Paraseptal Emphysema in Indium Lung: Tracing the Pathological Footprints of Chronic Exposure.

Indium lung is an occupational lung disease caused by exposure to indium-tin-oxide (ITO) dust. Compared to other occupational lung diseases, indium lung has a shorter latency period and the respiratory status continues to worsen even after exposure to the work environment improves. Paraseptal emphysema which affects mainly the subpleural area is seen on chest images obtained via computed tomography (CT), regardless of the smoking history. However, the pathogenesis of emphysema in indium lung is still unclear. Therefore, we re-evaluated the pathology of three previously reported cases of indium lung. Paraseptal emphysema was observed in both smokers and nonsmokers. Obstructive respiratory impairment worsened over time in the cases with paraseptal emphysema. Many alveolar walls were destroyed independent of the presence or absence of emphysetamous changes or fibrosis. Moreover, bronchiolitis was found to be less common in indium lung than in asbestosis (the most common occupational lung disease) or common cases of chronic obstructive pulmonary disease caused by smoking. It has been shown that ITO causes protease anti-protease imbalance, oxidant-antioxidant imbalance, and continuous, abnormal inflammation (the three major causes of emphysema). In addition, nano-sized ITO is less likely to be trapped in the upper airways and may easily reach the subpleural alveoli. Furthermore, ITO may continue to cause sustained tissue injury at the alveolar level potentially resulting in emphysema. Further studies are needed to elucidate the detailed pathogenesis of indium lung by comparing it with other occupational lung diseases.

Polyclonal Hyperglobulinemia with Multiple Pulmonary Cysts and Nodules: Concerning the Mechanism Underlying Cyst Formation.

We herein report a case of polyclonal hyperglobulinemia with multiple pulmonary cysts and nodules. The histopathological findings allowed us to speculate about the mechanism underlying cyst formation in these pathological conditions, which has not yet been thoroughly elucidated. The patient was a 49-year-old woman who presented with multiple pulmonary multilocular cysts and nodules. A lung biopsy revealed features of nodular lymphoid hyperplasia. Notably, lung structure fragmentation was evident, suggesting that structural destruction may have accompanied the disease during its course. The cysts were considered to have formed due to destruction of the lung structures.

Drug-induced lung disease due to topical minoxidil.

A 55-year-old man presented to our institution with abnormal chest X-ray shadows. Chest computed tomography (CT) showed left-sided interlobular septal thickening; thus, we suspected lymphangitis carcinomatosis and other disorders that show similar CT findings. Bronchoscopy and laboratory and imaging studies yielded no diagnostic findings. Pulmonary shadows during follow-up spontaneously improved then worsened. Thoracoscopic lung biopsy samples showed interstitial pneumonia and granulomas but the etiology of the pulmonary lesion could not be determined. At seven years after presentation, the patient's pulmonary shadows had gradually deteriorated, and he reported using topical minoxidil. His history of minoxidil use was linked to changes in the pulmonary shadows. The diagnostic delay was due to the patient's hesitancy to report drugs obtained online and the difficulty in obtaining such a history.

Diffuse cryptococcal pneumonia in multicentric Castleman's disease with elevated serum IgG4.

A woman in her 60s with suspected multicentric Castleman's disease, who was receiving treatment with oral prednisolone, presented to our hospital with mild cough and malaise. Chest CT showed diffuse infiltrative and granular shadows, indicating exacerbation of lung lesions caused by steroid-resistant multicentric Castleman's disease. A video-assisted thoracoscopic lung and mediastinal lymph node biopsy was performed. The biopsy revealed mediastinal lymph node tissue consistent with multicentric Castleman's disease, as well as presence of Cryptococcus neoformans in the alveolar space. C. neoformans infection in immunocompromised individuals may present with diffuse lung lesions and should be noted as a mimicker of acute exacerbation of Castleman's disease.

Progression of Smoking-Induced Emphysema in a Case with Indium Lung.

Recently, it has become clear that inhaled indium-tin oxide causes emphysematous as well as interstitial changes in the lung. Here, we present a 59-year-old male ex-smoker, quitting smoking at the age of 55. He had been engaged in indium-tin oxide processing from 27 to 37 years of age, with 22 years having passed since the final exposure to indium. He was found to have a high serum indium concentration and Krebs von den Lungen-6 (KL-6). Furthermore, bilateral centrilobular emphysema was recognized in high-resolution computed tomography (HRCT). After transferring jobs to a non-indium-tin oxide section, KL-6 returned to a normal level within 4 years, whereas neither serum indium concentration nor emphysema had decreased to normal despite 22 years having passed since the exposure ended. At the age of 59, a thoracoscopic lung biopsy was performed to assess the contribution of smoking and that of indium to the lung destruction. The pathological findings demonstrated cholesterol granulomas with the accumulation of macrophages and multinucleated giant cells that had phagocytosed particles. Together with the typical findings of indium lung, fibrotic and emphysematous changes were observed. The elemental analysis of the biopsied specimens revealed excessive deposition of indium throughout the airways, interstitial spaces and alveoli. The pathological findings of this case may be the result of two kinds of pulmonary damage, i.e., smoking and indium. This report indicates that occupationally-inhaled indium could remain in the lung for as long as 22 years and continue to insult the lung tissue with inflammation caused by smoking.

Bilateral lung transplantation in a 9-year-old girl with bronchopulmonary dysplasia with pulmonary hypertension.

BACKGROUND: Bronchopulmonary dysplasia (BPD) is a chronic respiratory disease that occurs in premature infants and the prognosis is variable depending on the comorbidities including fibrosis, emphysema, or pulmonary hypertension (PH). We present a case of a 9-year-old girl who developed PH associated with severe BPD (BPD-PH) and underwent bilateral lung transplantation (BLTx). Case description A 9-year-old girl was admitted to our department to undergo BLTx. She was born at 23 weeks and 4 days gestation with a weight of 507 g. She received ventilation for the first 2 months and required further respiratory care due to repetitive, severe respiratory infections. She was diagnosed with BPD-PH at 6 months of age and oral administration of pulmonary vasodilators were initiated. She was registered as a lung transplant candidate at 4 years of age after the life-threatening exacerbation. Chest computed tomography (CT) revealed severe lung conditions with ground-glass opacities and emphysematous low-density areas in the upper and lower lobes. BLTx from a brain-dead male donor was performed. The pathological findings of her resected lung revealed saccular, hypoplastic lung with alveolar repair/regeneration, and medial hypertrophy and muscularization of peripheral arteries. The postoperative course was mostly uneventful. She was free from oxygen administration and showed no signs of PH after 6 months of the surgery. CONCLUSION: This is the first case report of BLTx in a pediatric, irreversible BPD-PH patient with detailed pathohistological findings and clinical examination. Lung transplantation is one of the treatment options for severe BPD-PH.

Slowly progressive interstitial lung disease preceding typical dermatomyositis symptoms in anti-melanoma differentiation-associated gene 5 antibody-positive clinically amyopathic dermatomyositis.

A 73-year-old woman who visited our hospital complaining of dry cough for three months was refractory to antimicrobial therapy. Chest computed tomography revealed subpleural consolidation. Specimens obtained from surgical lung biopsy revealed subpleural perilobular airspace organization and fibrosis. After the biopsy, mechanic's hand and Gottron's papules appeared, and anti-melanoma differentiation-associated gene 5 (MDA5) antibody was found to be positive. Subsequently, anti-MDA5 antibody measured in cryopreserved serum from her first admission proved to be positive. It is difficult to suspect the presence of anti-MDA-5 antibody in patients with interstitial lung disease without typical dermatomyositis symptoms or slow disease progression.

Rheumatoid Arthritis Accompanying Diffuse Panbronchiolitis.

A 58-year-old woman with rheumatoid arthritis (RA) visited our hospital complaining of a persistent cough and sputum for the past year. She had a high cold hemagglutinin titer and chronic sinusitis. Chest computed tomography revealed bilateral diffuse centrilobular nodules, bronchiectasis, and bronchial wall thickening. A surgical lung biopsy was performed that confirmed diffuse panbronchiolitis (DPB) because of the lymphocytic and plasmacytic infiltrates in the respiratory bronchioles. Her condition improved after the administration of clarithromycin. Several cases of RA complicating DPB have previously been reported, but only in Japan. We need to consider DPB as a bronchiolitis types accompanying RA among Japanese patients.

Diffuse Pulmonary Ossification with Connective Tissue Weakness Potentially Due to Vascular Ehlers-Danlos Syndrome.

A 30-year-old non-smoking man was referred to our hospital for the further examination of abnormal shadows revealed by chest X-ray. He had mild shortness of breath. Chest computed tomography revealed a fine-grained dendritic shadow with diffuse calcification in both lungs and as well as emphysematous changes in the upper lung lobes. A surgical lung biopsy histology revealed diffuse pulmonary ossification complicated with lung laceration, vascular disruption, hemosiderosis, and emphysema, suggesting vascular Ehlers-Danlos syndrome (vEDS). However, the patient had no external physical signs or family history of vEDS and no COL3A1 gene mutations. We are closely monitoring this patient in the clinic.

Asymmetrical Interstitial Lung Disease Suggested to Be Due to Hypoplasia of the Unilateral Pulmonary Artery: A Case Report with a 20-year Follow-up.

We herein report a case of asymmetrical interstitial lung disease (ILD) that remained almost completely asymmetrical over time on chest computed tomography (CT). An open lung biopsy from the right lung showed severe pleural adhesion, obstruction of the pulmonary artery, and dilated systemic arteries in addition to the usual interstitial pneumonia pattern. Three-dimensional CT angiography showed partial defects of pulmonary arteries on the affected side. After excluding other known causes of ILD and gastroesophageal reflux, we suspected that decreased pulmonary artery perfusion in the present case may have been responsible for the observed asymmetrical unilateral fibrosis.

An unusual case of eosinophilic lung disease with multiple cyst formation.

We report here an unusual case of eosinophilic necrotizing inflammation of the lung that mimicked chronic eosinophilic pneumonia. A 71-year-old man who lived in an unsanitary environment and was referred to our hospital with suspected pneumonia. Peripheral blood eosinophilia was observed, and computed tomography indicated extensive consolidation with multiple cystic lesions, mainly in the left lung. A histological analysis using video-assisted thoracic surgery revealed diffuse infiltration of inflammatory cells into the alveolar wall and massive accumulation of macrophages and eosinophils in the airspace. Many tiny eosinophilic abscesses were scattered through the tissue. These findings were more severe than those associated with chronic eosinophilic pneumonia. Immunostaining revealed the deposition of eosinophil granular protein and the presence of extracellular traps and Charcot-Leyden crystals, which suggested excessive eosinophil activation. Interestingly, the patient's symptoms and clinical findings gradually improved without treatment after admission. He was discharged to a clean residence and did not have a recurrence for 19 months. The observations suggest a hypersensitivity reaction to an environmental allergen and consequent multiple cyst formation in association with eosinophilic necrotizing inflammation, although further studies are warranted.

Dasatinib-induced Nonspecific Interstitial Pneumonia That Developed 7 Years after the Initiation of Dasatinib.

We report the case of a 56-year-old man with chronic myeloid leukemia (CML) who developed dasatinib-induced interstitial lung disease (ILD) 7 years after starting dasatinib, a BCR-ABL1 inhibitor. The patient presented with dyspnea. Chest imaging showed diffuse ground-glass opacities. A surgical lung biopsy showed cellular non-specific interstitial pneumonia (NSIP). Corticosteroid treatment ameliorated his condition. Bosutinib, another BCR-ABL1 inhibitor, was successfully re-instituted. The present case and relevant literature suggest that dasatinib-induced ILD can present as NSIP after an extended period, responds to corticosteroids, and is amenable to re-challenge at a lower-dose or with alternative BCR-ABL1 inhibitors.

Indium Lung: Discovery, Pathophysiology and Prevention.

Indium is mainly used as indium-tin oxide (ITO), which has a unique character of transparency, and is a requisite in making liquid crystal displays. Pulmonary toxicity of indium compounds in humans were not recognized until the last 2 decades. Several initial human cases of indium-related lung disease, named indium lung, were reported in Japan, with their main pathologic findings being interstitial pneumonia, emphysema and cholesterol crystals-containing granulomas. In 2010, three cases with alveolar proteinosis were reported from the United States and China. As of March 2019, more than 10 cases of interstitial pneumonia-dominant indium lung have been reported. Cross-sectional studies in indium workers indicate that the serum indium concentration (sIn) is closely related to the exposure period, the extent of interstitial as well as emphysematous changes of the lung on high-resolution computed tomography (HRCT) and serum biomarkers of interstitial pneumonia, including KL-6 and surfactant protein-D (SP-D). Longitudinal studies have shown it is possible to reduce the sIn as well as the interstitial shadows on HRCT; however, emphysematous lesions increased progressively in heavily exposed workers, even after cessation of exposure. Early detection is required to prevent irreversible changes. The first case of lung cancer associated with indium lung developed in a nonsmoking ex-worker. He had been diagnosed with indium lung and stopped working in indium processing 17 years before. This suggested there is a need for appropriate screening to detect for complications of lung cancer at early stages for those with indium lung.

Criteria for the diagnosis of idiopathic pleuroparenchymal fibroelastosis: A proposal.

BACKGROUND: Physicians have few opportunities to perform surgical lung biopsy (SLB) to diagnose idiopathic pleuroparenchymal fibroelastosis (IPPFE). Therefore, diagnostic criteria for IPPFE that do not require SLB must be established. Herein, we propose diagnostic criteria for IPPFE with and without SLB. METHODS AND RESULTS: The diagnostic criteria for IPPFE with SLB are histological, based on computed tomography (CT) lesions compatible with PPFE, predominantly in the upper lobes. The three diagnostic criteria for IPPFE without SLB are as follows: (1) radiologically possible IPPFE (a radiological criterion confirming CT lesions in both lung apexes, regardless of the lower lobe lesions); (2) radiologically probable IPPFE (also a radiological criterion, but mandatory to confirm chest radiograph findings of bilateral upward shift of the hilar structures and/or CT findings of volume loss of the upper lobes); (3) radiologically and physiologically probable IPPFE. Our data from 41 patients with IPPFE and 97 with idiopathic pulmonary fibrosis (IPF) showed that the percentage of the predicted values of the ratio of residual volume to total lung capacity (RV/TLC %pred.) ≥115% and body mass index (BMI) ≤20 kg/m2 plus RV/TLC %pred. ≥80% performed well for discriminating IPPFE from IPF. These parameters were thus added to criterion (3). CONCLUSIONS: We have proposed diagnostic criteria for IPPFE in patients with and without SLB. Both imaging criteria and physiological criteria using RV/TLC and BMI successfully discriminate IPPFE from chronic IIPs when SLB cannot be performed.

Pleuroparenchymal fibroelastosis diagnosed by multidisciplinary discussions in Japan.

BACKGROUND: Pleuroparenchymal fibroelastosis (PPFE) is a rare subset of idiopathic interstitial pneumonias. No large-scale clinical studies of PPFE have been published. The aim of the study was to clarify the clinical and physiological characteristics of PPFE in Japan METHODS: This was a retrospective, nationwide, and multicenter study in Japan. We reviewed 52 patients with PPFE, diagnosed after multidisciplinary discussions. RESULTS: Flat chest index, defined as the ratio of anteroposterior diameter to transverse diameter of thoracic cage at the level of 6th thoracic vertebra, correlated positively with body mass index (BMI) (r = 0.340, p = 0.013) and percentage of predicted value of forced vital capacity (FVC %pred) (r = 0.355, p = 0.012), and negatively with the ratio of residual volume to total lung capacity (RV/TLC) (r = -0.312, p = 0.042). RV/TLC correlated negatively with BMI (r = -0.746, p < 0.0001) and FVC %pred (r = -0.507, p = 0.0005), and positively with age, and physiological variables (GAP) scores (r = 0.332, p = 0.030). The median survival time and the cumulative 5-year survival rate were 96 months and 58%, respectively. Patients with KL-6 level >600 (U/mL) survived shorter than those with <600 (p < 0.001). CONCLUSION: Low BMI, decreased FVC and increased RV/TLC in PPFE may be related to the progression of flattened chest cage which impairs distension of chest cage at inspiration. Elevated serum levels of KL-6 suggest a poor prognosis of PPFE.

Transient Pulmonary Interstitial Lesions in Aquaporin-4-positive Neuromyelitis Optica Spectrum Disorder.

We herein report the case of a 76-year old man with aquaporin-4-Immunoglobulin-G (AQP4-IgG)-positive neuromyelitis optica spectrum disorder (NMOSD), in whom transient interstitial pulmonary lesions developed at the early stage of the disease. Chest X-ray showed multiple infiltrative shadows in both upper lung fields, and computed tomography revealed abnormal shadows distributed randomly in the lungs. Surgical lung biopsy showed features of unclassifiable interstitial pneumonia, characterized by various types of air-space organization, which resulted in obscure lung structure. This is the first report to describe the pathological findings of interstitial pneumonia, which may represent a rare extra-central nervous system complication of NMOSD.

Bilateral Tuberculous Pleurisy with Subsequent Upper Lobe Predominant Pulmonary Fibrosis Mimicking Pleuroparenchymal Fibroelastosis.

Although the majority of patients with Mycobacterium tuberculosis have pulmonary involvement, some cases have pleural involvement as extra-pulmonary sites of infection. We herein report a case of upper lobe-predominant pulmonary fibrosis that developed in a 47-year-old male with a history of bilateral tuberculous pleurisy. Based on his chest radiological findings, pleuroparenchymal fibroelastosis (PPFE) was most strongly suspected, and a surgical lung biopsy (SLB) was performed to obtain a pathological diagnosis. The SLB specimens showed interstitial pneumonia with pleural involvement without any characteristic findings of PPFE. Careful discretion in obtaining a precise diagnosis of this condition should be practiced in such cases.

Early-stage diffuse panbronchiolitis in a young patient confirmed by video-assisted lung biopsy: A case report.

A 29-year-old man presented with sputum and cough, which were pointed out by his neighbors. A high-resolution chest computed tomography scan showed well-defined multiple centrilobular nodules and a tree-in-bud pattern. Chest auscultation revealed coarse crackles. He did not report any nasal sinus symptoms. We subsequently performed a video-assisted lung biopsy; the specimen confirmed diffuse panbronchiolitis. Subsequently, sinusitis was confirmed by an otolaryngologist. His symptoms gradually improved following treatment with erythromycin. We report a case of early-stage diffuse panbronchiolitis in a young patient, with multiple intralobular nodules, no bronchiectasis, and a good clinical course.

A clinicopathological study of surgically resected lung cancer in patients with usual interstitial pneumonia.

BACKGROUND: The clinicopathological characteristics of lung cancer with concomitant usual interstitial pneumonia (UIP) are insufficiently understood. This study aimed to elucidate a characteristic pathological feature of lung cancer that develops in patients with UIP, with a focus on the location of its onset. METHODS: We reviewed surgically obtained specimens, including 547 tumors from 526 patients who underwent lobectomy for lung cancer. Surveyed patients were classified into three groups: patients with UIP (UIP group), patients with lung pathology other than UIP (non-UIP group), and patients without any associated lung pathology (normal group). The histology as well as the lobe and location of the onset of lung cancer were compared among these groups. The peripheral location was subdivided into subpleural, inner and tumor involved centrally secondary to extension. RESULTS: The UIP group comprised 82 patients (male, 71 [87%]; mean age, 71 years; smoking rate, 94%), the non-UIP group comprised 334 patients (male, 267 [80%]; mean age, 69 years; smoking rate, 81%), and the normal group comprised 110 patients (male, 33 [30%]; mean age, 63; smoking rate, 29%). No statistical differences were noted in sex, mean age, or smoking index between the UIP and non-UIP groups. Compared with the non-UIP group, the frequency of squamous cell carcinoma (63% vs. 32%), lower lobe origin (76% vs. 32%), and subpleural location (24% vs. 5%) were significantly higher in the UIP group. CONCLUSIONS: Lung cancers in patients with UIP show a predilection for the subpleural region, where UIP is also thought to originate.