Successful Treatment with High-dose Steroids for Acute Exacerbation of Idiopathic Pulmonary Fibrosis Triggered by COVID-19

The incidence of acute exacerbation of idiopathic pulmonary fibrosis: a systematic review and meta-analysis

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease with a high incidence of acute exacerbation and an increasing mortality rate. Currently, treatment methods and effects are limited. Therefore, we conducted a meta-analysis of the incidence of acute exacerbation in patients with IPF, hoping to provide reference for the prevention and management of IPF. We systematically searched the PubMed, Embase, Cochrane Library and Web of Science databases. From the creation of the database to the cohort study on April 3, 2023, we collected studies on the incidence of acute exacerbation of IPF patients, and used Stata software (version 16.0) for meta analysis. We used the Newcastle Ottawa Quality Assessment Scale (NOS) to assess the risk of bias for each study. We calculated the incidence of acute exacerbation in IPF patients and analyzed the risk factors for acute exacerbation in IPF patients and prognostic factors for overall survival from the initial IPF diagnosis. A total of ten cohort studies on the incidence of AE-IPF were included, including 11,855 IPF patients. The results showed that the incidence of acute exacerbation within one year was 9%; the incidence of acute exacerbation within 2 years is 13%; the incidence of acute exacerbation within 3 years is 19%; the incidence of acute exacerbation within 4 years is 11%. In addition, one study reported an acute exacerbation rate of 1.9% within 30 days. The incidence of acute exacerbation within ten years reported in one study was 9.8%. Mura et al.'s article included a retrospective cohort study and a prospective cohort study. The prospective cohort study showed that the incidence of acute exacerbation within 3 years was 18.6%, similar to the results of the retrospective cohort study meta-analysis. Our system evaluation and meta-analysis results show that the incidence of AE-IPF is relatively high. Therefore, sufficient attention should be paid to the research results, including the management and prevention of the disease, in order to reduce the risk of AE.Trial registration: PROSPERO, identifier CRD42022341323.

Animal models of acute exacerbation of pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive scarring interstitial lung disease with an unknown cause. Some patients may experience acute exacerbations (AE), which result in severe lung damage visible on imaging or through examination of tissue samples, often leading to high mortality rates. However, the etiology and pathogenesis of AE-IPF remain unclear. AE-IPF patients exhibit diffuse lung damage, apoptosis of type II alveolar epithelial cells, and an excessive inflammatory response. Establishing a reliable animal model of AE is critical for investigating the pathogenesis. Recent studies have reported a variety of animal models for AE-IPF, each with its own advantages and disadvantages. These models are usually established in mice with bleomycin-induced pulmonary fibrosis, using viruses, bacteria, small peptides, or specific drugs. In this review, we present an overview of different AE models, hoping to provide a useful resource for exploring the mechanisms and targeted therapies for AE-IPF.

COVID-19 and interstitial lung diseases: A multifaceted look at the relationship between the two diseases

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although it has been a fatal disease for many patients, the development of treatment strategies and vaccines have progressed over the past 3 years, and our society has become able to accept COVID-19 as a manageable common disease. However, as COVID-19 sometimes causes pneumonia, post-COVID pulmonary fibrosis (PCPF), and worsening of preexisting interstitial lung diseases (ILDs), it is still a concern for pulmonary physicians. In this review, we have selected several topics regarding the relationships between ILDs and COVID-19. The pathogenesis of COVID-19-induced ILD is currently assumed based mainly on the evidence of other ILDs and has not been well elucidated specifically in the context of COVID-19. We have summarized what has been clarified to date and constructed a coherent story about the establishment and progress of the disease. We have also reviewed clinical information regarding ILDs newly induced or worsened by COVID-19 or anti-SARS-CoV-2 vaccines. Inflammatory and profibrotic responses induced by COVID-19 or vaccines have been thought to be a risk for de novo induction or worsening of ILDs, and this has been supported by the evidence obtained through clinical experience over the past 3 years. Although COVID-19 has become a mild disease in most cases, it is still worth looking back on the above-reviewed information to broaden our perspectives regarding the relationship between viral infection and ILD. As a representative etiology for severe viral pneumonia, further studies in this area are expected.

COVID-19 in Patients with Pre-Existing Interstitial Lung Disease: Potential Value of a Steroid-Based Treatment Strategy

The prognosis of patients with coronavirus disease 2019 (COVID-19) and pre-existing interstitial lung disease (preILD) is poor, and no effective treatment strategy has been determined. The aim of this study was to assess the effectiveness of a steroid-based treatment strategy for patients with COVID-19 and preILD. We retrospectively reviewed the medical records of 610 consecutive patients with COVID-19 treated at our institution between 1 March 2020 and 30 October 2021 and identified 7 patients with preILD, all of whom were treated with corticosteroids and remdesivir. All the patients were men with a median age of 63 years. Three of four patients with severe disease required invasive positive-pressure ventilation (n = 2) or nasal high-flow therapy (n = 1). All three patients could be weaned from respiratory support; however, one died in hospital. The remaining patient with severe COVID-19 had a do-not-resuscitate order in place and died while hospitalized. All three patients with moderate COVID-19 were discharged. The 30-day mortality was 0%, and the mortality rate during the entire observation period was 28.5%. The prognosis of our patients with COVID-19 and preILD has been better than in previous reports. Our management strategy using corticosteroids may have improved these patients' prognosis.

[SARS-CoV-2-Infection and Interstitial Lung Disease: Position paper of the German Respiratory Society]

The SARS-CoV-2 pandemic had a tremendous impact on diagnosis and treatment of interstitial lung diseases (ILD). Especially in the early phase of the pandemic, when the delta variant was prevailling, a huge number of viral pneumonias were observed, which worsened pre-existing, triggered de novo occurence or discovery of previously subclincal interstitial lung diseases. The effect of SARS-CoV-2 infection - without or with accompanying viral pneumonia - on the further development of pre-existing ILD as well of new pulmonary inflitrates and consolidiations is difficult to predict and poses a daily challenge to interdisciplinary ILD boards. This position paper of the German Respiratory Society (DGP e.V.) provides answers to the most pressing questions based on current knowledge.

Acute exacerbation of rheumatoid arthritis-associated interstitial lung disease triggered by COVID-19: What is the best practice for treatment?

We present a case of 79-year-old female with rheumatoid arthritis-associated interstitial lung disease (RA-ILD) developed an acute exacerbation (AE) triggered by coronavirus disease 2019 (COVID-19). The patient was unresponsive to a combination therapy of remdesivir, dexamethasone, and tocilizumab. Given that a recent multicenter cohort study reported ILD as a poor prognostic contributor in patients with RA and COVID-19, there may be potentially a certain number of patients with AE of RA-ILD triggered by COVID-19. This case highlights the need for a discussion how to treat these patients in a daily clinical practice.

COVID-19-Triggered Acute Exacerbation of IPF, an Underdiagnosed Clinical Entity With Two-Peaked Respiratory Failure: A Case Report and Literature Review

Because severe coronavirus disease 2019 (COVID-19) affects the respiratory system and develops into respiratory failure, patients with pre-existing chronic lung disorders, such as idiopathic pulmonary fibrosis (IPF), are thought to be at high risk of death. Patients with IPF often suffer from a lethal complication, acute exacerbation (AE), a significant part of which is assumed to be triggered by respiratory viral infection. However, whether mild to moderate COVID-19 can trigger AE in patients with IPF remains unknown. This is the case report of a 60-year-old man with a 4-year history of IPF who successfully recovered from moderate COVID-19 but subsequently developed more severe respiratory failure, which was considered to be a COVID-19-triggered acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF). It is important to be aware of the risk of AE-IPF after COVID-19 and to properly manage this deadly complication of IPF. Recent literature reporting cases with chronic interstitial lung diseases which developed respiratory failure by complications with COVID-19 is also reviewed and discussed.