Thin-Section Computed Tomography Manifestations During Convalescence and Long-Term Follow-Up of Patients with Severe Acute Respiratory Syndrome (SARS)

Individualized Homeopathic Medicinal Products in the Treatment of Post-COVID-19 Conditions: A Double-Blind, Randomized, Placebo-Controlled, Feasibility Trial

Objectives: Evidence suggests that post-coronavirus disease 2019 (COVID-19) is associated with reduced health-related quality of life, and up to 80% of those infected with COVID-19 may experience these symptoms. The objective of the present study was to identify the effects of individualized homeopathic medicinal products (IHMPs) against placebos in postCOVID-19 conditions. Design: Double-blind, randomized (1:1), two parallel arms, placebo-controlled, feasibility trial. Setting: D. N. De Homoeopathic Medical College & Hospital, Kolkata, West Bengal, India. Subjects: Sixty participants with post-COVID-19 conditions. Interventions: Group verum (n = 30; IHMPs plus concomitant care) versus group control (n = 30; placebos plus concomitant care). Outcome Measures: Feasibility issues; primary-post-COVID-19 symptoms checklist; secondary-Measure Yourself Medical Outcomes Profile version 2 (MYMOP-2); all of them were measured at baseline, and monthly intervals, up to 3 months. The intention-to-treat sample was analyzed; group differences were reported using descriptive statistics: means, 95% confidence intervals (CIs), and between group effect sizes (Cohen's d). Results: Feasibility concerns showed promise; recruitment, retention, and attrition rates were 34.2%, 95%, and 5%, respectively. Group differences in both primary and secondary outcomes favored IHMPs against placebos: symptoms checklist score mean difference after 3 months: -4.2, 95% CI -4.9 to -3.4, d = 2.854 and MYMOP-2 mean difference after 3 months: -2.2, 95% CI -2.8 to -1.7, d = 2.082, respectively. Natrum muriaticum (11.7%), Pulsatilla nigricans (10%), Rhus toxicodendron (8.3%), and Calcarea carbonica (8.3%) were the most frequently prescribed remedies. Conclusions: IHMPs produced better results than placebos in reducing symptoms checklist scores and MYMOP-2 scores in the treatment of post-COVID-19 conditions. Definitive trials are warranted to confirm the findings.

The Effects of a Pulmonary Rehabilitation Programme on Functional Capacity and Strength of Respiratory Muscles in Patients with Post-COVID Syndrome

Aim

The aim of this study was to estimate the effects of a pulmonary rehabilitation programme (PR) on the functional capacity and respiratory muscle strength of patients with post-COVID syndrome.

Methods

A cross-sectional study was conducted using hospital data on patients who participated in a pulmonary rehabilitation programme at the Clinic for Lung Diseases, University Hospital Centre Zagreb, Croatia, between January 2021 and December 2022. Data on the spirometry, respiratory muscle strength, and functional exercise capacity of patients were collected at baseline and three weeks after the start of rehabilitation. The study included 80 patients (43 females, 37 males) with a mean age of 51±10 years.

Results

A significant increase in respiratory muscle strength (P<0.001) was observed after pulmonary rehabilitation, with effect sizes ranging from small to large (Cohen's d from 0.39 to 1.07), whereas the effect for PImax expressed as a percentage was large (Cohen's d=0.99). In addition, the pulmonary rehabilitation programme significantly improved the parameters of the six-minute walk test in patients, and the parameters of lung function, FVC, FEV1, and DLCO also improved significantly after PR (P<0.05).

Conclusion

The results showed that the pulmonary rehabilitation programme has clinically significant effects on functional capacity and respiratory muscle strength in patients with post-COVID syndrome.

Modelling the long-term health impact of COVID-19 using Graphical Chain Models brief heading: long COVID prediction by graphical chain models

BACKGROUND

Long-term sequelae of SARS-CoV-2 infection, namely long COVID syndrome, affect about 10% of severe COVID-19 survivors. This condition includes several physical symptoms and objective measures of organ dysfunction resulting from a complex interaction between individual predisposing factors and the acute manifestation of disease. We aimed at describing the complexity of the relationship between long COVID symptoms and their predictors in a population of survivors of hospitalization for severe COVID-19-related pneumonia using a Graphical Chain Model (GCM).

METHODS

96 patients with severe COVID-19 hospitalized in a non-intensive ward at the "Santa Maria" University Hospital, Terni, Italy, were followed up at 3-6 months. Data regarding present and previous clinical status, drug treatment, findings recorded during the in-hospital phase, presence of symptoms and signs of organ damage at follow-up were collected. Static and dynamic cardiac and respiratory parameters were evaluated by resting pulmonary function test, echocardiography, high-resolution chest tomography (HRCT) and cardiopulmonary exercise testing (CPET).

RESULTS

Twelve clinically most relevant factors were identified and partitioned into four ordered blocks in the GCM: block 1 - gender, smoking, age and body mass index (BMI); block 2 - admission to the intensive care unit (ICU) and length of follow-up in days; block 3 - peak oxygen consumption (VO2), forced expiratory volume at first second (FEV1), D-dimer levels, depression score and presence of fatigue; block 4 - HRCT pathological findings. Higher BMI and smoking had a significant impact on the probability of a patient's admission to ICU. VO2 showed dependency on length of follow-up. FEV1 was related to the self-assessed indicator of fatigue, and, in turn, fatigue was significantly associated with the depression score. Notably, neither fatigue nor depression depended on variables in block 2, including length of follow-up.

CONCLUSIONS

The biological plausibility of the relationships between variables demonstrated by the GCM validates the efficacy of this approach as a valuable statistical tool for elucidating structural features, such as conditional dependencies and associations. This promising method holds potential for exploring the long-term health repercussions of COVID-19 by identifying predictive factors and establishing suitable therapeutic strategies.

Low Field MRI Surveillance 6-24 Months Post-acute COVID-19 Pneumonia: Factors Influencing Severity and Evolution of Lung Opacities

RATIONALE AND OBJECTIVES

To determine factors influencing low-field MRI lung opacity severity 6-24 months after acute Covid-19 pneumonia.

MATERIALS AND METHODS

104 post-acute Covid-19 patients with 167 MRI exams were included. 32 patients had more than one exam, and 63 exams were serial exams. Pulmonary findings were graded on a scale of 0-4 by quadrant, total score ranging from 0 (no opacity) to 16 (opacity > 75%), and score >8 considered moderate and >12 severe opacity. Kruskal-Wallis, Mann-Whitney, and Spearman rank correlation was used to assess the association of clinical and demographic factors with MR opacity severity at time intervals from acute infection. Random coefficients regression was used to assess whether opacity score changed over time.

RESULTS

Severity of initial illness was associated with increased MR opacity score at timeframes up to 24 months (p < .05). Among the 167 exams, moderate to severe MR opacities (total opacity score >8) were identified in 33% of exams beyond 6 months: 37% at 6 - <12 months (n = 23/63); 31% at 12- < 18 months (n = 13/42); 25% at 18- < 24 months (n = 6/24); and 50% at > 24 months (n = 3/6). No significant change in total opacity score over time was identified by random coefficients regression. Among the 32 patients with serial exams, 11 demonstrated no change in opacity score from initial to final exam, 10 decrease in score (mean 2.3, stdev 1.25, range 1-4), and 11 increase in score (average 2.8, stdev 1.48, range 1-7).

CONCLUSION

Initial Covid-19 disease severity was associated with increased MRI total opacity score at time intervals up to 24 months, and moderate to severe opacities were commonly identified by low-field MRI beyond 6 months from acute illness.

Pulmonary and renal long COVID at two-year revisit

This study investigated host responses to long COVID by following up with 89 of the original 144 cohorts for 1-year (N = 73) and 2-year visits (N = 57). Pulmonary long COVID, characterized by fibrous stripes, was observed in 8.7% and 17.8% of patients at the 1-year and 2-year revisits, respectively, while renal long COVID was present in 15.2% and 23.9% of patients, respectively. Pulmonary and renal long COVID at 1-year revisit was predicted using a machine learning model based on clinical and multi-omics data collected during the first month of the disease with an accuracy of 87.5%. Proteomics revealed that lung fibrous stripes were associated with consistent down-regulation of surfactant-associated protein B in the sera, while renal long COVID could be linked to the inhibition of urinary protein expression. This study provides a longitudinal view of the clinical and molecular landscape of COVID-19 and presents a predictive model for pulmonary and renal long COVID.

Long-term radiological and pulmonary function abnormalities at 3 years after COVID-19 hospitalisation: a longitudinal cohort study

BACKGROUND

This study aimed to evaluate the longitudinal progression of residual lung abnormalities (ground-glass opacities, reticulation and fibrotic-like changes) and pulmonary function at 3 years following coronavirus disease 2019 (COVID-19).

METHODS

This prospective, longitudinal cohort study enrolled COVID-19 survivors who exhibited residual lung abnormalities upon discharge from two hospitals. Follow-up assessments were conducted at 6 months, 12 months, 2 years and 3 years post-discharge, and included pulmonary function tests, 6-min walk distance (6MWD), chest computed tomography (CT) scans and symptom questionnaires. Non-COVID-19 controls were retrospectively recruited for comparative analysis.

RESULTS

728 COVID-19 survivors and 792 controls were included. From 6 months to 3 years, there was a gradual improvement in reduced diffusing capacity of the lung for carbon monoxide (D LCO <80% predicted: 49% versus 38%; p=0.001), 6MWD (496 versus 510 m; p=0.002) and residual lung abnormalities (46% versus 36%; p<0.001), regardless of disease severity. Patients with residual lung abnormalities at 3 years more commonly had respiratory symptoms (32% versus 16%; p<0.001), lower 6MWD (494 versus 510 m; p=0.003) and abnormal D LCO (57% versus 27%; p<0.001) compared with those with complete resolution. Compared with controls, the proportions of D LCO impairment (38% versus 17%; p<0.001) and respiratory symptoms (23% versus 2.2%; p<0.001) were significantly higher in the matched COVID-19 survivors at the 3-year follow-up.

CONCLUSIONS

Most patients exhibited improvement in radiological abnormalities and pulmonary function over time following COVID-19. However, more than a third continued to have persistent lung abnormalities at the 3-year mark, which were associated with respiratory symptoms and reduced diffusion capacity.

CT-based Assessment at 6-Month Follow-up of COVID-19 Pneumonia patients in China

This study aimed to assess pulmonary changes at 6-month follow-up CT and predictors of pulmonary residual abnormalities and fibrotic-like changes in COVID-19 pneumonia patients in China following relaxation of COVID restrictions in 2022. A total of 271 hospitalized patients with COVID-19 pneumonia admitted between November 29, 2022 and February 10, 2023 were prospectively evaluated at 6 months. CT characteristics and Chest CT scores of pulmonary abnormalities were compared between the initial and the 6-month CT. The association of demographic and clinical factors with CT residual abnormalities or fibrotic-like changes were assessed using logistic regression. Follow-up CT scans were obtained at a median of 177 days (IQR, 170-185 days) after hospital admission. Pulmonary residual abnormalities and fibrotic-like changes were found in 98 (36.2%) and 39 (14.4%) participants. In multivariable analysis of pulmonary residual abnormalities and fibrotic-like changes, the top three predictive factors were invasive ventilation (OR 13.6; 95% CI 1.9, 45; P < .001), age > 60 years (OR 9.1; 95% CI 2.3, 39; P = .01), paxlovid (OR 0.11; 95% CI 0.04, 0.48; P = .01) and invasive ventilation (OR 10.3; 95% CI 2.9, 33; P = .002), paxlovid (OR 0.1; 95% CI 0.03, 0.48; P = .01), smoker (OR 9.9; 95% CI 2.4, 31; P = .01), respectively. The 6-month follow-up CT of recent COVID-19 pneumonia cases in China showed a considerable proportion of the patients with pulmonary residual abnormalities and fibrotic-like changes. Antivirals against SARS-CoV-2 like paxlovid may be beneficial for long-term regression of COVID-19 pneumonia.

Algorithmic approach in the management of COVID-19 patients with residual pulmonary symptoms

Coronavirus-19 emerged about 3 years ago and has proven to be a devastating disease, crippling communities worldwide and accounting for more than 6.31 million deaths. The true disease burden of COVID-19 will come to light in the upcoming years as we care for COVID-19 survivors with post-COVID-19 syndrome (PCS) with residual long-term symptoms affecting every organ system. Pulmonary fibrosis is the most severe long-term pulmonary manifestation of PCS, and due to the high incidence of COVID-19 infection rates, PCS-pulmonary fibrosis has the potential of becoming the next large-scale respiratory health crisis. To confront the potentially devastating effects of emerging post-COVID-19 pulmonary fibrosis, dedicated research efforts are needed to focus on surveillance, understanding pathophysiologic mechanisms, and most importantly, an algorithmic approach to managing these patients. We have performed a thorough literature review on post-COVID-19 pulmonary symptoms/imaging/physiology and present an algorithmic approach to these patients based on the best available data and extensive clinical experience.

Long-term complications after infection with SARS-CoV-1, influenza and MERS-CoV - Lessons to learn in long COVID?

The COVID-19 pandemic has affected millions of people worldwide, and while the mortality rate remains the primary concern, it is becoming increasingly apparent that many COVID-19 survivors experience long-term sequelae, representing a major concern for both themselves and healthcare providers. Comparing long-term sequelae following COVID-19 to those of other respiratory viruses such as influenza, MERS-CoV, and SARS-CoV-1 is an essential step toward understanding the extent and impact of these sequelae. A literature search was carried out using the PubMed. database. Search-terms included "persistent", "long-term", "chronic", and MeSH-terms for SARS-CoV-1, MERS-CoV and Influenza. Only English-language articles were selected. Articles were screened by title/abstract and full-text readings. Key points for comparison were persistent symptoms > 4 weeks, virus type, study design, population size, admission status, methods, and findings. Thirty-one articles were included: 19 on SARS-CoV-1, 10 on influenza, and 2 on MERS-CoV-survivors. Damage to the respiratory system was the main long-term manifestation after the acute phase of infection. Quality of life-related and psychological sequelae were the second and third most widely reported symptoms, respectively. Consistent with long-term sequelae from COVID-19, persisting cardiovascular, neurological, musculoskeletal, gastrointestinal impairments were also reported. In summary, the long-term sequelae following COVID-19 are a significant concern, and while long-term sequelae following influenza, MERS-CoV, and SARS-CoV-1 have also been reported, their prevalence and severity are less clear. It is essential to continue to study and monitor the long-term effects of all respiratory viruses so as to improve our understanding and develop strategies for prevention and treatment.

What Remains up to 7 Months after Severe and Moderate Pneumonia in Non-Vaccinated Patients with Long COVID? Results of a CT Study

BACKGROUND

There is a growing evidence of long-lasting lung changes after COVID-19. Our aim was to assess the degree of lung injury and evaluate the recovery process of 4-7-month-non-vaccinated convalescent patients discharged from hospital after moderate and severe COVID-19 pneumonia, who presented with symptoms of long-COVID.

METHODS

On control lung CT after mean 5-month recovery period, we classified and determined the prevalence of residual radiological abnormalities in 39 symptomatic patients. To assess the advancement of the persisting changes we used the total severity score (TSS) and the chest CT score and then correlated the results with clinical data.

RESULTS AND CONCLUSIONS

On follow-up CT images, 94.9% of patients showed persistent radiological abnormalities. The most frequent changes were ground-glass opacities (74.4%), reticular pattern (64.1%), fibrotic changes (53.8%), nodules (33.3%), bronchiectasis (15.4%), vascular enlargement (10.3%), and cavitation (5.1%). The median TSS score was 4.1 points (interquartile range 3), whereas the median of the chest CT score 5.4 points (interquartile range of 4.5). No significant differences were observed between sex subgroups and between the severe and moderate course groups. There were no association between both CT scores and the severity of the initial disease, indicating that, mean 5 months after the disease, pulmonary abnormalities reduced to a similar stage in both subgroups of severity.

Multiomic characterisation of the long-term sequelae of SARS survivors: a clinical observational study

BACKGROUND

We aimed to characterise the long-term health outcomes of survivors of severe acute respiratory syndrome (SARS) and determine their recovery status and possible immunological basis.

METHODS

We performed a clinical observational study on 14 health workers who survived SARS coronavirus infection between Apr 20, 2003 and Jun 6, 2003 in Haihe Hospital (Tianjin, China). Eighteen years after discharge, SARS survivors were interviewed using questionnaires on symptoms and quality of life, and received physical examination, laboratory tests, pulmonary function tests, arterial blood gas analysis, and chest imaging. Plasma samples were collected for metabolomic, proteomic, and single-cell transcriptomic analyses. The health outcomes were compared 18 and 12 years after discharge. Control individuals were also health workers from the same hospital but did not infect with SARS coronavirus.

FINDINGS

Fatigue was the most common symptom in SARS survivors 18 years after discharge, with osteoporosis and necrosis of the femoral head being the main sequelae. The respiratory function and hip function scores of the SARS survivors were significantly lower than those of the controls. Physical and social functioning at 18 years was improved compared to that after 12 years but still worse than the controls. Emotional and mental health were fully recovered. Lung lesions on CT scans remained consistent at 18 years, especially in the right upper lobe and left lower lobe lesions. Plasma multiomics analysis indicated an abnormal metabolism of amino acids and lipids, promoted host defense immune responses to bacteria and external stimuli, B-cell activation, and enhanced cytotoxicity of CD8⁺ T cells but impaired antigen presentation capacity of CD4⁺ T cells.

INTERPRETATION

Although health outcomes continued to improve, our study suggested that SARS survivors still suffered from physical fatigue, osteoporosis, and necrosis of the femoral head 18 years after discharge, possibly related to plasma metabolic disorders and immunological alterations.

FUNDING

This study was funded by the Tianjin Haihe Hospital Science and Technology Fund (HHYY-202012) and Tianjin Key Medical Discipline (Specialty) Construction Project (TJYXZDXK-063B, TJYXZDXK-067C).

Longitudinal Assessment of Chest CT Findings and Pulmonary Function in Patients after COVID-19

Background Information on pulmonary sequelae and pulmonary function at 2 years post recovery from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are lacking. Purpose To longitudinally assess changes in chest CT abnormities and pulmonary function in patients after SARS-CoV-2 infection. Materials and Methods In this prospective study, patients discharged from the hospital after SARS-CoV-2 infection between January 15 and March 10, 2020 were considered for enrollment. Patients without chest CT scans on admission or with complete resolution of lung abnormities on discharge were excluded. Three serial chest CT scans and pulmonary function tests were obtained at 6 months (June 20-August 31, 2020), 12 months (December 20, 2020-February 3, 2021), and 2 years (November 16, 2021-January 10, 2022) after symptom onset. The term interstitial lung abnormalities (ILAs) and two subcategories, fibrotic ILAs and non-fibrotic ILAs, were used to describe the residual CT abnormalities on follow-up CT scans. Differences between groups were compared with χ², Fisher's exact test, or independent-samples t-test. Results Totally, 144 participants (median age, 60 [ranges 27-80] years; 79 men and 65 women) were included. On 2-year follow-up CT scans, 39% (56/144) of the subjects presented with ILAs, including 23% (33/144) wi fibrotic ILAs and 16% (23/144) with non-fibrotic ILAs. The remaining 88 cases (61%) showed complete radiological resolution. Over 2 years, the incidence of ILAs gradually decreased (54%, 42% and 39% at 6 months, 12 months and 2 years, respectively; P = .001). Respiratory symptoms (34% vs 15%, P =.007) and abnormal diffusing capacity of the lung for carbon monoxide (DLco,43% vs 20%, P = .004) more frequently occurred in participants with ILAs than those with complete radiological resolution. Conclusions More than one third of participants had persistent interstitial lung abnormalities at 2 years, which were associated with respiratory symptoms and decreased diffusion pulmonary function. See also the editorial by van Beek in this issue.

Parenchymal lung abnormalities following hospitalisation for COVID-19 and viral pneumonitis: a systematic review and meta-analysis

INTRODUCTION

Persisting respiratory symptoms in COVID-19 survivors may be related to development of pulmonary fibrosis. We assessed the proportion of chest CT scans and pulmonary function tests consistent with parenchymal lung disease in the follow-up of people hospitalised with COVID-19 and viral pneumonitis.

METHODS

Systematic review and random effects meta-analysis of proportions using studies of adults hospitalised with SARS-CoV-2, SARS-CoV, MERS-CoV or influenza pneumonia and followed up within 12 months. Searches performed in MEDLINE and Embase. Primary outcomes were proportion of radiological sequelae on CT scans; restrictive impairment; impaired gas transfer. Heterogeneity was explored in meta-regression.

RESULTS

Ninety-five studies (98.9% observational) were included in qualitative synthesis, 70 were suitable for meta-analysis including 60 SARS-CoV-2 studies with a median follow-up of 3 months. In SARS-CoV-2, the overall estimated proportion of inflammatory sequelae was 50% during follow-up (0.50; 95% CI 0.41 to 0.58; I2=95%), fibrotic sequelae were estimated in 29% (0.29; 95% CI 0.22 to 0.37; I2=94.1%). Follow-up time was significantly associated with estimates of inflammatory sequelae (-0.036; 95% CI -0.068 to -0.004; p=0.029), associations with fibrotic sequelae did not reach significance (-0.021; 95% CI -0.051 to 0.009; p=0.176). Impaired gas transfer was estimated at 38% of lung function tests (0.38 95% CI 0.32 to 0.44; I2=92.1%), which was greater than restrictive impairment (0.17; 95% CI 0.13 to 0.23; I2=92.5%), neither were associated with follow-up time (p=0.207; p=0.864).

DISCUSSION

Sequelae consistent with parenchymal lung disease were observed following COVID-19 and other viral pneumonitis. Estimates should be interpreted with caution due to high heterogeneity, differences in study casemix and initial severity.

PROSPERO REGISTRATION NUMBER

CRD42020183139.

Lung ultrasound in the follow-up of severe COVID-19 pneumonia: six months evaluation and comparison with CT

While lung ultrasonography (LUS) proved to be a useful diagnostic and prognostic tool in acute phase of COVID 19 pneumonia, its role in detecting long-term pulmonary sequelae has yet to be explored. In our prospective observational study we assessed the potential of LUS in detecting the presence of computed tomography (CT) fibrotic-like changes after 6 months from COVID-19 pneumonia. Patients who were discharged with a diagnosis of severe COVID-19 pneumonia were enrolled. After 6 months from hospital discharge they underwent LUS, chest CT scan and pulmonary function tests. A logistic regression analysis was performed to assess the association between presence of symptoms, LUS score and diffusing capacity for carbon monoxide (DLCO) at 6-month after hospital discharge and CT scan fibrotic-like changes. A second logistic model was performed to assess the value of some predefined baseline factors (age, sex, worst PaO2/FiO2, ventilator support, worst CRP value, worst D-dimer value and worst LUS score during hospitalization) to predict fibrotic-like changes on 6-month CT scan. Seventy-four patients were enrolled in the study. Twenty-four (32%) showed lung abnormalities suitable for fibrotic-like changes. At multivariate logistic regression analysis LUS score after 6 months from acute disease was significantly associated with fibrotic-like pattern on CT scan. The second logistic model showed that D-dimer value was the only baseline predictive variable of fibrotic-like changes at multivariate analysis. LUS performed after 6 months from severe COVID-19 pneumonia may be a promising tool for detection and follow-up of pulmonary fibrotic sequelae.

Physiotherapeutic evaluation of patients with post COVID-19 condition: current use of measuring instruments by physiotherapists working in Austria and South Tyrol

Background

The implementation of standardized assessments in physiotherapeutic practice strongly supports diagnostic and treatment plans. Previous studies reported insufficient usage of standardized assessments due to lack of time, lack of knowledge, lack of resources and other barriers. Physiotherapy in outpatient settings became essential for the rehabilitation of patients with post COVID-19 condition but it remains unknown to what extent assessments are implemented into the evaluation of these patients. In this study, we explored the current use and barriers regarding the implementation of physiotherapeutic assessments to evaluate patients with post COVID-19 condition.

Methods

A cross-sectional online survey was carried out among 180 physiotherapists working in outpatient settings in Austria and South Tyrol.

Results

The majority of physiotherapists (88%) indicated that standardized assessments are useful, though less than a fifth of participants actually implement assessments in practice. Among implementation barriers, “insufficient experience” (41.8%) and “lack of knowledge” (36.6%) were mentioned most often. Concerning specific post COVID-19 assessments, the evaluation of “physical and respiratory function”, “quality of life” and “activities of daily living” were stated to be of particular relevance.

Conclusions

Our study revealed a low implementation rate and identified the main barriers regarding the non-usage of standardized assessments for post COVID-19 patients.

Trial registration

The Private University for Health Sciences and Health Technology (UMIT TIROL), and the Research Committee for Scientific Ethical Questions granted approval for the survey (RCSEQ, Hall in Tirol, Austria, Number 2834).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40945-022-00147-0.

Differences and Similarities between the Lung Transcriptomic Profiles of COVID-19, COPD, and IPF Patients: A Meta-Analysis Study of Pathophysiological Signaling Pathways

Coronavirus disease 2019 (COVID-19) is a pandemic respiratory disease associated with high morbidity and mortality. Although many patients recover, long-term sequelae after infection have become increasingly recognized and concerning. Among other sequelae, the available data indicate that many patients who recover from COVID-19 could develop fibrotic abnormalities over time. To understand the basic pathophysiology underlying the development of long-term pulmonary fibrosis in COVID-19, as well as the higher mortality rates in patients with pre-existing lung diseases, we compared the transcriptomic fingerprints among patients with COVID-19, idiopathic pulmonary fibrosis (IPF), and chronic obstructive pulmonary disease (COPD) using interactomic analysis. Patients who died of COVID-19 shared some of the molecular biological processes triggered in patients with IPF, such as those related to immune response, airway remodeling, and wound healing, which could explain the radiological images seen in some patients after discharge. However, other aspects of this transcriptomic profile did not resemble the profile associated with irreversible fibrotic processes in IPF. Our mathematical approach instead showed that the molecular processes that were altered in COVID-19 patients more closely resembled those observed in COPD. These data indicate that patients with COPD, who have overcome COVID-19, might experience a faster decline in lung function that will undoubtedly affect global health.

One-year follow-up CT findings in COVID-19 patients: A systematic review and meta-analysis

Coronavirus disease 2019 (COVID‐19) often causes radiological and functional pulmonary sequelae. However, evidence on 1‐year follow‐up of pulmonary sequelae is limited. We aimed to investigate the characteristics and time‐course of pulmonary sequelae after recovery from COVID‐19 through 1‐year follow‐up. We searched PubMed and EMBASE databases on 25 February 2022, and included studies with computed tomography (CT) findings at the 1‐year follow‐up. The extracted data on CT findings were analysed using a one‐group meta‐analysis. We further analysed the data in relation to COVID‐19 severity, improvement rate and lung function. Fifteen eligible studies (N = 3134) were included. One year after COVID‐19, 32.6% (95% CI 24.0–42.6, I² = 92.9%) presented with residual CT abnormalities. Ground‐glass opacity and fibrotic‐like changes were frequently observed in 21.2% (95% CI 15.4–28.4, I² = 86.7%) and 20.6% (95% CI 11.0–35.2, I² = 91.9%), respectively. While the gradual recovery was seen on CT (52.9% [mid‐term] vs. 32.6% [1 year]), the frequency of CT abnormalities was higher in the severe/critical cases than in the mild/moderate cases (37.7% vs. 20.7%). In particular, fibrotic changes showed little improvement between 4–7 months and 1 year after COVID‐19. Pulmonary function tests at 1 year also showed the decline in diffusing capacity of the lung for carbon monoxide, especially in severe/critical cases. Our meta‐analysis indicated that residual CT abnormalities were common in hospitalized COVID‐19 patients 1 year after recovery, especially fibrotic changes in severe/critical cases. As these sequelae may last long, vigilant observations and longer follow‐up periods are warranted.

Pulmonary function test and computed tomography features during follow-up after SARS, MERS and COVID-19: a systematic review and meta-analysis

Background

The COVID-19 pandemic follows severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) coronavirus epidemics. Some survivors of COVID-19 infection experience persistent respiratory symptoms, yet their cause and natural history remain unclear. Follow-up after SARS and MERS may provide a model for predicting the long-term pulmonary consequences of COVID-19.

Methods

This systematic review and meta-analysis aims to describe and compare the longitudinal pulmonary function test (PFT) and computed tomography (CT) features of patients recovering from SARS, MERS and COVID-19. Meta-analysis of PFT parameters (DerSimonian and Laird random-effects model) and proportion of CT features (Freeman-Tukey transformation random-effects model) were performed.

Findings

Persistent reduction in the diffusing capacity for carbon monoxide following SARS and COVID-19 infection is seen at 6 months follow-up, and 12 months after MERS. Other PFT parameters recover in this time. 6 months after SARS and COVID-19, ground-glass opacity, linear opacities and reticulation persist in over 30% of patients; honeycombing and traction dilatation are reported less often. Severe/critical COVID-19 infection leads to greater CT and PFT abnormality compared to mild/moderate infection.

Interpretation

Persistent diffusion defects suggestive of parenchymal lung injury occur after SARS, MERS and COVID-19 infection, but improve over time. After COVID-19 infection, CT features are suggestive of persistent parenchymal lung injury, in keeping with a post-COVID-19 interstitial lung syndrome. It is yet to be determined if this is a regressive or progressive disease.

CT Lung Abnormalities after COVID-19 at 3 Months and 1 Year after Hospital Discharge

Background Data on the long-term pulmonary sequelae in COVID-19 are lacking. Purpose To assess symptoms, functional impairment, and residual pulmonary abnormalities on serial chest CT scans in COVID-19 survivors discharged from hospital at up to 1-year follow-up. Materials and Methods Adult patients with COVID-19 discharged between March 2020 and June 2020 were prospectively evaluated at 3 months and 1 year through systematic assessment of symptoms, functional impairment, and thoracic CT scans as part of the PHENOTYPE study, an observational cohort study in COVID-19 survivors. Lung function testing was limited to participants with CT abnormalities and/or persistent breathlessness. Bonferroni correction was used. Results Eighty participants (mean age, 59 years ± 13 [SD]; 53 men) were assessed. At outpatient review, persistent breathlessness was reported in 37 of the 80 participants (46%) and cough was reported in 17 (21%). CT scans in 73 participants after discharge (median, 105 days; IQR, 95-141 days) revealed persistent abnormalities in 41 participants (56%), with ground-glass opacification (35 of 73 participants [48%]) and bands (27 of 73 participants [37%]) predominating. Unequivocal signs indicative of established fibrosis (ie, volume loss and/or traction bronchiectasis) were present in nine of 73 participants (12%). Higher admission serum C-reactive protein (in milligrams per liter), fibrinogen (in grams per deciliter), urea (millimoles per liter), and creatinine (micromoles per liter) levels; longer hospital stay (in days); older age (in years); and requirement for invasive ventilation were associated with CT abnormalities at 3-month follow-up. Thirty-two of 41 participants (78%) with abnormal findings at 3-month follow-up CT underwent repeat imaging at a median of 364 days (range, 360-366 days), with 26 (81%) showing further radiologic improvement (median, 18%; IQR, 10%-40%). Conclusion CT abnormalities were common at 3 months after COVID-19 but with signs of fibrosis in a minority. More severe acute disease was linked with CT abnormalities at 3 months. However, radiologic improvement was seen in the majority at 1-year follow-up. ClinicalTrials.gov identifier: NCT04459351. © RSNA, 2022 Online supplemental material is available for this article.

Follow-Up CT Patterns of Residual Lung Abnormalities in Severe COVID-19 Pneumonia Survivors: A Multicenter Retrospective Study

Prior studies variably reported residual chest CT abnormalities after COVID-19. This study evaluates the CT patterns of residual abnormalities in severe COVID-19 pneumonia survivors. All consecutive COVID-19 survivors who received a CT scan 5–7 months after severe pneumonia in two Italian hospitals (Reggio Emilia and Parma) were enrolled. Individual CT findings were retrospectively collected and follow-up CT scans were categorized as: resolution, residual non-fibrotic abnormalities, or residual fibrotic abnormalities according to CT patterns classified following standard definitions and international guidelines. In 225/405 (55.6%) patients, follow-up CT scans were normal or barely normal, whereas in 152/405 (37.5%) and 18/405 (4.4%) patients, non-fibrotic and fibrotic abnormalities were respectively found, and 10/405 (2.5%) had post-ventilatory changes (cicatricial emphysema and bronchiectasis in the anterior regions of upper lobes). Among non-fibrotic changes, either barely visible (n = 110/152) or overt (n = 20/152) ground-glass opacities (GGO), resembling non-fibrotic nonspecific interstitial pneumonia (NSIP) with or without organizing pneumonia features, represented the most common findings. The most frequent fibrotic abnormalities were subpleural reticulation (15/18), traction bronchiectasis (16/18) and GGO (14/18), resembling a fibrotic NSIP pattern. When multiple timepoints were available until 12 months (n = 65), residual abnormalities extension decreased over time. NSIP, more frequently without fibrotic features, represents the most common CT appearance of post-severe COVID-19 pneumonia.

Dose-response relationship between risk factors and incidence of COVID-19 in 325 hospitalized patients: A multicenter retrospective cohort study

BACKGROUND

The epidemiological and clinical characteristics of coronavirus disease 2019 (COVID-19) patients have been widely reported, but the assessment of dose-response relationships and risk factors for mortality and severe cases and clinical outcomes remain unclear.

AIM

To determine the dose-response relationship between risk factors and incidence of COVID-19.

METHODS

In this retrospective, multicenter cohort study, we included patients with confirmed COVID-19 infection who had been discharged or had died by February 6, 2020. We used multivariable logistic regression and Cox proportional hazard models to determine the dose-response relationship between risk factors and incidence of COVID-19.

RESULTS

It clarified that increasing risk of in-hospital death were associated with older age (HR: 1.04, 95%CI: 1.01-1.09), higher lactate dehydrogenase [HR: 1.04, 95% confidence interval (CI): 1.01-1.10], C-reactive protein (HR: 1.10, 95%CI: 1.01-1.23), and procalcitonin (natural log-transformed HR: 1.88, 95%CI: 1.22-2.88), and D-dimer greater than 1 μg/mL at admission (natural log transformed HR: 1.63, 95%CI: 1.03-2.58) by multivariable regression. D-dimer and procalcitonin were logarithmically correlated with COVID-19 mortality risk, while there was a linear dose-response correlation between age, lactate dehydrogenase, D-dimer and procalcitonin, independent of established risk factors.

CONCLUSION

Higher lactate dehydrogenase, D-dimer, and procalcitonin levels were independently associated with a dose-response increased risk of COVID-19 mortality.

COVID-19 pneumonia imaging follow-up: when and how? A proposition from ESTI and ESR

This document from the European Society of Thoracic Imaging (ESTI) and the European Society of Radiology (ESR) discusses the role of imaging in the long-term follow-up of COVID-19 patients, to define which patients may benefit from imaging, and what imaging modalities and protocols should be used. Insights into imaging features encountered on computed tomography (CT) scans and potential pitfalls are discussed and possible areas for future review and research are also included. KEY POINTS: • Post-COVID-19 pneumonia changes are mainly consistent with prior organizing pneumonia and are likely to disappear within 12 months of recovery from the acute infection in the majority of patients. • At present, with the longest series of follow-up examinations reported not exceeding 12 months, the development of persistent or progressive fibrosis in at least some individuals cannot yet be excluded. • Residual ground glass opacification may be associated with persisting bronchial dilatation and distortion, and might be termed "fibrotic-like changes" probably consistent with prior organizing pneumonia.

One-year pulmonary impairment after severe COVID-19: a prospective, multicenter follow-up study

BACKGROUND

Long-term pulmonary sequelae following hospitalization for SARS-CoV-2 pneumonia is largely unclear. The aim of this study was to identify and characterise pulmonary sequelae caused by SARS-CoV-2 pneumonia at 12-month from discharge.

METHODS

In this multicentre, prospective, observational study, patients hospitalised for SARS-CoV-2 pneumonia and without prior diagnosis of structural lung diseases were stratified by maximum ventilatory support ("oxygen only", "continuous positive airway pressure (CPAP)" and "invasive mechanical ventilation (IMV)") and followed up at 12 months from discharge. Pulmonary function tests and diffusion capacity for carbon monoxide (DLCO), 6 min walking test, high resolution CT (HRCT) scan, and modified Medical Research Council (mMRC) dyspnea scale were collected.

RESULTS

Out of 287 patients hospitalized with SARS-CoV-2 pneumonia and followed up at 1 year, DLCO impairment, mainly of mild entity and improved with respect to the 6-month follow-up, was observed more frequently in the "oxygen only" and "IMV" group (53% and 49% of patients, respectively), compared to 29% in the "CPAP" group. Abnormalities at chest HRCT were found in 46%, 65% and 80% of cases in the "oxygen only", "CPAP" and "IMV" group, respectively. Non-fibrotic interstitial lung abnormalities, in particular reticulations and ground-glass attenuation, were the main finding, while honeycombing was found only in 1% of cases. Older patients and those requiring IMV were at higher risk of developing radiological pulmonary sequelae. Dyspnea evaluated through mMRC scale was reported by 35% of patients with no differences between groups, compared to 29% at 6-month follow-up.

CONCLUSION

DLCO alteration and non-fibrotic interstitial lung abnormalities are common after 1 year from hospitalization due to SARS-CoV-2 pneumonia, particularly in older patients requiring higher ventilatory support. Studies with longer follow-ups are needed.

Mesenchymal stem cell treatment for COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has caused a global pandemic since late 2019 that resulted in more than 360 million population infection. Among them, less than 7% of infected individuals develop severe or critical illness. Mass vaccination has been carried out, but reinfection and vaccine breakthrough cases still occur. Besides supportive and antiviral medications, much attention has been paid in immunotherapies that aim at reducing pathological changes in the lungs. Mesenchymal stem cells (MSCs) is used as an option because of their immunomodulatory, anti-inflammatory, and regenerative properties. As of January 16, 2022, when ClinicalTrials.gov was searched for "Mesenchymal stem cells and COVID-19," over 80 clinical trials were registered. MSC therapy was found to be safe and some effective in preclinical and clinical studies. Here, we summarize the major pathological characteristics of COVID-19 and provide scientific and rational evidence for the safety and possible effectiveness of MSCs in COVID-19 treatment.

How COVID-19 interacts with interstitial lung disease

The global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had far-reaching impacts on patients with interstitial lung disease (ILD), from diagnosis to management. In addition, after infection, persistent parenchymal change is associated with ongoing symptoms and functional impairment even in patients without pre-existing lung disease. The challenge of investigating and treating these patients has often fallen to ILD physicians. This review therefore seeks to explore the relationship between COVID-19 and the interstitium, as well as the model of care for patients with pre-existing ILD and those patients with persistent disease following recovery from their initial infection.

COVID-19 has had profound effects on patients with pre-existing interstitial lung disease, and there is growing interest in the effect on the lung parenchyma in patients recovering from acute infection. https://bit.ly/33M5s4x

Respiratory Complications after COVID-19

COVID-19 pandemic has been associated with high short-term morbidity and mortality. Lungs are the main organs affected by SARS-CoV-2 infection. In the long-term, the pulmonary sequelae related to COVID-19 are expected to rise significantly leading to an extended impact on community health and health care facilities. A wide variety of long-term respiratory complications secondary to COVID-19 have been described ranging from persistent symptoms and radiologically observable changes to impaired respiratory physiology, vascular complications, and pulmonary fibrosis. Even after two-years, respiratory sequalae related to post-acute SARS-CoV-2 infection have not been fully explored and understood. The main treatment for most COVID-19 respiratory complications is still symptomatic and supportive-care oriented. In this review article, we shed light on current knowledge of the post-COVID-19 complications, focusing on pulmonary fibrosis, treatment directions, and recommendations to physicians.

Isfahan COVID cohort study: Rationale, methodology, and initial results

BACKGROUND

The Isfahan COVID Cohort (ICC) study was designed to investigate the short- and long-term consequences of patients with COVID-19 in Iran. This report presents the rationale, methodology, and initial results of ICC.

MATERIALS AND METHODS

ICC is a 5-year multicentric prospective cohort study that is ongoing on two groups including 5000 patients hospitalized with moderate or severe and 800 nonhospitalized patients with mild or asymptomatic COVID-19 in Isfahan. The ICC endpoints are morbidity, mortality, incident cases, or worsening of underlying noncommunicable diseases (NCDs) and their risk factors. In the current analysis, we examined the persistent symptoms and incident NCDs or risk factors in 819 previously hospitalized patients who completed 1-year follow-up.

RESULTS

The two most common symptoms were joint pain/myalgia (19.7%) and dry cough/dyspnea (18.7%). Around 60% of patients had at least one symptom which was more common among women than men and in middle aged than younger or older patients. Female (odds ratio [OR] =1.88, 95% confidence interval [CI]: 1.39-2.55) and highly-educated patients (OR = 2.18, 95% CI: 1.56-3.04) had higher risk of having any symptom in 1-year follow-up. New cases of hypertension followed by diabetes then coronary heart disease (CHD) were the most common incident NCDs.

CONCLUSION

During 1-year follow-up after hospital discharge, about 60% of patients experienced persistent symptoms. Incident hypertension, diabetes, and CHD were the most common events seen. Close monitoring and extensive health services with integrative approaches are needed to improve the health status of these patients.

Imaging of COVID-19

The novel coronavirus disease 2019 (COVID-19) emerged as the source of a global pandemic in late 2019 and early 2020 and quickly spread throughout the world becoming one of the worst pandemics in recent history. This chapter reviews the most up to date radiological literature and outlines the utility of thoracic imaging in COVID-19, defining both the common and the less typical imaging appearances during the acute and subacute phases of COVID-19. The short term complications and the long term sequela will also be discussed in the context of radiology, including pulmonary emboli, acute respiratory distress syndrome, superimposed infections, barotrauma, cardiac manifestations, pulmonary parenchymal scarring and fibrosis.

OUP accepted manuscript

Objectives

Methods

Key findings

Conclusion

Long COVID, a comprehensive systematic scoping review

PURPOSE

To find out what is known from literature about Long COVID until January 30, 2021.

METHODS

We undertook a four-step search with no language restriction. A preliminary search was made to identify the keywords. A search strategy of all electronic databases resulted in 66 eligible studies. A forward and backward search of the references and citations resulted in additional 54 publications. Non-English language articles were translated using Google Translate. We conducted our scoping review based on the PRISMA-ScR Checklist.

RESULTS

Of 120 papers, we found only one randomized clinical trial. Of the 67 original studies, 22 were cohort, and 28 were cross-sectional studies. Of the total 120 publications, 49.1% focused on signs and symptoms, 23.3% on management, and 10.8% on pathophysiology. Ten publications focused on imaging studies. The results are also presented extensively in a narrative synthesis in separated sections (nomenclature, diagnosis, pathophysiology, risk factors, signs/symptoms, management).

CONCLUSIONS

The controversies in its definition have impaired proper recognition and management. The predominant symptoms were: fatigue, breathlessness, arthralgia, sleep difficulties, and chest pain. Recent reports also point to the risk of long-term sequela with cutaneous, respiratory, cardiovascular, musculoskeletal, mental health, neurologic, and renal involvement in those who survive the acute phase of the illness.

Sequelae of COVID-19 pneumonia: Is it correct to label everything as post-COVID lung fibrosis?

One of the common long-term consequences observed in survivors of COVID-19 pneumonia is the persistence of respiratory symptoms and/or radiological lung abnormalities. The exact prevalence of these post-COVID pulmonary changes is yet unclear. Few authors, based on their early observations, have labeled these persistent computed tomography (CT) abnormalities as post-COVID lung fibrosis, which appears to be an overstatement. Lately, it is being observed that many of the changes seen in post-COVID lungs are temporary and tend to show resolution on follow-up, with only a few developing into lung fibrosis. Thus, based on the presumptive diagnosis of lung fibrosis, these patients should not be blindly started on anti-fibrotic drugs. One must not forget that these drugs can do more harm than good, if used injudiciously. It is better to use the term “post-COVID interstitial lung changes”, which covers a broader spectrum of pulmonary changes seen in patients who have recovered from COVID-19 pneumonia. At the same time, it is essential to identify the sub-set of COVID-19 survivors who are at an increased risk of developing lung fibrosis and to carefully chalk out management strategies so as to modify the course of the disease and prevent irreversible damage. Meticulous and systematic longitudinal follow-up studies consisting of clinical, laboratory, imaging, and pulmonary function tests are needed for the exact estimation of the burden of lung fibrosis, to understand the nature of residual pulmonary changes, and to predict the likelihood of development of lung fibrosis in COVID-19 survivors.

Short-term follow-up HRCT Chest of COVID-19 survivors and association with persistent dyspnea

Background

There is an increasing concern that a proportion of the survivors of COVID 19 might develop fibrotic and/or other non-reversible lung changes. The aim of this retrospective study was to review the imaging findings of HRCT of lungs in a cohort of COVID 19 survivors, coming for short-term clinical follow-up and to assess the relation of the observed HRCT changes with the presence of dyspnea.

Results

In total, 40 patients with residual CT findings were included in this study with a mean age of 44.3 years and male: female ratio of 3:2. The presence of residual ground-glass opacities (85%) and reticular opacities (80%) was the most common findings. 25% of the cases had cystic changes in their lung. The presence of dyspnea was significantly associated with male sex and a history of smoking. On HRCT, the presence of cystic changes, involvement of > 10 lung segments, and an HRCT severity score > 7 were significantly associated with dyspnea.

Conclusion

Survivors of COVID 19 demonstrate persistent changes in the lung on HRCT. We recommend that a follow-up HRCT should be performed in these patients to identify those with post-COVID sequelae.

Longitudinal Assessment of Health and Quality of Life of COVID-19 Patients Requiring Intensive Care-An Observational Study

Long-term health consequences in survivors of severe COVID-19 remain unclear. Eighteen COVID-19 patients admitted to the intensive care unit at the University Hospital Rechts der Isar, Munich, Germany, between 14 March and 23 June 2020, were prospectively followed-up at a median of 36, 75.5, 122 and 222 days after discharge. The health-related quality of life (HrQoL) (36-item Short Form Health Survey and St. George’s Respiratory Questionnaire, SGRQ), cardiopulmonary function, laboratory parameters and chest imaging were assessed longitudinally. The HrQoL assessment revealed a reduced physical functioning, as well as increased SGRQ impact and symptoms scores that all improved over time but remained markedly impaired compared to the reference groups. The median radiological severity scores significantly declined; persistent abnormalities were found in 33.3% of the patients on follow-up. A reduced diffusion capacity was the most common abnormal pulmonary function parameter. The length of hospitalization correlated with role limitations due to physical problems, the SGRQ symptom and the impact score. In conclusion, in survivors of severe COVID-19, the pulmonary function and symptoms improve over time, but impairments in their physical function and diffusion capacity can persist over months. Longer follow-up studies with larger cohorts will be necessary to comprehensively characterize long-term sequelae upon severe COVID-19 and to identify patients at risk.

Follow-Up Study of the Cardiopulmonary and Psychological Outcomes of COVID-19 Survivors Six Months After Discharge in Sichuan, China

PURPOSE

Some studies have shown that patients with coronavirus disease 2019 (COVID-19) still have sequelae after discharge. However, little is known about the long-term physical and psychological sequelae of patients, especially factors that influenced the prognosis.

PATIENTS AND METHODS

Patients with COVID-19 were followed up for 6 months. The psychological status of patients was evaluated by DASS-21 questionnaire, while physical functions were determined using medical history, laboratory examination, thoracic computed tomography (CT), and echocardiography.

RESULTS

Fifty patients infected with COVID-19 were enrolled, and 11 (22%) patients still showed symptoms related to COVID-19. The mean contents (cells/ul) of CD3+ cells, CD4+ and CD8+ T, B lymphocytes and NK cells of the survivors elevated significantly after 6-month discharge (P < 0.001). The frequency of ground-glass opacities and consolidations decreased from 90% to 42% (P < 0.001), and 54% to 20%, (P = 0.001), respectively, while the changes of reticulation and bronchiectasis were insignificant (P > 0.05). The frequency of left ventricular diastolic dysfunction decreased from 40% to 15% (P = 0.002). Depression was observed in 5 (12.5%) participants, stress in 3 (7.5%), anxiety in 6 (15%), and among them 1 (2.5%) showed extremely severe anxiety. Covariation analysis elucidated age might be a risk factor (OR: 1.09, 95% CI: 1.01-1.18, P = 0.038), while NK cell was a good prognostic factor for pulmonary recovery. The comorbidities were significantly positive correlated with persist pulmonary damage (r = 0.33, P = 0.020). Compared with patients with antiviral therapy, patients without antiviral therapy had higher anxiety score (3 vs 0, P = 0.033).

CONCLUSION

After 6-month discharge, the persisting cardiopulmonary damage was observed in recovery patients, and psychological implications should not be ignored. Age, comorbidities, NK cell and antiviral therapy might be associated with the prognosis of COVID-19.

Preliminary Evidence for IL-10-Induced ACE2 mRNA Expression in Lung-Derived and Endothelial Cells: Implications for SARS-Cov-2 ARDS Pathogenesis

Angiotensin-converting enzyme 2 (ACE2) is a receptor for the spike protein of SARS-COV-2 that allows viral binding and entry and is expressed on the surface of several pulmonary and non-pulmonary cell types, with induction of a “cytokine storm” upon binding. Other cell types present the receptor and can be infected, including cardiac, renal, intestinal, and endothelial cells. High ACE2 levels protect from inflammation. Despite the relevance of ACE2 levels in COVID-19 pathogenesis, experimental studies to comprehensively address the question of ACE2 regulations are still limited. A relevant observation from the clinic is that, besides the pro-inflammatory cytokines, such as IL-6 and IL-1β, the anti-inflammatory cytokine IL-10 is also elevated in worse prognosis patients. This could represent somehow a “danger signal”, an alarmin from the host organism, given the immuno-regulatory properties of the cytokine. Here, we investigated whether IL-10 could increase ACE2 expression in the lung-derived Calu-3 cell line. We provided preliminary evidence of ACE2 mRNA increase in cells of lung origin in vitro, following IL-10 treatment. Endothelial cell infection by SARS-COV-2 is associated with vasculitis, thromboembolism, and disseminated intravascular coagulation. We confirmed ACE2 expression enhancement by IL-10 treatment also on endothelial cells. The sartans (olmesartan and losartan) showed non-statistically significant ACE2 modulation in Calu-3 and endothelial cells, as compared to untreated control cells. We observed that the antidiabetic biguanide metformin, a putative anti-inflammatory agent, also upregulates ACE2 expression in Calu-3 and endothelial cells. We hypothesized that IL-10 could be a danger signal, and its elevation could possibly represent a feedback mechanism fighting inflammation. Although further confirmatory studies are required, inducing IL-10 upregulation could be clinically relevant in COVID-19-associated acute respiratory distress syndrome (ARDS) and vasculitis, by reinforcing ACE2 levels.

Exploring the scope of homoeopathy in combating the unfortunate consequences of post-COVID-19 survivors based on non-COVID conditions: a narrative review

OBJECTIVES

The long-term consequences of COVID-19 survivors care and post-coronavirus infection are not yet well understood. The review aims to see whether homoeopathy can help COVID-19 survivors recover from its consequences and improve their quality of life.

CONTENT

A systematic search of published articles for post-COVID sequelae and the impact of Homoeopathy were conducted. For the literature search, the major electronic bio-medical database PubMed/MEDLINE was used. In addition, supplementary searches were conducted through the references of those published articles.

SUMMARY

A total of 113 records were identified of which 61 studies included for this review. Homoeopathy is effective in the treatment of mental disorders including anxiety and depressive disorder (ADD), some research studies have found, although systematic reviews disagree. Likewise, some medical societies denounce homoeopathy for pain management; other literature shows that it can be used to treat pain effectively. Homoeopathy can aid in the treatment of cardiovascular diseases, as Crataegus, a homoeopathic medication, was found to be just as effective as a standard angiotensin-converting enzyme (ACE) inhibitor and diuretic treatment for minor cardiac insufficiency. The outcomes for Chronic Fatigue Syndrome (CFS), Influenza, and Acute Respiratory Tract Infections (ARTIs) are also promising.

OUTLOOK

Based on the results of homoeopathy in non-COVID conditions, it can be thought of in the management of post-COVID-19 outcomes. Consequently, we propose that while investigating post-COVID-19 patient rehabilitation, homoeopathic management may be included as part of the follow-up route and as much data as possible in the context of homoeopathy should be collected, so that in future, the role of homoeopathy in dealing with it can be better demonstrated.

Chest CT Patterns from Diagnosis to 1 Year of Follow-up in COVID-19

Background

The chest CT manifestations of COVID-19 from hospitalization to convalescence after 1 year are unknown.

Purpose

To assess chest CT manifestations of COVID-19 up to 1 year after symptom onset.

Materials and Methods

Patients were enrolled if they were admitted to the hospital because of COVID-19 and underwent CT during hospitalization at two isolation centers between January 27, 2020, and March 31, 2020. In a prospective study, three serial chest CT scans were obtained at approximately 3, 7, and 12 months after symptom onset and were longitudinally analyzed. The total CT score of pulmonary lobe involvement, ranging from 0 to 25, was assessed (score of 1–5 for each lobe). Univariable and multivariable logistic regression analyses were performed to explore independent risk factors for residual CT abnormalities after 1 year.

Results

A total of 209 study participants (mean age, 49 years ± 13 [standard deviation]; 116 women) were evaluated. CT abnormalities had resolved in 61% of participants (128 of 209) at 3 months and in 75% of participants (156 of 209) at 12 months. Among participants with chest CT abnormalities that had not resolved, there were residual linear opacities in 25 of the 209 participants (12%) and multifocal reticular or cystic lesions in 28 of the 209 participants (13%). Age 50 years or older, lymphopenia, and severe or aggravation of acute respiratory distress syndrome were independent risk factors for residual CT abnormalities at 1 year (odds ratios = 15.9, 18.9, and 43.9, respectively; P < .001 for each comparison). In 53 participants with residual CT abnormalities at 12 months, reticular lesions (41 of 53 participants [77%]) and bronchial dilation (39 of 53 participants [74%]) were observed at discharge and were persistent in 28 (53%) and 24 (45%) of the 53 participants, respectively.

Conclusion

One year after COVID-19 diagnosis, chest CT scans showed abnormal findings in 53 of the 209 study participants (25%), with 28 of the 209 participants (13%) showing subpleural reticular or cystic lesions. Older participants with severe COVID-19 or acute respiratory distress syndrome were more likely to develop lung sequelae that persisted at 1 year.

© RSNA, 2021

Online supplemental material is available for this article.

See also the editorial by Lee and Wi et al in this issue.

Changes in the respiratory function of COVID-19 survivors during follow-up: A novel respiratory disorder on the rise?

BACKGROUND

The Human Coronavirus Disease 2019 (COVID-19) is a highly contagious respiratory disorder that may result in acute respiratory distress syndrome. The aim of this review was to investigate the incidence and type of respiratory function abnormalities during the follow-up of patients who recovered from COVID-19.

METHODS

A systematic search of MEDLINE was conducted, utilising various term combinations. Studies that assessed any respiratory function parameter during the re-evaluation of patients who recovered from COVID-19 and were published as full-text articles in English are included in this review.

RESULTS

Amongst 183 articles initially retrieved, 8 fulfilled the criteria and were included in this review; they involved a total of 341 adult patients. Four were retrospective studies, one was a prospective cohort study, one was a randomised control trial and two were case reports/case series. The follow-up time ranged from 1 month since symptom onset to 3 months after discharge. The most frequent abnormality was reduced lung diffusion for carbon monoxide (DLCO), followed by a restrictive pattern. Other findings are the lack of resting hypoxemia, the reduced respiratory muscle strength and the decreased exercise capacity, although relative data are extremely limited.

CONCLUSION

Patients who recovered from COVID-19 present with abnormal respiratory function at short-term follow-up, mainly with reduced lung diffusion and a restrictive pattern. However, results are currently very limited in order safe conclusions to be made, regarding the exact incidence of these abnormalities and whether they may be temporary or permanent.

Follow up for COVID-19 in Belfast City Hospital

BACKGROUND

During the COVID-19 pandemic of Spring 2020, Belfast City Hospital functioned as Belfast's Nightingale facility. Evidence published during this time focused mainly on the acute management of the condition. Guidance on follow up and long-term management for patients recovering from COVID-19 was sparse. A specialist COVID-19 follow up service was devised in Belfast City Hospital led by a respiratory physician with physiotherapy and psychology input.

METHODS

Data was collected on all patients admitted to Belfast Nightingale unit. Patients admitted to Intensive Care at any stage in their admission were followed up separately by Intensive Care. Initial consultation was via telephone call for all eligible patients six weeks post discharge, followed by face-to-face consultation for those with symptoms at next available appointment, and a further face-to-face consultation at twelve weeks post hospital discharge. Patients were seen by respiratory physician, physiotherapy and psychology at each appointment. All patients who had initial changes on chest radiograph had 12 week follow up radiograph requested as per British Thoracic Society guidelines.

RESULTS

29 patients were followed up after hospitalisation with COVID-19. Of these, 10 were brought for face-to-face consultations. Patients at clinic were all functionally independent with a median Medical Research Council dyspnoea score of 2 and a subjective assessment of their current health of median 50, on a visual analogue scale 0-100. Fatigue was common with all patients. Depression, anxiety and post-traumatic stress disorder were all reported from psychological review. Chest radiograph showed signs of improvement in 100% of clinic attendees. 90% of patients seen in clinic had normal or chronic obstructive patterns on spirometry, with one patient having a reduced transfer factor.

CONCLUSION

Majority of patients did not require face-to-face review and were recovering well. Of the 10 patients seen in the respiratory led clinic, the main issues reported were fatigue and psychological issues. Respiratory symptoms were significantly improving in 9 out of the 10 patients seen. All patients have been introduced to psychology service whilst at clinic and will continue to receive necessary support.

Postacute Sequelae of COVID-19 Pneumonia: 6-month Chest CT Follow-up

Background

The long-term post acute pulmonary sequelae of COVID-19 remain unknown.

Purpose

To evaluate lung injury in patients affected by COVID-19 pneumonia at six-month follow-up compared to baseline chest CT.

Methods

From March 19th,2020 to May 24th,2020, patients with moderate to severe COVID-19 pneumonia and baseline Chest CT were prospectively enrolled at six-months follow-up. CT qualitative findings, semi-quantitative Lungs Severity Score (LSS) and well-aerated lung quantitative Chest CT (QCCT) were analyzed. Baseline LSS and QCCT performances in predicting fibrotic-like changes (reticular pattern and/or honeycombing) at six-month follow-up Chest CT were tested with receiver operating characteristic curves. Univariable and multivariable logistic regression analysis were used to test clinical and radiological features predictive of fibrotic-like changes. The multivariable analysis was performed with clinical parameters alone (clinical model), radiological parameters alone (radiological model) and the combination of clinical and radiological parameters (combined model).

Results

One-hundred-eighteen patients, with both baseline and six-month follow-up Chest CT, were included in the study (62 female, mean age 65±12 years). At follow-up Chest CT, 85/118 (72%) patients showed fibrotic-like changes and 49/118 (42%) showed GGOs. Baseline LSS (>14), QCCT (≤3.75L and ≤80%) showed an excellent performance in predicting fibrotic-like changes at Chest CT follow-up. In the multivariable analysis, AUC was .89 (95%CI .77-.96) for the clinical model, .81 (95%CI .68-.9) for the radiological model and .92 (95%CI .81-.98)for the combined model.

Conclusion

At six-month follow-up Chest CT, 72% of patients showed late sequelae, in particular fibrotic-like changes. Baseline LSS and QCCT of well-aerated lung showed an excellent performance in predicting fibrotic-like changes at six-month Chest CT (AUC>.88). Male sex, cough, lymphocytosis and QCCT well-aerated lung were significant predictors of fibrotic-like changes at six-month with an inverse correlation (AUC .92).

See also the editorial by Wells and Devaraj.

Persistent Poor Health after COVID-19 Is Not Associated with Respiratory Complications or Initial Disease Severity

Rationale: Much is known about the acute infective process of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative virus of the coronavirus disease (COVID-19) pandemic. The marked inflammatory response and coagulopathic state in acute SARS-CoV-2 infection may promote pulmonary fibrosis. However, little is known about the incidence and seriousness of post-COVID-19 pulmonary pathology. Objectives: To describe the respiratory recovery and self-reported health after infection at the time of outpatient attendance. Methods: Infection severity was graded into three groups: 1) not requiring admission, 2) requiring hospital admission, and 3) requiring intensive care unit care. Participants underwent chest radiography and a 6-minute walk test (6MWT). Fatigue and subjective return to health were assessed, and concentrations of CRP (C-reactive protein), IL-6 (interleukin-6), sCD25 (soluble CD25), and D-dimer were measured. The associations between initial illness and abnormal chest X-ray findings, 6MWT distance, and perception of maximal exertion were investigated. Results: A total of 487 patients were offered an outpatient appointment, of whom 153 (31%) attended for assessment at a median of 75 days after diagnosis. A total of 74 (48%) had required hospital admission during acute infection. Persistently abnormal chest X-ray findings were seen in 4%. The median 6MWT distance covered was 460 m. A reduced distance covered was associated with frailty and length of inpatient stay. A total of 95 (62%) patients believed that they had not returned to full health, whereas 47% met the case definition for fatigue. Ongoing ill health and fatigue were associated with an increased perception of exertion. None of the measures of persistent respiratory disease were associated with initial disease severity. Conclusions: This study highlights the rates of objective respiratory disease and subjective respiratory symptoms after COVID-19 and the complex multifactorial nature of post-COVID-19 ill health.

Duration and Risk Factors of Post-COVID Symptoms Following Recovery Among the Medical Doctors in Bangladesh

A large number of coronavirus disease 2019 (COVID-19) recovered patients are suffering from related symptoms. We conducted telephone interviews with 186 COVID-19 recovered medical doctors to determine the post-COVID symptoms, duration, and associated risk factors. About 70% of participants had at least one acute post-COVID symptom, including fatigue (43.0%), sleep disturbance (13.4%), lack of concentration (11.8%), breathing difficulty (10.2%), headache (6.5%), and muscle pain (6.5%). However, about 24% of participants reported having long post-COVID symptoms. Logistic regression analysis showed that female sex (odds ratio {OR}, 2.79; 95% CI, 1.28-6.06; p-value: 0.010) and comorbid conditions (OR, 2.28; 95% CI, 1.08-4.79; p: value, 0.030) are risk factors for the long post-COVID symptoms.

Mesenchymal Stromal Cell Secretome for Post-COVID-19 Pulmonary Fibrosis: A New Therapy to Treat the Long-Term Lung Sequelae?

To date, more than 100 million people worldwide have recovered from COVID-19. Unfortunately, although the virus is eradicated in such patients, fibrotic irreversible interstitial lung disease (pulmonary fibrosis, PF) is clinically evident. Given the vast numbers of individuals affected, it is urgent to design a strategy to prevent a second wave of late mortality associated with COVID-19 PF as a long-term consequence of such a devastating pandemic. Available antifibrotic therapies, namely nintedanib and pirfenidone, might have a role in attenuating profibrotic pathways in SARS-CoV-2 infection but are not economically sustainable by national health systems and have critical adverse effects. It is our opinion that the mesenchymal stem cell secretome could offer a new therapeutic approach in treating COVID-19 fibrotic lungs through its anti-inflammatory and antifibrotic factors.

Predicting lung fibrosis in post-COVID-19 patients after discharge with follow-up chest CT findings

Background

Coronavirus disease has spread widely all over the world since the beginning of 2020, and this required rapid adequate management. High-resolution computed tomography (HRCT) has become an initial valuable tool for screening, diagnosis, and assessment of disease severity. This study aimed to assess the clinical, radiographic, and laboratory findings of COVID-19 with HRCT follow-up in discharged patients to predict lung fibrosis after COVID-19 infection in survived patients.

Results

This study included two-hundred and ten patients who were tested positive for the novel coronavirus by nasopharyngeal swap, admitted to the hospital, and discharged after recovery. Patients with at least a one-time chest CT scan after discharge were enrolled. According to the presence of fibrosis on follow-up CT after discharge, patients were classified into two groups and assigned as the “non-fibrotic group” (without evident fibrosis) and “fibrotic group” (with evident fibrosis). We compared between these two groups based on the recorded clinical data, patient demographic information (i.e., sex and age), length of stay (LOS) in the hospital, admission to the ICU, laboratory results (peak C-reactive protein [CRP] level, lowest lymphocyte level, serum ferritin, high-sensitivity troponin, d-dimer, administration of steroid), and CT features (CT severity score and CT consolidation/crazy-paving score). CT score includes the CT during the hospital stay with peak opacification and follow-up CT after discharge. The average CT follow-up time after discharge is 41.5 days (range, 20 to 65 days). There was a statistically significant difference between both groups (p ˂0.001). Further, a multivariate analysis was performed and found that the age of the patients, initial CT severity score, consolidation/crazy-paving score, and ICU admission were independent risk factors associated with the presence of post-COVID-19 fibrosis (p<0.05). Chest CT severity score shows a sensitivity of 86.1%, a specificity of 78%, and an accuracy of 81.9% at a cutoff point of 10.5.

Conclusion

The residual pulmonary fibrosis in COVID-19 survivors after discharge depends on many factors with the patient’s age, CT severity, consolidation/crazy-paving scores, and ICU admission as independent risk factors associated with the presence of post-COVID-19 fibrosis.

Clinical, radiological and functional outcomes in patients with SARS-CoV-2 pneumonia: a prospective observational study

BACKGROUND

All over the world, SARS-CoV-2 pneumonia is causing a significant short-term morbidity and mortality, but the medium-term impact on lung function and quality of life of affected patients are still unknown.

METHODS

In this prospective observational study, 39 patients with SARS-CoV-2 pneumonia were recruited from a single COVID-19 hospital in Southern Switzerland. At three months patients underwent radiological and functional follow-up through CT scan, lung function tests, and 6 min walking test. Furthermore, quality of life was assessed through self-reported questionnaires.

RESULTS

Among 39 patients with SARS-CoV-2 pneumonia, 32 (82% of all participants) presented abnormalities in CT scan and 25 (64.1%) had lung function tests impairment at three months. Moreover, 31 patients (79.5%) reported a perception of poor health due to respiratory symptoms and all 39 patients showed an overall decreased quality of life.

CONCLUSIONS

Medium-term follow up at three months of patients diagnosed with SARS-CoV-2 pneumonia shows the persistence of abnormalities in CT scans, a significant functional impairment assessed by lung function tests and a decreased quality of life in affected patients. Further studies evaluating the long-term impact are warranted to guarantee an appropriate follow-up to patients recovering from SARS-CoV-2 pneumonia.

Recent Findings on Cell-Based Therapies for COVID19-Related Pulmonary Fibrosis

COVID-19 has spread worldwide, including the United States, United Kingdom, and Italy, along with its site of origin in China, since 2020. The virus was first found in the Wuhan seafood market at the end of 2019, with a controversial source. The clinical symptoms of COVID-19 include fever, cough, and respiratory tract inflammation, with some severe patients developing an acute and chronic lung injury, such as acute respiratory distress syndrome (ARDS) and pulmonary fibrosis (PF). It has already claimed approximately 300 thousand human lives and the number is still on the rise; the only way to prevent the infection is to be safe till vaccines and reliable treatments develop. In previous studies, the use of mesenchymal stem cells (MSCs) in clinical trials had been proven to be effective in immune modulation and tissue repair promotion; however, their efficacy in treating COVID-19 remains underestimated. Here, we report the findings from past experiences of SARS and MSCs, and how SARS could also induce PF. Such studies may help to understand the rationale for the recent cell-based therapies for COVID-19.

SARS-CoV-2 reinfection: "New baseline" imaging concept in the era of COVID-19

Recent reports have suggested COVID-19 relapse or reinfection may lead to readmission, which may cause a diagnostic challenge between recently infected patients and reinfections. Compounding this problem is the post-viral lung sequela that may be expected after COVID-19 pneumonia, similar to both SARS and MERS. Although chest imaging may play a role in the diagnosis of primary SARS-CoV-2 infection, reinfection or relapse of COVID-19 will have similar imaging findings. A “new-baseline” imaging can be obtained from COVID-19 patients at the time of hospital discharge or clinical recovery. This new reference can not only determine if readmissions are from relapse or reinfection of COVID-19, resolving COVID-19 or potentially a different viral infection (influenza), but also for long term sequela of COVID-19 lung infection. Strategic use of imaging before discharge may be helpful in the subset of the population at the highest risk of a secondary viral infection such as influenza. Determining the residual abnormalities in post-discharge imaging can guide us in the long-term management of patients for many years to come.

Radiological and functional lung sequelae of COVID-19: a systematic review and meta-analysis

BACKGROUND

The coronavirus disease 2019 (COVID-19) causes a wide spectrum of lung manifestations ranging from mild asymptomatic disease to severe respiratory failure. We aimed to clarify the characteristics of radiological and functional lung sequelae of COVID-19 patients described in follow-up period.

METHOD

PubMed and EMBASE were searched on January 20th, 2021 to investigate characteristics of lung sequelae in COVID-19 patients. Chest computed tomography (CT) and pulmonary function test (PFT) data were collected and analyzed using one-group meta-analysis.

RESULTS

Our search identified 15 eligible studies with follow-up period in a range of 1-6 months. A total of 3066 discharged patients were included in these studies. Among them, 1232 and 1359 patients were evaluated by chest CT and PFT, respectively. The approximate follow-up timing on average was 90 days after either symptom onset or hospital discharge. The frequency of residual CT abnormalities after hospital discharge was 55.7% (95% confidential interval (CI) 41.2-70.1, I² = 96.2%). The most frequent chest CT abnormality was ground glass opacity in 44.1% (95% CI 30.5-57.8, I² = 96.2%), followed by parenchymal band or fibrous stripe in 33.9% (95% CI 18.4-49.4, I² = 95.0%). The frequency of abnormal pulmonary function test was 44.3% (95% CI 32.2-56.4, I² = 82.1%), and impaired diffusion capacity was the most frequently observed finding in 34.8% (95% CI 25.8-43.8, I² = 91.5%). Restrictive and obstructive patterns were observed in 16.4% (95% CI 8.9-23.9, I² = 89.8%) and 7.7% (95% CI 4.2-11.2, I² = 62.0%), respectively.

CONCLUSIONS

This systematic review suggested that about half of the patients with COVID-19 still had residual abnormalities on chest CT and PFT at about 3 months. Further studies with longer follow-up term are warranted.