The authors of the article prove the need to include a new name for the disease - \"Progressive Fibrosing Lung Disease\" into clinical practice. Recognition of the fact that some lung diseases end in a fibrosing process, which does not have any significant differences depending on the initial disease that led to fibrosis, will expand the indications for earlier prescription of antifibrotic drugs, which will undoubtedly improve the prognosis in this extremely severe category of patients.
В статье обосновывается необходимость включения в клиническую практику нового названия болезни – «прогрессирующая фиброзирующая болезнь легких». Признание факта исхода части заболеваний легких в фиброзирующий процесс, который существенно не различается в зависимости от исходного заболевания, приведшего к фиброзированию, позволит расширить показания для более раннего назначения антифибротических препаратов, что, несомненно, улучшит прогноз у этой крайне тяжелой категории пациентов.

The pathogenesis of idiopathic pulmonary fibrosis (IPF) and its histological counterpart, usual interstitial pneumonia (UIP) remains debated. IPF/UIP is a disease characterised by respiratory restriction, and while there have been recent advances in treatment, mortality remains high. Genetic and environmental factors predispose to its development and aberrant alveolar repair is thought to be central. Following alveolar injury, the type II pneumocyte (AEC2) replaces the damaged thin type I pneumocytes. Despite the interstitial fibroblast being considered instrumental in formation of the fibrosis, there has been little consideration for a role for AEC2 in the repair of the septal interstitium. Elastin is a complex protein that conveys flexibility and recoil to the lung. The fibroblast is presumed to produce elastin but there is evidence that the AEC2 may have a role in production or deposition. While the lung is an elastic organ, the role of elastin in repair of lung injury and its possible role in UIP has not been explored in depth. In this paper, pathogenetic mechanisms of UIP involving AEC2 and elastin are reviewed and the possible role of AEC2 in elastin generation is proposed.

Rationale: In 2018, a systematic review evaluating transbronchial lung cryobiopsy (TBLC) in patients with interstitial lung disease (ILD) was performed to inform American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax clinical practice guidelines on the diagnosis of idiopathic pulmonary fibrosis. Objectives: To perform a new systematic review to inform updated guidelines. Methods: Medline, Excerpta Medica Database, and the Cochrane Central Register of Controlled Trials (CCTR) were searched through June 2020. Studies that enrolled patients with ILD and reported the diagnostic yield or complication rates of TBLC were selected for inclusion. Data was extracted and then pooled across studies via meta-analysis. The quality of the evidence was appraised using the grading of recommendations, assessment, development, and evaluation approach. Results: Histopathologic diagnostic yield (number of procedures that yielded a histopathologic diagnosis divided by the total number of procedures performed) of TBLC was 80% (95% confidence interval [CI], 76-83%) in patients with ILD. TBLC was complicated by bleeding and pneumothorax in 30% (95% CI, 20-41%) and 8% (95% CI, 6-11%) of patients, respectively. Procedure-related mortality, severe bleeding, prolonged air leak, acute exacerbation, respiratory failure, and respiratory infection were rare. The quality of the evidence was very low owing to the uncontrolled study designs, lack of consecutive enrollment, and inconsistent results. Conclusions: Very low-quality evidence indicated that TBLC has a diagnostic yield of approximately 80% in patients with ILD, with manageable complications.

COVID-19 pneumonia represents a challenging health emergency, due to the disproportion between the high transmissibility, morbidity, and mortality of the virus and healthcare systems possibilities. Literature has mainly focused on COVID-19 pneumonia clinical-radiological diagnosis and therapy, and on the most common differential diagnoses, while few papers investigated rare COVID-19 pneumonia differential diagnoses or the overlapping of COVID-19 pneumonia on pre-existing lung pathologies. This article presents the main radiological characteristics of COVID-19 pneumonia and Idiopathic Interstitial Pneumonias (IIPs) to identify key radiological features for a differential diagnosis among IIPs, and between IIPs and COVID-19 pneumonia. COVID-19 pneumonia differential diagnosis with IIPs is challenging, since these entities may share common radiological findings as ground glass opacities, crazy paving patterns, and consolidations. Multidisciplinary discussion is crucial to reach a final and correct diagnosis. Radiologists have a pivotal role in identifying COVID-19 pneumonia patterns, reporting possible overlapping with long-lasting lung diseases, and suggesting potential differential diagnoses. An optimal evaluation of HRTC may help in containing the disease, in promoting better treatment for patients, and in providing an efficient allocation of human and economic resources.

Lung cancer is an important complication of combined pulmonary fibrosis and emphysema (CPFE). Whether the risk of lung cancer is higher in CPFE patients with usual interstitial pneumonia (UIP) than those with idiopathic pulmonary fibrosis (IPF) alone, remains controversial. We conducted this systematic review and meta-analysis to evaluate the prevalence of lung cancer in CPFE patients with UIP compared with IPF patients.
We searched the PubMed, Embase, and Cochrane databases for studies that focused on the incidence of lung cancer in CPFE/UIP and IPF groups. We used a fixed-effects model to analyze the odds ratios (ORs) with 95% confidence intervals (CIs) according to data heterogeneity. The cumulative effects based on the publication year and sample size were assessed by cumulative meta-analysis.
A total of nine studies with 933 patients, including 374 CPFE patients with UIP, fulfilled the inclusion criteria. Overall, CPFE patients with UIP have a higher risk of lung cancer than those with IPF alone (OR = 2.69; 95% CI: 1.78-4.05). There were increased risks of lung cancer in CPFE/UIP patients with the presence of emphysema (OR = 2.93; 95% CI: 1.79-4.79) or emphysema in ⩾10% of the lung volume (OR = 2.22; 95% CI: 1.06-4.68).
Our systematic review and meta-analysis indicated a significantly higher prevalence of lung cancer in CPFE patients with UIP than in patients with IPF alone.The reviews of this paper are available via the supplemental material section.

An important extra-articular manifestation of rheumatoid arthritis (RA) is interstitial lung disease (ILD). The relationship between the usual interstitial pneumonia (UIP) pattern and mortality in patients with RA is unclear. The purpose of this study was to complete a systematic literature review and meta-analysis on the association between RA-ILD pattern and mortality risk.
We performed a systematic literature review through December 12, 2018. Study characteristics, unadjusted and adjusted relative risks (RR) of mortality for ILD pattern were extracted from the identified studies and quality assessments were performed. RR for mortality (RA-UIP vs. other RA-ILD) was pooled using inverse variance weighting and random effects models.
Ten retrospective cohort studies met our eligibility criteria. A total of 1256 RA-ILD patients were included with 484 total deaths. Meta-analysis yielded a pooled RR of 1.66 (95% confidence interval1.07 to 2.56) for death among those with UIP RA-ILD compared with other patterns. In sub-group analysis when pooling studies comparing UIP to NSIP pattern of RA-ILD, the RR was 2.39 (95% CI 0.86-6.68).
Through a systematic literature review and meta-analysis, we found UIP pattern to be associated with a higher mortality risk in RA-ILD compared to other patterns of RA-ILD although more recent studies emphasize the importance of pulmonary physiology and the extent of lung involvement as significant predictors of mortality rather than the pattern of RA-ILD. Recognizing the small number of studies satisfying eligibility and inconsistent accounting for confounders, further study of mortality risk in RA-ILD is needed with standardized assessment of various RA, ILD, and patient-related factors.

Idiopathic interstitial pneumonias (IIP) are a heterogeneous group characterized by unknown aetiology. Establishment of a correct diagnosis of a distinct IIP requires a multidisciplinary approach integrating clinical presentation, physiological data, radiological appearance and histological findings. The 2013 update of the American Thoracic Society/European Respiratory Society classification summarises progress in the field of IIP and outlines potential areas for future research. The main entities defined by the 2002 statement on IIP are preserved, but major IIP are now distinguished from rare IIP and the new category of unclassifiable IIP is introduced. In addition, the existence of idiopathic non-specific interstitial pneumonia as a separate chronic fibrosing IIP and idiopathic pleuroparenchymal fibroelastosis as a specific rare entity are acknowledged. Moreover, the major IIP are categorized according to the features chronic fibrosing, smoking-related and acute/subacute clinical course. Furthermore, a clinical classification of IIP according to disease behaviour with suggestions for treatment goals and monitoring strategies is provided. The goal of this review is to discuss the areas of uncertainty in the updated multidisciplinary classification of IIP and point out potential consequences for clinical management.