Changes in structural lung disease in cystic fibrosis children over 4 years as evaluated by high-resolution computed tomography

Evolution of Lung Disease Studied by Computed Tomography in Adults with Cystic Fibrosis Treated with Elexacaftor/Tezacaftor/Ivacaftor

Elexacaftor-tezacaftor-ivacaftor (ETI) has shown clinical and spirometric benefits in cystic fibrosis (CF). CT remains a vital tool for diagnosing and monitoring structural lung disease. This study aimed to assess the evolution of lung disease, as evaluated through CT, in adults with CF after at least one year of ETI treatment. This ambispective observational analysis assessed lung CT scans performed before initiating ETI and after at least one year of treatment, using the modified Bhalla scoring system. For those patients with an earlier CT scan, a pre-treatment phase analysis was performed. Epidemiological, clinical, and functional parameters were evaluated. Results: Sixty-two patients were included (35 males, median age 30.4 ± 7.87 years). After at least one year of ETI, significant improvements were observed in the global CT Bhalla score (12.2 ± 2.8 vs. 14.0 ± 2.8), peribronchial thickening (1.4 ± 0.6 vs. 1.0 ± 0.4), and mucus plugging (1.6 ± 0.7 vs. 0.8 ± 0.6) (p < 0.001). Spirometry parameters increased significantly: the percentage of the predicted forced expiratory volume in the first second (ppFEV1) increased from 66.5 ± 19.8 to 77.0 ± 20.4 (p = 0.005) and forced vital capacity (ppFVC) from 80.6 ± 16.4 to 91.6 ± 14.1 (p < 0.001). Additionally, body mass index showed a significant increase. A moderate correlation was found between the Bhalla score and spirometry results. In the pre-treatment phase (n = 52), mucus plugging demonstrated a significant worsening, whereas global CT score, other subscores, and spirometry did not change significantly. Conclusions: In adults with CF, after at least one year of ETI, a significant improvement in structural lung disease was achieved, as reflected by the CT Bhalla score.

Association Between Lung Parenchymal Attenuation in Computed Tomography and Airflow Limitation in Adults with Cystic Fibrosis

Objectives: To determine the association between airflow limitation and the quantification of lung attenuation in computed tomography (CT) in adult patients with cystic fibrosis (CF). Methods: A cross-sectional study in a single center between January 2013 and December 2018 in adult patients with stable CF. We collected clinical data and the results of spirometry and plethysmography. A chest CT at inspiration and expiration, using a specific software that automatically measured the lung attenuation, was performed. Results: In total, 73 patients (63% males) were included. The mean age was 31.6 ± 12.3 years and the FEV1 was 67.8 ± 25.9% pred. An airflow limitation was found in 63%, the mean residual volume was 159.9% pred, and air trapping was observed in 50 (87.7%) of the patients. The patients with airflow limitations showed a higher bulla index and a percentage of lung voxels in the range of emphysema. The FEV1 and the FEV1/FVC correlated with the percentage of the lungs at a high attenuation value (HAV), the range of emphysema, and the bulla index at inspiration, as well as the mean lung density at expiration and the inspiratory-expiratory variation of the mean lung density (MLDi-e). Finally, in the multivariate model, the MLDi-e and the HAV at inspiration were associated with airflow limitations. Conclusions: The measurements obtained from the automated quantification of lung parenchymal attenuation predicts airflow limitation in CF.

Pathological remodeling of distal lung matrix in end-stage cystic fibrosis patients

BACKGROUND

Manifestations of cystic fibrosis, although well-characterized in the proximal airways, are understudied in the distal lung. Characterization of the cystic fibrosis lung 'matrisome' (matrix proteome) has not been previously described, and could help identify biomarkers and inform therapeutic strategies.

METHODS

We performed liquid chromatography-mass spectrometry, gene ontology analysis, and multi-modal imaging, including histology, immunofluorescence, and electron microscopy for a comprehensive evaluation of distal human lung extracellular matrix (matrix) structure and composition in end-stage cystic fibrosis.

RESULTS

Quantitative proteomic profiling identified sixty-eight (68) matrix constituents with significantly altered expression in end-stage cystic fibrosis. Over 90% of significantly different matrix peptides detected, including structural and basement membrane proteins, were expressed at lower levels in cystic fibrosis. However, the total abundance of matrix in cystic fibrosis lungs was not significantly different from control lungs, suggesting that cystic fibrosis leads to loss of diversity among lung matrix proteins rather than an absolute loss of matrix. Visualization of distal lung matrix via immunofluorescence and electron microscopy revealed pathological remodeling of distal lung tissue architecture and loss of alveolar basement membrane, consistent with significantly altered pathways identified by gene ontology analysis.

CONCLUSIONS

Dysregulation of matrix organization and aberrant wound healing pathways are associated with loss of matrix protein diversity and obliteration of distal lung tissue structure in end-stage cystic fibrosis. While many therapeutics aim to functionally restore defective cystic fibrosis transmembrane conductance regulator (CFTR), drugs that target dysregulated matrix pathways may serve as adjunct interventions to support lung recovery.

Predictive value of computed tomography scoring systems evolution in adults with cystic fibrosis

OBJECTIVES

To assess whether the evolution of two consecutive high-resolution computed tomography (HRCT) scores in patients with cystic fibrosis (CF) has prognostic value.

METHODS

A longitudinal retrospective study was performed to research adult patients with CF. Two consecutive HRCT studies were scored using Bhalla and Brody II scoring scales by two senior radiologists. Annual scoring changes for each scale were calculated and correlated with annual FEV1% decline, with pulmonary exacerbations and number of antibiotic treatments.

RESULTS

We selected sixty-four adult patients. The median interval between the two HRCTs was 3.88 ± 1.59 years. The mean spirometric values showed dynamic lung volumes lower than the general population; globally, there was a worsening of respiratory function over time. The change in the annual HRCT scores was positive on both scales, indicating a worse structural situation over time. The Brody II scale annual change showed a significant statistical correlation with a decline in the annual FEV1%, exacerbations and number of oral antibiotic treatments. In contrast, for the Bhalla scale, the relationship was moderately inverse with exacerbations and with the number of oral treatments. No statistically significant relationships were found for the change in the annual FEV1% and exacerbations or number of antibiotic treatments. The interobservational and intraobservational agreements were very strong in both scales.

CONCLUSIONS

The annual evolution of the Brody II HRCT scoring system demonstrated a predictive value and correlated with FEV1% decline, pulmonary exacerbations and oral antibiotic treatments.

KEY POINTS

• HRCT evolution has prognostic value in cystic fibrosis. • Temporal evolution for the Brody II score is useful for clinical follow-up. • Brody II score changes correlate with FEV1% decline, pulmonary exacerbations and number of antibiotic treatments.

Evaluation of high resolution computed tomography findings of cystic fibrosis

BACKGROUND/AIMS

Morphological changes due to lung disease in patients with cystic fibrosis (CF) were evaluated using high resolution computed tomography (HRCT), and the HRCT scores obtained using the Bhalla scoring system were correlated with those obtained using clinical and laboratory indicators.

METHODS

Medical records of 28 children with CF who underwent chest CT in Department of Pediatric Allergy and Immunology, Cukurova University Balcali Hospital between March 2011 and January 2016 were retrospectively reviewed. Demographic data and physical examination, respiratory cultures, pulmonary function tests, and chest HRCT findings were evaluated. Patients were divided into the following two groups according to their forced expiratory volume in the first second (FEV1) values: normal FEV1 (≥ 80% of predicted values) and low FEV1 (< 80% of predicted values). Deep throat or sputum cultures were evaluated for the presence of Pseudomonas aeruginosa (PsA) and other bacteria. HRCT scans were scored using the Bhalla scoring system.

RESULTS

No significant correlation was found between the Bhalla scores and sex, age group, or height percentiles. Significant relationships were found between the Bhalla score and weight (p = 0.036) and body mass index (BMI) (p = 0.032) percentiles below the third percentile, bacterial growth in the sputum/ deep throat cultures (p = 0.009), and presence of PsA (p = 0.004). Moreover, a significant correlation was found between the Bhalla score and FEV1 (r = -0.315, p = 0.0272), forced vital capacity (FVC; r = -0.381, p = 0.0178), forced expiratory flow between 25% and 75% of FVC (r = -0.229, p = 0.0431), and BMI (r = -3.368, p = 0.050).

CONCLUSION

Chest HRCT is an important diagnostic tool for the pulmonary evaluation of children with CF.

High-resolution computed tomography findings in young infants with cystic fibrosis detected by newborn screening

OBJECTIVE

High-resolution computed tomography (HRCT) allows the early detection of pathological changes in the lung structure, and reproducible scoring systems can be used to quantify chest computed tomography (CT) findings in patients with cystic fibrosis (CF). The aim of the study was to describe early HRCT findings according to a validated scoring system in infants with CF diagnosed by newborn screening (NBS).

METHODS

This cross-sectional study included infants with CF diagnosed by NBS who were born between January 2013 and January 2017 and who underwent HRCT scanning within the first year after diagnosis when they were clinically stable. The CT scans were evaluated using the modified Bhalla score.

RESULTS

Thirty-two subjects underwent HRCT scanning. The mean total-modified Bhalla score was 3.6±2.1, and 93.8% of the scans were abnormal. Pseudomonas aeruginosa airway colonization was associated with increased modified Bhalla score values. Bronchial wall thickening was the most common feature (90.6%), followed by bronchial collapse/consolidation (59.4%), mosaic attenuation/perfusion (50%), bronchiectasis (37.5%) and mucus plugging (15.6%). Bronchial wall thickening was diffuse in most of the patients.

CONCLUSION

A substantial proportion of infants diagnosed with CF after detection by NBS already showed evidence of lung disease. P. aeruginosa colonization was associated with increased Bhalla scores, highlighting the importance of this CF pathogen in early structural lung disease. The presence of bronchial wall thickening at such a young age may reflect the presence of airway inflammatory processes. The detection and quantification of structural abnormalities with the modified Bhalla score may aid in the identification of lung disease before it is clinically apparent.

A semiquantitative MRI-Score can predict loss of lung function in patients with cystic fibrosis: Preliminary results

OBJECTIVES

To evaluate the applicability of a semiquantitative MRI scoring system (MR-CF-S) as a prognostic marker for clinical course of cystic fibrosis (CF) lung disease.

METHODS

This observational study of a single-centre CF cohort included a group of 61 patients (mean age 12.9 ± 4.7 years) receiving morphological and functional pulmonary MRI, pulmonary function testing (PFT) and follow-up of 2 years. MRI was analysed by three raters using MR-CF-S. The inter-rater agreement, correlation of score categories with forced expiratory volume in 1 s (FEV₁) at baseline, and the predictive value of clinical parameters, and score categories was assessed for the whole cohort and a subgroup of 40 patients with moderately impaired lung function.

RESULTS

The inter-rater agreement of MR-CF-S was sufficient (mean intraclass correlation coefficient 0.92). MR-CF-S (-0.62; p < 0.05) and most of the categories significantly correlated with FEV₁. Differences between patients with relevant loss of FEV₁ (>3%/year) and normal course were only significant for MR-CF-S (p < 0.05) but not for clinical parameters. Centrilobular opacity (CO) was the most promising score category for prediction of a decline of FEV₁ (area under curve: whole cohort 0.69; subgroup 0.86).

CONCLUSIONS

MR-CF-S is promising to predict a loss of lung function. CO seems to be a particular finding in CF patients with an abnormal course.

KEY POINTS

• Lung imaging is essential in the diagnostic work-up of CF patients • MRI serves as a powerful, radiation-free modality in paediatric CF patients • Observational single-centre study showed significant correlation of MR-CF score and FEV ₁ • MR-CF score is promising in predicting a loss of lung function.

Diagnosis and early life risk factors for bronchiectasis in cystic fibrosis: a review

INTRODUCTION

Lung disease in cystic fibrosis begins in early life with neutrophil-dominated inflammation and infection, is progressive and results in structural lung damage characterised by bronchial dilation and bronchiectasis. Preventative strategies must be employed in early life but require a better understanding of how bronchiectasis develops.

AREAS COVERED

In this review we have addressed the diagnosis and early life risk factors for bronchiectasis in young children with cystic fibrosis. A systematic review was not performed and the literature reviewed was known to the authors. Expert commentary: Bronchiectasis represents a process of progressive dilatation and damage of airway walls and is traditionally considered to be irreversible. Diagnosis is primarily by detecting a bronchial:arterial ratio of >1 on chest CT scan. Lung volume has a greater influence on airway diameter than on arterial making control of lung volume during scanning critical. Early life risk factors for the onset and progression bronchiectasis include: severe cystic fibrosis genotype; neutrophilic inflammation with free neutrophil elastase activity in the lung; and pulmonary infection. Bronchiectasis develops in the majority of children before they reach school age despite the best current therapy. To prevent bronchiectasis novel therapies are going to have to be given to infants.