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

Thin-section computed tomography findings and longitudinal variations of the residual pulmonary sequelae after discharge in patients with COVID-19: a short-term follow-up study

OBJECTIVES

This study analyzed and compared CT findings and longitudinal variations after discharge between severe and non-severe coronavirus disease (COVID-19) patients who had residual pulmonary sequelae at pre-discharge.

METHODS

A total of 310 patients were included and stratified into severe and non-severe COVID-19 groups. Cross-sectional CT features across different time periods (T0: pre-discharge, T1: 1-4 weeks after discharge, T2: 5-8 weeks after discharge, T3: 9-12 weeks after discharge, T4: > 12 weeks after discharge) were compared, and the longitudinal variations of CT findings were analyzed and compared in both groups.

RESULTS

The cumulative absorption rate of fibrosis-like findings in the severe and non-severe groups at T4 was 24.3% (17/70) and 52.0% (53/102), respectively. In both groups, ground-glass opacity (GGO) with consolidation showed a clear decreasing trend at T1, after which they maintained similar lower levels. The GGO in the severe group showed an increasing trend first at T1 and then decreasing at T4; however, the incidence decreased gradually in the non-severe group. Most fibrosis-like findings showed a tendency to decrease rapidly and then remained stable. Bronchial dilatation in the severe group persisted at an intermediate level.

CONCLUSIONS

After discharge, the characteristics and changing trends of pulmonary sequelae caused by COVID-19 were significantly different between the two groups. Pulmonary sequelae were more serious and recovery was slower in patients with severe/critical disease than in patients with moderate disease. A portion of the fibrosis-like findings were completely absorbed in patients with moderate and severe/critical diseases.

KEY POINTS

• Lung sequelae were more serious and recovery was slower in severe/critical COVID-19 patients. • Complete absorption of fibrosis-like findings after a short-term follow-up was observed in at least 17/70 (24.3%) of COVID-19 patients with severe/critical disease and 53/102 (52.0%) of COVID-19 patients with moderate disease. • The most common fibrosis-like findings was a parenchymal band; irregular interface was a nonspecific sign of COVID-19, and the percentage of bronchial dilatation in patients with severe/critical disease remained at a relatively stable medium level (range, 31.6 to 47.8%) at all stages.

D-Limonene Is a Potential Monoterpene to Inhibit PI3K/Akt/IKK-α/NF-κB p65 Signaling Pathway in Coronavirus Disease 2019 Pulmonary Fibrosis

At the time of the prevalence of coronavirus disease 2019 (COVID-19), pulmonary fibrosis (PF) related to COVID-19 has become the main sequela. However, the mechanism of PF related to COVID (COVID-PF) is unknown. This study aimed to explore the key targets in the development of COVID-PF and the mechanism of d-limonene in the COVID-PF treatment. The differentially expressed genes of COVID-PF were downloaded from the GeneCards database, and their pathways were analyzed. d-Limonene was molecularly docked with related proteins to screen its pharmacological targets, and a rat lung fibrosis model was established to verify d-limonene's effect on COVID-PF-related targets. The results showed that the imbalance between collagen breakdown and metabolism, inflammatory response, and angiogenesis are the core processes of COVID-PF; and PI3K/AKT signaling pathways are the key targets of the treatment of COVID-PF. The ability of d-limonene to protect against PF induced by bleomycin in rats was reported. The mechanism is related to the binding of PI3K and NF-κB p65, and the inhibition of PI3K/Akt/IKK-α/NF-κB p65 signaling pathway expression and phosphorylation. These results confirmed the relationship between the PI3K–Akt signaling pathway and COVID-PF, showing that d-limonene has a potential therapeutic value for COVID-PF.

Life after recovery from SARS, influenza, and Middle East respiratory syndrome: An insight into possible long-term consequences of COVID-19

Viral infectious diseases have become an increased public health issue in the past 20 years. The outbreaks of severe acute respiratory syndrome coronavirus (SARS-CoV-1) in 2002, influenza H1N1 in 2009, Middle East respiratory syndrome-CoV in 2012, and the current new coronavirus SARS-CoV-2 have shown that viral infectious diseases are a major concern in the 21^st century. As the world lives under the pandemic of a new coronavirus (COVID-19), knowing the clinical characteristics from those past diseases and their long-term outcomes is important to understand the current coronavirus pandemic and its complications and consequences better and plan for possible future outbreaks. Several long-term complications have been described with these respiratory viral diseases, such as decreased pulmonary function, pulmonary fibrosis, chronic fatigue syndrome, avascular necrosis of bone, polyneuropathy, encephalitis, posttraumatic stress disorder, depression, and anxiety. This article summarizes several studies describing chronic complications and long-term outcomes of patients recovered from these viral syndromes.

COVID-19: What Should the General Practitioner Know?

BACKGROUND

SARS-CoV-2 infection is currently the most significant public health challenge. Its presentation ranges from mild to severe respiratory failure and septic shock. Rapid transmission of the virus is dangerous with a high possibility of life-threatening complications. Lack of treatment standards for SARS-CoV-2 is responsible for the current dilemma in clinical medicine.

METHODS

An electronic literature search was done using PubMed to gather information on the pathogenesis, transmission of infection, clinical symptoms, diagnosis, and therapeutic options for COVID-19. Search items included "SARS-CoV-2", "COVID-19" and "coronavirus infection".

RESULTS

In light of the current global crisis caused by SARS-CoV-2, the exchange of information within the scientific community should be quick and extremely transparent. Thus, this review presents the available information necessary for a general practitioner. Such presentation of data should allow the reader quick access to basic and crucial information related to epidemiology, viral transmission, clinical symptoms, diagnostics, treatment, and complications that may occur in the course of COVID-19.

CONCLUSION

Rapidly increasing amounts of information about the diagnosis and treatment of patients with SARS-CoV-2 allow a better understanding of the etiology and course of the infection. In the current epidemiological situation, readily accessible information helps minimize the time to acquire knowledge and focus on prevention methods, diagnostic and treatment options. Thus, this review highlights key issues related to SARS-CoV-2 infection and contains the most useful data for daily medical practice.

Serial computed tomography findings of Coronavirus disease 2019 (COVID-19) pneumonia treated with favipiravir and steroid therapy: report of 11 cases

BACKGROUND

This study evaluated the time course of computed tomography (CT) findings of patients with COVID-19 pneumonia who required mechanical ventilation and were treated with favipiravir and steroid therapy.

RESULTS

Eleven patients with severe COVID-19 pneumonia were included. CT findings assessed at the three time points showed that all patients had ground-glass opacities (GGO) and consolidation and mixed pattern at intubation. Consolidation and mixed pattern disappeared in most of the patients whereas GGO persisted in all patients at 1-month follow-up. In addition to GGO, a subpleural line and bronchus distortion and bronchial dilatation were frequent findings. The degree of resolution of GGO varied depending on each patient. The GGO score correlated significantly with the time from symptoms onset to initiation of steroid therapy (ρ = 0.707, p = 0.015).

CONCLUSIONS

At 1-month follow-up after discharge, non-GGO lesions were absorbed almost completely, and GGO were a predominant CT manifestation. Starting steroid therapy earlier after onset of symptoms in severe COVID-19 pneumonia may reduce the extent of GGO at 1-month follow-up.

Findings of Serial Computed Tomography Imaging in Patients with Coronavirus Disease-19

AIM: We investigated the serial changes of chest computed tomography (CT) in patients with coronavirus disease-2019 (COVID-19) presenting with viral-induced lung damage on follow-up CT. METHODS: We evaluated 66 patients with confirmed COVID-19, who had undergone at least two chest CTs from February 24 to April 21, 2020. Nine patients also had a third CT. All patients demonstrated viral-induced lung damage (organizing pneumonia-like pattern) on second CT. The involvement pattern of each lobe and the extent of infiltration (based on CT score) were assessed on serial CTs to determine changes throughout the disease course. Patients’ demographic and clinical data and final outcome were also recorded. RESULTS: Mean age (standard deviation [SD]) of patients was 56.04 (15.2) years old; 51.5% were male. About 93.9% of patients had survived. Mean (SD) interval between the first and second CT and second and third CT was 7.6 (5.9) and 16.8 (8.3) days, respectively. The extent of total lung involvement was significantly higher in the second CT compared with the first CT (p < 0.001) and also increased non-significantly in the third CT (p = 0.29). The right lower lobe persistently had the highest CT score through the disease course. CONCLUSION: Evaluation of serial CT imaging can reveal information regarding the stage of COVID-19, thus providing help for appropriate treatment planning.

Repurposing of histone deacetylase inhibitors: A promising strategy to combat pulmonary fibrosis promoted by TGF-β signalling in COVID-19 survivors

Coronavirus disease 2019 (COVID-19) has rapidly spread around the world causing global public health emergency. In the last twenty years, we have witnessed several viral epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV), Influenza A virus subtype H1N1 and most recently Middle East respiratory syndrome coronavirus (MERS-CoV). There were tremendous efforts endeavoured globally by scientists to combat these viral diseases and now for SARS-CoV-2. Several drugs such as chloroquine, arbidol, remdesivir, favipiravir and dexamethasone are adopted for use against COVID-19 and currently clinical studies are underway to test their safety and efficacy for treating COVID-19 patients. As per World Health Organization reports, so far more than 16 million people are affected by COVID-19 with a recovery of close to 10 million and deaths at 600,000 globally.

SARS-CoV-2 infection is reported to cause extensive pulmonary damages in affected people. Given the large number of recoveries, it is important to follow-up the recovered patients for apparent lung function abnormalities. In this review, we discuss our understanding about the development of long-term pulmonary abnormalities such as lung fibrosis observed in patients recovered from coronavirus infections (SARS-CoV and MERS-CoV) and probable epigenetic therapeutic strategy to prevent the development of similar pulmonary abnormalities in SARS-CoV-2 recovered patients. In this regard, we address the use of U.S. Food and Drug Administration (FDA) approved histone deacetylase (HDAC) inhibitors therapy to manage pulmonary fibrosis and their underlying molecular mechanisms in managing the pathologic processes in COVID-19 recovered patients.

COVID-19: A review of what radiologists need to know

Coronavirus disease-2019 (COVID-19) is spreading throughout the world. Chest radiography and computed tomography play an important role in disease diagnosis, differential diagnosis, severity evaluation, prognosis prediction, therapeutic effects assessment and follow-up of patients with COVID-19. In this review, we summarize knowledge of COVID-19 pneumonia that may help improve the abilities of radiologists to diagnose and evaluate this highly infectious disease, which is essential for epidemic control and preventing new outbreaks in the short term.

Long-Term Respiratory and Neurological Sequelae of COVID-19

Since the initial reports of coronavirus disease 2019 (COVID-19) in China in late 2019, infections from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have spread rapidly, resulting in a global pandemic that has caused millions of deaths. Initially, the large number of infected people required the direction of global healthcare resources to provide supportive care for the acutely ill population in an attempt to reduce mortality. While clinical trials for safe and effective antiviral agents are ongoing, and vaccine development programs are being accelerated, long-term sequelae of SARS-CoV-2 infection have become increasingly recognized and concerning. Although the upper and lower respiratory tracts are the main sites of entry of SARS-CoV-2 into the body, resulting in COVID-19 pneumonia as the most common presentation, acute lung damage may be followed by pulmonary fibrosis and chronic impairment of lung function, with impaired quality of life. Also, increasing reports have shown that SARS-CoV-2 infection involves the central nervous system (CNS) and the peripheral nervous system (PNS) and directly or indirectly damages neurons, leading to long-term neurological sequelae. This review aims to provide an update on the mechanisms involved in the development of the long-term sequelae of SARS-CoV-2 infection in the 3 main areas of lung injury, neuronal injury, and neurodegenerative diseases, including Alzheimer disease, Parkinson disease, and multiple sclerosis, and highlights the need for patient monitoring following the acute stage of infection with SARS-CoV-2 to provide a rationale for the prevention, diagnosis, and management of these potential long-term sequelae.

Residual clinical damage after COVID-19: A retrospective and prospective observational cohort study

Data on residual clinical damage after Coronavirus disease-2019 (COVID-19) are lacking. The aims of this study were to investigate whether COVID-19 leaves behind residual dysfunction, and identify patients who might benefit from post-discharge monitoring. All patients aged ≥18 years admitted to the Emergency Department (ED) for COVID-19, and evaluated at post-discharge follow-up between 7 April and 7 May, 2020, were enrolled. Primary outcome was need of follow-up, defined as the presence at follow-up of at least one among: respiratory rate (RR) >20 breaths/min, uncontrolled blood pressure (BP) requiring therapeutic change, moderate to very severe dyspnoea, malnutrition, or new-onset cognitive impairment, according to validated scores. Post-traumatic stress disorder (PTSD) served as secondary outcome. 185 patients were included. Median [interquartile range] time from hospital discharge to follow-up was 23 [20-29] days. 109 (58.9%) patients needed follow-up. At follow-up evaluation, 58 (31.3%) patients were dyspnoeic, 41 (22.2%) tachypnoeic, 10 (5.4%) malnourished, 106 (57.3%) at risk for malnutrition. Forty (21.6%) patients had uncontrolled BP requiring therapeutic change, and 47 (25.4%) new-onset cognitive impairment. PTSD was observed in 41 (22.2%) patients. At regression tree analysis, the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2) and body mass index (BMI) at ED presentation, and age emerged as independent predictors of the need of follow-up. Patients with PaO2/FiO2 <324 and BMI ≥33 Kg/m2 had the highest odds to require follow-up. Among hospitalised patients, age ≥63 years, or age <63 plus non-invasive ventilation or diabetes identified those with the highest probability to need follow-up. PTSD was independently predicted by female gender and hospitalisation, the latter being protective (odds ratio, OR, 4.03, 95% confidence interval, CI, 1.76 to 9.47, p 0.0011; OR 0.37, 95% CI 0.14 to 0.92, p 0.033, respectively). COVID-19 leaves behind physical and psychological dysfunctions. Follow-up programmes should be implemented for selected patients.

Applying the WHO ICF Framework to the Outcome Measures Used in the Evaluation of Long-Term Clinical Outcomes in Coronavirus Outbreaks

(1) Objective: The World Health Organization’s (WHO) International Classification of Functioning, Disability and Health (ICF) classification is a unified framework for the description of health and health-related states. This study aimed to use the ICF framework to classify outcome measures used in follow-up studies of coronavirus outbreaks and make recommendations for future studies. (2) Methods: EMBASE, MEDLINE, CINAHL and PsycINFO were systematically searched for original studies assessing clinical outcomes in adult survivors of severe acute respiratory distress syndrome (SARS), middle east respiratory syndrome (MERS) and coronavirus disease-19 (COVID-19) after hospital discharge. Individual items of the identified outcome measures were linked to ICF second-level and third-level categories using ICF linking rules and categorized according to an ICF component. (3) Results: In total, 33 outcome measures were identified from 36 studies. Commonly used (a) ICF body function measures were Pulmonary Function Tests (PFT), Impact of event scale (IES-R) and Hospital Anxiety and Depression Scale (HADS); (b) ICF activity was 6-Minute Walking Distance (6MWD); (c) ICF participation measures included Short Form-36 (SF-36) and St George’s Respiratory Questionnaire (SGRQ). ICF environmental factors and personal factors were rarely measured. (4) Conclusions: We recommend future COVID-19 follow-up studies to use the ICF framework to select a combination of outcome measures that capture all the components for a better understanding of the impact on survivors and planning interventions to maximize functional return.

Evolution of chest CT manifestations of COVID-19: a longitudinal study

Background

The aim of this study was to investigate the chest CT manifestations of COVID-19 and its CT evolving process to explore its inherent outcomes.

Methods

Inpatients diagnosed with COVID-19 at the Enze Hospital from January 17, 2020 to February 15, 2020 were included. The evolving characteristics of CT manifestations and treatment outcomes were analyzed.

Results

Twenty-two patients with COVID-19 were included in the study. Clinical symptoms at the time of onset included fever (n=19) and cough (n=8). The first CT findings mainly included ground-glass opacities (GGOs) (n=18), lung consolidation (n=7), interlobular septal thickening (n=5), and fibrosis-like stripes (n=4). Dynamic CT showed GGOs, lung consolidation, and fibrosis-like stripes, all of which demonstrated a trend that initially increased in number, and then gradually decreased in number or disappeared. According to the characteristics of CT evolution. COVID-19 could be divided into early stage, progressing stage, recovery stage, and dissipation stage. The median times of the respective stages were: early stage—3 days (1–8 days) after disease onset, progressing stage—7 days (4–17 days) after onset, recovery stage—10 days (8–14 days) after onset, and dissipation stage—19.5 days (11–25 days) after onset.

Conclusions

COVID-19 has an acute onset, with main imaging manifestations of different types of GGO with or without lung consolidation in the subpleural regions of the bilateral lungs. The CT manifestations of lung lesions change rapidly. The lung lesions of mild and ordinary types of COVID-19 may improve significantly or disappear in a short period after active treatment, with good prognosis. Moreover, fibrosis-like stripes may be a sign of atelectasis of sub-segment lung tissue of COVID-19 and may be a specific sign for the diagnosis of COVID-19.

Postdischarge symptoms and rehabilitation needs in survivors of COVID-19 infection: A cross-sectional evaluation

BACKGROUND

There is currently very limited information on the nature and prevalence of post-COVID-19 symptoms after hospital discharge.

METHODS

A purposive sample of 100 survivors discharged from a large University hospital were assessed 4 to 8 weeks after discharge by a multidisciplinary team of rehabilitation professionals using a specialist telephone screening tool designed to capture symptoms and impact on daily life. EQ-5D-5L telephone version was also completed.

RESULTS

Participants were between 29 and 71 days (mean 48 days) postdischarge from hospital. Thirty-two participants required treatment in intensive care unit (ICU group) and 68 were managed in hospital wards without needing ICU care (ward group). New illness-related fatigue was the most common reported symptom by 72% participants in ICU group and 60.3% in ward group. The next most common symptoms were breathlessness (65.6% in ICU group and 42.6% in ward group) and psychological distress (46.9% in ICU group and 23.5% in ward group). There was a clinically significant drop in EQ5D in 68.8% in ICU group and in 45.6% in ward group.

CONCLUSIONS

This is the first study from the United Kingdom reporting on postdischarge symptoms. We recommend planning rehabilitation services to manage these symptoms appropriately and maximize the functional return of COVID-19 survivors.

Pneumothorax in patients with prior or current COVID-19 pneumonia

As the number of COVID-19 cases emerge, new complications associated with the disease are recognized. We present three cases of spontaneous pneumothorax in patients with COVID-19. They show that a pneumothorax can occur during different phases of disease, in patients without a pulmonary disease history and is not necessarily associated to positive pressure ventilation or severity of COVID-19. Although the exact causative mechanisms remain unknown, this observation might imply that extensive alveolar destruction due to COVID-19 may lead to bulla formation resulting in subsequent pneumothorax.

Post-COVID-19 follow-up clinic: depicting chronicity of a new disease

BACKGROUND AND AIM OF THE WORK

The coronavirus disease-19 (COVID-19) outbreak is posing considerable challenges to healthcare systems and societies worldwide. While the knowledge on the acute phase of the disease has rapidly expanded, little is known on the consequences of COVID-19 following clinical remission. We set up a multidisciplinary COVID-19 follow-up outpatient clinic to identify and address the clinical needs of COVID-19 survivors. Here we describe the features of our follow-up programme.

METHODS

The multidisciplinary assessment comprises a complete physical examination, respiratory evaluation (peripheral oxygen saturation, respiratory rate, dyspnoea assessment, lung ultrasound and pulmonary function), cardiovascular assessment (electrocardiography, echocardiography), nutritional assessment (anthropometrics, mini Nutritional Assessment screening tool), neurological examination including cognitive tests, and mental health assessment. All data are prospectively collected, and blood is sampled for biobanking.

RESULTS

Since 7 April to 5 June, 2020, 453 out of the 1388 COVID-19 survivors managed at our University Hospital have been evaluated at the Outpatient COVID-19 Follow-up Clinic. The characteristics of the follow-up cohort are similar to those of the whole cohort of COVID-19 in terms of demographics, comorbidities, and COVID-19 severity upon ED presentation, indicating that the follow-up cohort is representative of the whole cohort.

CONCLUSIONS

Continuous patient monitoring might give an answer to the numerous unsolved questions about what comes next in this pandemic and beyond. This will help physicians and researchers establish strategies to face future pandemics and develop preventative and therapeutic strategies for similar hyperinflammatory conditions.

Could Ergothioneine Aid in the Treatment of Coronavirus Patients?

Infection with SARS-CoV-2 causes the coronavirus infectious disease 2019 (COVID-19), a pandemic that has, at present, infected more than 11 million people globally. Some COVID-19 patients develop a severe and critical illness, spurred on by excessive inflammation that can lead to respiratory or multiorgan failure. Numerous studies have established the unique array of cytoprotective properties of the dietary amino acid ergothioneine. Based on studies in a range of in vitro and in vivo models, ergothioneine has exhibited the ability to modulate inflammation, scavenge free radicals, protect against acute respiratory distress syndrome, prevent endothelial dysfunction, protect against ischemia and reperfusion injury, protect against neuronal damage, counteract iron dysregulation, hinder lung and liver fibrosis, and mitigate damage to the lungs, kidneys, liver, gastrointestinal tract, and testis, amongst many others. When compiled, this evidence suggests that ergothioneine has a potential application in the treatment of the underlying pathology of COVID-19. We propose that ergothioneine could be used as a therapeutic to reduce the severity and mortality of COVID-19, especially in the elderly and those with underlying health conditions. This review presents evidence to support that proposal.

The pulmonary sequalae in discharged patients with COVID-19: a short-term observational study

BACKGROUND

A cluster of patients with coronavirus disease 2019 (COVID-19) pneumonia were discharged from hospitals in Wuhan, China. We aimed to determine the cumulative percentage of complete radiological resolution at each time point, to explore the relevant affecting factors, and to describe the chest CT findings at different time points after hospital discharge.

METHODS

Patients with COVID-19 pneumonia confirmed by RT-PCR who were discharged consecutively from the hospital between 5 February 2020 and 10 March 2020 and who underwent serial chest CT scans on schedule were enrolled. The radiological characteristics of all patients were collected and analysed. The total CT score was the sum of non-GGO involvement determined at discharge. Afterwards, all patients underwent chest CT scans during the 1st, 2nd, and 3rd weeks after discharge. Imaging features and distributions were analysed across different time points.

RESULTS

A total of 149 patients who completed all CT scans were evaluated; there were 67 (45.0%) men and 82 (55.0%) women, with a median age of 43 years old (IQR 36-56). The cumulative percentage of complete radiological resolution was 8.1% (12 patients), 41.6% (62), 50.3% (75), and 53.0% (79) at discharge and during the 1st, 2nd, and 3rd weeks after discharge, respectively. Patients ≤44 years old showed a significantly higher cumulative percentage of complete radiological resolution than patients > 44 years old at the 3-week follow-up. The predominant patterns of abnormalities observed at discharge were ground-glass opacity (GGO) (125 [83.9%]), fibrous stripe (81 [54.4%]), and thickening of the adjacent pleura (33 [22.1%]). The positive count of GGO, fibrous stripe and thickening of the adjacent pleura gradually decreased, while GGO and fibrous stripe showed obvious resolution during the first week and the third week after discharge, respectively. "Tinted" sign and bronchovascular bundle distortion as two special features were discovered during the evolution.

CONCLUSION

Lung lesions in COVID-19 pneumonia patients can be absorbed completely during short-term follow-up with no sequelae. Two weeks after discharge might be the optimal time point for early radiological estimation.

Vital role of chest CT in diagnosis of coronavirus disease 2019 (COVID-19)

In December 2019, a new virus called coronavirus disease 2019 (COVID-19) causing severe acute respiratory syndrome emerged in Wuhan, China, and rapidly spread to other areas of China and other regions of the world. Since it was a discovery, COVID-19 has spread to several countries and to this date, affecting about 2,329,651 people and caused about 160,721 deaths. Since most COVID-19 infected cases were diagnosed with pneumonia and characteristic chest computed tomography (CT) scan patterns, radiological examinations have become an important tool in early diagnosis. Nowadays, CT findings combined with normal blood cells (WBCs), lymphopenia and a history of epidemiological exposure have been used as criteria for clinical diagnosis of COVID-19. It is noteworthy that reverse transcription polymerase chain reaction (RT-PCR) test is still gold standard for the diagnosis. This review focuses on role of chest CT in the clinical evaluation of disease progression and more accurate diagnosis.

Long-term bone and lung consequences associated with hospital-acquired severe acute respiratory syndrome: a 15-year follow-up from a prospective cohort study

The most severe sequelae after rehabilitation from SARS are femoral head necrosis and pulmonary fibrosis. We performed a 15-year follow-up on the lung and bone conditions of SARS patients. We evaluated the recovery from lung damage and femoral head necrosis in an observational cohort study of SARS patients using pulmonary CT scans, hip joint MRI examinations, pulmonary function tests and hip joint function questionnaires. Eighty medical staff contracted SARS in 2003. Two patients died of SARS, and 78 were enrolled in this study from August 2003 to March 2018. Seventy-one patients completed the 15-year follow-up. The percentage of pulmonary lesions on CT scans diminished from 2003 (9.40 ± 7.83)% to 2004 (3.20 ± 4.78)% (P < 0.001) and remained stable thereafter until 2018 (4.60 ± 6.37)%. Between 2006 and 2018, the proportion of patients with interstitial changes who had improved pulmonary function was lower than that of patients without lesions, as demonstrated by the one-second ratio (FEV₁/FVC%, t = 2.21, P = 0.04) and mid-flow of maximum expiration (FEF_25%–75%, t = 2.76, P = 0.01). The volume of femoral head necrosis decreased significantly from 2003 (38.83 ± 21.01)% to 2005 (30.38 ± 20.23)% (P = 0.000 2), then declined slowly from 2005 to 2013 (28.99 ± 20.59)% and plateaued until 2018 (25.52 ± 15.51)%. Pulmonary interstitial damage and functional decline caused by SARS mostly recovered, with a greater extent of recovery within 2 years after rehabilitation. Femoral head necrosis induced by large doses of steroid pulse therapy in SARS patients was not progressive and was partially reversible.

Imaging of Emerging Infectious Diseases

Purpose of Review

Emerging infectious diseases have seen a record increase in prevalence, and understanding their management is critical in an increasingly global community. In this paper, we review current literature detailing the role of radiology in the diagnosis and treatment of the Ebola (EVD), Zika (ZVD), Chikungunya (CHIKF), H1N1, Middle East Respiratory (MERS), and Severe Acute Respiratory Syndrome (SARS) viruses.

Recent Findings

Complex protocols are required to safely use portable imaging in EVD to prevent nosocomial spread of disease. In ZVD, antenatal ultrasound can detect fetal abnormalities early, allowing implementation of care and support to affected families. Imaging is useful in assessing the extent of involvement of chronic CHIKF and monitoring treatment effect. Chest radiography and CT play a more direct role in the diagnosis and monitoring of the viral infections with primarily respiratory manifestations (H1N1, MERS, and SARS).

Summary

Radiology plays a variable role in emerging infectious diseases, requiring an understanding of disease transmission and safe imaging practices, as well as imaging features that affect clinical management.

Correlation between Pneumonia Severity and Pulmonary Complications in Middle East Respiratory Syndrome

This nationwide, prospective cohort study evaluated pulmonary function and radiological sequelae according to infection severity in 73 survivors from the 2015 Middle East respiratory syndrome (MERS) outbreak in Korea. Patients with severe pneumonia in MERS-coronavirus infection had more impaired pulmonary function than those with no or mild pneumonia at the 1-year follow-up, which was compatible with the radiological sequelae. Severe pneumonia significantly impairs pulmonary function and makes long radiological sequelae in MERS.

Overactive Epidermal Growth Factor Receptor Signaling Leads to Increased Fibrosis after Severe Acute Respiratory Syndrome Coronavirus Infection

Severe acute respiratory syndrome coronavirus (SARS-CoV) is a highly pathogenic respiratory virus that causes morbidity and mortality in humans. After infection with SARS-CoV, the acute lung injury caused by the virus must be repaired to regain lung function. A dysregulation in this wound healing process leads to fibrosis. Many survivors of SARS-CoV infection develop pulmonary fibrosis (PF), with higher prevalence in older patients. Using mouse models of SARS-CoV pathogenesis, we have identified that the wound repair pathway, controlled by the epidermal growth factor receptor (EGFR), is critical to recovery from SARS-CoV-induced tissue damage. In mice with constitutively active EGFR [EGFR(DSK5) mice], we find that SARS-CoV infection causes enhanced lung disease. Importantly, we show that during infection, the EGFR ligands amphiregulin and heparin-binding EGF-like growth factor (HB-EGF) are upregulated, and exogenous addition of these ligands during infection leads to enhanced lung disease and altered wound healing dynamics. Our data demonstrate a key role of EGFR in the host response to SARS-CoV and how it may be implicated in lung disease induced by other highly pathogenic respiratory viruses.IMPORTANCE PF has many causative triggers, including severe respiratory viruses such as SARS-CoV. Currently there are no treatments to prevent the onset or limit the progression of PF, and the molecular pathways underlying the development of PF are not well understood. In this study, we identified a role for the balanced control of EGFR signaling as a key factor in progression to PF. These data demonstrate that therapeutic treatment modulating EGFR activation could protect against PF development caused by severe respiratory virus infection.

The role of epidermal growth factor receptor (EGFR) signaling in SARS coronavirus-induced pulmonary fibrosis

Many survivors of the 2003 outbreak of severe acute respiratory syndrome (SARS) developed residual pulmonary fibrosis with increased severity seen in older patients. Autopsies of patients that died from SARS also showed fibrosis to varying extents. Pulmonary fibrosis can be occasionally seen as a consequence to several respiratory viral infections but is much more common after a SARS coronavirus (SARS-CoV) infection. Given the threat of future outbreaks of severe coronavirus disease, including Middle East respiratory syndrome (MERS), it is important to understand the mechanisms responsible for pulmonary fibrosis, so as to support the development of therapeutic countermeasures and mitigate sequelae of infection. In this article, we summarize pulmonary fibrotic changes observed after a SARS-CoV infection, discuss the extent to which other respiratory viruses induce fibrosis, describe available animal models to study the development of SARS-CoV induced fibrosis and review evidence that pulmonary fibrosis is caused by a hyperactive host response to lung injury mediated by epidermal growth factor receptor (EGFR) signaling. We summarize work from our group and others indicating that inhibiting EGFR signaling may prevent an excessive fibrotic response to SARS-CoV and other respiratory viral infections and propose directions for future research.

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Patients who survived SARS coronavirus infection often developed pulmonary fibrosis.

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Mouse models of SARS-CoV infection recapitulate fibrotic lesions seen in humans.

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Epidermal growth factor receptor (EGFR) may modulate the wound healing response to SARS-CoV.

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The EGFR pathway is a prime target for therapeutic interventions to reduce fibrosis after respiratory virus infection.