Progressive Pulmonary Fibrosis: Where Are We Now? / 결핵및호흡기질환

Interstitial lung diseases (ILDs) are a diverse collection of lung disorders sharing similar features, such as inflammation and fibrosis. The diagnosis and management of ILD require a multidisciplinary approach using clinical, radiological, and pathological evaluation. Progressive pulmonary fibrosis (PPF) is a distinct form of progressive and fibrotic disease, occurring in ILD cases other than in idiopathic pulmonary fibrosis (IPF). It is defined based on clinical symptoms, lung function, and chest imaging, regardless of the underlying condition. The progression to PPF must be monitored through a combination of pulmonary function tests (forced vital capacity [FVC] and diffusing capacity of the lung for carbon monoxide), an assessment of symptoms, and computed tomography scans, with regular follow-up. Although the precise mechanisms of PPF remain unclear, there is evidence of shared pathogenetic mechanisms with IPF, contributing to similar disease behavior and worse prognosis compared to non-PPF ILD. Pharmacological treatment of PPF includes immunomodulatory agents to reduce inflammation and the use of antifibrotics to target progressive fibrosis. Nintedanib, a known antifibrotic agent, was found to be effective in slowing IPF progression and reducing the annual rate of decline in FVC among patients with PPF compared to placebos. Nonpharmacological treatment, including pulmonary rehabilitation, supplemental oxygen therapy, and vaccination, also play important roles in the management of PPF, leading to comprehensive care for patients with ILD. Although there is currently no cure for PPF, there are treatments that can help slow the progression of the disease and improve quality of life.

Diagnostic Approaches for Idiopathic Pulmonary Fibrosis / 결핵및호흡기질환

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrosing interstitial pneumonia with a very poor prognosis. Accurate diagnosis of IPF is essential for good outcomes but remains a major medical challenge due to variability in clinical presentation and the shortcomings of existing diagnostic tests. Medical history collection is the first and most important step in the IPF diagnosis process; the clinical probability of IPF is high if the suspected patient is 60 years or older, male, and has a history of cigarette smoking. Systemic assessment for connective tissue disease is essential in the initial evaluation of patients with suspected IPF to identify potential causes of interstitial lung disease (ILD). Radiologic examination using high-resolution computed tomography plays a pivotal role in the evaluation of patients with ILD, and prone and expiratory computed tomography images can be considered. If additional tests such as surgical lung biopsy or transbronchial lung cryobiopsy are needed, transbronchial lung cryobiopsy should be considered as an alternative to surgical lung biopsy in medical centers with experience performing this procedure. Diagnosis through multidisciplinary discussion (MDD) is strongly recommended as MDD has become the cornerstone for diagnosis of IPF, and the scope of MDD has expanded to monitoring of disease progression and suggestion of appropriate treatment options.

Lyophilized allogeneic costal cartilage graft for septorhinoplasty

Background@#As rhinoplasty techniques have become more complex, surgeons often need more than what septal or conchal cartilage can provide. While costal cartilage became more popular for that reason, some surgeons are still uncomfortable with its invasiveness and donor site morbidity. Here, we used lyophilized allogeneic costal cartilage for septorhinoplasty and investigated its safety and usefulness. @*Methods@#The costal cartilage was harvested from a cadaveric donor and treated via multiple steps, including defatting and lyophilization, to remove all viable cells and antigenicity. The cartilage was then stored at room temperature and rehydrated 24 hours before use. Lyophilized cartilage allografts were used in 20 patients. Three types of septal graft were performed — spreader, batten, and extension — to correct septal or columellar deviation and enhance the nasal tip. @*Results@#The mean follow-up period was 4.3 years. In all cases, the graft successfully met the rhinoplasty purpose. No significant deformation was detected in any of the patients. Although warping was observed in one patient (5%), there was no case of clinical infection, extrusion, or graft removal and no revisional surgery for an unfavorable aesthetic result. @*Conclusions@#Lyophilized allogeneic cartilage was used for septorhinoplasty very safely and effectively. It can be carved into any shape and has all other properties required for perfectly replacing autologous costal cartilage. The main advantage of cartilage allografts is a limitless supply of high-quality cartilage without donor site morbidity. The disadvantages include the need for special facilities and manpower and extra covering cost.

COVID-19 Vaccine-Associated Pneumonitis in the Republic of Korea:A Nationwide Multicenter Survey

Background@#Recent reports have suggested that pneumonitis is a rare complication following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).However, its clinical features and outcomes are not well known. The aim of this study was to identify the clinical characteristics and outcomes of patients with vaccine-associated pneumonitis following vaccination against SARS-CoV-2. @*Methods@#In this nationwide multicenter survey study, questionnaires were distributed to pulmonary physicians in referral hospitals. They were asked to report cases of development or exacerbation of interstitial lung disease (ILD) associated with the coronavirus disease 2019 vaccine. Vaccine-associated pneumonitis was defined as new pulmonary infiltrates documented on chest computed tomography within 4 weeks of vaccination and exclusion of other possible etiologies. @*Results@#From the survey, 49 cases of vaccine-associated pneumonitis were identified between February 27 and October 30, 2021. After multidisciplinary discussion, 46 cases were analyzed. The median age was 66 years and 28 (61%) were male. The median interval between vaccination and respiratory symptoms was 5 days. There were 20 (43%), 17 (37%), and nine (19%) patients with newly identified pneumonitis, exacerbation of pre-diagnosed ILD, and undetermined pre-existing ILD, respectively. The administered vaccines were BNT162b2 and ChAdOx1 nCov-19/AZD1222 each in 21 patients followed by mRNA-1273 in three, and Ad26.COV2.S in one patient. Except for five patients with mild disease, 41 (89%) patients were treated with corticosteroid. Significant improvement was observed in 26 (57%) patients including four patients who did not receive treatment. However, ILD aggravated in 9 (20%) patients despite treatment. Mortality was observed in eight (17%) patients. @*Conclusion@#These results suggest pneumonitis as a potentially significant safety concern for vaccines against SARS-CoV-2. Clinical awareness and patient education are necessary for early recognition and prompt management. Additional research is warranted to identify the epidemiology and characterize the pathophysiology of vaccine-associated pneumonitis.

The Value of 18 F-FDG PET/CT in Evaluating Disease Severity and Prognosis in Idiopathic Pulmonary Fibrosis Patients

Background@#Several parameters are useful for assessing disease severity in idiopathic pulmonary fibrosis (IPF); however, the role of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) is not well-defined. We aimed to evaluate the value of 18 F-FDG PET/CT for assessing disease severity and prognosis in IPF patients. @*Methods@#Clinical data of 89 IPF patients (mean age: 68.1 years, male: 94%) who underwent18 F-FDG PET/CT for evaluation of lung nodules or cancer staging were retrospectively reviewed. Mean and maximal standardized uptake values (SUV mean , SUV max , respectively) were measured in the fibrotic area. Adjusted SUV, including SUV ratio (SUVR, defined as SUV max -to-liver SUV mean ratio), tissue fraction-corrected SUV mean (SUV meanTF ), and SUVR (SUVRTF ), and tissue-to-blood ratio (SUV max /SUV mean venous; TBR blood ) were obtained. Death was defined as the primary outcome, and associations between other clinical parameters (lung function, exercise capacity, C-reactive protein [CRP] level) were also investigated. @*Results@#All SUV parameters were inversely correlated with the forced vital capacity, diffusing capacity for carbon monoxide, and positively correlated with CRP level and the gender-agephysiology index. The SUV mean , SUV max , and SUV meanTF were associated with changes in lung function at six months. The SUVR (hazard ratio [HR], 1.738; 95% confidence interval [CI], 1.011–2.991), SUVR TF (HR, 1.441; 95% CI, 1.000–2.098), and TBR blood (HR, 1.377; 95% CI, 1.038–1.827) were significant predictors for mortality in patients with IPF in the univariate analysis, but not in the multivariate analysis. @*Conclusion@#18 F-FDG PET/CT may provide additional information on the disease severity and prognosis in IPF patients, and the SUVR may be superior to other SUV parameters.

Pleuroparenchymal fibroelastosis in Korean patients: clinico-radiologic-pathologic features and 2-year follow-up

Background/Aims@#Pleuroparenchymal fibroelastosis (PPFE) is a type of rare idiopathic interstitial pneumonia that is characterized by predominantly upper lobe involvement with pleural fibrosis and subjacent parenchymal fibrosis. This study aimed to determine the clinico-radiologic-pathologic features and prognosis of Korean patients with PPFE. @*Methods@#A total of 26 patients who were confirmed to have PPFE by lung biopsy, were included, and their clinico-radiologic-pathologic findings were retrospectively analyzed. @*Results@#The mean follow-up period was 23.8 months, and the mean age of the patients was 62.5 years; 61.5% were men and 50% were smokers. Cough and dyspnea were the most frequent presenting symptoms, and restrictive pattern was the most common observation in lung function. In 84.6% of the subjects, lower lobe involvement was found on chest computed tomography, and the usual interstitial pneumonia (UIP) pattern was the most common (59.1%). Among patients whose lower lobe was biopsied (n = 13), the UIP pattern was the most common (46.2%). Patients with lower lobe involvement were older and walked a shorter distance during the 6-minute walk test, compared to those without. Spontaneous pneumothorax was a common complication (26.9%), and 15.4% of the patients died mostly due to pneumonia (100%). The 1- and 3-year survival rates were 90.2% and 84.5%, respectively. @*Conclusions@#Clinical features of Korean patients with PPFE were similar to those reported previously; however, lower lobe involvement was more frequent. During follow-up, one-fourth of the patients experienced pneumothorax and one-fifth died from pneumonia.

New Diagnostic Guidelines for Idiopathic Pulmonary Fibrosis / 대한내과학회지

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing interstitial lung disease characterized by worsening lung function and dyspnea. The prognosis of IPF patients is poor, as median survival is approximately 3 years. However, recently developed IPF-specific therapies have shown improved efficacies in terms of reducing lung function decline and mortality. Therefore, the early recognition and accurate diagnosis of IPF are crucial. In 2018, new guidelines for the diagnosis of IPF were published by the Fleischner Society and by the American Thoracic Society/European Respiratory Society/Japanese Respiratory Society/Latin American Thoracic Society (ATS/ERS/JRS/ALAT). Both guidelines emphasize the need for a thorough history taking and physical examination to exclude an alternative diagnosis, such as exposure-related or connective tissue disease. The most informative initial examination is high-resolution computed tomography, the results of which can indicate the need for bronchoalveolar lavage or surgical lung biopsy, based on a multidisciplinary discussion of the findings and the patient's clinical condition. A multidisciplinary discussion of the clinico-radiologic-pathologic findings is currently the gold standard in the diagnoisis of IPF and will allow the more effective and timely treatment of these patients.

New Diagnostic Guidelines for Idiopathic Pulmonary Fibrosis / 대한내과학회지

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing interstitial lung disease characterized by worsening lung function and dyspnea. The prognosis of IPF patients is poor, as median survival is approximately 3 years. However, recently developed IPF-specific therapies have shown improved efficacies in terms of reducing lung function decline and mortality. Therefore, the early recognition and accurate diagnosis of IPF are crucial. In 2018, new guidelines for the diagnosis of IPF were published by the Fleischner Society and by the American Thoracic Society/European Respiratory Society/Japanese Respiratory Society/Latin American Thoracic Society (ATS/ERS/JRS/ALAT). Both guidelines emphasize the need for a thorough history taking and physical examination to exclude an alternative diagnosis, such as exposure-related or connective tissue disease. The most informative initial examination is high-resolution computed tomography, the results of which can indicate the need for bronchoalveolar lavage or surgical lung biopsy, based on a multidisciplinary discussion of the findings and the patient's clinical condition. A multidisciplinary discussion of the clinico-radiologic-pathologic findings is currently the gold standard in the diagnoisis of IPF and will allow the more effective and timely treatment of these patients.

Birt-Hogg-Dubé syndrome in Korean: clinicoradiologic features and long term follow-up

BACKGROUND/AIMS@#Birt-Hogg-Dubé (BHD) syndrome is a rare autosomal dominant disorder that is characterized by skin fibrofolliculomas, pulmonary cysts, and renal tumors. The objective of this study was to describe the features of Korean patients with BHD syndrome.@*METHODS@#Clinical data were retrospectively reviewed in 12 patients (10 confirmed by direct sequencing of the folliculin (FLCN) gene and two confirmed by clinical diagnosis) diagnosed from 2004 to 2016 at Asan Medical Center, Seoul, South Korea. Criteria proposed by the European BHD consortium were used for diagnosis.@*RESULTS@#The median follow-up was 52 months. The mean age was 41.3 years and 66.7% were female. Eight patients (66.7%) had a history of pneumothorax, which was recurrent in 75%. Skin lesions were detected in 25.0% and renal cancer in 25.0%. Among mutations of the FLCN gene, the duplication of cytosine in the C8 tract of exon 11 (c.1285dupC) was the most common (40%); however, a novel heterozygous sequence variant of c.31T>C (p.C11R) in exon 4 was detected in one patient. All patients had multiple and bilateral pulmonary cysts, distributed in predominantly lower, peripheral and subpleural regions of the lungs. Most patients showed preserved lung function that remained unchanged during follow-up, and two (16.7%) developed cancers (renal cancer in one and breast cancer in one).@*CONCLUSIONS@#Our data suggest that Korean patients with BHD syndrome may have a higher risk of pneumothorax, less frequent skin lesions, and a novel FLCN mutation compared to previous reports. Multiple bilateral and basal-predominant cysts were the most common radiologic features.

Korean Guidelines for Diagnosis and Management of Interstitial Lung Diseases: Part 2. Idiopathic Pulmonary Fibrosis / 결핵및호흡기질환

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrosing interstitial pneumonia, which presents with a progressive worsening dyspnea, and thus a poor outcome. The members of the Korean Academy of Tuberculosis and Respiratory Diseases as well as the participating members of the Korea Interstitial Lung Disease Study Group drafted this clinical practice guideline for IPF management. This guideline includes a wide range of topics, including the epidemiology, pathogenesis, risk factors, clinical features, diagnosis, treatment, prognosis, and acute exacerbation of IPF in Korea. Additionally, we suggested the PICO for the use of pirfenidone and nintendanib and for lung transplantation for the treatment of patients with IPF through a systemic literature review using experts' help in conducting a meta-analysis. We recommend this guideline to physicians, other health care professionals, and government personnel in Korea, to facilitate the treatment of patients with IPF.

Korean Guidelines for Diagnosis and Management of Interstitial Lung Diseases: Part 2. Idiopathic Pulmonary Fibrosis / 결핵

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrosing interstitial pneumonia, which presents with a progressive worsening dyspnea, and thus a poor outcome. The members of the Korean Academy of Tuberculosis and Respiratory Diseases as well as the participating members of the Korea Interstitial Lung Disease Study Group drafted this clinical practice guideline for IPF management. This guideline includes a wide range of topics, including the epidemiology, pathogenesis, risk factors, clinical features, diagnosis, treatment, prognosis, and acute exacerbation of IPF in Korea. Additionally, we suggested the PICO for the use of pirfenidone and nintendanib and for lung transplantation for the treatment of patients with IPF through a systemic literature review using experts' help in conducting a meta-analysis. We recommend this guideline to physicians, other health care professionals, and government personnel in Korea, to facilitate the treatment of patients with IPF.

Individualized Considerations Regarding Sub-Superficial Musculoaponeurotic System Facelift Techniques

Based on a thorough understanding of facial structure around the superficial musculoaponeurotic system (SMAS), some types of sub-SMAS techniques have emerged to allow more harmonious rejuvenation procedures in the lower face and midface. These techniques are the Hamra composite facelift, the Stuzin extended SMAS technique, the Barton high SMAS technique, and the Ramirez subperiosteal facelift, each of which involves a specific dissection plane and is informed by distinct rationales with reasonable support. Each patient presents a unique facial structure and undergoes an individual rate of aging. The facial structures of East Asian faces, in particular, differ from those of Western faces. While emphasizing that the theory of structural mid-cheek anatomy is an essential part of facial rejuvenation, we would like to discuss the advantages and disadvantages of various sub-SMAS facelift techniques and to propose the most suitable techniques for a variety of individual faces.

Various Applications of Deep Temporal Fascia in Rhinoplasty

PURPOSE: In Asians, nasal dorsal and tip augmentation procedures are usually performed at the same time, and most dorsal augmentations use implants. In this study, dorsal augmentation was given by various types of grafts using deep temporal fascia (DTF) for primary rhinoplasty cases using only autologous tissues to improve the curve of hump noses and depressions. For secondary rhinoplasty cases, DTF was used to improve implant demarcation and transparency. Such effectiveness and utility of DTF is discussed. MATERIALS AND METHODS: Between May 2009 and May 2012, we performed rhinoplasty using DTF in 175 patients, which included 78 secondary surgery patients and 128 female patients. The mean age of the patients was 31.4. DTF was utilized with various types of grafts without implants to improve the curve in dorsal augmentation of hump noses and cases that required curve betterment. DTF was used to improve implant demarcation and transparency for secondary cases. RESULTS: The mean follow-up duration was 1.5 years. Of the 175 patients, 81% were satisfied with the natural correction achieved, whereas 19% complained of undercorrection, which was resolved with additional surgery. No specific complications such as nasal inflammation or contractures were observed. CONCLUSION: DTF can be used with various graft methods for correction of radix, dorsal, and tip irregularities. It can also be used to correct implant contour transparency in secondary rhinoplasty and thus may be considered as a useful supplementary graft material in rhinoplasty for Asians.

A Case of IgG4-Related Lung Disease Mimicking Non-Specific Interstitial Pneumonia / 대한내과학회지

Immunoglobulin (Ig) G4-related disease is a recently described systemic inflammatory disease characterized by high serum IgG4 concentrations and sclerosing inflammation of numerous IgG4-positive plasma cells that responds favorably to steroid treatment. Although initial description of this disorder focused on its pancreatic presentation, it has become apparent that it is a systemic disease. In this report, we describe a case of IgG4-related lung disease presenting as non-specific interstitial pneumonia in a 78-year-old male with interstitial lung disease. Pathological examination through video-assisted thoracic surgery showed a non-specific interstitial pneumonia pattern and numerous (> 50/high-power field) infiltrating IgG4-positive plasma cells. Laboratory tests also revealed a high serum IgG4 concentration. Prednisolone therapy was initiated and his symptoms and reticular opacity improved after two months of treatment.

A Case of Acute Lung Injury due to Mercury Vapor Inhalation / 대한내과학회지

Mercury is traditionally used as a dye for making amulets in Korea. Inhaling the vapor produced by burning mercury damages major organs, such as the lungs, kidneys, and brain. We herein present a case of a 41-year-old man who complained of abdominal pain and dyspnea. A chest X-ray and computed tomography scan showed infiltration in both upper lung lobes. A thorough medical history revealed that the patient had made amulets prior to developing symptoms, and blood and urine tests confirmed elevated levels of mercury. Dimercaptosuccinic acid was used to chelate the mercury, and methylprednisolone was used to treat the acute lung injury. No kidney or nervous system complications were detected during follow-up. Inhalation of mercury vapor should be suspected in patients with acute lung injury involving both upper lobes.

10th Rib Cartilage: Another Option of the Costal Cartilage Graft for Rhinoplasty

BACKGROUND: The costal cartilage allows for versatile and stable cartilage supply for rhi-noplasty but disadvantages remain; to minimize these, the 10th costal cartilage was used. We present our experience with the use of the 10th costal cartilage as autologous graft material for rhinoplasty. METHODS: Sixty-four patients whose 10th costal cartilage had been used for correction of severe caudal nasal deviation, secondary cleft lip nasal deformity, and secondary rhi-noplasty with difficulty using the septal and auricular cartilages were enrolled in this study from November 2008 to December 2012. To evaluate the efficacy and safety of this method in rhinoplasty, donor-site morbidity, scarring, and postoperative results, including availability of graft material and complications, were assessed. RESULTS: The mean time for cartilage harvesting was 18 minutes, and the mean length of the harvested cartilage was 2.4 cm. The harvested cartilage was used for columellar struts and tip onlay grafts. The natural curvature of the 10th costal cartilage was used, depending on the purpose of the strut. It could be applied without carving in 38 cases (59%). Although revision was performed in three patients, there were no graft-related complications. CONCLUSIONS: The 10th costal cartilage can be harvested safely and quickly, and its han-dling procedure is simple. As such, it is a good option as an autologous graft for rhinoplasty.

Guideline for the prevention and management of particulate matter/Asian dust particle-induced adverse health effect on the patients with pulmonary diseases

The aim of this study was to develop guidelines for the prevention and management of particulate matter (PM)/Asian dust particle (ADP)-induced adverse effects in patients with pulmonary diseases. The guideline development committee reviewed the literature on particulate matter, ADP, and pulmonary diseases. In adults, exposure to particulate matter with a diameter of 10 microm or less (PM10) induces a decline in lung function. PM exposure confers an increased risk of lung cancer, and PM10 is associated with increased hospital admission and mortality due to chronic obstructive pulmonary disease. ADP exposure is associated with increased hospital admission and emergency room visits due to chronic obstractive pulmonary disease exacerbation. Idiopathic pulmonary fibrosis exacerbation may also be induced by pollution, although the evidence for this is very weak. There is no published study on the proper prevention or management of the exacerbation of pulmonary diseases due to PM or ADP exposure. The preventive use of a facial mask with a filter in patients with pulmonary disease should be considered carefully because there have been no clinical study of the efficacy and adverse effects of masks in pulmonary diseases. The committee created guidelines based on a discussion of the peer-reviewed literature. The proper management of PM- and ADP-induced exacerbation of pulmonary disease and the efficacy of facial mask use should be evaluated in future studies.

Interstitial Lung Disease in Connective Tissue Disease

Interstitial lung disease (ILD) is one of the most serious pulmonary complications of connective tissue diseases (CTDs), resulting in significant morbidity and mortality. ILD is frequently seen in CTDs, particularly systemic sclerosis, polymyositis/dermatomyositis, and rheumatoid arthritis; however, determining that ILD is associated with an established CTD requires the exclusion of alternative causes. Non-specific interstitial pneumonia is the most commonly observed histopathological pattern in CTD-associated ILD (CTD-ILD) except for rheumatoid arthritis, characterized by a higher frequency of usual interstitial pneumonia. Although CTD-ILD usually shows a stable or slowly progressive course, a subgroup exhibits a more severe and progressive course and requires pharmacologic intervention. Treatment strategies typically involve empirical use of immunosuppressive therapies, although a large, randomized study has examined the impact of immunosuppressive therapy for systemic sclerosis associated ILD and should also address comorbid conditions considering implementation of adjunctive therapeutic strategies. A subgroup of patients with idiopathic interstitial pneumonia who meet some, but not all, diagnostic criteria for CTDs were identified and well organized prospective studies are needed in to better determine whether evidence of autoimmunity in those plays a part in the evolution to well-defined CTDs or carries prognostic significance.

Two Cases of Birt-Hogg-Dube Syndrome with Pulmonary Cysts / 대한내과학회지

Birt-Hogg-Dube (BHD) syndrome is a rare autosomal-dominant disease caused by germline folliculin (FLCN) mutations, characterized by fibrofolliculoma or trichodiscoma, renal tumors, and multiple lung cysts with or without spontaneous pneumothorax. Here, we report two cases of BHD syndrome that presented with bilateral pulmonary cysts. One patient was a 39-year-old woman who had a history of pneumothorax, multiple papules on her cheeks, and a family history of the same skin lesions and renal cell carcinoma in her father. BHD syndrome was confirmed by molecular tests that revealed a missense mutation in FLCN gene (exon 4, c.31T > C). The other patient was a 56-year-old man who showed FCLN gene polymorphism and typical radiopathological features of multiple cysts in the lung, but apparently no other manifestation.

A Case of IgG4-Related Lung Disease Presenting as Interstitial Lung Disease / 결핵및호흡기질환

Intrathoracic involvement of immunoglobulin G4 (IgG4)-related disease has recently been reported. However, a subset of the disease presenting as interstitial lung disease is rare. Here, we report a case of a 35-year-old man with IgG4-related lung disease with manifestations similar to those of interstitial lung disease. Chest computed tomography showed diffuse ground glass opacities and rapidly progressive pleural and subpleural fibrosis in both upper lobes. Histological findings showed diffuse interstitial lymphoplasmacytic infiltration with an increased number of IgG4-positive plasma cells. Serum levels of IgG and IgG4 were also increased. The patient was diagnosed with IgG4-related lung disease, treated with anti-inflammatory agents, and showed improvement. Lung involvement of IgG4-related disease can present as interstitial lung disease and, therefore, should be differentiated when evaluating interstitial lung disease.