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

Authors:

Abstract

Background SARS is not only an acute disease, but also leads to long-term impaired lung diffusing capacity in some survivors. However, there is a paucity of data regarding long-term CT findings in survivors after SARS. The aim of this study was to assess the changes in lung function and lung thin-section computed tomography (CT) features in patients recovering from severe acute respiratory syndrome (SARS), especially the dynamic changes in ground-glass opacity (GGO). Material/Methods Clinical and radiological data from 11 patients with SARS were collected. The serial follow-up thin-section CTs were evaluated at 3, 6, and 84 months after SARS presentation. The distribution and predominant thin-section CT findings of lesions were evaluated. Results The extent of the lesions on the CT scans of the 11 patients decreased at 6 and 84 months compared to 3 months. The number of segments involved on 84-month follow-up CTs was less than those at 6 months (P<0.05). The predominant thin-section CT manifestation at 84 months (intralobular and interlobular septal thickening) was different than that at 6 months, at which GGO was predominant. Conclusions During convalescence after SARS, GGO and intralobular and interlobular septal thickening were the main thin-section CT manifestation. Intralobular and interlobular septal thickening predominated over GGO at 84 months.
Received: 2015.12.04
Accepted: 2016.01.12
Published: 2016.08.08
2367 2 3 31
Thin-Section Computed Tomography
Manifestations During Convalescence and Long-
Term Follow-Up of Patients with Severe Acute
Respiratory Syndrome (SARS)
ABC 1 Xiaohua Wu
CD 2 Dawei Dong
DE 1 Daqing Ma
Corresponding Author: Daqing Ma, e-mail: cjr.madaqing@vip.163.com
Source of support: Departmental sources
Background: SARS is not only an acute disease, but also leads to long-term impaired lung diffusing capacity in some survi-
vors. However, there is a paucity of data regarding long-term CT findings in survivors after SARS. The aim of
this study was to assess the changes in lung function and lung thin-section computed tomography (CT) fea-
tures in patients recovering from severe acute respiratory syndrome (SARS), especially the dynamic changes in
ground-glass opacity (GGO).
Material/Methods: Clinical and radiological data from 11 patients with SARS were collected. The serial follow-up thin-section CTs
were evaluated at 3, 6, and 84 months after SARS presentation. The distribution and predominant thin-sec-
tion CT findings of lesions were evaluated.
Results: The extent of the lesions on the CT scans of the 11 patients decreased at 6 and 84 months compared to 3
months. The number of segments involved on 84-month follow-up CTs was less than those at 6 months (P<0.05).
The predominant thin-section CT manifestation at 84 months (intralobular and interlobular septal thickening)
was different than that at 6 months, at which GGO was predominant.
Conclusions: During convalescence after SARS, GGO and intralobular and interlobular septal thickening were the main thin-
section CT manifestation. Intralobular and interlobular septal thickening predominated over GGO at 84 months.
MeSH Keywords: Pneumonia, Viral • Severe Acute Respiratory Syndrome • Tomography Scanners, X-Ray Computed
Full-text PDF: http://www.medscimonit.com/abstract/index/idArt/896985
Authors’ Contribution:
Study Design A
Data Collection B
Statistical Analysis C
Data Interpretation D
Manuscript Preparation E
Literature Search F
Funds Collection G
1 Department of Radiology, Beijng Friendship Hospital, Capital Medical University,
Beijing, P.R. China
2 Department of Radiology, Beijng Xiaotangshan Hospital, Beijing, P.R. China
e-ISSN 1643-3750
© Med Sci Monit, 2016; 22: 2793-2799
DOI: 10.12659/MSM.896985
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Background
Severe acute respiratory syndrome (SARS) is an emergent
infectious disease that was epidemic in 2002 and 2003 [1].
Between November 2002 and July 2003, an outbreak of SARS
in southern China infected about 8000 people and led to 774
recorded deaths, mostly in Hong Kong [1]. Within weeks, SARS
spread from Hong Kong to 37 countries [2]. A novel corona-
virus (SARS-CoV) is responsible for SARS. The coronavirus re-
sponsible for Middle East Respiratory Syndrome (MERS-CoV)
is similar to SARS-CoV. A better understanding of the features
of SARS-CoV would help to guide control measures and treat-
ment for similar diseases, such as MERS-CoV [3,4].
Lung injury caused by SARS-CoV is one of the main clinical
manifestations and directly affects prognosis. Imaging plays
an important role in the diagnosis and evaluation of patients
with SARS. Thin-section computed tomography (CT) can show
pulmonary abnormalities in patients with normal findings on
plain X-ray and is useful in depicting the patterns and extent
of the abnormalities [5–8]. During the acute phase of SARS,
the more distinctive radiographic features include the pre-
dominant involvement of lung periphery and lower zone, and
the absence of cavitation, hilar lymphadenopathy, and pleu-
ral effusion [9,10]. Radiographic progression from unilateral
focal lesion to either multifocal or bilateral involvement dur-
ing the second phase of the disease, followed by radiographic
improvement with treatment, are commonly observed [9,10].
SARS is not only an acute disease, but also leads to long-
term impaired lung diffusing capacity in about 24% of sur-
vivors [11], resulting in significantly lower exercise tolerance
compared with the age-matched general population [11–13].
Another study suggested that the lung function impairment
might not be related to the disease itself, but rather to extra-
pulmonary muscle weakness [14]. Nevertheless, 75% of SARS
survivors still show lung abnormalities on thin-section CT 5
years after their illness onset [14].
However, there is a paucity of data regarding long-term CT find-
ings in survivors after SARS. Therefore, the aim of the pres-
ent study was to assess the changes in lung function and lung
thin-section CT features in patients recovering from SARS, es-
pecially the dynamic changes in ground-glass opacity (GGO).
Material and Methods
Patients
Eleven patients who had been discharged after treatment
for SARS as inpatients between February and June 2003 at
Beijing Friendship Hospital were followed up at 3, 6, and 84
months using thin-section CT and were included in the present
study. The diagnosis of SARS was based on the World Health
Organization criteria [15].
This study received Ethics Committee approval from Beijing
Friendship Hospital affiliated to Capital Medical University
(Approval ID: 2015-P2-076-01). The committees waived the
need for individual consent because of the retrospective na-
ture of the study.
CT scans
The CT examinations were performed with an 8-row multi
-
detector CT scanner (High Speed Ultra; GE Medical Systems,
Milwaukee, WI, USA), and a 64-row multidetector CT scanner
(LightSpeed Ultra; GE Medical Systems, Milwaukee, WI, USA)
using the following parameters: 120 kVp, 150 mA, 5-mm col-
limation, 1.35:1 pitch, and reconstruction matrix of 512×512.
The subjects were scanned in a supine position during breath-
holding at full inspiration. Thin-section CT images were re-
constructed with 0.625-mm or 1.25-mm collimation with a
high spatial frequency algorithm or standard algorithm and
then sent to the workstation (ADW 4.2; GE Medical Systems,
Milwaukee, WI, USA) for analyzing. Thin-section CT images
were evaluated using a lung window, with a window level of
–600 HU and window width of 1500 HU. The soft-tissue win-
dow was not evaluated.
Image interpretation
All thin-section CT images were reviewed by 2 radiologists. The
radiologists were aware of the diagnosis of SARS. For all scans,
the radiologists were blinded to the names of the patients and
the length of time since onset, but they were aware of which
images belonged to the same patient. A consensus had to be
reached between the 2 radiologists about the abnormalities.
Discrepancies were solved by discussion.
The radiologists determined the extent of the following thin-
section CT abnormalities: ground-glass opacity, consolidation,
reticular pattern, patchy decreased attenuation, and subpleu-
ral line, in accordance with the standard morphologic descrip-
tors based on the Fleischner Society Nomenclature Committee
recommendations [16] and other studies [17,18]. The evalua-
tion of the extent of lung involvement was based on the seg-
ments of the lung anatomy: 10 segments in the right lung and
10 segments in the left lung (2 segments were considered in
the apicoposterius segment left upper lobe and 2 segments
were considered in the inferior front segment of the left low-
er lobe). The following rules were used to evaluate the lobe
involvement: if more than half of the segment on the biggest
scope of lesion level on axial thin-section CT was involved,
then the segment (1 point) was recorded as being involved;
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if no more than half of the segment was involved, then 0.5
point was recorded.
To evaluate the distribution of the lesion, it was also classi-
fied into 3 categories: 1) subpleural and/or peribronchovascu-
lar, 2) diffuse, or 3) irregular. In addition, each CT was divided
into 3 categories: 1) anterior, 2) posterior, or 3) anterior and
posterior. Finally, for every CT scan, the radiologists were re-
quired to generalize the main CT manifestation: 1) GGO pre-
dominant, or 2) fine reticulation predominant.
Pulmonary function test (PFT)
The PFT of the patients was classified into mild, moderate, or
serious. We evaluated lung volumes (total lung capacity [TLC],
vital capacity [VC], residual volume [RV], functional residual
capacity [FRC] using the nitrogen washout method), spirometry
(forced vital capacity [FVC], forced expiratory volume in 1 sec-
ond [FEV1], FEV1/FVC ratio), and surface area for gas exchange
(diffusion capacity adjusted for hemoglobin [DLCO]). The DLCO
was determined using the single-breath carbon monoxide tech-
nique and an infrared analyzer. FEV1/expected% of <30%, 30–
50%, 50–80%, and >80% were regarded as extremely serious,
serious, moderate, and mild, respectively. DLCO values <80%
of predicted were regarded as being impaired.
Statistical analysis
Descriptive statistics are presented. Continuous data are pre-
sented as means ± standard deviation (SD). Categorical data
are presented as frequencies. SPSS 16.0 (IBM, Armonk, NY,
USA) was used for statistical analysis.
Case
number Gender Age at
onset
3 months 6 months 84 months
Predominant
HRCT findings
Segments
involved
Predominant
HRCT findings
Segments
involved
Predominant
HRCT findings
Segments
involved PFT
1 F 30 GGO 15
Reticulation
and
interlobular
thickening
15
Reticulation
and interlobular
thickening
15 Mild
2 M 35 GGO 3 GGO 2 GGO 1 Mild
3 M 54
Consolidation
and GGO 8 GGO 6
Reticulation
and interlobular
thickening
4 N
4 F 38 Diffuse GGO 9 GGO 3
Reticulation
and interlobular
thickening
3 Mild
5 F 42
Consolidation
and GGO 13
Reticulation
and
interlobular
thickening
7
Reticulation
and interlobular
thickening
5 Mild
6 F 32 GGO 14
Reticulation
and interlobular
thickening
11.5 Mild
7 M 31 GGO 18
Reticulation
and interlobular
thickening
9.5 Mild
8 F 31
Reticulation
and
interlobular
thickening
5
Reticulation
and interlobular
thickening
3.5 Mild
9 F 40 GGO 9
Reticulation
and interlobular
thickening
6.5
Moderate
10 F 48 GGO 18 GGO 16 Mild
11 F 36 GGO 9 Normal 0 N
Table 1. Characteristics of the patients.
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Results
Characteristics of the patients
Eleven patients (8 females and 3 males; age range: 30–54 years,
mean age: 38.6 years) met the selection criteria. Table 1 pres-
ents the demographic data and changes in lung function and
lung radiographic features of the 11 patients during follow-
up. All of the 11 patients were healthy before developing SARS
and none were smokers. In acute phase, glucocorticoid was
used in all 11 patients (methylprednisolone; the biggest dose
was 840 mg/d, mean duration 9.5 days, and after improving
for 2 or 3 days, methylprednisolone dose was decreased). All
patients were still alive during the study period. Twenty-seven
CT scans were evaluated. At 84 months, 5 patients were still
experiencing persistent dyspnea, 4 had cough, 2 had sputum
production, and 2 experienced all 3 symptoms. The mean time
from discharge to the first follow-up was 3 months (range, 2
to 4 months).
Thin-section CT findings
Table 2 presents the thin-section CT findings. All 11 patients
underwent CT scans at 6- and 84-month follow-up. Multiple
lobes or segments were involved in all 11 cases. Among them,
48 segments (average of 10 segments per patient) were in-
volved at 3 months, 106 segments (average of 9.6 per case)
were involved at 6 months, and 75 segments (average of
6.8 per case) were involved at 84 months. At 3 months, as
the predominant thin-section CT feature, 2 patients (40.0%)
showed GGO (Figure 1) and 3 showed consolidation and GGO
(60.0%) (Figure 2). At 6 months, as the predominant thin-sec-
tion CT feature, 3 patients (27.3%) showed reticulation and
interlobular thickening (Figure 3) and 8 (72.7%) showed GGO.
At 84 months, as the predominant thin-section CT feature, 1
patient (9.1%) had no lung abnormality, 8 patients (72.7%)
showed reticulation and interlobular thickening, and 2 (18.2%)
showed GGO. Traction bronchiectasis was found in 3 patients
(Figure 3), while patchy decreased attenuation was found in 1
patient (Figure 1). Traction bronchiectasis was found at 6- and
84-month thin-section CT, and patchy decreased attenuation
was found at 3-, 6-, and 84-month thin-section CT.
Pulmonary function test
The PFT results of the 11 patients at 84 months are present-
ed in Table 1. Two patients (18%) had a normal PFT. Nine pa-
tients (81.8%) had a low DLCO. Eight patients (72.7%) had
mild lung function damage, and 1 (9.1%) had moderate lung
function damage.
Trends in changes in predominant thin-section CT findings
over time
Table 2 shows that the predominant CT findings in SARS sur-
vivors shift from a predominance of the GGO feature at 3
(100.0%) and 6 (72.7%) months to the predominance of re-
ticulation and interlobular thickening at 84 months (72.7%).
Figuress 1–3 present typical thin-section CT imaging at 3, 6,
and 84 months, respectively.
CT findings 3 months (n=5) 6 months (n=11) 84 months (n=11)
GGO 5 (100.0%) 11 (100.0%) 10 (90.9%)
Consolidation 5 (100.0%) 0 0
Reticulation 5 (100.0%) 9 (81.7%) 10 (90.9%)
Subpleural line 1 (20.0%) 1 (9.1%) 1 (9.1%)
Traction brochiectasis 0 2 (18.2%) 2 (18.2%)
Air trapping 1 (20.0%) 1 (9.1%) 1 (9.1%)
Small nodule 2 (40.0%) 2 (18.2%) 2 (9.1%)
GGO predominance 5 (100.0%) 2 (18.2%)
Reticulation predominance 0 3 (27.3%) 8 (72.7%)
Distribution of peripheral 3 (60.0%) 9 (81.7%) 9 (81.7%)
Distribution on axial section (anterior and
posterior) 5 (100.0%) 11 (100.0%) 10 (90.9%)
Segments involved 48 (48/500) 106 (106/2200) 75 (75/2200)
Table 2. CT findings during follow-up.
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Discussion
During viral lung infections, the lungs histologically show dif-
fuse alveolar damage, including interstitial lymphocyte infil-
tration, air-space hemorrhage, edema, fibrosis, type 2 cell hy-
perplasia, and hyaline tissue formation [19]. Diffuse alveolar
damage is found in some kinds of viral pneumonia, but it is
usually self-limited and radiologic abnormalities usually di-
minish within 3 weeks in immunocompetent patients [20].
In SARS-CoV-infected patients, intralobular and interlobular
septal thickening, subpleural lines, and traction bronchiecta-
sis were observed as late as 84 months after SARS infection
in the present study. All these thin-section CT manifestations
were also found at 3 and 6 months during the recovery phase
A B C
Figure 1. Case 1, SARS survivor, female, 30 years old. (A) The CT scan at 3 months showed diffuse bilateral GGO (arrow). (B) Six
months later, GGO was reduced. (C) At 84 months, GGO was greatly reduced and fine reticulation (intralobular and
interlobular septal thickening) predominated (arrow). Patchy decreased attenuation was seen at 3-, 6-, and 84-month CT
(triangle).
A B C
Figure 2. Case 7, SARS survivor, male, 31 years old. (A) Chest radiography showed consolidation in the lower lobes of both lungs in
acute phase. (B) Six months later, GGO (triangle) and reticulation (arrow) were observed in both lungs. (C) Fine reticulation
(arrow) still persisted but GGO could not be found at 84-month CT.
A B C
Figure 3. Case 6, SARS survivor, female, 32 years old. (A) X-ray radiography showed a large consolidation in the lower lobes of both
lungs in acute phase. (B) Six months later, X-ray revealed GGO, septal thickening, and fine-mesh shadows (white arrow).
Traction bronchiectasis was found in the left lower lobe. (C) At 84 months, GGO was reduced and interlobular thickening
predominated. Traction bronchiectasis was still present.
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of SARS, which may indicate lung fibrosis, as observed in pre-
vious studies [21,22]. To the best of our knowledge, the pres-
ent study is the first to report abnormal imaging at up to 7
years after SARS-CoV pneumonia.
The characteristic thin-section CT finding in SARS survivors
changed from GGO predominance at 3–6 months to fine re-
ticulation (intralobular and interlobular septal thickening)
predominance at 7 years. GGO was found in 8 patients at 6
months and in 2 patients at 84 months. Some studies report-
ed the imaging features of the recovery phase in patients with
SARS [21,22]. Antonio et al. [21] analyzed the thin-section CT
findings at an average of 36.5 days in 24 patients and observed
that the main findings in the recovery phase were GGO, intra-
lobular and interlobular septal thickening, traction bronchi-
ectasis, and subpleural lines. They also reported that fibrosis
began early and tended to be found in elderly and more seri-
ously affected patients. However, in the present study, all 11
patients showed abnormalities that may indicate fibrosis at 6
months, and 10 patients still had signs of lung fibrosis after
7 years. All patients were 30–54 years old when they were in-
fected by SARS-CoV; therefore, lung fibrosis could be a long-
term sequela of SARS-CoV infection.
Importantly, the thin-section CT lung abnormalities observed in
the present study seemed to be different from those induced
by other pneumonia viruses [23,24]. It is known that many
SARS patients suffer from ARDS/DAD in the acute phase [25].
Nevertheless, the present study suggests that either the lung
fibrosis is very slow to disappear after infection or that the CT
abnormality is different from lung fibrosis induced by other
pneumonia viruses. However, the results of the present study
do not resolve this issue. With regard to the physical impair-
ment that may accompany the abnormalities on thin-section
CT, some previous studies suggest that the physical impair-
ment after SARS persists for at least 12 months [11,13], while
another study suggests only mild impairments at 5 years [14].
A study has shown that the immune response after SARS per-
sists for at least 90 days [26], but no data is available to deter-
mine exactly how long it persists and whether it could involve
lungs as a long-term sequela. In our study, mild or moderate
pulmonary function damage was still present in 81.8% of the
patients at 7 years after SARS infection.
Some studies have shown that after the acute phase of ARDS,
CT findings are variable [26–28]. In ARDS, although complete
resolution of abnormalities may occur, the typical CT findings
at the later stage are that of a coarse reticular pattern and GGO
in the anterior part of the lungs [25,27,29]. In this setting, it
is likely that GGO represents areas of fine fibrosis, which are
observed on thin-section CT. Our study shows that the CT ab-
normalities of all patients had a diffuse distribution, which was
similar that reported in a recent study by Masclans et al. [30].
Indeed, Masclans et al. [30] found that 76% of patients had
abnormalities on high-resolution CT at 6 months after infec-
tion, and these abnormalities were typically areas of reticula-
tion and GGO. Therefore, the distribution of thin-section abnor-
malities in our study seem to be different from those reported
in some other studies [25,27,29] on late-stage ARDS. However,
drawing conclusions is impossible because of the lack of ac-
companying histopathological examination in most patients
with SARS and ARDS.
Another finding of the present study is the presence of trac-
tion bronchiectasis, which represents airway abnormalities, as
well as patchy decreased attenuation, which probably repre-
sents airway abnormalities. Traction bronchiectasis was found
in 3 patients, while patchy decreased attenuation was found in
1 patient. Similar results in SARS patients were also reported
in some other studies [24,31]. Masclans et al. [30] found that
airway disease was more common in ARDS survivors, again
suggesting the possibility of the presence of underlying lung
fibrosis in these survivors of SARS.
The present study is not without limitations. This was a retro-
spective review of patients evaluated at 2 centers, with all of
the issues of selection and observational biases that this de-
sign entails. Secondly, the sample size was smaller than that
of prior studies and may not represent most patients. Thirdly,
the pulmonary function test results at 3 and 6 months were
unavailable in most patients.
Conclusions
This study of 11 SARS patients found that lung abnormalities
on thin-section CT still existed in SARS survivors 7 years af-
ter infection, though the extent became less. During convales-
cence after SARS, GGO and intralobular and interlobular sep-
tal thickening were the main thin-section CT manifestations.
From 6 months to 7 years after SARS, the predominant thin-
section CT findings changed from GGO predominance to fine
reticulation predominance, which probably represents the in-
terstitial fibrotic proliferation recovery phase of diffuse alveo-
lar damage. These abnormalities were consistent with the PFT.
Conflict of interest
The authors declare that they have no actual or potential con-
flicts of interest.
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... They found that fibrotic changes at HRCT imaging occurred more frequently in COVID-19 survivors (70%) than in the non-COVID group (43%, p-value < 0.001). Interestingly, fibrotic lesions were associated with ICU length of stay, and patients surviving pneumonia-ARDS frequently showed impairments in physical, emotional, and cognitive health [41]. Our data revealed an inverse relationship between the presence of lung lesions and the duration of the follow-up, suggesting a progressive nature of the healing process. ...
... Intriguingly, Wu et al. systematically gathered clinical and radiological data from 11 patients diagnosed with severe acute respiratory syndrome (SARS) during the 2003 outbreak, conducting serial follow-up thin-section CT scans at 3, 6, and 84 months. Notably, the extent of the lesions observed in the CT scans demonstrated a reduction at both 6 and 84 months when compared to the initial assessment at 3 months [41]. ...
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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.
... 1 Sequels after the SARS-CoV-2 infection, especially dyspnea, fatigue, and mental health issues, are becoming an important burden to societies, healthcare systems, and the economy in India. 2 The consequences of previous coronavirus infections are not well understood, and it is unclear if they may be reproduced in SARS-CoV-2-infected patients. Along with pulmonary function, 3,4 COVID- 19 can have an impact on one's renal, 5 cardiovascular, neuropsychiatric, 6 and nutritional health. 7 Up to 12 months following the infection, recovered patients may experience persistent COVID-19 symptoms. ...
... 28 A recent study showed that fibrous stripes, observed in 51.2% of convalescent patients with COVID-19, are the most predominant radiological abnormality 1 year after discharge. 29 Additionally, a long-term follow-up iScience Article of 11 convalescent patients with severe acute respiratory syndrome (SARS) showed that lung fibrosis manifestations, such as interlobular or intralobular thickening and subpleural lines, were observed 7 years after infection, 30 suggesting that early fibrous stripe lesions may require long-term follow-up. Our study might provide indications for medical interventions for pulmonary long COVID. ...
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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.
... Some studies reported reductions in DLCO scores ranging from 11% to 45% among patients after one year, while the 6MWT results improved (38). Wu et al. showed radiological abnormalities resembling pulmonary fibrosis seven years after SARS (39). The results of studies on SARS patients, in whom the consequences of damage to pulmonary function are visible seven years after onset of the disease, point to the importance of a timely PR programme in post-COVID-19 patients. ...
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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.
... The literature does not extensively document extrapulmonary radiographic symptoms of SARS, but SARS-CoV isolates have been discovered in the intestine, spleen, liver, lymph nodes, and kidneys during autopsies [53]. Reports indicate that osteonecrosis and reduced bone density have been seen in SARS patients who were administered high-dose corticosteroids [54]. Just as patients suspected of having MERS infection, it is crucial to isolate the patient afflicted with SARS in order to avoid transmission inside the hospital. ...
... Most of the fibrotic-like changes in COVID-19 patients would disappear up to 1 year post hospital discharge [21][22][23] . It has been reported that in survivors of the preceding SARS pandemic, fibrotic-like changes present at 6 months may still improve at 84 months of follow-up, such as traction bronchiectasis 24 . Actually, periods of fibroproliferation of variable severity are part of the natural history of diffuse alveolar damage 25,26 . ...
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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.
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Aims: Although several research have been undertaken to investigate the impact of the vaccination on long Coronavirus Disease 2019 (COVID-19) syndrome or post-acute sequelae, there is a lack of published evidence on the long-term effects of vaccines on lung-sequelae-related disease. Considering the limited global COVID-19 vaccine distribution, it is essential to establish the impact of vaccination in reducing pulmonary complications. Turkey has been offering COVID-19 vaccines from two platforms, including BNT162b2 (Pfizer-BioNTech, mRNA vaccine) and CoronaVac (Sinovac, inactivated vaccine). This study aimed to evaluate the efficacy of BioNTech and Sinovac vaccines in reducing post-COVID-19 pulmonary complications in individuals. Methods: A total of 94 patients COVID-19 pneumonia patients who were categorized based on the quantity of BioNTech or Sinovac vaccines they received before their first COVID-19 infection were included. The inclusion criteria consisted of a confirmed diagnosis of COVID-19 pneumonia through polymerase chain reaction testing, availability of the mentioned before and follow-up computed tomography scans, and administration of at least one dose of vaccine. Results: The number of complications in patients fully vaccinated with Sinovac and who experienced post-COVID lung complications was significantly greater than in those vaccinated with BioNTech. The C-reactive protein and D-Dimer measurements of individuals who experienced complications in the Sinovac vaccinated group were significantly elevated on the index date. Conclusion: The quantity of lung sequelae after COVID and laboratory parameters indicating this result were found to be higher in inactivated virus vaccines than in mRNA vaccines. This suggests that the protection of inactivated vaccines may be insufficient in severe cases.
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Acute lung injury usually causes hypoxaemic respiratory failure and acute respiratory distress syndrome CARDS). Although diffuse alveolar damage is the hallmark of ARDS, other histopathological patterns of injury, such as acute and fibrinoid organising pneumonia, can be associated with acute respiratory failure. Acute eosinophilic pneumonia can also cause acute hypoxaemic respiratory failure and mimic ARDS. This pictorial essay reviews the high-resolution CT findings of acute lung injury and the correlative histopathological findings.
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With increased globalisation comes the likelihood that infectious disease appearing in one country will spread rapidly to another, severe acute respiratory syndrome (SARS) being a recent example. However, although SARS infected some 10,000 individuals, killing around 1000, it did not lead to the devastating health impact that many feared, but a rather disproportionate economic impact. The disproportionate scale and nature of this impact has caused concern that outbreaks of more serious disease could cause catastrophic impacts on the global economy. Understanding factors that led to the impact of SARS might help to deal with the possible impact and management of such other infectious disease outbreaks. In this respect, the role of risk-its perception, communication and management-is critical. This paper looks at the role that risk, and especially the perception of risk, its communication and management, played in driving the economic impact of SARS. It considers the public and public health response to SARS, the role of the media and official organisations, and proposes policy and research priorities for establishing a system to better deal with the next global infectious disease outbreak. It is concluded that the potential for the rapid spread of infectious disease is not necessarily a greater threat than it has always been, but the effect that an outbreak can have on the economy is, which requires further research and policy development.
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This review compares the clinical features, laboratory aspects and treatment options of severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS). Bats are the natural reservoirs of SARS-like coronaviruses (CoVs) and are likely the reservoir of MERS coronavirus (MERS-CoV). Although a small number of camels have been found to have positive nasal swabs by real-time polymerase chain reaction and to carry antibody against MERS-CoV, the transmission route and the intermediary animal source remain uncertain amongst the sporadic primary cases. Both SARS-CoV and MERS-CoV may cause severe respiratory failure and extrapulmonary features such as diarrhoea, whereas mild or asymptomatic cases also occur in both conditions. In comparison with SARS, patients with MERS are older with male predominance, more comorbid illness and relatively lower human-to-human transmission potential. Although the viral kinetics of MERS-CoV remain unknown, nosocomial infections of MERS occur early within the first week of illness of the index case, whereas those of SARS occurred mainly in the second week of illness when the patient's upper airway viral load peaks on day 10 of illness. In-vitro data suggest that interferon (IFN) with or without ribavirin and mycophenolic acid may inhibit MERS-CoV, whereas protease inhibitors and IFN have inhibitory activity against SARS-CoV. Although there are some similarities in the clinical features, MERS progresses to respiratory failure much more rapidly than SARS. The higher case fatality rate of MERS is likely related to older age and comorbid illness. More studies are needed to understand MERS-CoV in order to guide public health infection control measures and treatment.
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Objective Few studies have systematically evaluated high-resolution CT (HRCT) imaging of the thorax 5 years after severe ARDS to determine the association between radiologic findings and functional disability. The primary aim of this study was to determine chest radiologic abnormalities at 5 years in survivors of severe ARDS from the University of Toronto ARDS cohort. The secondary aim was to determine the relationship between the observed radiologic abnormalities on HRCT scan and pulmonary symptoms, pulmonary function test abnormalities, and health-related quality of life at 5-year follow-up. Methods HRCT scans were obtained in 24 of 64 eligible patients. Three anatomically comparable levels were selected for scoring, and each level was divided into four quadrants. The extent and distribution of individual CT image patterns (ground glass opacification, intense parenchymal opacification, reticular pattern, and decreased attenuation) were also reported. Results Eighteen patients (75%) had abnormal findings on HRCT imaging. These findings were minor and in the nondependent lung zones. No correlation was found between radiologic findings and patient symptoms, pulmonary function tests, 6-min walk distances, or heath-related quality of life measures. Conclusions Exercise and functional limitations experienced by survivors of severe ARDS are unlikely to be related to structural lung disease and may be more consistent with extrapulmonary muscle weakness.
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Chest radiography and computed tomography (CT) have a crucial role to play in the diagnosis and management of acute respiratory distress syndrome (ARDS). The identification of pulmonary opacification is a requirement for the definition of ARDS on the chest radiograph, while CT has a role to play, not only in the diagnosis of ARDS, but also in the identification of complications. This paper reviews the radiological appearances of ARDS that have been documented for some time, and also more recent research that has identified a role for CT in directing ventilation and in prognostication.
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ARDS can produce a loss of lung function with persistent sequelae. This study aimed to evaluate health-related quality of life (HRQL) in survivors of ARDS compared with a healthy reference population and to determine the middle/long-term radiographic abnormalities and functional status, as well as their relation to observed HRQL, in these patients. This was a prospective study carried out in three ICUs. HRQL in patients was determined with the Nottingham Health Profile immediately after ARDS diagnosis and 6 months after diagnosis. Patients underwent complete respiratory function testing, chest CT scan study, and the 6-min walk test. Follow-up was conducted in 38 patients with ARDS. Survivors of ARDS presented a poorer overall HRQL vs the general population, mainly because of lower scores in the dimensions related to mobility, energy, and social isolation. Limitations in daily life activities were documented in 40%. Respiratory function was altered in 67%, with a restrictive respiratory pattern in 58%. Radiologic study disclosed alterations in 76% (mainly reticular pattern). Patients were able to cover only 366 m (318-411 m) in the 6-min walk test and had a minimum pulse oximetry of 93% (90%-94%). A significant correlation was documented between the overall quality of life at first and at 6 months (r = 0.68, P < .01). Survivors of ARDS after 6 months had a poorer HRQL than the healthy population and showed mild radiographic and functional involvement. Early HRQL study in these patients enabled early detection of those who would present more long-term HRQL morbidity.