Management of respiratory tract exacerbations in people with cystic fibrosis: Focus on imaging

Sarcoidosis versus Granulomatous and Lymphocytic Interstitial Lung Disease in Common Variable Immunodeficiency: A Comparative Review

Sarcoidosis and Granulomatous and Lymphocytic Interstitial Lung Diseases (GLILD) are two rare entities primarily characterised by the development of Interstitial Lung Disease (ILD) in the context of systemic immune dysregulation. These two conditions partially share the immunological background and pathologic findings, with granuloma as the main common feature. In this narrative review, we performed a careful comparison between sarcoidosis and GLILD, with an overview of their main similarities and differences, starting from a clinical perspective and ending with a deeper look at the immunopathogenesis and possible target therapies. Sarcoidosis occurs in immunocompetent individuals, whereas GLILD occurs in patients affected by common variable immunodeficiency (CVID). Moreover, peculiar extrapulmonary manifestations and radiological and histological features may help distinguish the two diseases. Despite that, common pathogenetic pathways have been suggested and both these disorders can cause progressive impairment of lung function and variable systemic granulomatous and non-granulomatous complications, leading to significant morbidity, reduced quality of life, and survival. Due to the rarity of these conditions and the extreme clinical variability, there are still many open questions concerning their pathogenesis, natural history, and optimal management. However, if studied in parallel, these two entities might benefit from each other, leading to a better understanding of their pathogenesis and to more tailored treatment approaches.

The Non-Invasive Detection of Pulmonary Exacerbations in Disorders of Mucociliary Clearance with Breath Analysis: A Systematic Review

Background: Disorders of mucociliary clearance, such as cystic fibrosis (CF), primary ciliary dyskinesia (PCD) and bronchiectasis of unknown origin, are characterised by periods with increased respiratory symptoms, referred to as pulmonary exacerbations. These exacerbations are hard to predict and associated with lung function decline and the loss of quality of life. To optimise treatment and preserve lung function, there is a need for non-invasive and reliable methods of detection. Breath analysis might be such a method. Methods: We systematically reviewed the existing literature on breath analysis to detect pulmonary exacerbations in mucociliary clearance disorders. Extracted data included the study design, technique of measurement, definition of an exacerbation, identified compounds and diagnostic accuracy. Results: Out of 244 identified articles, 18 were included in the review. All studies included patients with CF and two also with PCD. Age and the definition of exacerbation differed between the studies. There were five that measured volatile organic compounds (VOCs) in exhaled breath using gas chromatography with mass spectrometry, two using an electronic nose and eleven measured organic compounds in exhaled breath condensate. Most studies showed a significant correlation between pulmonary exacerbations and one or multiple compounds, mainly hydrocarbons and cytokines, but the validation of these results in other studies was lacking. Conclusions: The detection of pulmonary exacerbations by the analysis of compounds in exhaled breath seems possible but is not near clinical application due to major differences in results, study design and the definition of an exacerbation. There is a need for larger studies, with a longitudinal design, international accepted definition of an exacerbation and validation of the results in independent cohorts.

Advanced and traditional chest MRI sequence for the clinical assessment of systemic sclerosis related interstitial lung disease, compared to CT: disease extent analysis and correlations with pulmonary function tests

BACKGROUND

MRI is a radiation-free emerging alternative to CT in systemic sclerosis related interstitial lung disease (SSc-ILD) assessment. We aimed to compare a T2 radial TSE and a PD UTE MRI sequence with CT in SSc-ILD extent evaluation and correlations with pulmonary function tests (PFT).

MATERIAL AND METHODS

29 SSc-ILD patients underwent CT, MRI and PFT. ILD extent was visually assessed. Lin's concordance correlation coefficients (CCC) and Kruskal Wallis test (p-value < 0.05) were computed for inter-method comparison. Patients were divided in limited and extended disease, defining extended ILD with two methods: (A) ILD>30% or 10%20% or 20% with FVC%<70%. MRI Sensitivity, Specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV) and Accuracy were assessed. Pearson correlation coefficients r (p-value<0.025) were computed between ILD extents and PFT (FVC% and DLCO%).

RESULTS

Median ILD extents were 11%, 11%, 10% on CT, radial TSE and UTE, respectively. CCC between CT and MRI was 0.95 for both sequences (Kruskal-Wallis p-value=0.64). Sensitivity, Specificity, PPV, NPV and Accuracy in identifying extended disease were: (A) 87.5 %, 100 %, 100 %, 95.5 and 96.6 % with radial TSE and 87.5 %, 95.2 %, 87.5 %, 95.2 and 93.1 % with UTE; (B) 86.7 %, 86.4 %, 66.7 %, 95.0 % and 86.2 % for both sequences. Pearson r of CT, radial TSE and UTE ILD extents with FVC were -0.66, -0.60 and -0.68 with FVC, -0.59, -0.56 and -0.57 with DLCO, respectively (p<0.002).

CONCLUSIONS

MRI sequences may have similar accuracy to CT to determine SSc-ILD extent and severity, with analogous correlations with PFT.