Automatic quantitative computed tomography measurement of longitudinal lung volume loss in interstitial lung diseases

Objectives To compare the lung CT volume (CTvol) and pulmonary function tests in an interstitial lung disease (ILD) population. Then to evaluate the CTvol loss between idiopathic pulmonary fibrosis (IPF) and non-IPF and explore a prognostic value of annual CTvol loss in IPF. Methods We conducted in an expert center a retrospective study between 2005 and 2018 on consecutive patients with ILD. CTvol was measured automatically using commercial software based on a deep learning algorithm. In the first group, Spearman correlation coefficients (r) between forced vital capacity (FVC), total lung capacity (TLC), and CTvol were calculated. In a second group, annual CTvol loss was calculated using linear regression analysis and compared with the Mann–Whitney test. In a last group of IPF patients, annual CTvol loss was calculated between baseline and 1-year CTs for investigating with the Youden index a prognostic value of major adverse event at 3 years. Univariate and log-rank tests were calculated. Results In total, 560 patients (4610 CTs) were analyzed. For 1171 CTs, CTvol was correlated with FVC (r: 0.86) and TLC (r: 0.84) (p < 0.0001). In 408 patients (3332 CT), median annual CTvol loss was 155.7 mL in IPF versus 50.7 mL in non-IPF (p < 0.0001) over 5.03 years. In 73 IPF patients, a relative annual CTvol loss of 7.9% was associated with major adverse events (log-rank, p < 0.0001) in univariate analysis (p < 0.001). Conclusions Automated lung CT volume may be an alternative or a complementary biomarker to pulmonary function tests for the assessment of lung volume loss in ILD. Key Points • There is a good correlation between lung CT volume and forced vital capacity, as well as for with total lung capacity measurements (r of 0.86 and 0.84 respectively, p < 0.0001). • Median annual CT volume loss is significantly higher in patients with idiopathic pulmonary fibrosis than in patients with other fibrotic interstitial lung diseases (155.7 versus 50.7 mL, p < 0.0001). • In idiopathic pulmonary fibrosis, a relative annual CT volume loss higher than 9.4% is associated with a significantly reduced mean survival time at 2.0 years versus 2.8 years (log-rank, p < 0.0001).

Lung Ultrasound as a First-Line Test in the Evaluation of Post-COVID-19 Pulmonary Sequelae

Background: Interstitial lung sequelae are increasingly being reported in survivors of COVID-19 pneumonia. An early detection of these lesions may help prevent the development of irreversible lung fibrosis. Lung ultrasound (LUS) has shown high diagnostic accuracy in interstitial lung disease (ILD) and could likely be used as a first-line test for post-COVID-19 lung sequelae.Methods: Single-center observational prospective study. Follow-up assessments of consecutive patients hospitalized for COVID-19 pneumonia were conducted 2–5 months after the hospitalization. All patients underwent pulmonary function tests (PFTs), high-resolution computed tomography (HRCT), and LUS. Radiological alterations in HRCT were quantified using the Warrick score. The LUS score was obtained by evaluating the presence of pathological B-lines in 12 thoracic areas (range, 0–12). The correlation between the LUS and Warrick scores was analyzed.Results: Three hundred and fifty-two patients who recovered from COVID-19 pneumonia were recruited between July and September 2020. At follow-up, dyspnea was the most frequent symptom (69.3%). FVC and DLCO alterations were present in 79 (22.4%) and 234 (66.5%) patients, respectively. HRCT showed relevant interstitial lung sequelae (RILS) in 154 (43.8%) patients (Warrick score ≥ 7). The LUS score was strongly correlated with the HRCT Warrick score (r = 0.77) and showed a moderate inverse correlation with DLCO (r = −0.55). The ROC curve analysis revealed that a LUS score ≥ 3 indicated an excellent ability to discriminate patients with RILS (sensitivity, 94.2%; specificity, 81.8%; negative predictive value, 94.7%).Conclusions: LUS could be implemented as a first-line procedure in the evaluation of Post-COVID-19 interstitial lung sequelae. A normal LUS examination rules out the presence of these sequelae in COVID-19 survivors, avoiding the need for additional diagnostic tests such as HRCT.

A study of correlation of pulmonary function test in patients with metabolic syndrome with different components of metabolic syndrome

Background: The increasing incidence of metabolic syndrome has been on the rise especially in urban population and leading to increased risk of cardiovascular disease (CVD) and diabetes mellitus. It has been associated with impairment of pulmonary functions. However, there is limited data regarding the association with individual components of metabolic syndrome and overall effect on components of pulmonary functions.Methods: This is a cross sectional study consisting of 50 subjects with metabolic syndrome. All the subjects underwent pulmonary function tests and the association between different components of metabolic syndrome and pulmonary function were examined using unpaired t-test and Pearson’s partial correlation coefficient. This data was analysed by using statistical package for the social sciences (SPSS) version 12.0.Results: In females, moderate negative significant correlation was seen between forced vital capacity (FVC) and systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood sugar (FBS), triglyceride (TG), waist circumference (WC) and body mass index (BMI) whereas positive weak non-significant correlation was seen between FVC and high density lipoprotein cholesterol (HDLC), while no such relation was found with forced expiratory volume in one second (FEV1). In males, negative, moderate significant correlation was seen between FVC and FBS whereas strong, positive, significant correlation was seen between FVC and WC; between FVC and BMI. Negative, moderate, significant correlation was seen between FEV1 and WC; between FEV1 and BMI.Conclusions: Our study concluded that there was a significant impact of FBS and WC on decreasing FVC on both genders with minimally significant impact of other components of metabolic syndrome on FVC with no effect on FEV1 hence indicating a restrictive pattern of pulmonary function derangement. Hence, further studies with larger sample size is needed to confirm whether there are direct or indirect mechanisms through which insulin resistance could affect pulmonary function.

Interstitial lung disease is not rare in immune-mediated necrotizing myopathy with anti-signal recognition particle antibodies

Objectives The purpose was to clarify the characteristics of interstitial lung disease (ILD) in immune-mediated necrotizing myopathy (IMNM) patients with anti-signal recognition particle (SRP) antibodies. Methods Medical records of IMNM patients with anti-SRP antibodies were reviewed retrospectively. Results A total of 60 patients were identified. Twenty-seven (45.0%) patients were diagnosed with ILD based on lung imaging: nonspecific interstitial pneumonia (NSIP) in 17 patients (63.0%) and organizing pneumonia in 9 patients (33.3%). Reticulation pattern was identified in 17 patients (63.0%) whereas 10 cases (37.0%) showed ground glass opacity and patchy shadows by high-resolution computed tomography (HRCT). Pulmonary function tests (PFTs) were available in 18 patients, 6 (33.3%) and 10 (55.6%) patients were included in the mild and moderate group, respectively. The average age at the time of ILD onset was significantly older than those without ILD (48.6 ± 14.4 years vs. 41.2 ± 15.4 years, p < 0.05), and the frequency of dysphagia in the ILD group was higher than the group without ILD (p < 0.05). Long-term follow-up was available on 9 patients. PFTs were stable in 8 (88.9%), and the HRCT remained stable in 6 (66.7%) patients. Conclusions ILD is not rare in IMNM patients with anti-SRP antibodies, most being characterized as mild to moderate in severity. NSIP is the principal radiologic pattern, and ILD typically remains stable following treatment.

Associations between cardiac and pulmonary involvement in patients with juvenile dermatomyositis—a cross-sectional study

This study aimed at exploring the association between detectable cardiac and pulmonary involvement in long-term juvenile dermatomyositis (JDM) and to assess if patients with cardiac and pulmonary involvement differ with regard to clinical characteristics. 57 JDM patients were examined mean 17.3 (10.5) years after disease onset; this included clinical examination, myositis specific/associated autoantibodies (immunoblot), echocardiography, pulmonary function tests and high-resolution computed tomography. Cardiac involvement was defined as diastolic and/or systolic left ventricular dysfunction and pulmonary involvement as low diffusing capacity for carbon monoxide, low total lung capacity and/or high-resolution computed tomography abnormalities. Patients were stratified into the following four groups: (i) no organ involvement, (ii) pulmonary only, (iii) cardiac only, and (iv) co-existing pulmonary and cardiac involvement. Mean age was 25.7 (12.4) years and 37% were males. One patient had coronary artery disease, seven had a history of pericarditis, seven had hypertension and three had known interstitial lung disease prior to follow-up. There was no association between cardiac (10/57;18%) and pulmonary (41/57;72%) involvement (p = 0.83). After stratifying by organ involvement, 21% of patients had no organ involvement; 61% had pulmonary involvement only; 7% had cardiac involvement only and 11% had co-existing pulmonary or cardiac involvement. Patients with co-existing pulmonary or cardiac involvement had higher disease burden than the remaining patients. Patients with either cardiac or pulmonary involvement only, differed in clinical and autoantibody characteristics. We found no increased risk of developing concomitant cardiac/pulmonary involvement in JDM. Our results shed light upon possible different underlying mechanisms behind pulmonary and cardiac involvement in JDM.

Association of body weight on pulmonary function tests in young individuals (aged 18- 40 years)- A cross-sectional study

This was a prospective cross-sectional study conducted to evaluate association of waist, hip and thigh circumferences on respiratory parameters among young healthy adults. A total of 180 volunteers of different weight categories; including underweight, normal weight, over weight and obese people were recruited by using non-probability convenient sampling technique. Non-smoker males and females (non-pregnant), aged between 18-40 years with no pulmonary and cardiac disease were included in the study. Waist circumference, mid-thigh circumference, hip circumference and respiratory parameters were measured. The results showed a significant association between waist circumference with forced vital capacity (FVC) (r = 0.188, p = 0.011), average tidal volume (VT) (r = 0.160, p = 0.032), inspiratory reserve volume (IRV) (r = 0.388,p<0.001), vital capacity (VC) (r = 0.312, p<0.001), total lung capacity (TLC) (r = 0.385, p<0.001), and functional residual capacity (FRC) (r = 0.477, p<0.01), and a negative association with forced expiratory volume in 1 second (FEV1) (r = -0.148, p = 0.048) and FEV1/FVC ratio (r = -0.246, p<0.001). Significant association was not observed between waist circumference and expiratory reserve volume (ERV) (r = 0.071, p = 0.344). In the present study, increased waist, hip, and thigh circumferences were found to be negatively associated with FEV1 and FEV1/FVC ratio. Spirometry should be performed in obese and overweight young healthy adults even if they are asymptomatic, as early preventive measures can be taken to reduce the resulting morbidity.

Incidence of COVID-19 after pulmonary function tests: a retrospective cohort study

Introduction: It has been proposed that exposure to pulmonary function tests (PFT) could be associated with a higher risk of viral transmission. The risk of the Coronavirus Disease 2019 (COVID-19) transmission after performing PFT is unknown. We aimed to assess the incidence of COVID-19 after a PFT at an academic teaching facility in Buenos Aires, Argentina. Materials and methods: We conducted a retrospective cohort study including all consecutive adult patients that performed PFT between April 1, 2020 and September 30, 2020. Patients with prior COVID-19 were excluded. We defined a 15-day time window to ascertain PFT related COVID-19. The primary outcome was ascertained by consulting a national database, which has information on all patients with nasopharyngeal swabs for SARS-CoV-2 in Argentina. Results: We included 278 patients who performed a PFT. Fifty percent were women, the mean age was 54 years (SD 18), and the main comorbidities were obesity (31%), smoking (31%), hypertension (29%), and chronic lung disease (28%). The main indication for performing PFT was anesthetic preoperative risk assessment. Swabs were collected from 27 patients (10%). Twenty-two swabs (8%) were taken according to surgical protocols; five swabs (2%) were taken due to clinical suspicion of COVID-19, with only one testing positive. The cumulative incidence of COVID-19 after PFT was 0.36% (95% CI 0.01-20%). None of the technicians developed symptomatic disease. Conclusion: Given the right setting and strict adherence to international recommendations, the SARS-CoV-2 infection after having a PFT appears to be low, which follows that these procedures can be performed safely for both patients and staff.