The Role of Pulmonary Surfactant Phospholipids in Fibrotic Lung Diseases.

Diffuse parenchymal lung diseases (DPLD) or Interstitial lung diseases (ILD) are a heterogeneous group of lung conditions with common characteristics that can progress to fibrosis. Within this group of pneumonias, idiopathic pulmonary fibrosis (IPF) is considered the most common. This disease has no known cause, is devastating and has no cure. Chronic lesion of alveolar type II (ATII) cells represents a key mechanism for the development of IPF. ATII cells are specialized in the biosynthesis and secretion of pulmonary surfactant (PS), a lipid-protein complex that reduces surface tension and minimizes breathing effort. Some differences in PS composition have been reported between patients with idiopathic pulmonary disease and healthy individuals, especially regarding some specific proteins in the PS; however, few reports have been conducted on the lipid components. This review focuses on the mechanisms by which phospholipids (PLs) could be involved in the development of the fibroproliferative response.

Anti-synthetase syndrome masquerading as recurrent pneumonia.

Anti-synthetase syndrome (ASS) is a rare inflammatory myopathy with a wide variety of clinical presentations. ASS-related interstitial lung disease (ASS-ILD) presents with rapid onset and progression, which could often be confused with other more common acute processes such as pneumonia, especially when ILD can be the sole manifestation. A woman in her 50s presented with recurrent dyspnoea for 2 months requiring multiple hospital admissions, and each time, she was diagnosed with multifocal pneumonia and treated with antibiotics. On admission, the evaluation revealed a markedly elevated creatine kinase level at 3258 U/L and a CT scan of the chest revealed worsening scattered ground-glass opacities. Given the concern for ILD as the cause of antibiotic failure, she underwent bronchoscopy with bronchoalveolar lavage which revealed non-specific interstitial pneumonia. A subsequent myositis panel revealed a positive anti-Jo-1 antibody, and she was diagnosed with ASS-ILD. She completed a course of intravenous immunoglobulin and methylprednisolone and experienced significant clinical improvement with the resolution of hypoxaemia and improved polyarthralgia.ASS could often be misdiagnosed as other more common acute lung processes, as a clinically subtle course can escape detection given its rarity, as well as its non-specific and highly variable presentations. This case highlights the importance of early suspicion and consideration of performing specific autoantibody testing when evaluating patients with a suspicion of undifferentiated autoimmune condition.

Tofacitinib treatment in anti-glycyl-tRNA synthetase antibody interstitial lung disease - A case report.

Anti-aminoacyl-transfer-RNA synthetase syndrome (ASS) related interstitial lung disease (ILD) is rarely presented initially alongside acute respiratory distress syndrome (ARDS), which in and of itself is a severe condition with a high mortality rate. Additionally, rapidly progressive change is not a common feature in ASS. Numerous case reports have described the efficacy which tofacitinib has on rapidly progressive ILD (RP-ILD). However, none have mentioned the use of tofacitinib in patients with impaired renal function. Herein, a case of ASS involving ILD is reported with the initial presentation of RP-ILD to ARDS being complicated by acute renal failure with an initial complete response to tofacitinib. Patients experiencing unexplained rapidly progressive interstitial pneumonia should be examined thoroughly for the diagnosis of ASS. Furthermore, tofacitinib can also be considered as a choice of treatment even in patients with impaired renal function.

Progressive interstitial lung disease in hypomyopathic dermatomyositis in the COVID-19 pandemic: A case report.

BACKGROUND: Clinically amyopathic dermatomyositis (CADM) is characterized by typical skin lesions with no (amyopathic) or subclinical (hypomyopathic) evidence of muscle involvement. Patients with CADM may also develop rapidly progressive interstitial lung disease (ILD), and have a poor prognosis. However, the diagnosis of rapidly progressive ILD faces a challenge during the severe acute respiratory syndrome coronavirus 2 pandemic. Severe acute respiratory syndrome and ground-glass attenuation on a chest computed tomography scan are the presenting features in both conditions. CASE PRESENTATION: A 45-year-old woman with amyopathic dermatomyositis had acute onset of fever and dyspnea in February 2020. She had abnormal lung findings on CT scan. Polymerase chain reaction testing for SARS-CoV-2 was not available at that time. Chest CT revealed non-specific manifestations that could be either the signs of ILD or SARS-CoV-2 infection. Antiviral therapy was initiated with oseltamivir. Three days later, she had erythema on face, palm, and back. The ratio of lactate dehydrogenase (LDH) isoenzyme 3 to total LDH was elevated. The ratio of LDH isoenzyme 1 to total LDH was declined. Therefore, she was transferred to the rheumatology ward for further treatment. However, she died from respiratory failure 2 weeks later. CONCLUSIONS: We speculate that the altered LDH isoenzyme pattern may be an early biomarker for co-occurrence of CADM and ILD.

Interstitial lung disease following coronavirus disease 2019.

PURPOSE OF REVIEW: The aim of this review was to summarize the recent data concerning interstitial lung disease after COVID-19, a field where knowledge is evolving very quickly. RECENT FINDINGS: It has been found that a proportion of patients displayed fibrotic-like pattern on chest computed tomography shortly after COVID-19 pneumonia. Those lesions can potentially represent precursors of fibrosis, although most of them will resolve until 1 year postinfection. There was a wide range of the prevalence of post-COVID-19 interstitial lung disease detected in the literature, which can be attributed to the heterogeneous definition of lung abnormalities and the discrepancy of study design. The severity of acute COVID-19 disease has been linked to increased risk of residual imaging and functional abnormalities, while reduced DLco was the most common functional abnormality in long-term survivors. Studies indicated that pathophysiology of post-COVID interstitial lung disease shares common mechanisms with idiopathic pulmonary fibrosis. Regarding therapeutic strategies of post-COVID-19 interstitial lung disease, the role of immunosuppressive and antifibrotic treatment is currently under investigation. SUMMARY: We still need to learn about the natural history of COVID-19 disease, allowing for a better targeting of therapeutic interventions through a multidisciplinary approach.

A review of the challenges, learnings and future directions of home handheld spirometry in interstitial lung disease.

BACKGROUND: Patients with interstitial lung disease (ILD) require regular physician visits and referral to specialist ILD clinics. Difficulties or delays in accessing care can limit opportunities to monitor disease trajectory and response to treatment, and the COVID-19 pandemic has added to these challenges. Therefore, home monitoring technologies, such as home handheld spirometry, have gained increased attention as they may help to improve access to care for patients with ILD. However, while several studies have shown that home handheld spirometry in ILD is acceptable for most patients, data from clinical trials are not sufficiently robust to support its use as a primary endpoint. This review discusses the challenges that were encountered with handheld spirometry across three recent ILD studies, which included home spirometry as a primary endpoint, and highlights where further optimisation and research into home handheld spirometry in ILD is required. Rate of decline in forced vital capacity (FVC) as measured by daily home handheld spirometry versus site spirometry was of primary interest in three recently completed studies: STARLINER (NCT03261037), STARMAP and a Phase II study of pirfenidone in progressive fibrosing unclassifiable ILD (NCT03099187). Unanticipated practical and technical issues led to problems with estimating FVC decline. In all three studies, cross-sectional correlations for home handheld versus site spirometry were strong/moderate at baseline and later timepoints, but longitudinal correlations were weak. Other issues observed with the home handheld spirometry data included: high within-patient variability in home handheld FVC measurements; implausible longitudinal patterns in the home handheld spirometry data that were not reflected in site spirometry; and extreme estimated rates of FVC change. CONCLUSIONS: Home handheld spirometry in ILD requires further optimisation and research to ensure accurate and reliable FVC measurements before it can be used as an endpoint in clinical trials. Refresher training, automated alerts of problems and FVC changes, and patient support could help to overcome some practical issues. Despite the challenges, there is value in incorporating home handheld spirometry into clinical practice, and the COVID-19 pandemic has highlighted the potential for home monitoring technologies to help improve access to care for patients with ILD.

Human MIKO-1, a Hybrid Protein That Regulates Macrophage Function, Suppresses Lung Fibrosis in a Mouse Model of Bleomycin-Induced Interstitial Lung Disease.

Although interstitial lung disease (ILD) is a life-threatening pathological condition that causes respiratory failure, the efficiency of current therapies is limited. This study aimed to investigate the effects of human MIKO-1 (hMIKO-1), a hybrid protein that suppresses the abnormal activation of macrophages, on murine macrophage function and its therapeutic effect in a mouse model of bleomycin-induced ILD (BLM-ILD). To this end, the phenotype of thioglycolate-induced murine peritoneal macrophages co-cultured with hMIKO-1 was examined. The mice were assigned to normal, BLM-alone, or BLM + hMIKO-1 groups, and hMIKO-1 (0.1 mg/mouse) was administered intraperitoneally from day 0 to 14. The mice were sacrificed on day 28, and their lungs were evaluated by histological examination, collagen content, and gene expression levels. hMIKO-1 suppressed the polarization of murine macrophages to M2 predominance in vitro. The fibrosis score of lung pathology and lung collagen content of the BLM + hMIKO-1 group were significantly lower than those in the BLM-alone group. The expression levels of TNF-α, IL-6, IL-1ß, F4/80, and TIMP-1 in the lungs of the BLM + hMIKO-1 group were significantly lower than those in the BLM-alone group. These findings indicate that hMIKO-1 reduces lung fibrosis and may be a future therapeutic candidate for ILD treatment.

Humoral response among patients with interstitial lung disease vaccinated with the BNT162b2 SARS-Cov-2 vaccine: a prospective cohort study.

BACKGROUND: Patients with interstitial lung disease (ILD) are at high risk of severe COVID-19 infection. Additionally, their anti-inflammatory and antifibrotic treatment may cause immunosuppression. Nevertheless, their ability to mount an adequate immune response to messenger RNA SARS-CoV-2 vaccines was not evaluated. Therefore, we aimed to evaluate the humoral response after the BNT162b2 vaccine among idiopathic pulmonary fibrosis (IPF) patients treated with antifibrotic therapy and among non-IPF ILD patients treated with anti-inflammatory therapy. METHODS: We conducted an observational prospective cohort study to evaluate the level of anti-spike (S-IgG) antibodies after two doses of the BNT162b2 vaccine in patients with ILD. The cohort included 40 patients with idiopathic pulmonary fibrosis (IPF) treated with anti-fibrotic therapy and 29 patients with non-IPF ILD treated with anti-inflammatory therapy. For S-IgG titer measurement, one serology test was drawn from all patients 4-6 months after the second vaccine dose. In addition a control group matched for age and sex was created from a healthy control cohort of 107 patients. The study was conducted in Rabin Medical Center (Israel) between June and August 2021. RESULTS: All patients in the anti-fibrotic arm were seropositive (40/40), corresponding to the matched control group (P = 1.0). The anti-fibrotic arm had a significantly lower median antibody titer in comparison to the matched control group (361.10 [IQR, 207-811] AU/ml vs. 820.75 [IQR, 459-1313] AU/ml; P < 0.001). Only 48.3% (14/29) of patients in the anti-inflammatory arm were seropositive in comparison to 100% (29/29) in the healthy control group (P < 0.001). The anti-inflammatory arm had a significantly lower median antibody titer in comparison to the healthy control group (39.6 [IQR, 4.25-165] AU/ml vs. 970.1 [IQR, 505-1926] AU/ml; P < 0.001). CONCLUSION: IPF patients treated with antifibrotic therapy mount an adequate immune response after 2 doses of the BNT162b2 vaccine, and maintain a 100% seropositivity rate 4-6 months after vaccination. However, their antibody titer was reduced in comparison to a healthy control group. Among patients with non-IPF ILD treated with anti-inflammatory therapy, 48% were seronegative 4-6 months after the second vaccine dose. Moreover, treatment with rituximab caused significant immunosuppression, even in comparison to other anti-inflammatory treatments.

Pneumocystis jirovecii Pneumonia Associated with COVID-19 in Patients with Interstitial Pneumonia.

Here, we report two cases of patients with interstitial pneumonia (IP) on steroids who developed Pneumocystis jirovecii pneumonia (PJP) following coronavirus disease 2019 (COVID-19) infection. Case 1: A 69-year-old man on 10 mg of prednisolone (PSL) daily for IP developed new pneumonia shortly after his COVID-19 infection improved and was diagnosed with PJP based on chest computed tomography (CT) findings and elevated serum ß-D-glucan levels. Trimethoprim-sulfamethoxazole (TMP-SMZ) was administered, and the pneumonia resolved. Case 2: A 70-year-old woman taking 4 mg/day of PSL for IP and rheumatoid arthritis developed COVID-19 pneumonia, which resolved mildly, but her pneumonia flared up and was diagnosed as PJP based on CT findings, elevated ß-D-glucan levels, and positive polymerase chain reaction for P. jirovecii DNA in the sputum. The autopsy revealed diffuse alveolar damage, increased collagen fiver and fibrotic foci, mucinous component accumulation, and the presence of a P. jirovecii cyst. In conclusion, steroids and immunosuppressive medications are well-known risk factors for PJP. Patients with IP who have been taking these drugs for a long time are frequently treated with additional steroids for COVID-19; thus, PJP complications should be avoided in such cases.

Randomized controlled phase 2 trial of hydroxychloroquine in childhood interstitial lung disease.

BACKGROUND: No results of controlled trials are available for any of the few treatments offered to children with interstitial lung diseases (chILD). We evaluated hydroxychloroquine (HCQ) in a phase 2, prospective, multicentre, 1:1-randomized, double-blind, placebo-controlled, parallel-group/crossover trial. HCQ (START arm) or placebo were given for 4 weeks. Then all subjects received HCQ for another 4 weeks. In the STOP arm subjects already taking HCQ were randomized to 12 weeks of HCQ or placebo (= withdrawal of HCQ). Then all subjects stopped treatment and were observed for another 12 weeks. RESULTS: 26 subjects were included in the START arm, 9 in the STOP arm, of these four subjects participated in both arms. The primary endpoint, presence or absence of a response to treatment, assessed as oxygenation (calculated from a change in transcutaneous O2-saturation of ≥ 5%, respiratory rate ≥ 20% or level of respiratory support), did not differ between placebo and HCQ groups. Secondary endpoints including change of O2-saturation ≥ 3%, health related quality of life, pulmonary function and 6-min-walk-test distance, were not different between groups. Finally combining all placebo and all HCQ treatment periods did not identify significant treatment effects. Overall effect sizes were small. HCQ was well tolerated, adverse events were not different between placebo and HCQ. CONCLUSIONS: Acknowledging important shortcomings of the study, including a small study population, the treatment duration, lack of outcomes like lung function testing below age of 6 years, the small effect size of HCQ treatment observed requires careful reassessments of prescriptions in everyday practice (EudraCT-Nr.: 2013-003714-40, www.clinicaltrialsregister.eu , registered 02.07.2013). Registration The study was registered on 2 July 2013 (Eudra-CT Number: 2013-003714-40), whereas the approval by BfArM was received 24.11.2014, followed by the approval by the lead EC of the University Hospital Munich on 20.01.2015. At clinicaltrials.gov the trial was additionally registered on November 8, 2015 (NCT02615938).

Prevalence and Death Rate of COVID-19 in Autoimmune Systemic Diseases in the First Three Pandemic Waves. Relationship with Disease Subgroups and Ongoing Therapies.

OBJECTIVE: Autoimmune systemic diseases (ASD) represent a predisposing condition to COVID-19. Our prospective, observational multicenter telephone survey study aimed to investigate the prevalence, prognostic factors, and outcomes of COVID-19 in Italian ASD patients. METHODS: The study included 3,918 ASD pts (815 M, 3103 F; mean age 59±12SD years) consecutively recruited between March 2020 and May 2021 at the 36 referral centers of COVID-19 and ASD Italian Study Group. The possible development of COVID-19 was recorded by means of a telephone survey using a standardized symptom assessment questionnaire. RESULTS: ASD patients showed a significantly higher prevalence of COVID-19 (8.37% vs. 6.49%; p<0.0001) but a death rate statistically comparable to the Italian general population (3.65% vs. 2.95%). Among the 328 ASD patients developing COVID-19, 17% needed hospitalization, while mild-moderate manifestations were observed in 83% of cases. Moreover, 12/57 hospitalized patients died due to severe interstitial pneumonia and/or cardiovascular events; systemic sclerosis (SSc) patients showed a significantly higher COVID-19-related death rate compared to the general population (6.29% vs. 2.95%; p=0.018). Major adverse prognostic factors to develop COVID-19 were: older age, male gender, SSc, pre-existing ASD-related interstitial lung involvement, and long-term steroid treatment. Of note, patients treated with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) showed a significantly lower prevalence of COVID-19 compared to those without (3.58% vs. 46.99%; p=0.000), as well as the SSc patients treated with low dose aspirin (with 5.57% vs. without 27.84%; p=0.000). CONCLUSION: During the first three pandemic waves, ASD patients showed a death rate comparable to the general population despite the significantly higher prevalence of COVID-19. A significantly increased COVID-19- related mortality was recorded in only SSc patients' subgroup, possibly favored by preexisting lung fibrosis. Moreover, ongoing long-term treatment with csDMARDs in ASD might usefully contribute to the generally positive outcomes of this frail patients' population.

Multidisciplinary clinical guidance on trastuzumab deruxtecan (T-DXd)-related interstitial lung disease/pneumonitis-Focus on proactive monitoring, diagnosis, and management.

Trastuzumab deruxtecan (T-DXd; DS-8201) is an antibody-drug conjugate targeting human epidermal growth factor receptor 2. Interstitial lung disease (ILD)/pneumonitis is an adverse event associated with T-DXd; in most cases, it is low grade (grade ≤ 2) and can be treated effectively but may develop to be fatal in some instances. It is important to increase patient and provider understanding of T-DXd-related ILD/pneumonitis to improve patient outcomes. Drug-related ILD/pneumonitis is a diagnosis of exclusion; other possible causes of lung injury/imaging findings must be ruled out for an accurate diagnosis. Symptoms can be nonspecific, and identifying early symptoms is challenging; therefore, diagnosis is often delayed. We reviewed characteristics of patients who developed T-DXd-related ILD/pneumonitis and its patterns, produced multidisciplinary guidelines on diagnosis and management, and described areas for future investigation. Ongoing studies are collecting data on T-DXd-related ILD/pneumonitis to further our understanding of its clinical patterns and mechanisms. SEARCH STRATEGY AND SELECTION CRITERIA: References were identified based on the guidelines used by the authors in treating interstitial lung disease and pneumonitis. Searches of the authors' own files were also completed. A search of PubMed with the search terms (trastuzumab deruxtecan) AND (interstitial lung disease) AND (guidelines) was conducted on November 1, 2021, with no restrictions based on publication date, and the two articles yielded by the search were included.

Treatment of MDA5-positive dermatomyositis complicated by gangrenous cholecystitis with tofacitinib.

BACKGROUND: Dermatomyositis is a rare idiopathic inflammatory disease with diverse presentations that can have varying degrees of cutaneous and systemic involvement. This phenotypic heterogeneity makes DM a therapeutic challenge. Some therapeutic drugs, such as hormones and immunosuppressants, have poor therapeutic effects. In recent years, tofacitinib has been reported to be effective in the treatment of dermatomyositis. CASE PRESENTATION: We report a case of anti-MDA5 antibody-positive dermatomyositis that was relieved after treatment with tofacitinib, during which gallbladder gangrene and suppurative cholecystitis occurred. After cholecystectomy, we continued to use tofacitinib and achieved a good therapeutic effect. CONCLUSIONS: Tofacitinib is effective in the treatment of anti-MDA5 antibody-positive dermatomyositis, but the risk of infection is increased. It can still be used after infection control. Close follow-up should be performed during the use of tofacitinib.

Outcome of COVID-19 in interstitial lung disease patients treated with anti-inflammatory drugs and antiviral drugs.

A recent study reported that patients with interstitial lung disease (ILD) are at increased risk of death from coronavirus disease 2019 (COVID-19). However, there are no studies on the outcome of COVID-19 patients with preexisting ILD treated with corticosteroids or antiviral drugs. We extracted 26 patients with preexisting ILD by medical records and HRCT pattern. Of 503 patients with COVID-19, we selected 52 patients as control matched for age and sex. Twenty out of the 26 ILD patients (76.9%) received corticosteroid therapy, and 23 patients (88.5%) also received antiviral treatment with remdesivir or favipiravir. Although no statistical difference was found, the proportion of severe patients in ILD group tended to be higher than in non-ILD group (23.1% vs. 42.3%; p = 0.114). Also, mortality rate in ILD group tended to be higher than in non-ILD patients (11.5% vs. 3.8%; p = 0.326). In univariate analysis to evaluate risk factors for severe condition, diagnosis of idiopathic pulmonary fibrosis, usual interstitial pneumonia pattern, and honeycomb lung were not risk factors of severe disease. Treatment with corticosteroids, antiviral drugs, and immunosuppressive agents may affect the outcome of COVID-19 patients with ILD.

Mesalazine induced interstitial pneumonitis in the COVID era.

Mesalazine is the most widely used aminosalicylate for induction and maintenance of remission in patients with mild-to-moderate ulcerative colitis (UC). Drug-induced hypersensitivity pneumonitis is considered very rare (<1/10.000 patients). Due to its rarity and the scarce cases reported, mesalazine-induced lung injury needs to be highly suspected in a patient with onset of respiratory symptoms and UC under treatment with salicylates. It should make the clinician formulate a differential diagnosis that includes not only infections (tuberculosis, bacterial...) or the inflammatory bowel disease itself, but also the current coronavirus disease 2019 (COVID-19) since their clinical and radiological manifestations may be very similar.

Post-COVID-19 interstitial lung disease presenting with profound hypoxemia: Report of three cases demonstrating a good response to high-dose corticosteroid therapy.

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which leads to critical pneumonia, although the clinical courses vary. In some cases, COVID-19 pneumonia causes secondary pulmonary fibrosis, which can retain radiological changes and prolong respiratory symptoms. Interstitial lung disease (ILD) secondary to COVID-19 is thought to be caused by multiple pathologies, such as excessive cytokines and abnormal repair processes elaborated by lung cells (epithelium, mesenchyme, and alveolar macrophages) after lung injury rather than viral invasion itself. Immunosuppression therapy may improve chronic respiratory symptoms and radiological changes in post-COVID-19 ILD, although the treatment is not yet established. Herein, we report three patients with post-COVID-19 ILD who presented with profound hypoxemia that had a good response to high-dose corticosteroid therapy. Further and larger studies are needed to establish post-COVID-19 ILD.

Could pulmonary low-dose radiation therapy be an alternative treatment for patients with COVID-19 pneumonia? Preliminary results of a multicenter SEOR-GICOR nonrandomized prospective trial (IPACOVID trial).

PURPOSE: To evaluate the efficacy and safety of lung low-dose radiation therapy (LD-RT) for pneumonia in patients with coronavirus disease 2019 (COVID-19). MATERIALS AND METHODS: Inclusion criteria comprised patients with COVID-19-related moderate-severe pneumonia warranting hospitalization with supplemental O2 and not candidates for admission to the intensive care unit because of comorbidities or general status. All patients received single lung dose of 0.5 Gy. Respiratory and systemic inflammatory parameters were evaluated before irradiation, at 24 h and 1 week after LD-RT. Primary endpoint was increased in the ratio of arterial oxygen partial pressure (PaO2) or the pulse oximetry saturation (SpO2) to fractional inspired oxygen (FiO2) ratio of at least 20% at 24 h with respect to the preirradiation value. RESULTS: Between June and November 2020, 36 patients with COVID-19 pneumonia and a mean age of 84 years were enrolled. Seventeen were women and 19 were men and all of them had comorbidities. All patients had bilateral pulmonary infiltrates on chest X­ray. All patients received dexamethasone treatment. Mean SpO2 pretreatment value was 94.28% and the SpO2/FiO2 ratio varied from 255 mm Hg to 283 mm Hg at 24 h and to 381 mm Hg at 1 week, respectively. In those who survived (23/36, 64%), a significant improvement was observed in the percentage of lung involvement in the CT scan at 1 week after LD-RT. No adverse effects related to radiation treatment have been reported. CONCLUSIONS: LD-RT appears to be a feasible and safe option in a population with COVID-19 bilateral interstitial pneumonia in the presence of significant comorbidities.

Role of JAK/STAT in Interstitial Lung Diseases; Molecular and Cellular Mechanisms.

Interstitial lung diseases (ILDs) comprise different fibrotic lung disorders characterized by cellular proliferation, interstitial inflammation, and fibrosis. The JAK/STAT molecular pathway is activated under the interaction of a broad number of profibrotic/pro-inflammatory cytokines, such as IL-6, IL-11, and IL-13, among others, which are increased in different ILDs. Similarly, several growth factors over-expressed in ILDs, such as platelet-derived growth factor (PDGF), transforming growth factor ß1 (TGF-ß1), and fibroblast growth factor (FGF) activate JAK/STAT by canonical or non-canonical pathways, which indicates a predominant role of JAK/STAT in ILDs. Between the different JAK/STAT isoforms, it appears that JAK2/STAT3 are predominant, initiating cellular changes observed in ILDs. This review analyzes the expression and distribution of different JAK/STAT isoforms in ILDs lung tissue and different cell types related to ILDs, such as lung fibroblasts and alveolar epithelial type II cells and analyzes JAK/STAT activation. The effect of JAK/STAT phosphorylation on cellular fibrotic processes, such as proliferation, senescence, autophagy, endoplasmic reticulum stress, or epithelial/fibroblast to mesenchymal transition will be described. The small molecules directed to inhibit JAK/STAT activation were assayed in vitro and in in vivo models of pulmonary fibrosis, and different JAK inhibitors are currently approved for myeloproliferative disorders. Recent evidence indicates that JAK inhibitors or monoclonal antibodies directed to block IL-6 are used as compassionate use to attenuate the excessive inflammation and lung fibrosis related to SARS-CoV-2 virus. These altogether indicate that JAK/STAT pathway is an attractive target to be proven in future clinical trials of lung fibrotic disorders.