While idiopathic interstitial pneumonia (IIP) centering on idiopathic pulmonary fibrosis (IPF) is the most prevalent interstitial lung disease (ILD), especially in the older adult population, connective tissue disease (CTD)-related ILD is the second most prevalent ILD. The pathogenesis of IPF is primarily fibrosis, whereas that of other ILDs, particularly CTD-ILD, is mainly inflammation. Therefore, a precise diagnosis is crucial for selecting appropriate treatments, such as antifibrotic or immunosuppressive agents. In addition, some patients with IIP have CTD-related features, such as arthritis and skin eruption, but do not meet the criteria for any CTD, this is referred to as interstitial pneumonia with autoimmune features (IPAF). IPAF is closely associated with idiopathic nonspecific interstitial pneumonia (iNSIP) and cryptogenic organizing pneumonia (COP). Furthermore, patients with iNSIP or those with NSIP with OP overlap frequently develop polymyositis/dermatomyositis after the diagnosis of IIP. Acute exacerbation of ILD, the most common cause of death, occurs more frequently in patients with IPF than in those with other ILDs. Although acute exacerbation of CTD-ILD occurs at a low rate of incidence, patients with rheumatoid arthritis, microscopic polyangiitis, or systemic sclerosis experience more acute exacerbation of CTD-ILD than those with other CTD. In this review, the features of each IIP, focusing on CTD-related signatures, are summarized, and the pathogenesis and appropriate treatments to improve the prognoses of patients with various ILDs are discussed.

BACKGROUND: Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) increases mortality risk, but which factors increase mortality is unknown. We aimed to perform a prognostic review of factors associated with mortality in patients with IPF.
METHODS: and methods: We searched MEDLINE, EMBASE, and CINAHL for studies that reported on the association between any prognostic factor and AE-IPF. We assessed risk of bias using the QUIPS tool. We conduced pairwise meta-analyses using REML heterogeneity estimator, and GRADE approach to assess the certainty of the evidence.
RESULTS: We included 35 studies in our analysis. We found that long-term supplemental oxygen at baseline (aHR 2.52 [95 % CI 1.68 to 3.80]; moderate certainty) and a diagnosis of IPF compared to non-IPF ILD (aHR 2.19 [95 % CI 1.22 to 3.92]; moderate certainty) is associated with a higher risk of death in patients with AE-IPF. A diffuse pattern on high resolution computed tomography (HRCT) compared to a non-diffuse pattern (aHR 2.61 [95 % CI 1.32 to 2.90]; moderate certainty) is associated with a higher risk of death in patients with AE-IPF. We found that using corticosteroids prior to hospital admission (aHR 2.19 [95 % CI 1.26 to 3.82]; moderate certainty) and those with increased neutrophils (by % increase) in bronchoalveolar lavage (BAL) during the exacerbation is associated with a higher risk of death (aHR 1.02 [1.01 to 1.04]; moderate certainty).
CONCLUSIONS: Our results have implications for healthcare providers in making treatment decisions and prognosticating the clinical trajectory of patients, for researchers to design future interventions to improve patient trajectory, and for guideline developers in making decisions about resource allocation.

PurposeThis article is an in-depth review of the complex classification, diagnosis, and treatment of idiopathic interstitial pneumonias (IIP), as well as emergence of new treatment options. Summary: Idiopathic interstitial pneumonias consist of various subgroup classifications that require expert analysis of imaging and histology to accurately diagnose this broad group of patients. Timely and accurate assessment of these patients is key in developing an appropriate pharmacological plan. The pathophysiology of IIP is not well understood but has been linked to an immune response resulting in inflammation, fibrosis, or proliferation of lung tissue which reduces lung function. Lung transplantation is currently the only curative option for treatment, but many new antiproliferative and immunosuppressive agents are being used to effectively slow the progression of lung dysfunction. Conclusion: An often mixed radiological and histological pattern along with the invasive nature of biopsy for gold standard diagnosis create a challenge for the accurate identification of IIP. Further understanding of these idiopathic interstitial pneumonias will pave the way forward to the emergence of new treatment options and updates to standards of care.

COVID-19 pneumonia represents a challenging health emergency, due to the disproportion between the high transmissibility, morbidity, and mortality of the virus and healthcare systems possibilities. Literature has mainly focused on COVID-19 pneumonia clinical-radiological diagnosis and therapy, and on the most common differential diagnoses, while few papers investigated rare COVID-19 pneumonia differential diagnoses or the overlapping of COVID-19 pneumonia on pre-existing lung pathologies. This article presents the main radiological characteristics of COVID-19 pneumonia and Idiopathic Interstitial Pneumonias (IIPs) to identify key radiological features for a differential diagnosis among IIPs, and between IIPs and COVID-19 pneumonia. COVID-19 pneumonia differential diagnosis with IIPs is challenging, since these entities may share common radiological findings as ground glass opacities, crazy paving patterns, and consolidations. Multidisciplinary discussion is crucial to reach a final and correct diagnosis. Radiologists have a pivotal role in identifying COVID-19 pneumonia patterns, reporting possible overlapping with long-lasting lung diseases, and suggesting potential differential diagnoses. An optimal evaluation of HRTC may help in containing the disease, in promoting better treatment for patients, and in providing an efficient allocation of human and economic resources.

BACKGROUND: Desquamative Interstitial Pneumonia (DIP) is a rare form of idiopathic interstitial pneumonia (IIP). Data on clinical features, aetiology, prognosis and effect of treatment strategies are limited. We aimed to collect all published cases to better characterise DIP.
METHODS: A systematic literature search was performed for all original cases of adult patients with histopathologically-confirmed DIP. Individual patient data were extracted and summarised.
RESULTS: We included 68 individual cases and 13 case series reporting on 294 cases. Most common presenting symptoms were dyspnoea and cough. Pulmonary function showed a restrictive pattern (71%) with decreased diffusion capacity. We found a high incidence (81%) of ever smoking in patients with DIP and 22% of patients had other (occupational) exposures. Characteristic features on high-resolution computed tomography (HRCT) scan were bilateral ground-glass opacities with lower lobe predominance (92%). Treatment and duration of treatment widely varied. Initial response to treatment was generally good, but definitely not uniformly so. A significant proportion of patients died (25% of individual cases) or experienced a relapse (18% of individual cases).
CONCLUSIONS: DIP remains an uncommon disease, frequently but not always related to smoking or other exposures. Furthermore, DIP behaves as a progressive disease more often than generally thought, possibly associated with different underlying aetiology.

Objective: To analyze the clinical,imaging and pathological features of Pleuroparenehymal fibroelastosis (PPFE). Methods: The clinieal data of a patient diagnosed as PPFE admitted in department of Respiratory and Critical Care Medicine,Beijing Hospital in April 2017 were reported and the related literatures were reviewed.With \"pleuroparenehymal fibroelastosis\" as the search terms, and the search time before October 1st 2017 for Wanfangdata, China National Knowledge Infrastructure(CNKI), and PubMed. Results: The patient was a 46-year-old male presented with cough, shortness of breath after exercise.A CT scan of the chest revealed bilateral, irregular pleural thickening with upper lobe predominance.After 3 years of antituberculosis treatment,the disease progressed. A diagnosis of pleuroparenehymal fibroelastosis (PPFE) was confirmed by CT guided lung biopsy. A total of 132 cases were reported (including 1 case in Chinese). 88 of them were confirmed by pathology with detailed data.Clinical data of 89 reported cases with PPFE including 48 males and 41 females aged 13 to 85 years were enrolled and analyzed in the study.The common symptoms were dyspnea(62%, 55 cases),cough(58%, 52 cases),recurrent respiratory tract infection(17%, 15 cases).The main CT features are reported:pleural thickening(87%,77 cases), recurrent pneumothorax(52%,46 cases), traction bronchiectasis(30%, 27 cases),subpleural comsolidation(20%, 18 cases). All patients were proven PPFE by biopsy.34 cases received corticosteroid, 5 cases received lung transplant operation.40 cases died during the follow-up from 4 month to 84 month. Conclusions: Pleuroparenehymal fibroelastosis is a rare disease.The imaging findings were dominated by both upper lobes. Lung biopsy might be necessary. PPFE is often misdiagnosed as pulmonary tuberculosis/obsolete pulmonary tuberculosis,asbestosis,connective tissues disease and Drug-induced pneumonitis.There was no consensus on the treatment.
目的： 总结分析胸膜肺弹力纤维增生症（pleuroparenehymal fibroelastosis，PPFE）患者的临床、影像和病理学特点，提高临床诊治水平。 方法： 回顾性分析北京医院收治的1例病理诊断的PPFE患者的临床资料，并进行相关文献复习。以\"胸膜肺弹力纤维增生症\"为检索词，检索万方数据库和同方期刊数据库；以\"pleuroparenehymal fibroelastosis\"为检索词，检索PubMed数据库，检索2017年10月之前报道的所有中文和英文文献。 结果： 患者男，46岁，咳嗽、活动后气短。胸部CT示双上胸廓变小，双肺尖胸膜增厚并胸膜下实变影，伴牵引性支气管扩张。曾反复抗结核治疗,疗程共3年，病情进展。行CT引导下肺穿刺，病理结果示胸膜肺弹力纤维增生症。文献复习共检索到国内外病例132例（其中中文文献报道1例），其中88例由病理确诊且资料详实。结合本例共纳入89例，男48例，女41例，年龄13~85岁，平均（50±17）岁。常见的症状为呼吸困难55例（62%），咳嗽52例（58%），反复呼吸道感染15例（17%）。胸部影像学表现为胸膜增厚77例（87%），反复气胸46例（52%），牵张性支气管扩张27例（30%），胸膜下实变影18例（20%）。89例均经组织活检病理确诊。34例接受糖皮质激素治疗，5例行肺移植。89例患者随访时间为4~84个月，随访期间40例因疾病进展死亡。 结论： 胸膜肺弹力纤维增生症是一种少见病，病变以双上肺为主，确诊要依据病理。临床需与肺结核或陈旧性肺结核、石棉肺、结缔组织疾病相关性肺病及药物性肺损伤鉴别。治疗方案尚未达成共识。该病预后不佳。.

We clarify clinical characteristics of patients with immune checkpoint inhibitor (ICI)-induced myositis.
In 13 of 15 cases with ICI-induced myositis, the type of malignancy was melanoma. Eight, 4, and 3 patients received anti-PD-1 alone, anti-CTLA4 alone, and a combination of those, respectively. The mean period to the onset of ICI-induced myositis from the initiation of ICI was 4 weeks. Myocarditis was a complication in five patients. Seven of the patients died. The causes of death were myocarditis in three patients, respiratory muscle paralysis in two patients, and cancer progression in two patients. In patients without myocarditis or respiratory muscle paralysis, the prognosis for myositis was favorable with normalization of the CK levels occurring upon the cessation of ICI and the administration of immunosuppressive agents. Myocarditis and respiratory muscle paralysis are the major causes of death as immune-related adverse events in patients with ICI-induced myositis.

Acute fibrinous and organizing pneumonia is a histopathologic entity of lung injury with the hallmark feature of intra-alveolar fibrin \"balls.\" We report 2 cases of acute fibrinous and organizing pneumonia in patients without a significant medical history, who presented with cough and worsening dyspnea and experienced a fulminant course of disease progression with diffuse lung parenchymal abnormalities on chest computed tomography. These cases suggest that this rare histologic pattern of idiopathic interstitial pneumonias can be included in the differential diagnosis with other conditions leading to acute respiratory failure.

Fibrotic interstitial pneumonias are a group of rare diseases characterised by distortion of lung interstitium. Patients with mutations in surfactant-processing genes, such as surfactant protein C (SFTPC), surfactant protein A1 and A2 (SFTPA1 and A2), ATP binding cassette A3 (ABCA3) and Hermansky-Pudlak syndrome (HPS1, 2 and 4), develop progressive pulmonary fibrosis, often culminating in fatal respiratory insufficiency. Although many mutations have been described, little is known about the optimal treatment strategy for fibrotic interstitial pneumonia patients with surfactant-processing mutations.We performed a systematic literature review of studies that described a drug effect in patients, cell or mouse models with a surfactant-processing mutation. In total, 73 articles were selected, consisting of 55 interstitial lung disease case reports/series, two clinical trials and 16 cell or mouse studies. Clinical effect parameters included lung function, radiological characteristics and clinical symptoms, while experimental outcome parameters included chemokine/cytokine expression, surfactant trafficking, necrosis and apoptosis. SP600125, a c-jun N-terminal kinase (JNK) inhibitor, hydroxychloroquine and 4-phenylbutyric acid were most frequently studied in disease models and lead to variable outcomes, suggesting that outcome is mutation dependent.This systematic review summarises effect parameters for future studies on surfactant-processing disorders in disease models and provides directions for future trials in affected patients.

Pleuroparenchymal fibroelastosis (PPFE) is now a defined clinicopathologic entity in the updated 2013 ATS/ERS classification of idiopathic interstitial pneumonias (IIPs), which has led to a significant increase in cases being diagnosed at our institution. We have therefore reviewed 43 PPFE cases (58 biopsies in total) to assess whether any clinical or histopathologic features provide prognostic information. A semiquantatitive grading system was used to assess extent of fibroblastic foci, intra-alveolar fibroelastosis, visceral pleural fibrosis, chronic inflammation in areas of fibrosis, vascular fibrointimal thickening, and presence of granulomas. Other patterns of interstitial lung disease were also noted, if present. All biopsies showed intra-alveolar fibroelastosis, fibroblastic foci at the leading edge of fibrosis and chronic inflammation within areas of fibrosis, 91% showed vascular fibrointimal thickening of vessels, 73% showed pleural fibrosis, and 35% showed granulomas. Ten cases showed a coexistent IIP (5 showed usual interstitial pneumonia, 5 showed features of hypersensitivity pneumonitis). There was no significant correlation with mortality and severity of histologic parameters, other than a significant decrease in mortality in PPFE with coexistent granulomas, after adjusting for age and gender (hazard ratio, 0.27; P=0.049). Male gender was also associated with an increased risk of mortality, after adjusting for age (hazard ratio, 4.8; P=0.045). PPFE is more common than previously thought, not infrequently showing coexistent pathology, specifically usual interstitial pneumonia and granulomatous lung disease, our data suggesting the latter may have prognostic significance.