Diagnosis Of Usual Interstitial Pneumonia Research Articles

Deep Learning Classification of Usual Interstitial Pneumonia Predicts Outcomes.

Rationale: Computed tomography (CT) enables noninvasive diagnosis of usual interstitial pneumonia (UIP), but enhanced image analyses are needed to overcome the limitations of visual assessment. Objectives: Apply multiple instance learning (MIL) to develop an explainable deep learning algorithm for prediction of UIP from CT and validate its performance in independent cohorts. Methods: We trained an MIL algorithm using a pooled dataset (n = 2,143) and tested it in three independent populations: data from a prior publication (n = 127), a single-institution clinical cohort (n = 239), and a national registry of patients with pulmonary fibrosis (n = 979). We tested UIP classification performance using receiver operating characteristic analysis, with histologic UIP as ground truth. Cox proportional hazards and linear mixed-effects models were used to examine associations between MIL predictions and survival or longitudinal FVC. Measurements and Main Results: In two cohorts with biopsy data, MIL improved accuracy for histologic UIP (area under the curve, 0.77 [n = 127] and 0.79 [n = 239]) compared with visual assessment (area under the curve, 0.65 and 0.71). In cohorts with survival data, MIL-UIP classifications were significant for mortality (n = 239, mortality to April 2021: unadjusted hazard ratio, 3.1; 95% confidence interval [CI], 1.96-4.91; P < 0.001; and n = 979, mortality to July 2022: unadjusted hazard ratio, 3.64; 95% CI, 2.66-4.97; P < 0.001). Individuals classified as UIP positive by the algorithm had a significantly greater annual decline in FVC than those classified as UIP negative (-88 ml/yr vs. -45 ml/yr; n = 979; P < 0.01), adjusting for extent of lung fibrosis. Conclusions: Computerized assessment using MIL identifies clinically significant features of UIP on CT. Such a method could improve confidence in radiologic assessment of patients with interstitial lung disease, potentially enabling earlier and more precise diagnosis.

Pulmonary Pathology Society Survey on Practice Approaches in the Histologic Diagnosis of Fibrotic Interstitial Lung Disease: Consensus and Opportunities.

The pathologic diagnosis of usual interstitial pneumonia (UIP) remains a challenging area, and application of histologic UIP guidelines has proved difficult. To understand current practice approaches by pulmonary pathologists for the histologic diagnosis of UIP and other fibrotic interstitial lung diseases (ILDs). The Pulmonary Pathology Society (PPS) ILD Working Group developed and sent a 5-part survey on fibrotic ILD electronically to the PPS membership. One hundred sixty-one completed surveys were analyzed. Of the respondents, 89% reported using published histologic features in clinical guidelines for idiopathic pulmonary fibrosis (IPF) in their pathologic diagnosis; however, there was variability in reporting terminology, quantity and quality of histologic features, and the use of guideline categorization. Respondents were very likely to have access to pulmonary pathology colleagues (79%), pulmonologists (98%), and radiologists (94%) to discuss cases. Half of respondents reported they may alter their pathologic diagnosis based on additional clinical and radiologic history if it is pertinent. Airway-centered fibrosis, granulomas, and types of inflammatory infiltrates were considered important, but there was poor agreement on how these features are defined. There is significant consensus among the PPS membership on the importance of histologic guidelines/features of UIP. There are unmet needs for (1) consensus and standardization of diagnostic terminology and incorporation of recommended histopathologic categories from the clinical IPF guidelines into pathology reports, (2) agreement on how to incorporate into the report relevant clinical and radiographic information, and (3) defining the quantity and quality of features needed to suggest alternative diagnoses.

DYSKERATOSIS CONGENITA: A RARE CAUSE OF USUAL INTERSTITIAL PNEUMONIA

DYSKERATOSIS CONGENITA: A RARE CAUSE OF USUAL INTERSTITIAL PNEUMONIA

POSITIVE ENVISIA GENOMIC CLASSIFIER RESULT PREDICTS CLINICAL PROGRESSION IN FIBROTIC INTERSTITIAL LUNG DISEASE

POSITIVE ENVISIA GENOMIC CLASSIFIER RESULT PREDICTS CLINICAL PROGRESSION IN FIBROTIC INTERSTITIAL LUNG DISEASE

MIXTURE of human expertise and deep learning—developing an explainable model for predicting pathological diagnosis and survival in patients with interstitial lung disease

AbstractInterstitial pneumonia is a heterogeneous disease with a progressive course and poor prognosis, at times even worse than those in the main cancer types. Histopathological examination is crucial for its diagnosis and estimation of prognosis. However, the evaluation strongly depends on the experience of pathologists, and the reproducibility of diagnosis is low. Herein, we propose MIXTURE (huMan-In-the-loop eXplainable artificial intelligence Through the Use of REcurrent training), an original method to develop deep learning models for extracting pathologically significant findings based on an expert pathologist's perspective with a small annotation effort. The procedure of MIXTURE consists of three steps as follows. First, we created feature extractors for tiles from whole slide images using self-supervised learning. The similar looking tiles were clustered based on the output features and then pathologists integrated the pathologically synonymous clusters. Using the integrated clusters as labeled data, deep learning models to classify the tiles into pathological findings were created by transfer-learning the feature extractors. We developed three models for different magnifications. Using these extracted findings, our model was able to predict the diagnosis of usual interstitial pneumonia, a finding suggestive of progressive disease, with high accuracy (AUC 0.90 in validation set and AUC 0.86 in test set). This high accuracy could not be achieved without the integration of findings by pathologists. The patients predicted as UIP had poorer prognosis (5-year overall survival [OS]: 55.4%) than those predicted as non-UIP (OS: 95.2%). The Cox proportional hazards model for each microscopic finding and prognosis pointed out dense fibrosis, fibroblastic foci, elastosis, and lymphocyte aggregation as independent risk factors. We suggest that MIXTURE may serve as a model approach to different diseases evaluated by medical imaging, including pathology and radiology, and be the prototype for explainable artificial intelligence that can collaborate with humans.

Estimating the Clinical Impact of Photon-Counting-Detector CT in Diagnosing Usual Interstitial Pneumonia.

The aim of this study was to evaluate the clinical impact of a higher spatial resolution, full field-of-view investigational photon-counting detector computed tomography (PCD-CT) on radiologist confidence in imaging findings and diagnosis of usual interstitial pneumonia (UIP) compared with conventional energy-integrating detector CT (EID-CT). Patients suspected of interstitial lung disease were scanned on a PCD-CT system after informed consent and a clinically indicated EID-CT. In 2 sessions, 3 thoracic radiologists blinded to clinical history and scanner type evaluated CT images of the right and left lungs separately on EID- or PCD-CT, reviewing each lung once/session, rating confidence in imaging findings of reticulation, traction bronchiectasis, honeycombing, ground-glass opacities (GGOs), mosaic pattern, and lower lobe predominance (100-point scale: 0-33, likely absent; 34-66, indeterminate; 67-100, likely present). Radiologists also rated confidence for the probability of UIP (0-20, normal; 21-40, inconsistent with UIP; 41-60, indeterminate UIP; 61-81; probable UIP; 81-100, definite UIP) and graded image quality. Because a confidence scale of 50 represented completely equivocal findings, magnitude score (the absolute value of confidence scores from 50) was used for analysis (higher scores were more confident). Image noise was measured for each modality. The magnitude score was compared using linear mixed effects regression. The consistency of findings and diagnosis between 2 scanners were evaluated using McNemar test and weighted κ statistics, respectively. A total of 30 patients (mean age, 68.8 ± 11.0 years; M:F = 18:12) underwent conventional EID-CT (median CTDI vol , 7.88 mGy) and research PCD-CT (median CTDI vol , 6.49 mGy). The magnitude scores in PCD-CT were significantly higher than EID-CT for imaging findings of reticulation (40.7 vs 38.3; P = 0.023), GGO (34.4 vs 31.7; P = 0.019), and mosaic pattern (38.6 vs 35.9; P = 0.013), but not for other imaging findings ( P ≥ 0.130) or confidence in UIP (34.1 vs 22.2; P &lt; 0.059). Magnitude score of probability of UIP in PCD-CT was significantly higher than EID-CT in one reader (26.0 vs 21.5; P = 0.009). Photon-counting detector CT demonstrated a decreased number of indeterminate GGO (17 vs 26), an increased number of unlikely GGO (74 vs 50), and an increased number of likely reticulations (140 vs 130) relative to EID-CT. Interobserver agreements among 3 readers for imaging findings and probability of UIP were similar between PCD-CT and EID-CT (intraclass coefficient: 0.507-0.818 vs 0.601-0.848). Photon-counting detector CT had higher scores in overall image quality (4.84 ± 0.38) than those in EID-CT (4.02 ± 0.40; P &lt; 0.001) despite increased image noise (mean 85.5 vs 36.1 HU). Photon-counting detector CT provided better image quality and improved the reader confidence for presence or absence of imaging findings of reticulation, GGO, and mosaic pattern with idiosyncratic improvement in confidence in UIP presence.

A Handcrafted Radiomics-Based Model for the Diagnosis of Usual Interstitial Pneumonia in Patients with Idiopathic Pulmonary Fibrosis.

The most common idiopathic interstitial lung disease (ILD) is idiopathic pulmonary fibrosis (IPF). It can be identified by the presence of usual interstitial pneumonia (UIP) via high-resolution computed tomography (HRCT) or with the use of a lung biopsy. We hypothesized that a CT-based approach using handcrafted radiomics might be able to identify IPF patients with a radiological or histological UIP pattern from those with an ILD or normal lungs. A total of 328 patients from one center and two databases participated in this study. Each participant had their lungs automatically contoured and sectorized. The best radiomic features were selected for the random forest classifier and performance was assessed using the area under the receiver operator characteristics curve (AUC). A significant difference in the volume of the trachea was seen between a normal state, IPF, and non-IPF ILD. Between normal and fibrotic lungs, the AUC of the classification model was 1.0 in validation. When classifying between IPF with a typical HRCT UIP pattern and non-IPF ILD the AUC was 0.96 in validation. When classifying between IPF with UIP (radiological or biopsy-proved) and non-IPF ILD, an AUC of 0.66 was achieved in the testing dataset. Classification between normal, IPF/UIP, and other ILDs using radiomics could help discriminate between different types of ILDs via HRCT, which are hardly recognizable with visual assessments. Radiomic features could become a valuable tool for computer-aided decision-making in imaging, and reduce the need for unnecessary biopsies.

Morbidity and mortality of surgical lung biopsy in the diagnosis of usual interstitial pneumonia.

Histology represents the major source of information to define a usual interstitial pneumonia (UIP) pattern. However, the procedure is associated with significant morbidity and mortality. The aim of this study was to evaluate morbidity and mortality of surgical lung biopsy (SLB) in diagnosing UIP. Patients undergoing SLB with the ultimate diagnosis of UIP were studied. Clinical data concerning medical history, histology, pulmonary functions, radiology, length of hospital stay (LOS), morbidity and mortality status were retrospectively recruited from four hospitals. The study included consecutive 93 patients with a SLB diagnosis of UIP. Mean age was 61 ± 8 years, with one third of the patients were ≥65 years. In 58 cases (62.4%), the biopsy was performed by video-assisted thoracoscopic surgery, in 35 (37.7%) by limited thoracotomy. Eighty patients (86%) had possible UIP, 12 (12.9%) had inconsistent with UIP and one (1.1%) had UIP pattern on high-resolution computed tomography. The mean LOS was 5.47 ± 3.16 days. LOS was associated with smoking status (P = 0.024), type of biopsy (P = 0.00), 6-min walk test (P = 0.00) and number of biopsy (P = 0.00). There was no in-hospital and 30-day mortality in our cohort, and 90-day mortality rate was 1.1%. In seven patients (7.5%), we observed postoperative morbidities, predominantly prolonged air leakage (7.5% of all cases). Postoperative morbidity was only associated with the type of SLB. Patients with limited thoracotomy showed greater morbidity rates (17.1% versus 1.7%, P = 0.011). SLB is a relatively safe procedure in the diagnosis of UIP and can be performed in suitable patients with suspected UIP/idiopathic pulmonary fibrosis.

COMPARISON OF PRE- VS POST-LUNG TRANSPLANT CAUSE OF INTERSTITIAL LUNG DISEASE

SESSION TITLE: Transplantation Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: The aim of this study is to compare the clinical diagnosis of interstitial lung disease to that determined on post-explant evaluation. METHODS: Retrospective study conducted through chart review of 50 consecutive lung transplants performed in patients with interstitial lung disease (ILD) at The University of Health Sciences Center at San Antonio. All charts of patients over 18 years of age who underwent lung transplantation with the diagnosis of ILD were carefully reviewed to determine the clinical pre-transplant diagnosis. Studies included high-resolution computed tomography (HRCT), serologic evaluation of connective tissue disease in all patients. Data from transbronchial biopsy or open lung biopsy were reviewed in determining the pre-transplant diagnosis. We compared the pre-lung transplant diagnosis to the post-transplant, pathologic diagnosis determined from the explanted lungs. RESULTS: A total of 50 patients with ILD who had either single or bilateral lung transplant were analyzed. Thirty-three patients (66%) had pre-transplant (pre-tx) diagnosis of usual interstitial pneumonia (UIP), eight patients (16%) had pre-tx diagnosis of nonspecific interstitial pneumonia (NSIP), six patients (12%) had a pre-tx diagnosis of connective tissue disease – ILD (CTD-ILD), one patient (2%) with pre-tx diagnosis of hypersensitivity pneumonitis (HSP) while four patients (8%) had other diagnoses, including indeterminate end stage lung disease (ESLD), type I congenital cystic adenomatoid malformation (CCAM) and constrictive bronchiolitis with fibrosis. After lung explant biopsies were reviewed, seventeen (34%) cases were reclassified compared to the pre-tx diagnoses. However, out of these seventeen cases, only six cases (12%) were clinically significant. Out of the six clinically significant misdiagnoses, three had a final diagnosis of HSP and three had a final diagnosis of NSIP. The remaining discrepancies in diagnosis were disorders t hat are known to progress to UIP. CONCLUSIONS: Almost two-thirds (66%) of all cases had consistent pre-transplant diagnoses when compared to post- transplant diagnoses. Most of the remaining cases (22%) had disorders known to progress to UIP. However, in 12% of cases, the diagnosis changed from a disorder with a progressive course to one that carries a different prognosis and might have responded to alternative therapies (NSIP and HSP). CLINICAL IMPLICATIONS: Definitive diagnosis in patients with ILD is both difficult and challenging. However, it is imperative to be cautious and observant when searching for disorders that are more responsive to environmental changes or responsive to immunotherapy. Early diagnosis of accurate ILD along with the use of multi-disciplinary discussion (MDD) can improve appropriate therapy in patients with ILD. DISCLOSURES: No relevant relationships by Sarah Hackman, source=Web Response No relevant relationships by Tasnim Islam, source=Web Response No relevant relationships by Jay Peters, source=Web Response

Comparison of Clinical Measures Among Interstitial Lung Disease (ILD) Patients with Usual Interstitial Pneumonia (UIP) Patterns on High-Resolution Computed Tomography.

Idiopathic Pulmonary Fibrosis is a progressive and fatal interstitial lung disease (ILD) characterized by a typical radiographic or histologic usual interstitial pneumonia (UIP) pattern.In 2018, diagnostic categories of UIP based on computed tomography patterns were revised by the Fleischner Society. The study aimed to describe differences in comorbidities and spirometry in ILD patients that were characterized by high-resolution computed tomography (HRCT) images as having a typical, probable, indeterminate, and alternative diagnosis of UIP. We retrospectively studied 80 ILD patients from 2017 to 2019. Typical UIP was defined using the Fleischner Society diagnostic criteria for IPF. Atypical UIP was reached by consensus after a multidisciplinary clinical-radiological-pathological review of patient data. Baseline characteristics, comorbidities, and spirometry were compared among the four subgroups. Among 80 patients, 59% were male, 61% had a history of smoking, and the mean age was 67.7 ± 10years (SD). A typical UIP pattern was more frequently observed among patients with chronic obstructive pulmonary disease (COPD) (p < 0.001) and pulmonary hypertension (p = 0.03). Of 30 patients with COPD, 14 had emphysema, while 10 had IPF. After adjusting for forced expiratory volume in one second (FEV1) in liters, change of FEV1% from baseline to 6-12months, age, and sex, only COPD remained significantly associated with typical UIP (p = 0.018). Tobacco use was not significantly associated with any radiographic type (p = 0.199). Typical UIP was prevalent among COPD/emphysema patients. Although smoking has a strong association with IPF, we did not find a significant association with smoking and typical UIP in our cohort.

Radiological pitfalls associated with the diagnosis of usual interstitial pneumonia pattern on high-resolution computed tomography and associated findings: experience from a single Italian center.

The diagnostic algorithm for idiopathic pulmonary fibrosis (IPF) based on high-resolution computed tomography (HRCT) findings and multidisciplinary discussion (MDD) has been well established. To identify the causes of disagreement between non-thoracic and thoracic radiologist involved in MDD for the imaging diagnosis of usual interstitial pneumonia (UIP) patterns and associated findings on HRCT and to improve the understanding of IPF by non-expert radiologists through a more systematic approach to HRCT. This study included 68 patients who underwent MDD for suspected IPF. We compared the first reports generated before MDD by non-expert radiologists with the CT pattern and associated findings of IPF reported by thoracic radiologist involved in MDD. Regarding the diagnosis of CT pattern by non-expert radiologists, 30/68 patients received a discordant diagnosis, and in another 28 reports, all features of the CT pattern were described without reaching a diagnostic conclusion. The first report was concordant in only 10 patients. For 63 cases in which associated findings were reported by expert radiologists in MDD, we documented discrepancies in 47 cases where associated findings were considered absent by the first non-thoracic radiologist. We found significant discrepancies in the imaging diagnosis of UIP patterns and associated findings on HRCT between non-expert and thoracic radiologists included in MDD. Therefore, in this study, we analyzed and suggested diagnostic strategies to improve non-expert radiologists' approach to HRCT.

Centrilobular Fibrosis in Fibrotic (Chronic) Hypersensitivity Pneumonitis, Usual Interstitial Pneumonia, and Connective Tissue Disease-Associated Interstitial Lung Disease.

Various pulmonary diseases can produce centrilobular (peribronchiolar) fibrosis, which may be isolated or associated with other patterns of more diffuse fibrosis. The major forms of interstitial lung disease in which centrilobular fibrosis is found are fibrotic (chronic) hypersensitivity pneumonitis, connective tissue disease-associated interstitial lung disease, and (a disputed issue) usual interstitial pneumonia/idiopathic interstitial fibrosis. To review recent literature that addresses separation of these entities. Data comprised recent publications. In a specially constructed multidisciplinary discussion exercise, it was found that peribronchiolar metaplasia affecting more than half the bronchioles or more than 2 foci of peribronchiolar metaplasia per square centimeter of biopsy area was strongly associated with a confident diagnosis of fibrotic hypersensitivity pneumonitis. Giant cells or granulomas were only found in cases with a greater than 50% diagnostic confidence in hypersensitivity pneumonitis. Conversely, greater numbers of fibroblast foci per square centimeter and increasing measured amounts of subpleural fibrosis favored a diagnosis of usual interstitial pneumonia. Recent data also suggest that centrilobular fibrosis can be found in usual interstitial pneumonia, although the presence of centrilobular fibrosis statistically favors an alternate diagnosis. Connective tissue disease is a major confounder because many patterns are very similar to fibrotic hypersensitivity pneumonitis or usual interstitial pneumonia. Genetic abnormalities, such as the MUC5B minor allele overlap, in these conditions and at this point cannot be used for discrimination. Thus, the separation of fibrotic hypersensitivity pneumonitis and usual interstitial pneumonia remains a difficult problem. Accurate biopsy diagnosis of all of these diseases requires correlation with imaging and clinical findings, and is crucial for treatment.

Detection of the usual interstitial pneumonia pattern in chest CT: effect of computer-aided diagnosis on radiologist diagnostic performance.

Anti-fibrotic drugs for interstitial pulmonary fibrosis (IPF) have been developed. Physicians are becoming increasingly aware of the need for better diagnosis of IPF. To evaluate whether a computer-aided system can improve the diagnostic performance of general radiologists in detecting the usual interstitial pneumonia (UIP) pattern on computed tomography (CT). We included 60 CT datasets from 30 patients with IPF and 30 with idiopathic fibrosing non-specific interstitial pneumonia (fNSIP), all diagnosed by a multidisciplinary diagnosis (MDD) procedure that included surgical biopsy. We analyzed the CT data using a computer-aided system (Gaussian histogram normalized correlation: GHNC). Five general radiologists with <6 years of experience each interpreted these CT scans with and without the GHNC results. We compared the likelihoods of a UIP-pattern diagnosis with the likelihood of the same diagnosis by MDD using the average area under the curve (AUC) of the receiver operating characteristics (ROC). We also evaluated the association between the radiologists' diagnosis and survival using the Kaplan-Meier method. In the ROC analysis, the AUC increased significantly from 0.731 without GHNC to 0.829 with GHNC (P = 0.0396). The diagnosis without GHNC was not significantly associated with survival for any radiologist, but the UIP diagnosis with GHNC was significantly associated with a worse prognosis for four out of five radiologists. The computer-aided system could increase the confidence level of UIP-pattern diagnosis by non-expert radiologists.

Meta-analysis of the radiological and clinical features of Usual Interstitial Pneumonia (UIP) and Nonspecific Interstitial Pneumonia (NSIP).

PurposeTo conduct a meta-analysis to determine specific computed tomography (CT) patterns and clinical features that discriminate between nonspecific interstitial pneumonia (NSIP) and usual interstitial pneumonia (UIP).Materials and methodsThe PubMed/Medline and Embase databases were searched for studies describing the radiological patterns of UIP and NSIP in chest CT images. Only studies involving histologically confirmed diagnoses and a consensus diagnosis by an interstitial lung disease (ILD) board were included in this analysis. The radiological patterns and patient demographics were extracted from suitable articles. We used random-effects meta-analysis by DerSimonian & Laird and calculated pooled odds ratios for binary data and pooled mean differences for continuous data.ResultsOf the 794 search results, 33 articles describing 2,318 patients met the inclusion criteria. Twelve of these studies included both NSIP (338 patients) and UIP (447 patients). NSIP-patients were significantly younger (NSIP: median age 54.8 years, UIP: 59.7 years; mean difference (MD) -4.4; p = 0.001; 95% CI: -6.97 to -1.77), less often male (NSIP: median 52.8%, UIP: 73.6%; pooled odds ratio (OR) 0.32; p<0.001; 95% CI: 0.17 to 0.60), and less often smokers (NSIP: median 55.1%, UIP: 73.9%; OR 0.42; p = 0.005; 95% CI: 0.23 to 0.77) than patients with UIP. The CT findings from patients with NSIP revealed significantly lower levels of the honeycombing pattern (NSIP: median 28.9%, UIP: 73.4%; OR 0.07; p<0.001; 95% CI: 0.02 to 0.30) with less peripheral predominance (NSIP: median 41.8%, UIP: 83.3%; OR 0.21; p<0.001; 95% CI: 0.11 to 0.38) and more subpleural sparing (NSIP: median 40.7%, UIP: 4.3%; OR 16.3; p = 0.005; 95% CI: 2.28 to 117).ConclusionHoneycombing with a peripheral predominance was significantly associated with a diagnosis of UIP. The NSIP pattern showed more subpleural sparing. The UIP pattern was predominantly observed in elderly males with a history of smoking, whereas NSIP occurred in a younger patient population.

Concordance between sequential transbronchial lung cryobiopsy and surgical lung biopsy in patients with diffuse interstitial lung disease

BackgroundIncreasing evidence indicates the utility of transbronchial lung cryobiopsy (TBLC) for the diagnosis of interstitial lung disease (ILD). However, only one study has compared TBLC and surgical lung biopsy (SLB) performed on the same patients.MethodsWe identified seven patients with ILD with TBLC and SLB. We evaluated the clinical characteristics and made a pathological diagnosis based on the official ATS/ERS/JRS/ALAT clinical practice guideline of idiopathic pulmonary fibrosis with both TBLC and SLB.ResultsSix cases were diagnosed as Usual interstitial pneumonia (UIP) in both TBLC and SLB. One case was diagnosed as indeterminate for UIP with TBLC and probable UIP with SLB. Etiological diagnosis with TBLC and SLB were concordant in 2 cases of idiopathic pulmonary fibrosis (IPF) but discordant for other diagnoses. Major histological findings of UIP including dense fibrosis, peripheral distribution, and fibroblastic foci showed high concordance between TBLC and SLB, which implies that TBLC can reliably detect these features. In contrast, loose fibrosis, cellular infiltration, and airway disease showed poor concordance between the two methods.ConclusionOur study showed that TBLC is useful for UIP diagnosis but not for other ILD. With a multidisciplinary approach, diagnosis of IPF may be determined by TBLC, whereas ILD other than IPF may require SLB.

Interpretation of the Chinese Consensus on the Pathological Diagnosis of Usual Interstitial Pneumonia

本刊2018年第3期发表了中国医师协会呼吸医师分会呼吸病理工作委员会组织专家撰写的"普通型间质性肺炎病理诊断中国专家共识（草案）"。本文就该共识撰写的背景、国内普通型间质性肺炎病理诊断的现状以及一些内容的含义进行补充说明及解读，以便病理及临床医生更好地理解及实际应用。.

The role of B cell activating factor in the differential diagnosis of usual interstitial pneumonia

Objective: To explore the differential diagnostic role of B cell-activating factor(BAFF) in idiopathic pulmonary fibrosis (IPF) and usual interstitial pneumonia (UIP) associated with autoimmune diseases (AIDs). Methods: Plasma levels of BAFF were measured by ELISA method in 23 patients with AIDs-UIP, 34 patients with IPF, and 21 healthy subjects as control. The correlation between plasma BAFF levels and other clinical results from patients was analyzed. Receiver operating characteristics (ROC) analysis for distinguishing AIDs-UIP from IPF patients was examined and the maximal area under curve (AUC) was found. Results: Plasma levels of BAFF were significantly elevated in AIDs-UIP patients and IPF patients compared to healthy subjects(P<0.001 and P=0.002, respectively). AIDs-UIP patients had higher level of BAFF than IPF patients(P=0.030). Plasma BAFF levels in AIDs-UIP patients were inversely correlated with pulmonary function results, including FVC%(r=-0.435, P=0.040)and TLC%(r=-0.449, P=0.041), as well as DLCO%(r=-0.491, P=0.024). When the cut off value of BAFF was set as 1.5 ng/ml to distinguish AIDs-UIP patients from IPF patients, the sensitivity and the specificity was 64.5% and 90.0%, respectively, and the area under ROC curve reached the maximum of 0.784(P=0.000, 95% CI: 66.3%-90.5%). Conclusions: Plasma BAFF levels were significantly higher and inversely correlated with pulmonary function, reflecting the severity of AIDs-UIP patients. Plasma BAFF levels may be a useful marker for distinguishing AIDs-UIP from IPF.

Differentiating Usual Interstitial Pneumonia From Nonspecific Interstitial Pneumonia Using High-resolution Computed Tomography: The "Straight-edge Sign".

The purpose of this article was to determine whether a novel finding on coronal computed tomography (CT) can help differentiate usual interstitial pneumonia (UIP) from nonspecific interstitial pneumonia (NSIP) in order to obviate lung biopsy. Two chest radiologists, blinded to clinical data, reviewed 3 preselected coronal images from CT scans, performed within 1 year of surgical lung biopsy (SLB), from 51 patients with biopsy-proven UIP and 15 with biopsy-proven NSIP. The 198 (66×3) images were anonymized and randomized. The radiologists assessed each coronal image for the presence or absence of the straight-edge sign (SES) on both the right and left sides, anecdotally thought to be more common in NSIP than in UIP. The SES was defined as reticulation isolated to the lung bases with sharp demarcation in the craniocaudal plane and without substantial extension along the lateral margins of the lungs. A validation cohort from a second medical center was also evaluated to reassess our findings. The absence of a bilateral SES yielded a sensitivity, specificity, positive predictive value (PPV), and negative predictive value of 56.9%, 93.3%, 96.7%, and 38.9%, respectively, for UIP on SLB. The unilateral or bilateral absence of the SES yielded a sensitivity, specificity, PPV, and negative predictive value of 76.5%, 66.7%, 88.6%, and 45.5%, respectively, for UIP on SLB. For the 11 subjects with an overall CT pattern consistent with NSIP but a pathologic diagnosis of UIP, the SES was absent in 6 (54.5%) subjects. In the validation cohort, the SES was much more common in NSIP than in UIP (46.6% compared with 3.3%, respectively; P<0.001). The absence of the SES has a high PPV for biopsy-proven UIP. Bilateral absence of the SES has high specificity (93.3%) for biopsy-proven UIP. The SES may be useful for differentiating UIP from NSIP.

Can Genomic Analysis Improve the Diagnostic Yield of Transbronchial Biopsy in the Diagnosis of Usual Interstitial Pneumonia?

Can Genomic Analysis Improve the Diagnostic Yield of Transbronchial Biopsy in the Diagnosis of Usual Interstitial Pneumonia?

Smoking-related lung abnormalities on computed tomography images: comparison with pathological findings.

Smoking-related lung abnormalities are now an increasing public health concern. According to the findings of large-cohort studies, approximately 8% of smokers have interstitial lung abnormalities, which are associated with a relatively high risk of all-cause mortality. We reviewed the radiological and pathological findings of smoking-related interstitial lung diseases, such as respiratory bronchiolitis-interstitial lung disease, desquamative interstitial pneumonia, and airspace enlargement with fibrosis. We have also discussed the histological basis of unclassifiable interstitial pneumonia in smokers, which exhibits airway-centered cystic lesions with fibrosis. A variety of radiological findings coexist in the lungs of a smoker. This overlapping of multiple pathological conditions might cause the radiological patterns of diseases to become unclassifiable. Therefore, diagnosis should be performed not on the basis of a single radiological finding, but in a comprehensive manner, by including clinical symptoms and disease behavior. Among interstitial abnormalities in smokers, the usual interstitial pneumonia (UIP) pattern is correlated with a worse prognosis than others. Basal-predominant subpleural reticulation is a clue for accurate diagnosis of UIP, which can be achieved by computer-aided quantitative analysis.