Clinical characteristics of pulmonary Mycobacterium avium complex disease in patients with interstitial lung disease.

OBJECTIVE: Mycobacterium avium complex pulmonary disease (MAC-PD) is occasionally complicated by interstitial lung disease (ILD) in clinical practice, but clinical studies are limited. This study aims to elucidate the clinical and imaging characteristics of MAC-PD in patients with ILD. METHODS: We retrospectively analyzed imaging and clinical data from medical records of 54 consecutive ILD patients diagnosed with MAC-PD from 2011 to 2021 at our institution. We compared the imaging and clinical data of these patients with 2218 ILD patients diagnosed at our institution. RESULTS: The mean age of the patients was 74 years, with 25 males and 29 females, and a mean body mass index (BMI) of 20.0 kg/m2. Compared to all ILD patients, ILD-associated MAC-PD had older ages, lower BMI. The most common underlying ILD diagnosis was unclassifiable interstitial pneumonia. MAC-PD imaging classification was nodular-bronchiectatic (NB) type in 17 patients, fibro-cavitary (FC) type in 15 patients, and unclassifiable (UC) type in 22 patients. Many UC types were difficult to diagnose due to the absence of clear findings indicative of MAC infection. Chronic pulmonary aspergillosis complication was 24.1 %. The mean survival of ILD-associated MAC-PD was 55.6 months, shorter than that of regular MAC-PD. The UC type had a shorter survival than the NB type, similar to the FC type. CONCLUSION: MAC-PD associated with ILD frequently complicates chronic pulmonary aspergillosis and has a poor prognosis. The most common imaging type, UC type, particularly has a shorter survival. Careful management is essential for MAC-PD associated with ILD.

Longitudinal changes in serum immunoglobulin G testing in patients with fibrotic avian hypersensitivity pneumonitis.

BACKGROUND: Evaluation of the antigen responsible for fibrotic hypersensitivity pneumonitis (HP) is challenging. Serum immunoglobulin (Ig) G testing against HP-associated antigens is performed. Although single-serum IgG testing has been investigated, multiple-serum IgG testing has not yet been studied. METHODS: This study included patients who underwent histopathological examination and positive inhalation challenge test as well as those with moderate or high HP guideline confidence level. Serum IgG testing against pigeon serum was conducted twice using two methods: enzyme linked-immunosorbent assay (ELISA) and ImmunoCAP. The association between changes in serum IgG antibody titers and changes in forced vital capacity (FVC) and other parameters was investigated. RESULTS: In this study, 28 patients (mean age, 64.5 years; mean FVC, 85.3%) with fibrotic avian HP were selected, of whom 20 and 8 underwent surgical lung biopsy and transbronchial lung cryobiopsy, respectively. Of the 28 patients, 19 had been keeping birds for more than 6 months. A correlation was observed between the annual changes in serum IgG antibody titers by ELISA and changes in relative FVC (r = - 0.6221, p < 0.001). Furthermore, there was a correlation between the annual changes in serum IgG antibody titers by ImmunoCAP and changes in relative FVC (r = - 0.4302, p = 0.022). Multiple regression analysis revealed that the change in serum IgG antibody titers by both ELISA and ImmunoCAP also influenced the relative FVC change (p = 0.012 and p = 0.015, respectively). Moreover, 13 patients were given additional treatments between the first and second blood test; however, the additional treatment group was not significantly different in relative FVC change compared to the group with no additional treatment (p = 0.982). CONCLUSIONS: In patients with fibrotic avian HP, the annual changes in serum IgG testing were correlated with FVC changes, highlighting the importance of serum IgG testing over time.

Serum Immunoglobulin G Testing against Pigeon Egg in Stable Fibrotic Hypersensitivity Pneumonitis.

INTRODUCTION: The accuracy of serum immunoglobulin (Ig) G testing for diagnosis of stable bird-related fibrotic hypersensitivity pneumonitis (HP) is controversial. Furthermore, avian serum, extracts, or feathers were employed as antigens in bird-related HP; however, the usage of egg whites has not been reported. We investigated the utility of IgG testing against pigeon egg whites in patients with stable bird-related fibrotic HP. METHODS: Patients having a positive inhalation test for pigeon antigen and a histological investigation with diagnostic confidence of fibrotic HP greater than moderate confidence were included. The control group consisted of patients with interstitial lung diseases (ILDs) other than HP. To select patients in the stable phase, patients with fibrotic HP were excluded if they were clinically considered to be in the acute exacerbation or acute phase. The IgG testing against pigeon egg whites by enzyme-linked immunosorbent assay and the commercialized anti-pigeon IgG testing by fluorescence enzyme immunoassay were investigated. RESULTS: In this study, 37 patients with stable bird-related fibrotic HP and 32 patients with ILDs other than HP participated. Serum IgG testing for pigeon egg whites revealed that the control group's optical density was 0.147 and the group with bird-related fibrotic HP had a mean value of 0.207 (p = 0.011). IgG testing in bronchial alveolar lavage fluid was not significantly higher in the bird-related fibrotic HP group than in controls (p = 0.42). No significant difference in area under the curve between an IgG testing against pigeon egg whites and a commercialized anti-pigeon IgG testing was observed (p = 0.24). Test accuracy for stable bird-related fibrotic HP ranged from 62% to 76% sensitivity and 59-66% specificity. CONCLUSION: IgG testing to identify the inciting antigen in patients with stable bird-related fibrotic HP had relatively low accuracy.

Multilineage communication regulates human liver bud development from pluripotency.

Conventional two-dimensional differentiation from pluripotency fails to recapitulate cell interactions occurring during organogenesis. Three-dimensional organoids generate complex organ-like tissues; however, it is unclear how heterotypic interactions affect lineage identity. Here we use single-cell RNA sequencing to reconstruct hepatocyte-like lineage progression from pluripotency in two-dimensional culture. We then derive three-dimensional liver bud organoids by reconstituting hepatic, stromal, and endothelial interactions, and deconstruct heterogeneity during liver bud development. We find that liver bud hepatoblasts diverge from the two-dimensional lineage, and express epithelial migration signatures characteristic of organ budding. We benchmark three-dimensional liver buds against fetal and adult human liver single-cell RNA sequencing data, and find a striking correspondence between the three-dimensional liver bud and fetal liver cells. We use a receptor-ligand pairing analysis and a high-throughput inhibitor assay to interrogate signalling in liver buds, and show that vascular endothelial growth factor (VEGF) crosstalk potentiates endothelial network formation and hepatoblast differentiation. Our molecular dissection reveals interlineage communication regulating organoid development, and illuminates previously inaccessible aspects of human liver development.

Acute Exacerbation and Proposed Criteria for Progressive Pulmonary Fibrosis in Patients with Fibrotic Hypersensitivity Pneumonitis and Idiopathic Pulmonary Fibrosis.

BACKGROUND: Acute exacerbation (AE) occasionally develops in the course of fibrotic hypersensitivity pneumonitis (HP). OBJECTIVE: The aim of the study was to compare AE of fibrotic HP with that of idiopathic pulmonary fibrosis (IPF). METHODS: Consecutive patients with pathologically confirmed fibrotic HP and IPF diagnosed based on a multidisciplinary discussion were included in the analysis. AE in patients with fibrotic HP and IPF was evaluated retrospectively. RESULTS: This study included 309 and 160 patients with fibrotic HP and IPF, respectively. Their 50% survival times were 96.1 and 78.0 months, respectively (hazard ratio [HR]: 0.54 [95% confidence interval, CI: 0.36-0.77], log-rank test; p < 0.001). Notably, the cumulative AE rates of fibrotic HP were 3% at 1 year and 10% at 3 years. Moreover, the corresponding rates of IPF were 8% at 1 year and 20% at 3 years (HR: 0.66 [95% CI: 0.45-0.93], log-rank test; p = 0.034). The 90-day survival rates from the AE onset of fibrotic HP and IPF were 75% and 64%, respectively (HR: 0.51 [95% CI: 0.31-0.83], log-rank test; p = 0.006). The respiratory function test on the physiological criteria of progressive pulmonary fibrosis (PPF) was a predictor of AE in fibrotic HP. However, the high-resolution CT (HRCT) changes in the criteria of PPF were not. Nevertheless, both the physiological and radiological criteria of PPF were a predictor of AE of IPF. CONCLUSION: AE of fibrotic HP has a lesser prognostic effect than that of IPF. HRCT criteria for PPF were not a risk factor for AE in patients with fibrotic HP.

Validation of inhalation challenge test and serum immunoglobulin G test for bird-related fibrotic hypersensitivity pneumonitis.

BACKGROUND: The inhalation challenge test is considered to be the item for diagnosis of hypersensitivity pneumonitis (HP) and identifying the causative antigen in patients with fibrotic HP. However, the inhalation challenge test is not widely used. OBJECTIVE: To evaluate the values of the inhalation challenge test by comparing with serum immunoglobulin (Ig)G test. METHODS: This was a single-center, retrospective study. The patients with fibrotic HP were diagnosed pathologically by surgical lung biopsy or transbronchial lung cryobiopsy and were assumed to have bird-related fibrotic HP if they had a history of obvious avian exposure. RESULTS: On the basis of pathologic findings and history of avian exposure, 43 of 86 patients were diagnosed with having bird-related fibrotic HP. In 43 patients with bird-related fibrotic HP, 15 (35%) were positive for anti-bird IgG antibody and 36 (84%) were positive for the inhalation challenge test; in addition, the specificity of the inhalation challenge test was 67%. Patients with both positive results from inhalation challenge test and anti-bird IgG antibodies had a 2.7% decline in annual forced vital capacity (FVC) before the inhalation (P = .02). In patients with positive result from inhalation challenge test and negative result from anti-bird IgG antibodies, the annual FVC decreased by 5.8% (P = .03). FVC was not consistent in patients with positive result from the anti-bird IgG antibodies. CONCLUSION: The inhalation challenge test for bird-related fibrotic HP was more sensitive than the anti-bird IgG antibodies. Furthermore, the inhalation challenge test could select patients with similar disease progression.

Establishment of PDX-derived salivary adenoid cystic carcinoma cell lines using organoid culture method.

To generate a reliable preclinical model system exhibiting the molecular features of salivary adenoid cystic carcinoma (ACC) whose biology is still unclear due to the paucity of stable cell cultures. To develop new in vitro and in vivo models of ACC, the techniques of organoid culture and patient-derived tumor xenograft (PDX), which have attracted attention in other malignancies in recent years, were applied. Tumor specimens from surgically resected salivary ACC were proceeded for the preparation of PDX and organoid culture. The orthotopic transplantation of patient-derived or PDX-derived organoids was demonstrated into submandibular glands of NSG mice and those histology was evaluated. PDX-derived organoid cells were evaluated for the presence of MYB-mediated fusion genes and proceeded for in vitro drug sensitivity assay. Human ACC-derived organoids were successfully generated in three-dimensional culture and confirmed the ability of these cells to form tumors by orthotopic injection. Short-term organoid cell cultures from two individual ACC PDX tumors were also established that maintain the characteristic MYBL1 translocation and histological features of the original parent and PDX tumors. Finally, the establishment of drug sensitivity tests on these short-term cultured cells was confirmed using three different agents. This is the first to report an approach for the generation of human ACC-derived organoids as in vitro and in vivo cancer models, providing insights into understanding of the ACC biology and creating personalized therapy design for patients with ACC.

Clinical characteristics of Japanese patients with moderate to severe COVID-19.

INTRODUCTION: Although several reports on the risk factors for severe disease of COVID-19 already exist, reports on effective early indicators are still limited, especially from Japan. This study was conducted to clarify the patient's characteristics whose disease progressed to severe status. METHODS: The medical records of all consecutive 300 Japanese patients hospitalized at our institution between February and November 2020 were retrospectively reviewed. The clinical characteristics were evaluated to compare between mild (no oxygen needed), moderate (oxygen needs of 1-4 L/min), and severe diseases (oxygen needs of 5 L/min or more). RESULTS: The median age was 68 years old, with 123 (41.0%) males and 177 (59.0%) females. Of these, 199 patients (66.3%), 55 patients (18.3%), 46 patients (15.3%) patients were in the mild disease, moderate disease, severe disease groups, respectively. Patients with severe disease were more likely to be older, have more comorbidities, and tended to have higher body mass index. In laboratory data, lymphocyte count, levels of C-reactive protein (CRP), LDH, and AST on admission were significantly associated with the severity. In multivariate analysis, age and CRP were the independent risk factors for severe disease (OR = 1.050, 1.130, respectively). The optimal cut-off value for age was 74 years old and that for CRP was 3.15 mg/dL. CONCLUSIONS: Age and CRP were independently associated with disease severity of COVID-19 in multivariate analysis. Additionally, the numbers of underlying disease, lymphocyte count, and inflammatory markers such as LDH and D-dimer may also be related to disease severity.

Inhalation challenge test using pigeon eggs for chronic hypersensitivity pneumonitis.

BACKGROUND: Chronic hypersensitivity pneumonitis (CHP) remains a diagnostic challenge. The process of collecting and extracting serum and droppings from causative animals for the inhalation challenge test is complicated and the risk of inducing disease progression exists. OBJECTIVE: To investigate the utility and safety of an inhalation challenge test using pigeon eggs. METHODS: Pigeon eggs were pasteurized and mixed with a saline solution to produce an inhalation fluid. An inhalation challenge test was conducted on 19 patients with bird-related CHP and 17 patients with interstitial lung disease other than bird-related CHP. To identify antigens in pigeon eggs, the antigen-antibody responses of the pigeon eggs and serum from patients were evaluated using Western blotting. RESULTS: The mean changes in C-reactive protein, alveolar-arterial oxygen difference, erythrocyte sedimentation rate, and lactate dehydrogenase significantly increased by 0.32 mg/dL (P = .014), 7.8 Torr (P = .002), 1.4 mm/h (P = .012), and 5.4 U/mL (P = .0019), respectively, in bird-related CHP group compared to the control 24 hours after the inhalation challenge test. Furthermore, within 24 hours of the inhalation test, the mean forced vital capacity decreased by 2.3% in the bird-related CHP group compared with a decline of 0.05% in the control group (P = .035). Serum collected from seven bird-related CHP patients who underwent the inhalation challenge test and reacted to antigens with molecular weights of 37-75 KDa, and these molecular weights were consistent with egg albumin and globulin. CONCLUSION: Since a mild response was observed after the inhalation challenge test using pigeon eggs, this test was an obvious candidate for diagnosing bird-related CHP.

Evaluation of lymphocytic infiltration in the bronchial glands of Sjögren's syndrome in transbronchial lung cryobiopsy.

BACKGROUND: Sjögren's syndrome (SS) is a systemic autoimmune disease characterized by deteriorated exocrine gland function with associated lymphocytic infiltration. However, there are few pathological studies on bronchial glands in SS. In this study, we aimed to clarify pathological features of bronchial glands in SS. METHODS: We retrospectively evaluated infiltration of lymphocytes in the bronchial glands incidentally collected by transbronchial lung cryobiopsy (TBLC), which were performed for the diagnosis of diffuse lung diseases. The degrees of lymphocyte infiltration in the bronchial glands were classified into four grades (grade 0-3). We compared the degrees of infiltration of SS with those of other diffuse lung diseases. RESULTS: TBLC for diagnosis of diffuse lung diseases were performed on 432 cases during the study period. The samples of 50 cases included bronchial glands. Of those, 20 cases were excluded due to insufficient size or influence of therapy. The remaining 30 cases included 17 of idiopathic interstitial pneumonias, 5 of chronic hypersensitivity pneumonia, 6 of connective tissue disease (SS; n = 4, systemic sclerosis; n = 1, dermatomyositis; n = 1) and 2 of other diseases. In SS, infiltration of lymphocytes was observed in all cases; grade 1 in one, grade 2 in one, and grade 3 in two cases. In contrast, 11 of 26 in other diseases showed no lymphocytes infiltration, with the remaining 15 of grade 1 infiltration. Grade 2 or more infiltration were found only in SS but not in other diseases. CONCLUSION: Our results suggested that high-grade lymphocytic infiltration of bronchial glands is a distinct characteristics in SS.

Nationwide cloud-based integrated database of idiopathic interstitial pneumonias for multidisciplinary discussion.

Multidisciplinary discussion (MDD) requiring close communication between specialists (clinicians, radiologists and pathologists) is the gold standard for the diagnosis of idiopathic interstitial pneumonias (IIPs). However, MDD by specialists is not always feasible because they are often separated by time and location. An online database would facilitate data sharing and MDD. Our aims were to develop a nationwide cloud-based integrated database containing clinical, radiological and pathological data of patients with IIPs along with a web-based MDD system, and to validate the diagnostic utility of web-based MDD in IIPs.Clinical data, high-resolution computed tomography images and lung biopsy slides from patients with IIPs were digitised and uploaded to separate servers to develop a cloud-based integrated database. Web-based MDD was performed using the database and video-conferencing to reach a diagnosis.Clinical, radiological and pathological data of 524 patients in 39 institutions were collected, uploaded and incorporated into the cloud-based integrated database. Subsequently, web-based MDDs with a pulmonologist, radiologist and pathologist using the database and video-conferencing were successfully performed for the 465 cases with adequate data. Overall, the web-based MDD changed the institutional diagnosis in 219 cases (47%). Notably, the MDD diagnosis yielded better prognostic separation among the IIPs than did the institutional diagnosis.This is the first study of developing a nationwide cloud-based integrated database containing clinical, radiological and pathological data for web-based MDD in patients with IIPs. The database and the web-based MDD system that we built made MDD more feasible in practice, potentially increasing accurate diagnosis of IIPs.

Safety of pyrazinamide-including regimen in late elderly patients with pulmonary tuberculosis: A prospective randomized open-label study.

Pyrazinamide (PZA) -including regimen had not been fully recommended for late elderly patients with tuberculosis (TB) by Japanese Society for Tuberculosis until 2018. Studies on the safety of adding PZA to other first-line TB drugs for late elderly patients are limited. In this prospective randomized open-label study, we aimed to assess the safety of regimen including PZA for patients aged 80 or older. Patients in their eighties with smear-positive pulmonary TB without any liver diseases were randomly assigned to HRE (isoniazid, rifampicin, ethambutol) group or HREZ (HRE and PZA) group. The primary endpoint was discontinuation or interruption rate of treatment due to liver injury. Other endpoint included overall rate of liver injury, time to culture conversion, and overall mortality. Eighty-nine patients were assigned to either HRE group (n = 45) or HREZ group (n = 44). Clinical background was not different in two groups including age, smear grade, body weight, serum albumin, and activity degree. Discontinuation of treatment due to liver injury occurred in 15.6% of HRE group and 9.1% of HREZ group, which showed no statistical difference. Incidence of liver injury was also comparable between two groups. Overall mortality was statistically higher in HREZ group (3 in HRE vs. 10 in HREZ), although all deaths seemed to be irrelevant to PZA use. Time to culture conversion was significantly shorter in HREZ group (43.6 days vs. 30.2 days). In conclusion, regimen including PZA seems to be safe for late elderly patients with pulmonary TB.

Negative impact of anorexia and weight loss during prior pirfenidone administration on subsequent nintedanib treatment in patients with idiopathic pulmonary fibrosis.

BACKGROUND: Current clinical practice guidelines for idiopathic pulmonary fibrosis (IPF) conditionally recommend use of pirfenidone and nintedanib. However, an optimal treatment sequence has not been established, and the data of treatment sequence from pirfenidone to nintedanib are limited. This study aimed to evaluate safety, tolerability and efficacy of nintedanib switched from pirfenidone in patients with IPF. METHODS: Thirty consecutive IPF cases, which discontinued pirfenidone because of a decline in forced vital capacity (FVC) or intolerable adverse event (AE), and newly started nintedanib (150 mg twice daily) from September 2015 to August 2017 (switch-group) were retrospectively reviewed. Subsequently, we compared the characteristics, treatment status, and AEs between the switch-group and other 64 IPF patients newly started nintedanib during the same period without any prior anti-fibrotic treatment (pirfenidone-naïve group). RESULTS: In the switch group, median age, body weight, body mass index (BMI), and %FVC were 72 years old, 54.9 kg, 21.0 kg/m2, and 52.9%, respectively. Most common AE of nintedanib was aspartate aminotransferase/alanine aminotransferase elevation (71.9%), followed by anorexia (46.7%) and diarrhea (46.7%); whereas, anorexia (63.3%) and ≥ 5% weight loss from baseline (56.7%) were common during pirfenidone administration. Sixteen patients (53.3%) discontinued nintedanib within 6 months (early termination). Multivariate logistic regression analysis revealed a significant association between low BMI and early nintedanib termination in the switch-group (p = 0.0239). Nintedanib suppressed FVC decline as compared with that during administration period of pirfenidone in 70% of the patients who could undergo lung function before and after switching to nintedanib. The incidence of early termination of nintedanib was higher in the switch-group than in the pirfenidone-naïve group, whereas body-weight, BMI, absolute FVC values, and %FVC were significantly lower in the switch-group (just before nintedanib initiation) than in the pirfenidone-naïve group. Nintedanib-induced anorexia was more frequent and severer in the switch-group than in the pirfenidone-naïve group, but no significant differences were observed in terms of other AEs. CONCLUSIONS: A high incidence of early termination of nintedanib was noted when patients were switched from pirfenidone. Anorexia and weight loss during prior pirfenidone administration may increase the rate of the early termination of subsequent nintedanib treatment.

Predictive Factors for the Long-Term Deterioration of Pulmonary Function in Interstitial Lung Disease Associated with Anti-Aminoacyl-tRNA Synthetase Antibodies.

BACKGROUND: Little has been reported on long-term pulmonary function trends among patients with interstitial lung disease associated with anti-aminoacyl-tRNA synthetase antibodies (ARS-ILD). OBJECTIVES: To clarify the factors predictive of progression in ARS-ILD based on patients' initial clinical and radiological features. METHODS: The clinical courses of 88 patients with > 1 year of follow-up data on pulmonary function tests (PFTs) were retrospectively analyzed. Disease behavior was categorized into three groups: (1) improved or (2) worsened (defined as increases or decreases, respectively, of > 10% in forced vital capacity and > 15% in %diffusing capacity of lung carbon monoxide) or (3) stable based on PFT changes compared between 1-year results as the initial data and results at 3 years to assess the long-term course. RESULTS: In the initial course of 75 patients with ARS-ILD who received anti-inflammatory therapy within 6 months after diagnosis, 48 patients (64.0%) improved and 6 patients (8.0%) worsened. The radiological patterns in the patients with ARS-ILD included nonspecific interstitial pneumonia (NSIP) in 46.7% and NSIP with organizing pneumonia overlap in 52.0% of the cases. One-third of the initially improved patients who worsened over the long-term course were assigned to the unstable group. By multivariate logistic analysis, middle lobe traction bronchiectasis was a significant predictive factor for the patients in the unstable group. CONCLUSIONS: Most patients with ARS-ILD receiving anti-inflammatory therapy had improved or remained stable in the first year. However, over the long-term course, some patients worsened despite their initial improvement. Even though the extent of the disease is limited, middle lobe traction bronchiectasis in ARS-ILD may be a useful predictor of poor long-term disease behavior.

Unilateral Upper Lung Field Pulmonary Fibrosis Radiologically Consistent with Pleuroparenchymal Fibroelastosis after Thoracotomy: A New Disease Entity Related to Thoracotomy.

BACKGROUND: Pleuroparenchymal fibroelastosis (PPFE) is a rare bilateral idiopathic interstitial pneumonia defined by pleural-parenchymal involvement. In clinical practice, we encountered patients with upper lung field pulmonary fibrosis (Upper-PF), which was radiologically consistent with PPFE, but apparently limited to the unilateral lung. OBJECTIVES: The purpose of the study was to clarify the clinical characteristics in those patients. METHODS: We examined the medical records of all the consecutive patients from 2012 to 2016 to see whether there were patients having unilateral Upper-PF. RESULTS: We found 6 patients with unilateral Upper-PF. The most common symptom was dyspnea, and all patients had a low body mass index and severe restrictive pulmonary impairment. Notably, all patients had a history of thoracotomy for resecting lung or esophageal cancer, and the lesions were limited to the operated side. Dynamic breathing chest MRI showed an impaired thoracic movement in the operated side. Serial chest CT from prethoracotomy to the first visit was obtained in 5 patients: before thoracotomy, only a slight apical cap, defined as a wedge- and triangle-shaped opacity with broad pleural contact, was observed only in the operated side, but progressed into the lesion after a median of 8.4 years following thoracotomy. After the first visit, the unilateral lesion rapidly deteriorated in all patients. CONCLUSIONS: Unilateral Upper-PF had some characteristics in common with PPFE. Because the lesion was limited to the operated side, unilateral Upper-PF would be a new disease entity related to thoracotomy. Our results indicate that thoracotomy impairs thoracic movement in the operated side and subsequently triggers unilateral Upper-PF development, especially in patients with an apical cap.

Compatible with fibrotic hypersensitivity pneumonitis on high-resolution computed tomography: from the ATS/JRS/ALAT 2020 hypersensitivity pneumonitis guidelines.

Background: In compatible with fibrotic hypersensitivity pneumonitis (HP) of the computed tomography (CT) classification using the American Thoracic Society (ATS)/Japanese Respiratory Society (JRS)/Latin American Thoracic Association (ALAT) HP guidelines, the lung fibrosis pattern was classified as either a usual interstitial pneumonia (UIP) pattern or a diffuse ground-glass opacity (GGO) pattern with subtle fibrosis. We investigated whether patients with the same imaging classification had different disease progression. We also attempted to reclassify these patients using the CHEST HP guidelines. Methods: Patients with fibrotic HP who had compatible CT pattern in the ATS/JRS/ALAT classification were investigated retrospectively. Results: With 62 patients in the UIP pattern group and 25 patients in the diffuse GGO pattern group, 87 patients with fibrotic HP had compatible pattern on CT. Annual forced vital capacity changes in the UIP pattern group and diffuse GGO pattern group were -2.7% and +3.3% (P=0.004), respectively. The 5-year survival rates in the UIP pattern group and diffuse GGO pattern group were 86% and 100% (P=0.02). In UIP pattern group in the ATS/JRS/ALAT classification, 27% patients were classified as typical fibrotic HP pattern in the CHEST guidelines. In the diffuse GGO pattern group, 52% patients were classified as typical pattern of fibrotic HP. In the CHEST guidelines, more patients in the GGO pattern were classified as typical pattern compared with those in the UIP pattern (P=0.02). Conclusions: The two patterns in compatible with fibrotic HP of CT classification using the ATS/JRS/ALAT HP guidelines had different disease progression. Typical patterns were more frequent in the CHEST guidelines than the ATS/JRS/ALAT guidelines.

Nonfibrotic (cellular) hypersensitivity pneumonitis with and without slight lung distortion.

BACKGROUND: According to international diagnostic guidelines for hypersensitivity pneumonitis (HP), cases with both nonfibrotic and fibrotic lesions are classified by the predominant feature. Therefore, some cases with nonfibrotic HP, have inflammatory lesions alone, while others have a mixture of fibrosis and inflammation. We investigated the impact of slight fibrotic lesions in nonfibrotic HP. METHODS: This retrospective study included nonfibrotic HP cases with <10% of lung distortion on high-resolution CT. We divided the cases into two groups: those with pure ground glass opacities (GGOs) without lung distortion and those with slight lung distortion of <10%. RESULTS: In this study, 37 cases were included. The mean baseline forced vital capacity (FVC) was 109% in the pure GGO group and 96% in the slight lung distortion group (p = 0.038). After 1 year, the reticular shadows appeared or increased more in the slight lung distortion group than in the pure GGO group (16% vs. 8%, p = 0.030). The time to medication initiation was significantly shorter in the slight lung distortion group than in the pure GGO group (p = 0.044). %FVC decreased by ≥ 5% from diagnosis in no cases with the pure GGO and in two cases with the slight lung distortion (-11.0% for 9.5 years and -10.7% for 1.3 years, respectively). CONCLUSIONS: The slight distortion group exhibited a higher rate of worsening and new appearance of reticular shadows after 1 year and a shorter time to first medication compared to the pure GGO group.

Hypersensitivity pneumonitis with Paecilomyces as suspected inciting antigen.

A 73-year-old man visited our hospital for persistent cough. Chest high-resolution CT (HRCT) showed infiltration shadows in lower lobes and diffuse ground glass opacities in the upper lobes. Blood tests showed elevated white blood cell, C-reactive protein, surfactant protein D, and Krebs von den Lungen-6 levels. After an antigen avoidance test, his HRCT and blood test findings improved; we diagnosed him with hypersensitivity pneumonitis (HP). A culture of the rotting interior walls within his home revealed Paecilomyces, which we believe caused his HP. Given the few patients with Paecilomyces-induced HP, systematic approach was important to identify the inciting antigen.

Multidisciplinary Discussion for Fibrotic Hypersensitivity Pneumonitis with a Positive Antigen Avoidance.

Background: In the two fibrotic hypersensitivity pneumonitis (fHP) diagnostic guidelines, the multidisciplinary discussion (MDD) is required to be performed in diagnosis of fHP, as in idiopathic pulmonary fibrosis (IPF) diagnostic guideline. Although some patients with fHP can improve disease condition during antigen avoidance, which can facilitate the diagnosis of fHP, it is unclear if MDD is necessary in all patients with suspected fHP who improved an antigen avoidance. Objective: To investigate the diagnosis of fHP via MDD with positive antigen avoidance tests (AATs) and the clinical diagnosis with positive AATs. Methods: A single-center, retrospective study was conducted. Between 2012 and 2019, patients with fHP were enrolled in the study. Patients in the MDD diagnostic group consisted of patients diagnosed with MDD, including histopathology findings and positive ATTs, and patients in the clinical diagnostic group were diagnosed by two respiratory physicians and had positive ATTs. Results: AAT was performed on 72 of 219 patients, and 58 had positive AATs. The study included 37 patients in the MDD diagnosis group and 21 patients in the clinical diagnosis group. No significant differences in overall survival (OS) were detected between the two groups (HR: 1.99 [95% CI: 0.82‒4.83], p = 0.127). The conducting MDD was not a risk factor for OS; only <79% forced vital capacity was a risk factor in the multivariate Cox hazard regression analysis. No significant difference in annual changes of forced vital capacity, diffusion of the lung for carbon monoxide and Krebs von den Lungen-6 between the MDD diagnostic and the clinical diagnostic groups were observed (p = 0.41, 0.79, and 0.81, respectively). Conclusion: In patients with positive AATs, the disease progression of the MDD diagnostic and the clinical diagnostic groups were similar. Therefore, MDD could not be necessary in all patients with suspected fHP who had positive AATs.

A Retrospective Study of the Clinical, Radiological, and Pathological Characteristics of Patients with Interstitial Pneumonia Preceding Rheumatoid Arthritis.

Objective Interstitial lung disease (ILD) is the most critical manifestation in patients with rheumatoid arthritis (RA). In some cases, ILD may appear before the RA onset. Some patients with an initial diagnosis of idiopathic interstitial pneumonia (IIPs) develop RA; however, few studies have reported on its features, and the details remain unknown. In the present study, the clinical, radiological, and pathological features were evaluated in patients with ILD preceding RA. Methods The clinical, radiological, and pathological features of patients with ILD preceding RA were retrospectively reviewed using the medical records. Patients Ten patients with ILD preceding RA out of 883 IIP patients who underwent a surgical lung biopsy at our hospital from 2004 to 2018 were retrospectively examined. Results The median patient age was 59 (range 50-76) years old, and 7 of the patients were women. The median time from the ILD diagnosis to the RA onset was 50 (range 33-65) months. Regarding the high-resolution computed tomography pattern, the "indeterminate for UIP" pattern was the most popular, and cysts were seen in all cases. Attenuation around the cyst was prominent. Pathological findings showed plasma cell infiltration, bronchus-associated lymphoid tissue (BALT), and bronchiolitis in the lobules. Cellular and destructive bronchiolitis was noticeable in many patients with ILD preceding RA and contributed to the destruction and dilation of the bronchiole. Conclusion In ILD patients with IIP, radiological and pathological findings with increased attenuation around the cysts, prominent inflammatory cell infiltration (especially in plasma cells), an increase in the BALT number, and cellular and destructive bronchiolitis might serve as helpful RA development indicators.