales, as well as sensitivity, specificity and predictive values. RESULTS: A total of 208 patients were enrolled, aged 63±17 years, 57,7% were men; 38 patients were admitted to ICU (23,5%), of these patients 33 required invasive mechanical ventilation (86,8%), with an overall mortality of 12,5%. Area under the ROC curves for mortality of the scores were: PSI 0,82 (95% CI: 0,73-0,91), CURB-65 0,82 (0,73-0,91), MuLBSTA 0,72 (0,62-0,81) and COVID-GRAM 0,86 (0,70-1). Area under the curve for needing invasive mechanical ventilation was: PSI 0,73 (95% CI: 0,64-0,82), CURB-65 0,66 (0,55-0,77), MuLBSTA 0,78 (0,69-0,86) and COVID-GRAM 0,76 (0,67-0,85), respectively. Patients with bacterial co-infections of the respiratory tract were 20 (9,6%), the most frequent strains being Pseudomonas aeruginosa and Klebsiella pneumoniae. CONCLUSIONS: In our study, the COVID-GRAM score was the most accurate to identify patients with higher mortality with pneumonia caused by SARS-CoV-2; however, none of these scores accurately predicts the need for invasive mechanical ventilation with ICU admission. The 10% of patients admitted presented bacterial respiratory co-infection.

Clinical Frailty Score vs Hospital Frailty Risk Score for predicting mortality and other adverse outcome in hospitalised patients with COVID-19: Spanish case series.

OBJECTIVES: Frailty can be used as a predictor of adverse outcomes in people with coronavirus disease 2019 (COVID-19). The aim of the study was to analyse the prognostic value of two different frailty scores in patients hospitalised for COVID-19. MATERIAL AND METHODS: This retrospective cohort study included adult (≥18 years) inpatients with COVID-19 and took place from 3 March to 2 May 2020. Patients were categorised by Clinical Frailty Score (CFS) and Hospital Frailty Risk Score (HFRS). The primary outcome was in-hospital mortality, and secondary outcomes were tocilizumab treatment, length of hospital stay, admission in intensive care unit (ICU) and need for invasive mechanical ventilation. Results were analysed by multivariable logistic regression and expressed as odds ratios (ORs), adjusting for age, sex, kidney function and comorbidity. RESULTS: Of the 290 included patients, 54 were frail according to the CFS (≥5 points; prevalence 18.6%, 95% confidence interval [CI]: 14.4-23.7) vs 65 by HFRS (≥5 points; prevalence: 22.4%, 95% CI 17.8-27.7). Prevalence of frailty increased with age according to both measures: 50-64 years, CFS 1.9% vs HFRS 12.3%; 65-79 years, CFS 31.5% vs HFRS 40.0%; and ≥80 years, CFS 66.7% vs HFRS 40.0% (P < .001). CFS-defined frailty was independently associated with risk of death (OR 3.67, 95% CI 1.49-9.04) and less treatment with tocilizumab (OR 0.28, 95% CI 0.08-0.93). HFRS-defined frailty was independently associated with length of hospital stay over 10 days (OR 2.89, 95% CI 1.53-5.44), ICU admission (OR 4.18, 95% CI 1.84-9.52) and invasive mechanical ventilation (OR 5.93, 95% CI 2.33-15.10). CONCLUSION: In the spring 2020 wave of the COVID-19 pandemic in Spain, CFS-defined frailty was an independent predictor for death, while frailty as measured by the HFRS was associated with length of hospital stay over 10 days, ICU admission and use of invasive mechanical ventilation.

Application of validated severity scores for pneumonia caused by SARS-CoV-2.

OBJECTIVES: Compare the accuracy of PSI, CURB-65, MuLBSTA and COVID-GRAM prognostic scores to predict mortality, the need for invasive mechanical ventilation (IMV) in patients with pneumonia caused by SARS-CoV-2 and assess the coexistence of bacterial respiratory tract infection during admission. METHODS: Retrospective observational study that included hospitalized adults with pneumonia caused by SARS-CoV-2 from 15/03 to 15/05/2020. We excluded immunocompromised patients, nursing home residents and those admitted in the previous 14 days for another reasons. Analysis of ROC curves was performed, calculating the area under the curve for the different scales, as well as sensitivity, specificity and predictive values. RESULTS: 208 patients were enrolled, aged 63 ± 17 years, 577% were men. 38 patients were admitted to ICU (235%), of these patients 33 required IMV (868%), with an overall mortality of 125%. Area under the ROC curves for mortality of the scores were: PSI 082 (95% CI 073-091), CURB-65 082 (073-091), MuLBSTA 072 (062-081) and COVID-GRAM 086 (070-1). Area under the curve for needing IMV was: PSI 073 (95% CI 064-082), CURB-65 066 (055-077), MuLBSTA 078 (069-086) and COVID-GRAM 076 (067-085), respectively. Patients with bacterial co-infections of the respiratory tract were 20 (9,6%), the most frequent strains being Pseudomonas aeruginosa and Klebsiella pneumoniae. CONCLUSIONS: In our study, the COVID-GRAM score was the most accurate to identify patients with higher mortality with pneumonia caused by SARS-CoV-2; however, none of these scores accurately predicts the need for IMV with ICU admission. 10% of patients admitted presented bacterial respiratory co-infection.

OBJETIVOS: Comparar el rendimiento de las escalas pronósticas PSI, CURB-65, MuLBSTA y COVID-GRAM para predecir mortalidad y necesidad de ventilación mecánica invasiva (VMI) en pacientes con neumonía por SARS-CoV-2. Valorar la existencia de coinfección bacteriana respiratoria durante el ingreso. MÉTODO: Estudio observacional retrospectivo que incluyó adultos hospitalizados con neumonía por SARS-CoV-2 del 15/03 al 15/05/2020. Se excluyeron aquellos inmunodeprimidos, institucionalizados e ingresados en los 14 días previos por otro motivo. Se realizó un análisis de curvas ROC, calculando el área bajo la curva para las diferentes escalas, así como sensibilidad, especificidad y valores predictivos. RESULTADOS: Se incluyeron 208 pacientes, con edad de 63 ± 17 años; el 57,7% eran hombres. Ingresaron en UCI 38 (23,5%), precisando de estos VMI 33 (86,8%), con una mortalidad global del 12,5%. Las áreas bajo las curvas ROC para mortalidad de los scores fueron: PSI 0,82 (95% IC 0,73­0,91), CURB-65 0,82 (0,73­0,91), MuLBSTA 0,72 (0,62­0,81) y COVID-GRAM 0,86 (0,70­1). Las áreas para necesidad de VMI fueron: PSI 0,73 (95% IC 0,64­0,82), CURB-65 0,66 (0,55­0,77), MuLBSTA 0,78 (0,69­0,86) y COVID-GRAM 0,76 (0,67­0,85), respectivamente. Los pacientes que presentaron coinfección bacteriana respiratoria fueron 20 (9.6%) siendo los gérmenes más frecuentes Pseudomonas aeruginosa y Klebsiella pneumoniae. CONCLUSIONES: En nuestro estudio el score COVID-GRAM fue el más preciso para identificar los pacientes con mayor mortalidad ingresados con neumonía por SARS-CoV-2, no obstante, ninguno de estos scores predice de forma precisa la necesidad de VMI con ingreso en UCI. El 10% de los pacientes presentó coinfección bacteriana respiratoria.

Plasma ACE2 species are differentially altered in COVID-19 patients.

Studies are needed to identify useful biomarkers to assess the severity and prognosis of COVID-19 disease, caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2) virus. Here, we examine the levels of various plasma species of the SARS-CoV-2 host receptor, the angiotensin-converting enzyme 2 (ACE2), in patients at different phases of the infection. Human plasma ACE2 species were characterized by immunoprecipitation and western blotting employing antibodies against the ectodomain and the C-terminal domain, using a recombinant human ACE2 protein as control. In addition, changes in the cleaved and full-length ACE2 species were also examined in serum samples derived from humanized K18-hACE2 mice challenged with a lethal dose of SARS-CoV-2. ACE2 immunoreactivity was present in human plasma as several molecular mass species that probably comprise truncated (70 and 75 kDa) and full-length forms (95, 100, 130, and 170 kDa). COVID-19 patients in the acute phase of infection (n = 46) had significantly decreased levels of ACE2 full-length species, while a truncated 70-kDa form was marginally higher compared with non-disease controls (n = 26). Levels of ACE2 full-length species were in the normal range in patients after a recovery period with an interval of 58-70 days (n = 29), while the 70-kDa species decreased. Levels of the truncated ACE2 species served to discriminate between individuals infected by SARS-CoV-2 and those infected with influenza A virus (n = 17). In conclusion, specific plasma ACE2 species are altered in patients with COVID-19 and these changes normalize during the recovery phase. Alterations in ACE2 species following SARS-CoV-2 infection warrant further investigation regarding their potential usefulness as biomarkers for the disease process and to asses efficacy during vaccination.

Male pituitary-gonadal axis dysfunction in post-acute COVID-19 syndrome-Prevalence and associated factors: A Mediterranean case series.

OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 through angiotensin-converting enzyme 2 receptor can harm testes function. The objectives were to analyse the prevalence of low serum testosterone (LT) and impaired fertility potential (Leydig and Sertoli cells dysfunction, respectively) in coronavirus disease 2019 (COVID-19) male survivors and to evaluate acute infection-related associated factors. Also, we explore its association with post-acute COVID-19 syndrome (PCS) and quality of life (QOL). MATERIALS AND METHODS: Male adults recovered from polymerase chain reaction-confirmed COVID-19 were offered a structured evaluation 8-12 weeks after recovery. The main outcome measure(s) were as follows: LT, defined as total testosterone (TT) < 2 ng/ml or if TT levels 2-4 ng/ml as calculated free testosterone < 6.36 ng/dl; Sertoli cell dysfunction was defined as inhibin-B < 89 pg/ml. Secondary outcome-associated factors were analysed by multiple logistic regression (odds ratio; 95% confidence interval [CI]). QOL was evaluated by SF-36 v.2. RESULTS: One hundred and forty-three patients were evaluated at a median (interquartile range) of 77 days (72-83) after disease onset; 72% of them recovered from severe pneumonia. LT was detected in 41 patients (28.7%; 95% CI: 21.8-36.5). Low levels of inhibin-B were detected in 25 patients (18.1%; 95% CI: 12.5-25.3). After multivariate adjustment, obesity and hypokalaemia were associated with LT, whereas age more than 65 was an independent predictor of Sertoli cell dysfunction. LT or Sertoli cell dysfunction was not associated with PCS. Patients with LT had a lower score in four domains of QOL. CONCLUSIONS: Prevalence of male LT and impaired fertility potential in COVID-19 survivors is high in the medium term. Traditional risk factors and severity markers for COVID-19 could be predictive.

Medium-term serostatus in Spanish case series recovered from SARS-CoV-2 infection.

The medium-term serologic response of SARS-CoV-2 infection recovered individuals is not well known. The aims were to quantify the incidence of seropositive failure in the medium term in a cohort of patients with different COVID-19 severity and to analyze its associated factors. Patients who had recovered from mild and severe forms of SARS-CoV-2 infection in an Academic Spanish hospital (March 12-May 2, 2020), were tested for total anti-SARS-CoV-2 antibodies by electrochemiluminescence immunoassay (Elecsys Anti-SARS-CoV-2 test; Roche Diagnostics GmbH). The non-seropositive status (seropositive failure) incidence (95% CI) was determined. Associations were tested by multiple logistic regression in a global cohort and severe pneumonia subpopulation. Of 435 patients with PCR-confirmed SARS-CoV-2, a serological test was carried out in 325: 210 (64.6%) had severe pneumonia (hospitalized patients), 51 (15.7%) non-severe pneumonia (managed as outpatients), and 64 (19.7%) mild cases without pneumonia. After a median (IQR) of 76 days (70-83) from symptom onset, antibody responses may not consistently develop or reach levels sufficient to be detectable by antibody tests (non-seropositive incidence) in 6.9% (95% CI, 4.4-10.6) and 20.3% (95% CI, 12.2-31.7) of patients with and without pneumonia, respectively. Baseline independent predictors of seropositive failure were higher leukocytes and fewer days of symptoms before admission, while low glomerular filtrate and fever seem associated with serologic response. Age, comorbidity or immunosuppressive therapies (corticosteroids, tocilizumab) did not influence antibody response. In the medium-term, SARS-CoV-2 seropositive failure is not infrequent in COVID-19 recovered patients. Age, comorbidity or immunosuppressive therapies did not influence antibody response.

Fatality and risk features for prognosis in COVID-19 according to the care approach - a retrospective cohort study.

INTRODUCTION: This study analyzed the impact of a categorized approach, based on patients' prognosis, on major outcomes and explanators in patients hospitalized for COVID-19 pneumonia in an academic center in Spain. METHODS: Retrospective cohort study (March 3 to May 2, 2020). Patients were categorized according to the followed clinical management, as maximum care or limited therapeutic effort (LTE). Main outcomes were all-cause mortality and need for invasive mechanical ventilation (IMV). Baseline factors associated with outcomes were analyzed by multiple logistic regression, estimating odds ratios (OR; 95%CI). RESULTS: Thirty-hundred and six patients were hospitalized, median age 65.0 years, 57.8% males, 53.3% Charlson index ≥3. The overall all-cause fatality rate was 15.0% (n = 46). Maximum care was provided in 238 (77.8%), IMV was used in 38 patients (16.0%), and 5.5% died. LTE was decided in 68 patients (22.2%), none received IMV and fatality was 48.5%. Independent risk factors of mortality under maximum care were lymphocytes <790/mm3, troponin T >15ng/L and hypotension. Advanced age, lymphocytes <790/mm3 and BNP >240pg/mL independently associated with IMV requirement. CONCLUSION: Overall fatality in the cohort was 15% but markedly varied regarding the decided approach (maximum care versus LTE), translating into nine-fold higher mortality and different risk factors.

An integrated emergency department/hospital at home model in mild COVID-19 pneumonia: feasibility and outcomes after discharge from the emergency department.

To evaluate the effectiveness of an integrated emergency department (ED)/hospital at home (HH) medical care model in mild COVID-19 pneumonia and evaluate baseline predictors of major outcomes and potential savings. Retrospective cohort study with patients evaluated for COVID-19 pneumonia in the ED, from March 3 to April 30, 2020. All of them were discharged home and controlled by HH. The main outcomes were ED revisit and the need for deferred hospital admission (protocol failure). Outcome predictors were analyzed by simple logistic regression model (OR; 95% CI). Potential savings of this medical care model were estimated. Of the 377 patients attended in the ED, 109 were identified as having mild pneumonia and were included in the ED/HH medical care model. Median age was 50.0 years, 52.3% were males and 57.8% had Charlson index ≥ 1. The median HH stay was 8 (IQR 3.7-11) days. COVID-19-related ED revisit was 19.2% (n = 21) within 6 days (IQR 3-12.5) after discharge from ED. Overall protocol failure (deferred hospital admission) was 6.4% (n = 7), without ICU admission. The ED/HH model provided potential cost savings of 77% compared to traditional stay, due to the costs of home care entails 23% of the expenses generated by a conventional hospital stay. 789 days of hospital stay were avoided by HH, rather than hospital admission. An innovative ED/HH model for selected patients with mild COVID-19 pneumonia is feasible, safe and effective. Less than 6.5% of patients requiring deferred hospital admission and potential savings were generated due to hospitalization.

Post-acute COVID-19 syndrome. Incidence and risk factors: A Mediterranean cohort study.

OBJECTIVES: This study aims to analyze the incidence of Post-acute COVID-19 syndrome (PCS) and its components, and to evaluate the acute infection phase associated risk factors. METHODS: A prospective cohort study of adult patients who had recovered from COVID-19 (27th February to 29th April 2020) confirmed by PCR or subsequent seroconversion, with a systematic assessment 10-14 weeks after disease onset. PCS was defined as the persistence of at least one clinically relevant symptom, or abnormalities in spirometry or chest radiology. Outcome predictors were analyzed by multiple logistic regression (OR; 95%CI). RESULTS: Two hundred seventy seven patients recovered from mild (34.3%) or severe (65.7%) forms of SARS-CoV-2 infection were evaluated 77 days (IQR 72-85) after disease onset. PCS was detected in 141 patients (50.9%; 95%CI 45.0-56.7%). Symptoms were mostly mild. Alterations in spirometry were noted in 25/269 (9.3%), while in radiographs in 51/277 (18.9%). No baseline clinical features behaved as independent predictors of PCS development. CONCLUSIONS: A Post-acute COVID-19 syndrome was detected in a half of COVID19 survivors. Radiological and spirometric changes were mild and observed in less than 25% of patients. No baseline clinical features behaved as independent predictors of Post-acute COVID-19 syndrome development.

Hypokalemia as a sensitive biomarker of disease severity and the requirement for invasive mechanical ventilation requirement in COVID-19 pneumonia: A case series of 306 Mediterranean patients.

OBJECTIVES: Serum levels of potassium (K+) appear to be significantly lower in severe cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the clinical significance of this is unknown. The objective was to investigate whether hypokalemia acts as a biomarker of severity in coronavirus disease 2019 (COVID-19) pneumonia and is associated with major clinical outcomes. METHODS: A retrospective cohort study of inpatients with COVID-19 pneumonia (March 3 to May 2, 2020) was performed. Patients were categorized according to nadir levels of K+ in the first 72 h of admission: hypokalemia (K+ ≤3.5 mmol/l) and normokalemia (K+ >3.5 mmol/l). The main outcomes were all-cause mortality and the need for invasive mechanical ventilation (IMV); these were analyzed by multiple logistic regression (odds ratio (OR), 95% confidence interval (CI)). RESULTS: Three hundred and six patients were enrolled. Ninety-four patients (30.7%) had hypokalemia and these patients showed significantly higher comorbidity (Charlson comorbidity index ≥3, 30.0% vs 16.3%; p =  0.02) and CURB65 scores (median (interquartile range): 1.5 (0.0-3.0) vs 1.0 (0.0-2.0); p =  0.04), as well as higher levels of some inflammatory parameters at baseline. After adjustment for confounders, hypokalemia was independently associated with requiring IMV during the admission (OR 8.98, 95% CI 2.54-31.74). Mortality was 15.0% (n = 46) and was not influenced by low K+. Hypokalemia was associated with longer hospital and ICU stays. CONCLUSIONS: Hypokalemia is prevalent in patients with COVID-19 pneumonia. Hypokalemia is an independent predictor of IMV requirement and seems to be a sensitive biomarker of severe progression of COVID-19.

SARS-CoV-2 Codon Usage Bias Downregulates Host Expressed Genes With Similar Codon Usage.

Severe acute respiratory syndrome has spread quickly throughout the world and was declared a pandemic by the World Health Organization (WHO). The pathogenic agent is a new coronavirus (SARS-CoV-2) that infects pulmonary cells with great effectiveness. In this study we focus on the codon composition for the viral protein synthesis and its relationship with the protein synthesis of the host. Our analysis reveals that SARS-CoV-2 preferred codons have poor representation of G or C nucleotides in the third position, a characteristic which could result in an unbalance in the tRNAs pools of the infected cells with serious implications in host protein synthesis. By integrating this observation with proteomic data from infected cells, we observe a reduced translation rate of host proteins associated with highly expressed genes and that they share the codon usage bias of the virus. The functional analysis of these genes suggests that this mechanism of epistasis can contribute to understanding how this virus evades the immune response and the etiology of some deleterious collateral effect as a result of the viral replication. In this manner, our finding contributes to the understanding of the SARS-CoV-2 pathogeny and could be useful for the design of a vaccine based on the live attenuated strategy.

Experience with tocilizumab in severe COVID-19 pneumonia after 80 days of follow-up: A retrospective cohort study.

OBJECTIVES: To describe the clinical characteristics and predictors of major outcomes in patients treated with tocilizumab (TCZ) for severe COVID-19 pneumonia. PATIENTS AND METHODS: Case series of all sequential patients with severe COVID-19 pneumonia treated with TCZ at an Academic Spanish hospital (March 12 - May 2, 2020). Clinical outcomes: death, length of hospital stay. An early clinical response to TCZ (48-72 h after the administration) was assessed by variations in respiratory function markers, Brescia COVID Respiratory Severity Scale (BCRSS), inflammatory parameters, and patients' and physicians' opinion. Associations were tested by multiple logistic regression. RESULTS: From a cohort of 236 patients, 77 patients treated with TCZ were included (median age 62 years (IQR 53.0-72.0), 64.9% were males), 42.9% had Charlson index ≥3; hypertension (41.6%), obesity (34.7%), and diabetes (20.8%). Median follow-up was 83.0 days (78.0-86.5), no patient was readmitted. ICU admission was required for 42 (54.5%), invasive mechanical ventilation in 38 (49.4%) and 10 patients died (12.9% global, 23.8% at ICU admitted). After multivariate adjustment, TCZ response by BCRSS (OR 0.03 (0.01-0.68), p = 0.028), and Charlson index (OR 3.54 (1.20-10.44), p = 0.022) has been identified as independent factors associated with mortality. Median of hospital stay was 16.0 days (11.0-23.0); BCRSS, physician subjective and D-dimer response were associated with shorter hospitalization stay. CONCLUSIONS: In a Mediterranean cohort, use of tocilizumab for severe COVID-19 show 12.9% of mortality. Early TCZ-response by BCRSS and low comorbidity were associated with increased survival. Early TCZ-response was related to shorter median hospital stay.