A cohort study of mortality predictors and characteristics of patients with combined pulmonary fibrosis and emphysema

Serum Krebs von den Lungen-6 as a potential biomarker for distinguishing combined pulmonary fibrosis and emphysema from chronic obstructive pulmonary disease: A retrospective study

Background

The presence of fibrotic interstitial lung disease (ILD) is relatively common in patients with emphysema. This has been designated combined pulmonary fibrosis and emphysema (CPFE). CPFE had worse prognosis than emphysema alone. Krebs von den Lungen-6 (KL-6) levels as a biomarker of alveolar type 2 epithelial cell injury, which is widely used to identify the presence of ILD, whether it can differentiate CPFE from COPD remains unknown.

Methods

259 patients from Xiangya Hospital with diagnosis of COPD, with or without ILD, and who had KL-6 tests were recruited for this retrospective analysis. Recorded data included demographic information, comorbidities, inflammatory biomarkers. Results of CT and pulmonary function tests were collected one week before or after KL-6 measurements.

Results

Among 259 patients, 52 patients were diagnosed with CPFE. The mean age was 67.39 ± 8.14 yeas. CPFE patients had higher ratio of rheumatic diseases (21.2 % vs 7.2 %, P = 0.003). CPFE patients exhibited higher values of FEV1 (1.97 vs 1.57, P = 0.002) and FEV1/FVC ratio (69.46 vs 57.64, P < 0.001) compared to COPD patients. CPFE patients had higher eosinophil counts, percentage of eosinophils, lactate dehydrogenase, total bilirubin levels and lower platelet counts. Serum KL-6 levels were higher in CPFE group compared to COPD group (574.95 vs 339.30 U/mL, P < 0.001). Multiple logistic regression showed that KL-6 level was an independent predictive factor for the presence of ILD among COPD patients. The AUC of serum KL-6 levels to differentiate CPFE was 0.711, with 95 % CI being 0.635 to 0.787. The cutoff point of KL-6 level was 550.95 U/mL with 57.7 % sensitivity and 79.7 % specificity for the discrimination of CPFE from COPD.

Conclusion

CPFE patients show higher KL-6 levels compared to isolated COPD, suggesting the potential of KL-6 as a practical screening tool for interstitial lung disease, specifically CPFE. A KL-6 threshold of 550.95 U/mL in COPD patients may indicate a high need for high-resolution chest computed tomography to detect fibrosis.

The Impact of Lung Cancer in Patients with Combined Pulmonary Fibrosis and Emphysema (CPFE)

Given the high risk of lung cancer (LC) in patients with combined pulmonary fibrosis and emphysema (CPFE), and the difficulty of early diagnosis, it is important to understand the impact of LC in these patients. The effect of LC on the development of acute exacerbation (AE) as a natural course of CPFE is still unknown. We retrospectively reviewed medical records of patients at the West China Hospital and enrolled 59 patients with CPFE combined with LC and 68 CPFE patients without LC for initial diagnosis matched in the same period. We compared the clinical characteristics and imaging features of CPFE patients with LC and without LC, and analyzed the associated factors for the prevalence of LC using binary logistic regression. Cox proportional hazards regression analysis was performed to explore risk factors of AE as a natural course of CPFE. Patients with CPFE combined with LC were more common among elderly male smokers. The most common pathological type of tumor was adenocarcinoma (24/59, 40.7%) and squamous cell carcinoma (18/59, 30.5%). Compared with those in the without LC group, the proportions of men, and ex- or current smokers, and the levels of smoking pack-years, serum CRP, IL-6, fibrinogen, complement C3 and C4 in patients with LC were significantly higher (p < 0.05). There was no significant difference in the proportion of natural-course-related AE (10.2% vs. 16.2%, p > 0.05) between the two groups. Logistic regression analysis demonstrated that pack-years ≥ 20 (OR: 3.672, 95% CI: 1.165-11.579), family history of cancer (OR: 8.353, 95% CI: 2.368-10.417), the level of fibrinogen > 4.81 g/L (OR: 3.628, 95% CI: 1.403-9.385) and serum C3 > 1.00 g/L (OR: 5.299, 95% CI: 1.727-16.263) were independently associated with LC in patients with CPFE. Compared to those without AE, CPFE patients with AE had significantly higher levels of PLR and serum CRP, with obviously lower DLCO and VC. The obviously increased PLR (HR: 3.731, 95% CI: 1.288-10.813), and decreased DLCO%pred (HR: 0.919, 95% CI: 0.863-0.979) and VC%pred (HR: 0.577, 95% CI: 0.137-0.918) rather than the presence of LC independently contributed to the development of natural-course-related AE in patients with CPFE. Pack-years, family history of cancer, the levels of fibrinogen and serum C3 were independently associated with LC in patients with CPFE. The presence of LC did not significantly increase the risk of AE as a natural course of CPFE. Clinicians should give high priority to CPFE patients, especially those with more severe fibrosis and systemic inflammation, in order to be alert for the occurrence of AE.

Prognosis of acute exacerbation in idiopathic pulmonary fibrosis with pulmonary emphysema: a retrospective cohort study in Japan

OBJECTIVES

To analyse the clinical characteristics and prognosis of acute exacerbation (AE) in patients with idiopathic pulmonary fibrosis (IPF) and pulmonary emphysema.

DESIGN

A multicentre retrospective cohort study SETTING: Two university hospitals in Japan PARTICIPANTS: Patients admitted to hospitals due to AE of IPF diagnosed based on a multidisciplinary discussion.

INTERVENTIONS

None PRIMARY AND SECONDARY OUTCOME MEASURES: 90-day mortality rate METHODS: We retrospectively analysed consecutive patients with AE of IPF, with or without pulmonary emphysema, admitted to two university hospitals between 2007 and 2018.

RESULTS

Among 62 patients (median age, 75 years; 48 men) admitted for AE of IPF, 29 patients (46%) presented with concomitant pulmonary emphysema. There was no significant difference in the arterial partial oxygen pressure/fraction of inhaled oxygen (P/F) ratio or other laboratory and radiographic data between patients with and without emphysema. The 90-day mortality rate was significantly lower in patients with emphysema than in those with IPF alone (23% vs 52%, p=0.03). The median survival time was significantly longer in patients with emphysema than in those with IPF alone (405 vs 242 days, p=0.02).

CONCLUSION

Patients with IPF and emphysema had better short-term survival after AE than those with non-emphysematous IPF.

Syndrome of Combined Pulmonary Fibrosis and Emphysema: An Official ATS/ERS/JRS/ALAT Research Statement

Background: The presence of emphysema is relatively common in patients with fibrotic interstitial lung disease. This has been designated combined pulmonary fibrosis and emphysema (CPFE). The lack of consensus over definitions and diagnostic criteria has limited CPFE research. Goals: The objectives of this task force were to review the terminology, definition, characteristics, pathophysiology, and research priorities of CPFE and to explore whether CPFE is a syndrome. Methods: This research statement was developed by a committee including 19 pulmonologists, 5 radiologists, 3 pathologists, 2 methodologists, and 2 patient representatives. The final document was supported by a focused systematic review that identified and summarized all recent publications related to CPFE. Results: This task force identified that patients with CPFE are predominantly male, with a history of smoking, severe dyspnea, relatively preserved airflow rates and lung volumes on spirometry, severely impaired DlCO, exertional hypoxemia, frequent pulmonary hypertension, and a dismal prognosis. The committee proposes to identify CPFE as a syndrome, given the clustering of pulmonary fibrosis and emphysema, shared pathogenetic pathways, unique considerations related to disease progression, increased risk of complications (pulmonary hypertension, lung cancer, and/or mortality), and implications for clinical trial design. There are varying features of interstitial lung disease and emphysema in CPFE. The committee offers a research definition and classification criteria and proposes that studies on CPFE include a comprehensive description of radiologic and, when available, pathological patterns, including some recently described patterns such as smoking-related interstitial fibrosis. Conclusions: This statement delineates the syndrome of CPFE and highlights research priorities.

Chronic Obstructive Pulmonary Disease Combined with Interstitial Lung Disease

Although chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) have distinct clinical features, both diseases may coexist in a patient because they share similar risk factors such as smoking, male sex, and old age. Patients with both emphysema in upper lung fields and diffuse ILD are diagnosed with combined pulmonary fibrosis and emphysema (CPFE), which causes substantial clinical deterioration. Patients with CPFE have higher mortality compared with patients who have COPD alone, but results have been inconclusive compared with patients who have idiopathic pulmonary fibrosis (IPF). Poor prognostic factors for CPFE include exacerbation, lung cancer, and pulmonary hypertension. The presence of interstitial lung abnormalities, which may be an early or mild form of ILD, is notable among patients with COPD, and is associated with poor prognosis. Various theories have been proposed regarding the pathophysiology of CPFE. Biomarker analyses have implied that this pathophysiology may be more closely associated with IPF development, rather than COPD or emphysema. Patients with CPFE should be advised to quit smoking and undergo routine lung function tests, and pulmonary rehabilitation may be helpful. Various pharmacologic agents and surgical approaches may be beneficial in patients with CPFE, but further studies are needed.

Serum Krebs von den Lungen-6: promising biomarker to differentiate CPFE from IPF

Background   Combined pulmonary fibrosis and emphysema (CPFE) has been recognised as a phenotype of pulmonary fibrosis. We aimed to compare serum surfactant protein-A (SP-A), surfactant protein-D (SP-D) and Krebs von den Lungen-6 (KL-6) levels, functional parameters, in CPFE and  IPF (idiopathic pulmonary fibrosis) patients. Methods Patients diagnosed with 'CPFE' and 'IPF' were consecutively included in 6 months as two groups. The patients with connective tissue diseases are excluded. Results           In this study, 47 patients (41 males, 6 females) with CPFE (n = 21) and IPF (n = 26) with a mean age of 70.12 ± 8.75 were evaluated. CPFE patients were older, had more intense smoking history, had lower DLCO/VA, lower FVC, and worse six-minute walking distance than the IPF group (p=0.005, p=0.027, p=0.02, p<0.001, p=0.001, respectively). Serum KL-6 levels were higher in CPFE group compared to IPF group [264.70 U/ml (228.90-786) vs 233.60 (101.8-425.4), p<0.001]. Serum KL-6 levels of 245.4 U/ml and higher have 81% sensitivity and 73% specificity for the discrimination of CPFE from IPF. Conclusions   Our study has shown that serum KL-6 level is a promising biomarker to differentiate CPFE from IPF. In CPFE cases respiratory and functional parameters are worse than those of pure fibrosis cases.

KL-6 as an Immunological Biomarker Predicts the Severity, Progression, Acute Exacerbation, and Poor Outcomes of Interstitial Lung Disease: A Systematic Review and Meta-Analysis

Object

Interstitial lung disease (ILD) is a specific form of chronic fibrosing interstitial pneumonia with various etiology. The severity and progression of ILD usually predict the poor outcomes of ILD. Otherwise, Krebs von den Lungen-6 (KL-6) is a potential immunological biomarker reflecting the severity and progression of ILD. This meta-analysis is to clarify the predictive value of elevated KL-6 levels in ILD.

Method

EBSCO, PubMed, and Cochrane were systematically searched for articles exploring the prognosis of ILD published between January 1980 and April 2021. The Weighted Mean Difference (WMD) and 95% Confidence Interval (CI) were computed as the effect sizes for comparisons between groups. For the relationship between adverse outcome and elevated KL-6 concentration, Hazard Ratio (HR), and its 95%CI were used to estimate the risk factor of ILD.

Result

Our result showed that ILD patients in severe and progressive groups had higher KL-6 levels, and the KL-6 level of patients in the severe ILD was 703.41 (U/ml) than in mild ILD. The KL-6 level in progressive ILD group was 325.98 (U/ml) higher than that in the non-progressive ILD group. Secondly, the KL-6 level of patients in acute exacerbation (AE) of ILD was 545.44 (U/ml) higher than stable ILD. Lastly, the higher KL-6 level in ILD patients predicted poor outcomes. The KL-6 level in death of ILD was 383.53 (U/ml) higher than in survivors of ILD. The pooled HR (95%CI) about elevated KL-6 level predicting the mortality of ILD was 2.05 (1.50–2.78), and the HR (95%CI) for progression of ILD was 1.98 (1.07–3.67).

Conclusion

The elevated KL-6 level indicated more severe, more progressive, and predicted the higher mortality and poor outcomes of ILD.

Prognostic role of Krebs von den Lungen-6 (KL-6) measurement in idiopathic pulmonary fibrosis: a systematic review and meta-analysis

OBJECTIVES

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial disease with limited therapeutic options. The measurement of Krebs von den Lungen-6 (KL-6) glycoprotein has been proposed for evaluating the risk of IPF progression and predicting patient prognosis, but the robustness of available evidence is unclear.

METHODS

We searched Medline and Embase databases for peer-reviewed literature from inception to April 2020. Original articles investigating KL-6 as prognostic marker for IPF were retrieved. Considered outcomes were the risk of developing acute exacerbation (AE) and patient survival. Meta-analysis of selected studies was conducted, and quantitative data were uniformed as odds ratio (OR) or hazard ratio (HR) estimates, with corresponding 95% confidence intervals (CI).

RESULTS

Twenty-six studies were included in the systematic review and 14 were finally meta-analysed. For AE development, the pooled OR (seven studies) for KL-6 was 2.72 (CI 1.22-6.06; p=0.015). However, a high degree of heterogeneity (I²=85.6%) was found among selected studies. Using data from three studies reporting binary data, a pooled sensitivity of 72% (CI 60-82%) and a specificity of 60% (CI 52-68%) were found for KL-6 measurement in detecting insurgence of AE in IPF patients. Pooled HR (seven studies) for mortality prediction was 1.009 (CI 0.983-1.036; p=0.505).

CONCLUSIONS

Although our meta-analysis suggested that IPF patients with increased KL-6 concentrations had a significant increased risk of developing AE, the detection power of the evaluated biomarker is limited. Furthermore, no relationship between biomarker concentrations and mortality was found. Caution is also needed when extending obtained results to non-Asian populations.

Serum KL-6 Could Represent a Reliable Indicator of Unfavourable Outcome in Patients with COVID-19 Pneumonia

KL-6 is a sialoglycoprotein antigen which proved elevated in the serum of patients with different interstitial lung diseases, especially in those with a poorer outcome. Given that interstitial pneumonia is the most common presentation of SARS-CoV2 infection, we evaluated the prognostic role of KL-6 in patients with COVID-19 pneumonia. Patients with COVID-19 pneumonia were prospectively enrolled. Blood samples were collected at the time of enrolment (TOE) and on day 7 (T1). Serum KL-6 concentrations were measured by chemiluminescence enzyme immunoassay using a KL-6 antibody kit (LUMIPULSE G1200, Fujirebio) and the cut-off value was set at >1000 U/mL. Fifteen out of 34 enrolled patients (44.1%) died. Patients with unfavourable outcome showed significantly lower P/F ratio and higher IL-6 values and plasmatic concentrations of KL-6 at TOE compared with those who survived (median KL-6: 1188 U/mL vs. 260 U/mL, p < 0.001). KL-6 > 1000 U/mL resulted independently associated with death (aOR: 11.29, p < 0.05) with a positive predictive value of 83.3%. Our results suggest that KL-6 is a reliable indicator of pulmonary function and unfavourable outcome in patients with COVID-19 pneumonia. A KL-6 value > 1000 U/mL resulted independently associated with death and showed good accuracy in predicting a poorer outcome. KL-6 may thus represent a quick, inexpensive, and sensitive parameter to stratify the risk of severe respiratory failure and death.

Lung cancer in combined pulmonary fibrosis and emphysema: a large retrospective cohort analysis

Background

Combined pulmonary fibrosis and emphysema (CPFE) is characterised by upper lobe emphysema and lower lobe fibrosis. Our study aim was to determine the incident risk, presenting characteristics and outcome of lung cancer diagnoses in a cohort of CPFE patients over time.

Materials and methods

We conducted a retrospective cohort study assessing patients with radiological CPFE followed over a median of 76 months (range 1–237 months). Interval development of lung cancer and clinicopathological characteristics of those with and without lung cancer were compared and survival analysis performed.

Results

Lung cancer occurred in 26 (11.6%) out of 230 CPFE patients, dominated by nonsmall cell lung cancer (88%, n=23) with squamous cell carcinoma comprising the majority (57%, n=13). There was a predominance of lower lobe (62%) and subpleural (64%) radiological presentation. Survival was reduced for the whole cohort by lung cancer even after adjusting for a priori covariables of age, sex, smoking pack-years, presenting forced vital capacity and radiological honeycombing. Univariable predictors of increased mortality after lung cancer diagnosis included honeycombing (hazard ratio (HR) 3.03, 95% CI 1.16–7.91; p=0.02) and later stage presentation (HR 4.77, 95% CI 1.8–14.94; p=0.001), with those able to undergo surgical resection having better survival (HR 0.29, 95% CI 0.09–0.87; p=0.02).

Conclusion

Lung cancer occurred in 26 (11.6%) out of 230 CPFE patients and was dominated by squamous cell carcinoma presenting in a lower lobe peripheral distribution. Surgical resection appeared to improve survival in selected patients with earlier stage disease. Further studies are needed to develop a relevant screening programme for CPFE patients.

Lung cancer is common in CPFE patients followed over time, with possibly better survival in those diagnosed at earlier stages and successfully resected. Further studies to formulate disease-specific cancer screening protocols are needed.https://bit.ly/3445Bxr

Objective quantitative multidetector computed tomography assessments in patients with combined pulmonary fibrosis with emphysema: Relationship with pulmonary function and clinical events

BACKGROUND

Combined pulmonary fibrosis with emphysema (CPFE) is a clinically meaningful syndrome characterized by coexisting upper-lobe emphysema and lower-lobe interstitial fibrosis. However, ambiguous diagnostic criteria and, particularly, the absence of objective methods to quantify emphysematous/fibrotic lesions in patients with CPFE confound the interpretation of the pathophysiology of this syndrome. We analyzed the relationship between objectively quantified computed tomography (CT) measurements and the results of pulmonary function testing (PFT) and clinical events in CPFE patients.

MATERIALS AND METHODS

We enrolled 46 CPFE patients who underwent CT and PFT. The extent of emphysematous lesions was obtained by calculating the percent of low attenuation area (%LAA). The extent of fibrotic lesions was calculated as the percent of high attenuation area (%HAA). %LAA and %HAA values were combined to yield the percent of abnormal area (%AA). We assessed the relationships between CT parameters and other clinical indices, including PFT results. Multivariate analysis was performed to examine the association between the CT parameters and clinical events.

RESULTS

A greater negative correlation with percent predicted diffusing capacity of the lung for carbon monoxide (DLCO %predicted) existed for %AA (r = -0.73, p < 0.001) than for %LAA or %HAA alone. The %HAA value was inversely correlated with percent predicted forced vital capacity (r = -0.48, p < 0.001), percent predicted total lung capacity (r = -0.48, p < 0.01), and DLCO %predicted (r = -0.47, p < 0.01). Multivariate logistic regression analysis found that %AA showed the strongest association with hospitalization events (odds ratio = 1.20, 95% confidence interval = 1.01-1.54, p = 0.029).

CONCLUSION

Quantitative CT measurements reflected deterioration in pulmonary function and were associated with hospitalization in patients with CPFE. This approach could serve as a useful method to determine the extent of lung morphology, pathophysiology, and the clinical course of patients with CPFE.

Acute exacerbations of COPD versus IPF in patients with combined pulmonary fibrosis and emphysema

RATIONALE

Patients with combined pulmonary fibrosis and emphysema (CPFE) may develop acute exacerbations of IPF (AE-IPF) or COPD (AE-COPD). The incidence and the characteristics of exacerbations in patients with CPFE (e.g., COPD vs IPF) have not been well described.

OBJECTIVES

To compare the incidence and rate of exacerbations in patients with CPFE vs. IPF and evaluate their effect on clinical outcomes.

METHODS

Comprehensive clinical data from CPFE and IPF patients were retrospectively reviewed. Baseline characteristics including lung function data, oxygen requirements, and pulmonary hemodynamics, were collected. Acute exacerbation events in both groups were defined clinically and radiographically. In the CPFE group, two patterns of exacerbations were identified. AE-COPD was defined clinically by symptoms of severe airflow obstruction causing respiratory failure and requiring hospitalization. Radiographic data were also defined based on previously published literature. AE-IPF was defined clinically as an acute hypoxic respiratory failure, requiring hospitalization and treatment with high dose corticosteroids. Radiographically, patients had to have a change in baseline imaging including presence of ground-glass opacities, interlobular septal thickening or new consolidations; that is not fully explained by other etiologies.

RESULTS

Eighty-five CPFE patients were retrospectively compared to 112 IPF patients. Of 112 patients with IPF; 45 had AE-IPF preceding lung transplant (40.18%) compared to 12 patients in the CPFE group (14.1%) (p < 0.05). 10 patients in the CPFE group experienced AE-COPD (11.7%). Patients with AE-IPF had higher mortality and more likely required mechanical ventilation and extracorporeal membrane oxygenation (ECMO) compared to patients with AE-COPD, whether their underlying disease was IPF or CPFE.

CONCLUSIONS

CPFE patients may experience either AE-IPF or AE-COPD. Patients with CPFE and AE-COPD had better outcomes, requiring less intensive therapy compared to patients with AE-IPF regardless if underlying CPFE or IPF was present. These data suggest that the type of acute exacerbation, AE-COPD vs AE-IPF, has important implications for the treatment and prognosis of patients with CPFE.

Characteristics of tobacco-related lung diseases in Fukuoka Prefecture, Japan: A prospective, multi-institutional, observational study

BACKGROUND

Tobacco smoking causes a variety of smoking-related diseases, death, and economic damage. Despite targeted anti-smoking campaigns, tobacco-related deaths are expected to increase in Japan. We investigated the current state of non-cancerous lung diseases such as idiopathic interstitial pneumonias (IIPs), chronic obstructive pulmonary disease (COPD), and combined pulmonary fibrosis and emphysema (CPFE), which are known to be highly related to tobacco smoking.

METHODS

This prospective multi-institutional observational study involved 29 major hospitals within the Fukuoka Prefecture area (Fukuoka tobacco-related lung disease registry study group). Patients diagnosed with IIPs, including CPFE and COPD, registered from September 1, 2013 to April 30, 2016 were included. Clinical background information, laboratory and pulmonary function test results, findings of imaging tests, including chest radiography and chest computed tomography, and DNA isolated from peripheral blood were collected from each patient. Follow-up surveillance involved collection of data regarding the exacerbation of disease and death until 5 years of registration. In the present study, we report the baseline characteristics of the patients registered in this surveillance study.

RESULTS

Overall, 1016 patients (524 with IIPs, including 145 CPFE and 492 with COPD) were enrolled. Among the patients with COPD, 96.8% were current or former smokers. Among the patients with IIPs, 69.9% were current or former smokers.

CONCLUSION

This study revealed the current status of lung diseases potentially related to tobacco smoking in Fukuoka Prefecture. Both COPD and CPFE were highly related to tobacco smoking, whereas 30% of patients with IIPs had never smoked.

Comparing effectiveness of prognostic tests in idiopathic pulmonary fibrosis

Introduction: Idiopathic pulmonary fibrosis (IPF) is a debilitating and progressive fibrotic interstitial lung disease often resulting in death over several years. Prediction of disease course or survival remains of keen interest for clinicians and patients though a commonly used test or tool remain elusive. Areas covered: We undertook a comprehensive review of the published literature highlighting prognostic indicators and predictors of survival in IPF. Baseline and longitudinal clinical, functional, histopathologic, and radiologic findings have been extensively studied as prognostic predictors, both individually and in composite models. Recent approaches include automated quantifiable radiologic scoring, circulating biomarkers, and genetic polymorphisms or abnormalities. This review highlights individual and composite predictors and their relative utility in clinical practice and research studies. Expert opinion: There is a growing body of knowledge highlighting readily available individual and composite predictors of outcome, though none have come to the forefront for common clinical use. Recent advances include quantitative imaging analysis, circulating serologic markers, and genetic testing, which may be more standardized and less prone to lead-time bias or related complications and comorbidities.

Evaluation and management of Idiopathic Pulmonary Fibrosis

Idiopathic Pulmonary Fibrosis (IPF) is a most common progressive interstitial lung disease (ILD) of unknown etiology, although majority of patients are elderly male smokers. The main pathogenesis is aberrant recovery of epithelial injury and collagen deposition. Fibrotic nonspecific interstitial pneumonia, connective tissue disease (CTD) especially rheumatoid arthritis (RA) associated ILD, and chronic hypersensitivity pneumonia(CHP) are important differential diagnosis. Main symptoms are non-productive cough and progressive exertional dyspnea. Crucial physical findings are scalene muscle hypertrophy, bibasilar fine crackles, and finger clubbing. The serum markers such as lactate dehydrogenase (LDH) and Krebs von den Lungen-6 (KL-6) are sensitive for ILD detection and activity. Both pulmonary function test (PFT) and the 6-minute walk test (6MWT) are useful tool for evaluation of disease progression of IPF. Serial changes of forced vital capacity (FVC) and 6MWT distance predict mortality in IPF effectively. Recently published international IPF guidelines highlight the importance of chest high resolution computed tomography (HRCT) findings such as honeycombing, traction bronchiectasis (TBE), and sub-pleural reticular opacity. IPF is chronic and progressive; therefore, tracking disease behavior is crucial. Unifying clinical, physiological, and imaging information over time is useful. With regard to its management, two anti-fibrotic drugs such as pirfenidone and nintedanib have been available. These drugs can slow the decline of FVC and prevent acute exacerbation (AE). In this review, I outline the clinical characteristics of IPF, physiological, imaging, pathological findings and review diagnosis process and management.

Combined pulmonary fibrosis and emphysema as a clinicoradiologic entity: Characterization of presenting lung fibrosis and implications for survival

BACKGROUND

The prevalence of classifiable and unclassifiable causes of lung fibrosis and its implications for survival are mostly unknown in combined pulmonary fibrosis and emphysema (CPFE).

MATERIALS AND METHODS

Patients with >10% involvement of both emphysema and lung fibrosis seen over 11 years at our institution were reviewed independently by expert radiologists for fibrotic and emphysematous findings and overall fibrotic CT pattern. Underlying interstitial lung disease (ILD) diagnoses and baseline demographic and clinical characteristics were collated and assessed for predictors of comparative survival.

RESULTS

In this retrospective cohort, 179 CPFE patients were identified and categorized as 58 usual interstitial pneumonia/idiopathic pulmonary fibrosis (UIP/IPF) (32%), 42 secondary ILD (23%), and 79 unclassifiable ILD (44%). The most prevalent (47%) radiologic pattern was 'unclassifiable', followed by 'consistent' and 'possible' UIP pattern in 38%. Adjusted predictors of mortality for the cohort as a whole included age (HR 1.03[1.01-1.06], P = 0.002), percent predicted diffusing capacity for carbon monoxide (unit HR 0.97 [0.96-0.99], P = 0.001), honeycombing (HR 1.58 [1.02-2.43], P = 0.04), and right ventricular dysfunction (HR 2.28 [1.39-3.97], P = 0.002). Survival was similar between CPFE with secondary ILD and CPFE with UIP/IPF, while CPFE with unclassifiable ILD had better comparative survival (Log rank = 0.026).

CONCLUSIONS

Our findings suggest only about a third of CPFE patients represent suspected UIP/IPF; the majority were clinically and radiologically unclassifiable ILD whose survival was comparatively better. Identifiable or secondary causes of lung fibrosis in CPFE occurred in about a fifth of presenting patients.

Effects of emphysema on physiological and prognostic characteristics of lung function in idiopathic pulmonary fibrosis

BACKGROUND AND OBJECTIVE

Combined pulmonary fibrosis and emphysema (CPFE) is characterized by preserved lung volume and slower lung function decline. However, it is unclear at what extent emphysema begins to impact respiratory physiology and prognostic characteristics in idiopathic pulmonary fibrosis (IPF). We estimated the extent of emphysema that could be used to define CPFE in IPF.

METHODS

The extent of emphysema was observed on high-resolution computed tomography scans and measured by a texture-based automated quantification system in 209 IPF patients. We analysed the impact of differences in the extent of emphysema on the annual decline rate and prognostic significance of lung function parameters.

RESULTS

The extent of emphysema was ≥5% in 53 patients (25%), ≥10% in 23 patients (11%) and ≥15% in 12 patients (6%). Patients with emphysema to an extent of ≥5% were more frequently men and ever-smokers; they had more preserved lung volume and lower forced vital capacity (FVC) decline rates than those with no or trivial emphysema. The FVC decline rate was a significant predictor of mortality in patients with no or trivial emphysema (hazard ratio (HR): 0.933, P < 0.001) and in patients with an extent of emphysema ≥5% (HR: 0.906, P < 0.001). However, diffusing capacity of the lung for carbon monoxide (DL_CO ) was the most significant prognostic factor in those patients with an extent of emphysema ≥10% (HR: 0.972, P = 0.040) and ≥15% (HR: 0.942, P = 0.023). A 10% cut-off value for the extent of emphysema created the most significant difference in the annual FVC decline rate in IPF patients.

CONCLUSION

In IPF, emphysema to an extent of ≥10% affects both the annual decline rate and the prognostic significance of FVC. This extent could be used to define CPFE.

Presence of lung cancer and high gender, age, and physiology score as predictors of acute exacerbation in combined pulmonary fibrosis and emphysema: A retrospective study

Combined pulmonary fibrosis and emphysema (CPFE) patients visit hospitals frequently due to acute exacerbations (AEs); however, the predictors of CPFE AE have not been comprehensively described in literature. Thus, we investigated the predicting factors of AE in CPFE patients.We retrospectively reviewed medical records from the past 12 years at Korea University Guro Hospital. We selected CPFE patients by computed tomography findings. Rapid deterioration (RD) was defined as acute worsening of dyspnea requiring hospitalization and the presence of newly developed radiologic abnormalities. AE was defined as RD with newly acquired bilateral pulmonary infiltrates without evidence of pulmonary infection or other known causes. We evaluated the following variables in CPFE patients: age, sex, smoking history and amount, body mass index, past medical history, pulmonary function test, gender, age, and physiology (GAP) score, and the presence of lung cancer.Among 227 CPFE patients, 108 had RD and 31 developed AE. The most common cause of RD was infection (n = 60, 55.6%) and 28.7% (n = 31) developed AE. Lung cancer [hazard ratio (HR), 3.274; 95% confidence interval (95% CI) 1.444-7.425; P < .01] and GAP score (HR, 1.434; 95% CI 1.072-1.918; P = .02) were significant predictors of AE. The presence of lung cancer and AE were significant predictors of mortality.In conclusion, CPFE patients with lung cancer and high GAP scores should be carefully observed for AE.

Management of acute respiratory failure in interstitial lung diseases: overview and clinical insights

Background

Interstitial lung diseases (ILDs) are a heterogeneous group of diseases characterized by widespread fibrotic and inflammatory abnormalities of the lung. Respiratory failure is a common complication in advanced stages or following acute worsening of the underlying disease. Aim of this review is to evaluate the current evidence in determining the best management of acute respiratory failure (ARF) in ILDs.

Methods

A literature search was performed in the Medline/PubMed and EMBASE databases to identify studies that investigated the management of ARF in ILDs (the last search was conducted on November 2017).

Results

In managing ARF, it is important to establish an adequate diagnostic and therapeutic management depending on whether the patient has an underlying known chronic ILD or ARF is presenting in an unknown or de novo ILD. In the first case both primary causes, such as acute exacerbations of the disease, and secondary causes, including concomitant pulmonary infections, fluid overload and pulmonary embolism need to be investigated. In the second case, a diagnostic work-up that includes investigations in regards to ILD etiology, such as autoimmune screening and bronchoalveolar lavage, should be performed, and possible concomitant causes of ARF have to be ruled out.

Oxygen supplementation and ventilatory support need to be titrated according to the severity of ARF and patients’ therapeutic options. High-Flow Nasal oxygen might potentially be an alternative to conventional oxygen therapy in patients requiring both high flows and high oxygen concentrations to correct hypoxemia and control dyspnea, however the evidence is still scarce. Neither Non-Invasive Ventilation (NIV) nor Invasive Mechanical Ventilation (IMV) seem to change the poor outcomes associated to advanced stages of ILDs. However, in selected patients, such as those with less severe ARF, a NIV trial might help in the early recognition of NIV-responder patients, who may present a better short-term prognosis. More invasive techniques, including IMV and Extracorporeal Membrane Oxygenation, should be limited to patients listed for lung transplant or with reversible causes of ARF.

Conclusions

Despite the overall poor prognosis of ARF in ILDs, a personalized approach may positively influence patients’ management, possibly leading to improved outcomes. However, further studies are warranted.

Serum concentrations of Krebs von den Lungen-6, surfactant protein D, and matrix metalloproteinase-2 as diagnostic biomarkers in patients with asbestosis and silicosis: a case-control study

BACKGROUND

Asbestosis and silicosis are progressive pneumoconioses characterized by interstitial fibrosis following exposure to asbestos or silica dust. We evaluated the potential diagnostic biomarkers for these diseases.

METHODS

The serum concentrations of Krebs von den Lungen-6 (KL-6), surfactant protein D (SP-D), and matrix metalloproteinase-2 (MMP-2), MMP-7, and MMP-9 were measured in 43 patients with asbestosis, 45 patients with silicosis, 40 dust-exposed workers (DEWs) without pneumoconiosis, and 45 healthy controls (HCs). Chest high-resolution computed tomography (HRCT) images were reviewed by experts blinded to the clinical data. According to the receiver operating characteristic (ROC) curve, the ideal level of each biomarker and its diagnostic sensitivity were obtained.

RESULTS

The serum KL-6 and MMP-2 concentrations were highest in patients with asbestosis, particularly in comparison with those in DEWs and HCs (P<0.05). The serum SP-D concentration was significantly higher in patients with asbestosis than in patients with silicosis, DEWs, and HCs (P<0.01), whereas no significant difference was noted among patients with silicosis, DEWs, and HCs. No significant difference in the serum MMP-7 or -9 concentration was found among patients with asbestosis, patients with silicosis, DEWs, or HCs. Among patients with asbestosis, the serum KL-6 concentration was significantly correlated with the lung fibrosis scores on HRCT and negatively correlated with the forced vital capacity (FVC) % predicted and diffusing capacity of the lung for carbon monoxide (DL_CO) % predicted. The serum SP-D and MMP-2 concentrations were negatively correlated with the DL_CO % predicted (all P<0.05). The order of diagnostic accuracy according to the ROC curve was KL-6, SP-D, and MMP-2 in patients with asbestosis alone and in the combination of both patients with asbestosis and those with silicosis. The combination of all three biomarkers may increase the possibility of diagnosing asbestosis (sensitivity, 93%; specificity, 57%) and both asbestosis and silicosis (sensitivity, 83%; specificity, 62%).

CONCLUSIONS

KL-6, SP-D, and MMP-2 are available biomarkers for the adjuvant diagnosis of asbestosis and silicosis. The combination of all three biomarkers may improve the diagnostic sensitivity for asbestosis and silicosis.

Acute Exacerbation in Interstitial Lung Disease

Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) has been defined as an acute, clinically significant deterioration that develops within less than 1 month without obvious clinical cause like fluid overload, left heart failure, or pulmonary embolism. Pathophysiologically, damage of the alveoli is the predominant feature of AE-IPF which manifests histopathologically as diffuse alveolar damage and radiologically as diffuse, bilateral ground-glass opacification on high-resolution computed tomography. A growing body of literature now focuses on acute exacerbations of interstitial lung disease (AE-ILD) other than idiopathic pulmonary fibrosis. Based on a shared pathophysiology it is generally accepted that AE-ILD can affect all patients with interstitial lung disease (ILD) but apparently occurs more frequently in patients with an underlying usual interstitial pneumonia pattern. The etiology of AE-ILD is not fully understood, but there are distinct risk factors and triggers like infection, mechanical stress, and microaspiration. In general, AE-ILD has a poor prognosis and is associated with a high mortality within 6–12 months. Although there is a lack of evidence based data, in clinical practice, AE-ILD is often treated with a high dose corticosteroid therapy and antibiotics. This article aims to provide a summary of the clinical features, diagnosis, management, and prognosis of AE-ILD as well as an update on the current developments in the field.

Severe pulmonary hypertension due to combined pulmonary fibrosis and emphysema: another cause of death among smokers

In 2005, the combined pulmonary fibrosis and emphysema (CPFE) was first defined as a distinct entity, which comprised centrilobular or paraseptal emphysema in the upper pulmonary lobes, and fibrosis in the lower lobes accompanied by reduced diffused capacity of the lungs for carbon monoxide (DLCO). Recently, the fibrosis associated with the connective tissue disease was also included in the diagnosis of CPFE, although the exposure to tobacco, coal, welding, agrochemical compounds, and tire manufacturing are the most frequent causative agents. This entity characteristically presents reduced DLCO with preserved lung volumes and severe pulmonary hypertension, which is not observed in emphysema and fibrosis alone. We present the case of a 63-year-old woman with a history of heavy tobacco smoking abuse, who developed progressive dyspnea, severe pulmonary hypertension, and cor pulmonale over a 2-year period. She attended the emergency facility several times complaining of worsening dyspnea that was treated as decompensate chronic obstructive pulmonary disease (COPD). The imaging examination showed paraseptal emphysema in the upper pulmonary lobes and fibrosis in the middle and lower lobes. The echo Doppler cardiogram revealed the dilation of the right cardiac chambers and pulmonary hypertension, which was confirmed by pulmonary trunk artery pressure measurement by catheterization. During this period, she was progressively restricted to the minimal activities of daily life and dependent on caregivers. She was brought to the hospital neurologically obtunded, presenting anasarca, and respiratory failure, which led her to death. The autopsy showed signs of pulmonary hypertension and findings of fibrosis and emphysema in the histological examination of the lungs. The authors highlight the importance of the recognition of this entity in case of COPD associated with severe pulmonary hypertension of unknown cause.

Lung Cancer in Patients With Combined Pulmonary Fibrosis and Emphysema and Idiopathic Pulmonary Fibrosis. A Descriptive Study in a Spanish Series

INTRODUCTION

Information on the association of lung cancer (LC) and combined pulmonary fibrosis and emphysema (CPFE) is limited and derived almost exclusively from series in Asian populations. The main objective of the study was to assess the impact of LC on survival in CPFE patients and in patients with idiopathic pulmonary fibrosis (IPF).

METHODS

A retrospective study was performed with data from patients with CFPE and IPF diagnosed in our hospital over a period of 5 years.

RESULTS

Sixty-six patients were included, 29 with CPFE and 37 with IPF. Nine had a diagnosis of LC (6 with CPFE and 3 with IPF). Six patients (67%) received palliative treatment even though 3 of them were diagnosed atstage i-ii. Overall mortality did not differ significantly between groups; however, in patients with LC, survival was significantly lower compared to those without LC (P=.044). The most frequent cause of death was respiratory failure secondary to pulmonary fibrosis exacerbation (44%). In a multivariate analysis, the odds ratio of death among patients with LC compared to patients without LC was 6.20 (P=.037, 95% confidence interval: 1.11 to 34.48).

CONCLUSIONS

Lung cancer reduces survival in both entities. The diagnostic and therapeutic management of LC is hampered by the increased risk of complications after any treatment modality, even after palliative treatment.

Combined pulmonary fibrosis and emphysema: a retrospective analysis of clinical characteristics, treatment and prognosis

Background

Combined pulmonary fibrosis and emphysema (CPFE) is increasingly acknowledged as a separate syndrome with distinct clinical, physiological and radiological characteristics. We sought to identify physiologic and radiographic indices that predict mortality in CPFE.

Methods

Data on clinical characteristics, pulmonary function, high-resolution computed tomography (HRCT) and treatment were compared between patients with usual interstitial pneumonia (UIP) plus emphysema (CPFE group) and those with IPF alone (IPF group). Composite physiologic index (CPI) and HRCT scores at diagnosis and during follow-up were assessed.

Results

CPFE group (N = 87) was characterized by the predominance of males and smokers, who were less likely to have viral infection prior to the diagnosis, and display basal crackles, finger clubbing and wheeze, as compared to that in the IPF group (N = 105). HRCT and CPI scores increased over time in both groups. Moreover, CPFE group had a poorer prognosis, lower 5-year survival rate (43.42 % vs. 65.56 %; P < 0.05), and higher mortality (39.47 % vs. 23.33 %; P < 0.05) as compared to that in the IPF group. All CPFE patients received oxygen therapy, antibiotics and oral N-acetylcysteine; > 50 % received bronchodilators, 40 % received corticosteroids and 14 % needed noninvasive mechanical ventilation. On survival analyses, pulmonary arterial hypertension (PAH) and ≥ 5-point increase in CPI score per year were predictors of mortality in the CPFE group (hazard ratio [HR]: 10.29, 95 % Confidence Interval [CI]: 2.69–39.42 and HR: 21.60, 95 % CI: 7.28–64.16, respectively).

Conclusion

Patients with CPFE were predominantly male and smokers and exhibited distinct clinical, physiological and radiographic characteristics. They had a poorer prognosis than IPF. PAH and ≥ 5-point increase in CPI score per year were predictors of mortality in these patients. Future studies are needed to identify the optimal treatment approach to CPFE.

Clinical characteristics of idiopathic pulmonary fibrosis patients according to their smoking status

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is the most common form of idiopathic interstitial pneumonias (IIPs) of unknown etiology that often affects male, elderly smokers. However, it is sometimes observed in never smokers. This study aimed to clarify the clinical characteristics of IPF in never-smoking patients compared with those in smoking patients.

METHODS

We retrospectively reviewed medical records, pulmonary function tests, and chest high-resolution computed tomography (HRCT) scan of never-smoking and smoking IPF patients from July 1, 2008 to June 30, 2013 at our hospital.

RESULTS

We identified 32 never-smoking IPF patients and 66 smoking IPF patients. Never-smoking IPF patients developed more acute exacerbation (AE) than smoking IPF patients (50% vs. 18.2%, P<0.0001). The strongest predictor of AE in never-smoking IPF was modified Medical Research Council (mMRC) breathlessness scale [Hazards ratio (HR), 2.84, P=0.006]. The median survival time of never-smoking and smoking were 18.5 (0.1-138) and 26.3 (0.1-98.4) months, P<0.0001, respectively. The Cox proportional hazard model showed that 1-year mMRC breathlessness scale (HR, 3.24, P=0.001) and gender, age, and physiology (GAP) score (HR, 1.59, P=0.029) were strong predictors of mortality in never-smoking IPF patients at our hospital.

CONCLUSIONS

In conclusion, never-smoking IPF patients developed AE more often and showed poor prognosis compared with smoking IPF patients. The 1-year mMRC breathlessness scale was an important predictor of mortality at our hospital.

Combined pulmonary fibrosis and emphysema: The many aspects of a cohabitation contract

Combined pulmonary fibrosis and emphysema (CPFE) is a clinical entity characterized by the coexistence of upper lobe emphysema and lower lobe fibrosis. Patients with this condition experience severe dyspnea and impaired gas exchange with preserved lung volumes. The diagnosis of the CPFE syndrome is based on HRCT imaging, showing the coexistence of emphysema and pulmonary fibrosis both in varying extent and locations within the lung parenchyma. Individual genetic background seem to predispose to the development of the disease. The risk of the development of pulmonary hypertension in patients with CPFE is high and related to poor prognosis. CPFE patients also present a high risk of lung cancer. Mortality is significant in patients with CPFE and median survival is reported between 2.1 and 8.5 years. Currently, no specific recommendations are available regarding the management of patients with CPFE. In this review we provide information on the existing knowledge on CPFE regarding the pathophysiology, clinical manifestations, imaging, complications, possible therapeutic interventions and prognosis of the disease.

Managing comorbidities in idiopathic pulmonary fibrosis

Major risk factors for idiopathic pulmonary fibrosis (IPF) include older age and a history of smoking, which predispose to several pulmonary and extra-pulmonary diseases. IPF can be associated with additional comorbidities through other mechanisms as either a cause or a consequence of these diseases. We review the literature regarding the management of common pulmonary and extra-pulmonary comorbidities, including chronic obstructive pulmonary disease, lung cancer, pulmonary hypertension, venous thromboembolism, sleep-disordered breathing, gastroesophageal reflux disease, coronary artery disease, depression and anxiety, and deconditioning. Recent studies have provided some guidance on the management of these diseases in IPF; however, most treatment recommendations are extrapolated from studies of non-IPF patients. Additional studies are required to more accurately determine the clinical features of these comorbidities in patients with IPF and to evaluate conventional treatments and management strategies that are beneficial in non-IPF populations.

Visually stratified CT honeycombing as a survival predictor in combined pulmonary fibrosis and emphysema

OBJECTIVE

To determine whether visually stratified CT findings and pulmonary function variables are helpful in predicting mortality in patients with combined pulmonary fibrosis and emphysema (CPFE).

METHODS

We retrospectively identified 113 patients with CPFE who underwent high-resolution CT between January 2004 and December 2009. The extent of emphysema and fibrosis on CT was visually assessed using a 6- or 5-point scale, respectively. Univariate and multivariate Cox proportional regression analyses were performed to determine the prognostic value of visually stratified CT findings and pulmonary function variables in patients with CPFE. Differences in 5-year survival rates in patients with CPFE according to the extent of honeycombing were calculated using Kaplan-Meier analysis.

RESULTS

An increase in the extent of visually stratified honeycombing on CT [hazard ratio (HR), 1.95; p = 0.018; 95% confidence interval (CI), 1.12-3.39] and reduced diffusing capacity of lung for carbon monoxide (DLCO) (HR, 0.97; p = 0.017; 95% CI, 0.94-0.99) were independently associated with increased mortality. In patients with CPFE, the 5-year survival rate was 78.5% for <5% honeycombing, 55.7% for 5-25% honeycombing, 32% for 26-50% honeycombing and 33.3% for >50% honeycombing on CT.

CONCLUSION

The >50% honeycombing on CT and reduced DLCO are important prognostic factors in CPFE.

ADVANCES IN KNOWLEDGE

Visual estimation of honeycombing extent on CT can help in the prediction of prognosis in CPFE.

Acute exacerbation of idiopathic pulmonary fibrosis: shifting the paradigm

The goal of this review is to summarise the clinical features, management, and prognosis of acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF). AE-IPF has previously been defined based on clinical and radiological features that include the subacute onset of dyspnoea, bilateral ground glass changes on chest high-resolution computed tomography, and the absence of an identifiable aetiology. The annual incidence of AE-IPF is typically reported at 5–15%, but is less common in mild disease. Features of diffuse alveolar damage are present when a biopsy is performed. Idiopathic pulmonary fibrosis (IPF) patients with acute respiratory worsening are often initially treated with high dose corticosteroids and antimicrobials; however, there are no clear data to support these therapies, and the short-term mortality of AE-IPF is ∼50%. Recent studies have shown that the features and prognosis of AE-IPF are similar to other causes of acute respiratory worsening, including infection, aspiration, air pollution and mechanical injury to the alveolar epithelium. Based on this emerging evidence, we propose a novel approach to the classification of acute respiratory worsening events in patients with IPF that focuses on clinical and radiological findings consistent with an underlying pathobiology of diffuse alveolar damage.

Combined pulmonary fibrosis and emphysema (CPFE): an entity different from emphysema or pulmonary fibrosis alone

Chronic obstructive pulmonary disease (COPD) and idiopathic interstitial pneumonias (IIP), with different radiological, pathological, functional and prognostic characteristics, have been regarded as separate entities for a long time. However, there is an increasing recognition of the coexistence of emphysema and pulmonary fibrosis in individuals. The association was first described as a syndrome by Cottin in 2005, named "combined pulmonary fibrosis and emphysema (CPFE)", which is characterized by exertional dyspnea, upper-lobe emphysema and lower-lobe fibrosis, preserved lung volume and severely diminished capacity of gas exchange. CPFE is frequently complicated by pulmonary hypertension, acute lung injury and lung cancer and prognosis of it is poor. Treatments for CPFE patients with severe pulmonary hypertension are less effective other than lung transplantation. However, CPFE has not yet attracted wide attention of clinicians and there is no research systematically contrasting the differences among CPFE, emphysema/COPD and IIP at the same time. The authors will review the existing knowledge of CPFE and compare them to either entity alone for the first time, with the purpose of improving the awareness of this syndrome and exploring novel effective therapeutic strategies in clinical practice.

Combined pulmonary fibrosis and emphysema: an increasingly recognized condition

Combined pulmonary fibrosis and emphysema (CPFE) has been increasingly recognized in the literature. Patients with CPFE are usually heavy smokers or former smokers with concomitant lower lobe fibrosis and upper lobe emphysema on chest HRCT scans. They commonly present with severe breathlessness and low DLCO, despite spirometry showing relatively preserved lung volumes. Moderate to severe pulmonary arterial hypertension is common in such patients, who are also at an increased risk of developing lung cancer. Unfortunately, there is currently no effective treatment for CPFE. In this review, we discuss the current knowledge of the pathogenesis, clinical characteristics, and prognostic factors of CPFE. Given that most of the published data on CPFE are based on retrospective analysis, more studies are needed in order to address the role of emphysema and its subtypes; the progression of fibrosis/emphysema and its correlation with inflammation; treatment options; and prognosis.

[Acute on chronic respiratory failure in interstitial pneumonias]

BACKGROUND

Acute exacerbations of idiopathic interstitial pneumonias and exacerbations of pleuropulmonary disease in connective tissue diseases are associated with a high mortality.

DIAGNOSTIC PROCEDURES

They have to be differentiated from respiratory failure in patients with interstitial lung disease as a result of infections, pulmonary embolism, cardiac failure and drug toxicity, because the latter can be treated causally. The extent and the invasivity of diagnostic procedures have to be adopted to the patient's situation. A rapid diagnosis is important in order to initiate therapies (antibiotics, anticoagulation, immunosuppression) in treatable causes of exacerbations.

IMPORTANCE OF VENTILATION

The prognosis for patients who are under invasive mechanical ventilation in acute exacerbations of interstitial lung disease is poor. Especially in acute exacerbations of idiopathic pulmonary fibrosis (IPF), there is no general recommendation for either invasive or for noninvasive ventilation. In acute exacerbations of other subtypes of interstitial pneumonia, either idiopathic or as a pulmonary manifestation of connective tissue disease, and in all secondary exacerbations of idiopathic interstitial pneumonias which offer further treatment options, the decision about mechanical ventilation requires a differentiated assessment.

LUNG TRANSPLANTATION

In younger patients with interstitial lung disease and a progressive disease, indication for lung transplantation should be made early and before an exacerbation. If patients listed for lung transplantation experience an acute exacerbation, bridging-to-transplant has to be discussed with the transplant unit. In cases without further causal treatment options palliative care must be initiated.

Expression of aquaporins in bronchial tissue and lung parenchyma of patients with chronic obstructive pulmonary disease

Background

Aquaporins AQP1 and AQP5 are highly expressed in the lung. Recent studies have shown that the expression of these proteins may be mechanistically involved in the airway inflammation and in the pathogenesis of chronic obstructive pulmonary disease (COPD). The aim of this study was to investigate the expression of AQP1 and AQP5 in the bronchial tissue and the lung parenchyma of patients with COPD and COPD-resistant smokers.

Methods

Using a case–control design, we selected a group of 15 subjects with COPD and 15 resistant smokers (smokers without COPD) as a control, all of whom were undergoing lung resection surgery due to a lung neoplasm. We studied the expression of AQP1 and AQP5 in the bronchial tissue and the lung parenchyma by means of immunohistochemistry and reverse-transcription real-time polymerase chain reaction. Tissue expression of AQP1 and AQP5 was semi-quantitatively assessed in terms of intensity and expression by immunohistochemistry using a 4-point scale ranging from 0 (none) to 3 (maximum).

Results

There were no significant differences in gene expression between COPD patients and resistant smokers both in the bronchial tissue and in the lung parenchyma. However, AQP1 gene expression was 2.41-fold higher in the parenchyma of smokers with COPD compared to controls, whereas the AQP5 gene showed the opposite pattern, with a 7.75-fold higher expression in the bronchus of smokers with COPD compared with controls. AQP1 and AQP5 proteins were preferentially expressed in endothelial cells, showing a higher intensity for AQP1 (66.7% of cases with an intensity of 3, and 93.3% of subjects with an extension of 3 among patients with COPD). Subtle interstitial disease was associated with type II pneumocyte hyperplasia and an increased expression of AQP1.

Conclusions

This study provides pilot observations on the differences in AQP1 and AQP5 expression between COPD patients and COPD-resistant smokers. Our findings suggest a potential role for AQP1 in the pathogenesis of COPD.

A cohort study of mortality predictors in patients with acute exacerbation of chronic fibrosing interstitial pneumonia

OBJECTIVES

To assess clinical, laboratory and radiographic findings associated with outcomes and to clarify more practical ways to predict hospital mortality in patients with acute exacerbation (AE) of chronic fibrosing interstitial pneumonia (CFIP).

DESIGN

Single-centre retrospective cohort study.

SETTING

University Hospital in Japan.

PARTICIPANTS

We identified 51 consecutive patients with AE of idiopathic CFIP through multidisciplinary discussion. Patients who had connective tissue disease, drug-induced lung disease, pneumoconiosis, hypersensitivity pneumonitis, sarcoidosis, pulmonary histiocytosis, lymphangioleiomyomatosis and eosinophilic pneumonia were excluded.

INTERVENTIONS

There were no interventions.

MAIN OUTCOME MEASURES

The main outcome was determination of in-hospital mortality predictors. Other outcomes included clinical, laboratory and radiographic differences between non-survivors and survivors in patients with AE of CFIP.

RESULTS

The mean age of the patients with AE of CFIP was 71 years. Compared with survivors, non-survivors had a significantly shorter duration of symptoms before admission, lower prevalence of peripheral distribution of ground-glass opacity and centrilobular emphysema (CLE) on thin-section CT, lower peripheral lymphocyte count, higher brain natriuretic peptide titre, lower Pao2:Fio2 (P:F) ratio, higher prevalence of systemic inflammatory response syndrome (SIRS) and higher SIRS score on admission (p=0.0069, 0.0032, 0.015, 0.040, 0.0098, 0.012, 9.9×10(-7) and 5.4×10(-6), respectively). Multivariate analysis revealed SIRS (HR=6.2810, p=0.015), CLE (HR=0.0606, p=3.6×10(-5)) and serum procalcitonin level (HR=2.7110, p=0.022) to be independent predictors of in-hospital mortality. A Kaplan-Meier estimate on the basis of stratification according to the presence or absence of SIRS and CLE demonstrated a distinct survival curve for each subset of patients.

CONCLUSIONS

Distinct survival curves documented by stratification according to the presence or absence of SIRS and CLE may provide basic information for a rational management strategy for patients with AE of CFIP on admission.

Combined pulmonary fibrosis and emphysema

The advent of computed tomography permitted recognition of the coexistence of pulmonary fibrosis and emphysema (CPFE). Emphysema is usually encountered in the upper lobes preceding fibrosis of the lower lobes, and patients are smokers, predominantly male, with distinct physiologic profile characterized by preserved lung volumes and markedly reduced diffusion capacity. Actually, the term CPFE is reserved for the coexistence of any type and grade of radiological pulmonary emphysema and the idiopathic usual interstitial pneumonia computed tomography pattern as well as any pathologically confirmed case. CPFE is complicated by pulmonary hypertension, lung cancer and acute lung injury and may present different outcome than that of its components.

Annual changes in pulmonary function in combined pulmonary fibrosis and emphysema: over a 5-year follow-up

BACKGROUND

Combined pulmonary fibrosis and emphysema (CPFE) is a unique disorder that has been previously described, and the distinct features of CPFE in comparison with chronic obstructive pulmonary disease (COPD) have been reported. However, the yearly dynamics of pulmonary function parameters in CPFE patients compared with those in COPD patients have not yet been reported.

METHODS

We retrospectively enrolled patients with CPFE and COPD who had undergone pulmonary function tests more than five times during a follow-up period of more than five years. The baseline clinical characteristics and the annual changes in pulmonary function during the follow-up period in 16 stable CPFE patients were compared with those in 19 stable COPD patients. Annual changes in pulmonary function were estimated from linear regressions, with assumptions for time-dependency and linearity. We analyzed the time-dependent fluctuations in pulmonary function for the two disorders.

RESULTS

Annual decreases in VC and FVC in the CPFE group were significantly higher than those in the COPD group. Annual decrease in FEV1/FVC in the COPD group was significantly higher than in the CPFE group. During the follow-up period, FEV1/FVC in the CPFE group appeared to improve because of annual decrease in FVC. Annual decreases in DLco and DLco/VA in the CPFE group were significantly higher than those in the COPD group.

CONCLUSION

This is the first report showing the yearly dynamics of pulmonary function parameters in CPFE patients compared with those in COPD patients during a follow-up period of more than five years. This study revealed that the physiologic consequences of CPFE including the rate of progression of pulmonary function impairment were different from those of COPD.

Combined pulmonary fibrosis and emphysema in connective tissue disease

PURPOSE OF REVIEW

This review discusses combined pulmonary fibrosis and emphysema (CPFE) in the setting of connective tissue disease.

RECENT FINDINGS

CPFE is a recently identified syndrome in smokers or ex-smokers characterized by dyspnea often severe, preserved lung volumes, severely impaired gas exchanges, and an increased risk of pulmonary hypertension associated with a dismal prognosis, and possibly lung cancer. It may be encountered in the setting of connective tissue diseases, especially rheumatoid arthritis and systemic sclerosis, with generally similar features as 'idiopathic' (tobacco-related) CPFE. The diagnosis is based on the presence of both emphysema predominating in the upper lobes and frequently paraseptal, and interstitial abnormalities suggesting pulmonary fibrosis in the lower lung zones with velcro crackles at auscultation. Pathologic radiological correlations are difficult owing to various pathology and difficulties in identifying honeycombing at chest high-resolution computed tomography in the setting of coexistent emphysema. Tobacco smoking is associated with an increased risk of developing most of the individual components of the syndrome (i.e. emphysema, pulmonary fibrosis, pulmonary hypertension, rheumatoid arthritis, and pulmonary fibrosis among patients with rheumatoid arthritis). CPFE impacts modalities of follow-up for pulmonary function and detection of pulmonary hypertension especially in systemic sclerosis.

SUMMARY

The syndrome of CPFE is a distinct pulmonary manifestation in the spectrum of lung diseases associated with connective tissue diseases, especially in smokers or ex-smokers.