Pulmonary Rehabilitation in Patients with Interstitial Lung Disease. Experience in a Specialized Hospital in Argentina / Rehabilitación respiratoria en pacientes con enfermedad pulmonar intersticial difusa. Experiencia de un hospital especializado de Argentina

Introduction: Interstitial lung diseases generate in patients exercise intolerance, dyspnea, and a decrease in health-related quality of life. Pulmonary Rehabilitation plays an important role in the treatment of these patients. Materials and Methods: We conducted a retrospective study in a cohort of patients with interstitial lung disease (DILD) who underwent Pulmonary Rehabilitation (PR) between 2012 and 2015. Patients completed a 4-month treatment program including aerobic, core, and upper and lower limbs strength training and health education. Quality of life was measured with the St. George´s Respiratory Questionnaire (SGRQ), and exercise tolerance with the 6-minute walk test (6MWT) pre- and post-PR. Results were compared among patients with idiopathic pulmonary fibrosis (IPF) and other ILDs. Results: 93 patients were included (46 male); 42 (44.09%) completed the program. After the PR, the SGRQ mean score decreased by 8.7 (95% CI [confidence interval]: 2.85-14.42), with no differences between the IPF and other diagnoses. The results of the 6MWT showed mean improvement of 14.07 m, not reaching statistical significance (p = 0.132). The subgroup of patients who walked less than 400 m (n = 18) showed clinical and statistically significant improvement (40.8 m; p = 0.025). We didn't find differences in this test in terms of diagnosis. Conclusions: PR in this cohort of patients with ILD showed improvement in quality of life and exercise tolerance, with no differences regarding the specific diagnosis.

Diagnostic Approaches to Diffuse Interstitial Lung Diseases

Diffuse interstitial lung diseases (DILDs) are a heterogeneous group of non-neoplastic, noninfectious disorders resulting from damage to the lung parenchyma, and present with similar clinical features. There has been difficulty in the classification and diagnosis of DILDs because they contain more than 200 diseases. The American Thoracic Society and European Respiratory Society (ATS/ERS) expert meeting have proposed to classify DILDs into 4 categories, (1) known cases, (2) granulomatous diseases, (3) idiopathic interstitial pneumonias (IIPs), and (4) other forms. Among them, IIPs also comprise several different clinicopathological entities; however, it was previously thought to be a single disease, idiopathic pulmonary fibrosis (IPF), and resulted in a lot of confusion. Therefore, the ATS/ERS consensus classification provided a standardized nomenclature and diagnostic criteria of IIPs. IIPs are now classified into seven clinicopathologic entities; IPF, nonspecific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia (COP), acute interstitial pneumonia (AIP), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), desquamative interstitial pneumonia (DIP), and lymphoid interstitial pneumonia (LIP). Because of these complexities, it is not easy to make the diagnosis of the patients with DILDs. This review will present a brief overview of DILDs and summary of diagnostic approaches with highlights on several specific items. An important thing to emphasize is the diagnosis of DILDs should be multi-disciplinary and the final diagnosis should be rendered only after reviewing all of the clinical, radiological, and pathological data of the patient. The more detailed description and discussion on some common diseases of DILDs will be followed by different authors.

Feasibility of Automated Quantification of Regional Disease Patterns Depicted on High-Resolution Computed Tomography in Patients with Various Diffuse Lung Diseases

OBJECTIVE: This study was designed to develop an automated system for quantification of various regional disease patterns of diffuse lung diseases as depicted on high-resolution computed tomography (HRCT) and to compare the performance of the automated system with human readers. MATERIALS AND METHODS: A total of 600 circular regions-of-interest (ROIs), 10 pixels in diameter, were utilized. The 600 ROIs comprised 100 ROIs that represented six typical regional patterns (normal, ground-glass opacity, reticular opacity, honeycombing, emphysema, and consolidation). The ROIs were used to train the automated classification system based on the use of a Support Vector Machine classifier and 37 features of texture and shape. The performance of the classification system was tested with a 5-fold cross-validation method. An automated quantification system was developed with a moving ROI in the lung area, which helped classify each pixel into six categories. A total of 92 HRCT images obtained from patients with different diseases were used to validate the quantification system. Two radiologists independently classified lung areas of the same CT images into six patterns using the manual drawing function of dedicated software. Agreement between the automated system and the readers and between the two individual readers was assessed. RESULTS: The overall accuracy of the system to classify each disease pattern based on the typical ROIs was 89%. When the quantification results were examined, the average agreement between the system and each radiologist was 52% and 49%, respectively. The agreement between the two radiologists was 67%. CONCLUSION: An automated quantification system for various regional patterns of diffuse interstitial lung diseases can be used for objective and reproducible assessment of disease severity.

Radiologic Diagnosis of Interstitial Lung Diseases

Diffuse interstitial lung diseases (DILD) are a group of chronic disorders showing varying degrees of active inflammation and established fibrosis mainly involving the interstitium of the lungs. DILD can be classified into two groups in an etiologic aspect; idiopathic and DILD with known-cause, such as connective tissue diseases associated with DILD. Although there had been complexity and variability in the classification of idiopathic interstitial pneumonia (IIP), an international standard was established for the classification of IIPs including seven clinicalradiologic-pathologic entities; idiopathic pulmonary fibrosis (IPF), nonspecific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia (COP), acute interstitial pneumonia (AIP), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), desquamative interstitial pneumonia (DIP), and lymphoid interstitial pneumonia (LIP). The prognosis of fibrotic NSIP and IPF is much poorer compared to those of other spectrum of IIPs, such as COP, RB-ILD, DIP, and LIP. Therefore, fibrotic NSIP and IPF can be considered separately as a group of fibrotic IIPs. Trying to predict the prognosis of IIPs, there has been an effort to differentiate inflammationpredominant lesions from fibrosis-predominant lesions in patients with fibrotic IIPs. Radiologic features of low fibrotic scores at high-resolution CT and early enhancement patterns at dynamic enhancement of MRI can be useful prognostic determinants for the prediction of disease improvement in patients with fibrotic IIPs.

Plasma and Urine Endothelin Concentrations in Patients with Diffuse Interstitial Lung Disease / 결핵

BACKGROUND: Endothelin(ET), a potent vasoconstrictor peptide produced by endothelial cells and degraded predominantly in the pulmonary vasculature, have been implicated in the development of various organ dysfunctions. Plasma concentrations of ET-1 are reported to be elevated in patients with diffuse interstitial lung disease(DILD). But, there is no study to establish the exact source and mechanisms involved in the increased plasma ET-1 concentrations in DILD patients. METHODS: 12 patients with IPF, 2 patients with sarcoidosis, 2 patients with scleroderma, 1 patient with SLE and 11 healthy volunteers were studied. ET was detected by radioimmunoassay in plasma and bronchoalveolar lavage fluid(BALF) as well as in 24-hr urine specimens. For each subjects, arterial/venous(A7V) ET ratio and renal ET clearance were calculated. RESULTS: Elevated plasma, urine and BALF ET concentrations were found in patients with DILD compared with controls. But, no significant difference was observed in ET A/V ratio and ET renal clearance between patients with DILD and controls. CONCLUSION: We observed that plasma ET concentrations were elevated in patients with DILD, and that the main site of ET production may be lung parenchyme.

The Role of Open Lung Biopsy in Diagnosis and Treatment of Diffuse Interstitial Lung Disease in High-resolution Computed Tomography Era / 결핵

Objective: Diffuse interstitial lung disease (DILD) is a group of diverse diseases that share common clinical, radiologic, and pulomonary function features. Open lung biopsy (OLB) has been regarded as gold standard in differential diagnosis of DILD. However open lung biopsy is a invasive diagnostic tool not free of its own risk or complications. These days, high-resolution computed tomography (HRCT) has become an important diagnostic tool in DILD through its precise image analysis. In many instances, HRCT could provide specific diagnosis or, at least, provide information on the disease activity of DILD. The authors re-evaluate the role of open lung biopsy in this "HRCT era" by investigating the additional diagnostic gain and impacts on the treatment plan in patients who have undergone high-resoluticm CT. Method: Diagnoses obtained by high-resolution CT and open lung biopsy were compared and changes of treatment plans were evaluated retrospectively in 30 patients who had undergone open lung biopsy for the purpose of diagnosis of diffuse interstitial lung disease from March 1988 to June 1994. Results: High-resolution CT suggeted specific diagnoses in 22 out of 28 patients (78.6%) and the diagnoses were confirmed to be correct by open lung biopy in 20 of those 22 cases (91%). Open lung biopsy could not give specific diagnosis in 5 out of 30 cases (16.7%). In 5 out of 6 cases (83.3%) in whom high reolution CT was not able to suggest specific diagnosis, open lung biopsy gave specific diagnoses. Treatment plan was altered by the result of open lung biopsy in only 2 cases. Conclusion: The above findings suggest that in "HRCT era", when HRCT could suggest specific diagnosis, the need for open lung biopsy should be re-evaluated.

The Role of Open Lung Biopsy in Diagnosis and Treatment of Diffuse Interstitial Lung Disease in High-resolution Computed Tomography Era / 결핵

Objective: Diffuse interstitial lung disease (DILD) is a group of diverse diseases that share common clinical, radiologic, and pulomonary function features. Open lung biopsy (OLB) has been regarded as gold standard in differential diagnosis of DILD. However open lung biopsy is a invasive diagnostic tool not free of its own risk or complications. These days, high-resolution computed tomography (HRCT) has become an important diagnostic tool in DILD through its precise image analysis. In many instances, HRCT could provide specific diagnosis or, at least, provide information on the disease activity of DILD. The authors re-evaluate the role of open lung biopsy in this "HRCT era" by investigating the additional diagnostic gain and impacts on the treatment plan in patients who have undergone high-resoluticm CT. Method: Diagnoses obtained by high-resolution CT and open lung biopsy were compared and changes of treatment plans were evaluated retrospectively in 30 patients who had undergone open lung biopsy for the purpose of diagnosis of diffuse interstitial lung disease from March 1988 to June 1994. Results: High-resolution CT suggeted specific diagnoses in 22 out of 28 patients (78.6%) and the diagnoses were confirmed to be correct by open lung biopy in 20 of those 22 cases (91%). Open lung biopsy could not give specific diagnosis in 5 out of 30 cases (16.7%). In 5 out of 6 cases (83.3%) in whom high reolution CT was not able to suggest specific diagnosis, open lung biopsy gave specific diagnoses. Treatment plan was altered by the result of open lung biopsy in only 2 cases. Conclusion: The above findings suggest that in "HRCT era", when HRCT could suggest specific diagnosis, the need for open lung biopsy should be re-evaluated.

A Histologic Classification of Diffuse Interstitial Lung Disease and Its Clinical Significance

Diffuse interstitial lung disease(DILD) is a large group of heterogeneous diseases that diffusely involve the pulmonary connective tissues, principally subpleural, interlobular and alveolar wall portions. Terminology and classification of these diseases are not uniform, and the cause and the pathogenesis are unknown in many entities. It is generally accepted that the response to therapy is related to the relative degree of cellularity and fibrosis present, therefore a histologic evaluation of the relative extent and severity of these changes is required. We reviewed 52 cases of DILD from January 1990 to May 1995 diagnosed by open lung biopsy to reappraise classification and quantitative assessment of the histopathologic features. Differential histopathologic features between usual interstitial pneumonia(UIP) and nonspecific interstitial pneumonia(NIP) were examined with a correlation of HRCT findings and clinical findings. Among 52 cases of DILD, 18 cases(34.6%) were UIP, 6 cases(11.5%) were hypersensitivity pneumonia was NIP was 5 cases(9.6%), interstitial lung diseases associated with the connective tissue diseases were 5 cases(9.6%), inorganic dusts were 4 cases(7.7%), infections were 4 cases(7.7%), durgs were 2 cases(3.8%), acute interstitial pneumonia was 1 case(1.9%), sarcoidosis was 1 case(1.9%) in order of frequency plus 6 other cases(11.5%). UIP was the most frequent DILD in this study which seemed to be a criteria bias of patient selection on open lung biopsy. Quantitative assessment of histopathologic features was useful in the differential diagnosis of DILD and differentiation of UIP from NIP was possible based on histopathologic features and supported by HRCT. UIP disclosed a significantly high score of fibrotic changes, especially in the interstitial fibrosis, smooth muscle proliferation and honeycombing, otherwise NIP appeared relatively high score in inflammatory changes. Correlation between histopathologic scores and the clinical outcome after steroid therapy or no therapy in UIP was not evident.