Development and external validation of the DOAT and DOATS scores: simple decision support tools to identify disease progression among nonelderly patients with mild/moderate COVID-19.

BACKGROUND: During the fifth wave of the coronavirus disease 2019 (COVID-19) pandemic in Japan, which took place between June and September 2021, a significant number of COVID-19 cases with deterioration occurred in unvaccinated individuals < 65 years old. However, the risk factors for COVID-19 deterioration in this specific population have not yet been determined. This study developed a prediction method to identify COVID-19 patients < 65 years old who are at a high risk of deterioration. METHODS: This retrospective study analyzed data from 1,675 patients < 65 years old who were admitted to acute care institutions in Fukushima with mild-to-moderate-1 COVID-19 based on the Japanese disease severity criteria prior to the fifth wave. For validation, 324 similar patients were enrolled from 3 hospitals in Yamagata. Logistic regression analyses using cluster-robust variance estimation were used to determine predictors of disease deterioration, followed by creation of risk prediction scores. Disease deterioration was defined as the initiation of medication for COVID-19, oxygen inhalation, or mechanical ventilation starting one day or later after admission. RESULTS: The patients whose condition deteriorated (8.6%) tended to be older, male, have histories of smoking, and have high body temperatures, low oxygen saturation values, and comorbidities, such as diabetes/obesity and hypertension. Stepwise variable selection using logistic regression to predict COVID-19 deterioration retained comorbidities of diabetes/obesity (DO), age (A), body temperature (T), and oxygen saturation (S). Two predictive scores were created based on the optimism-corrected regression coefficients: the DOATS score, including all of the above risk factors, and the DOAT score, which was the DOATS score without oxygen saturation. In the original cohort, the areas under the receiver operating characteristic curve (AUROCs) of the DOATS and DOAT scores were 0.81 (95% confidence interval [CI] 0.77-0.85) and 0.80 (95% CI 0.76-0.84), respectively. In the validation cohort, the AUROCs for each score were both 0.76 (95% CI 0.69-0.83), and the calibration slopes were both 0.80. A decision curve analysis confirmed the clinical practicability of both scores in the validation cohort. CONCLUSIONS: We established two prediction scores that can quickly evaluate the risk of COVID-19 deterioration in mild/moderate patients < 65 years old.

Real-world clinical outcomes of treatment with casirivimab-imdevimab among patients with mild-to-moderate coronavirus disease 2019 during the Delta variant pandemic.

Background: Mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may reduce the efficacy of neutralizing monoclonal antibody therapy against coronavirus disease 2019 (COVID-19). We here evaluated the efficacy of casirivimab-imdevimab in patients with mild-to-moderate COVID-19 during the Delta variant surge in Fukushima Prefecture, Japan. Methods: We enrolled 949 patients with mild-to-moderate COVID-19 who were admitted to hospital between July 24, 2021 and September 30, 2021. Clinical deterioration after admission was compared between casirivimab-imdevimab users (n = 314) and non-users (n = 635). Results: The casirivimab-imdevimab users were older (P < 0.0001), had higher body temperature (≥ 38°C) (P < 0.0001) and greater rates of history of cigarette smoking (P = 0.0068), hypertension (P = 0.0004), obesity (P < 0.0001), and dyslipidemia (P < 0.0001) than the non-users. Multivariate logistic regression analysis demonstrated that receiving casirivimab-imdevimab was an independent factor for preventing deterioration (odds ratio 0.448; 95% confidence interval 0.263-0.763; P = 0.0023). Furthermore, in 222 patients who were selected from each group after matching on the propensity score, deterioration was significantly lower among those receiving casirivimab-imdevimab compared to those not receiving casirivimab-imdevimab (7.66% vs 14.0%; p = 0.021). Conclusion: This real-world study demonstrates that casirivimab-imdevimab contributes to the prevention of deterioration in COVID-19 patients after hospitalization during a Delta variant surge.

Efficacy of early antifibrotic treatment for idiopathic pulmonary fibrosis.

BACKGROUND: Although antifibrotic drugs, including nintedanib and pirfenidone, slow the progression of idiopathic pulmonary fibrosis (IPF), there is little data about the timing of start of antifibrotic treatment in real-world clinical practice. The present study aimed to clarify the efficacy of nintedanib and pirfenidone in patients with early-stage IPF. METHODS: We compared survival and disease progression between patients with IPF with Japanese Respiratory Society (JRS) disease severity system stage I with and without oxygen desaturation on the 6-min walk test (6MWT) and increased the gender-age-physiology (GAP) staging. We examined the efficacy of antifibrotic drugs in patients with early-stage IPF. RESULTS: The severity of stage I IPF (n = 179) according to the JRS criteria consisted of the following GAP staging criteria: stage I, 111 cases; stage II, 58 cases; stage III, 10 cases. The duration from the initial visit to disease progression and survival time was significantly shorter in JRS stage I patients with oxygen desaturation on the 6MWT or with increased GAP staging (unfavorable group) compared with patients without those factors. In the unfavorable group, the relative decline in percentage predicted forced vital capacity (%FVC) over 6 months was significantly lower in patients undergoing antifibrotic treatment compared with non-treated patients. CONCLUSION: Antifibrotic drugs have a beneficial effect on the decline in %FVC in Japanese patients with early-stage IPF who have oxygen desaturation on the 6MWT or increased GAP staging.

The Utility of Virtual Bronchoscopy Using a Computed Tomography Workstation for Conducting Conventional Bronchoscopy: A Retrospective Analysis of Clinical Practice.

BACKGROUND: Recent clinical trials demonstrated the benefits of several guided-bronchoscopy technologies for the diagnosis of peripheral pulmonary lesions (PPLs). However, introduction of these technologies is expensive. Therefore, in clinical practice, these are unavailable in many hospitals. In contrast, virtual bronchoscopy (VB) using the computed tomography (CT) workstation can be made available immediately without additional cost as many hospitals already have the CT scan facility. However, the effectiveness of VB alone remains to be shown. OBJECTIVES: The aim of this study was to investigate the effect of VB using the CT workstation in hospitals performing conventional bronchoscopy. METHODS: Results from consecutive patients who underwent bronchoscopy for small PPLs (major diameter ≤30 mm) were retrospectively reviewed. Sixty-nine patients who underwent bronchoscopy without VB from April 2014 to March 2015 and 56 patients who underwent bronchoscopy with VB from April 2015 to December 2015 were assigned to non-VB and VB groups, respectively. We compared the two groups and analyzed the factors affecting the diagnostic yield. RESULTS: The VB group had a significantly higher diagnostic yield than the non-VB group (57.1 vs. 33.3%; p = 0.008). In the multivariate analysis, VB was identified as a significant factor affecting the diagnostic yield (odds ratio: 3.30, p = 0.011). CONCLUSIONS: In the conventional bronchoscopy settings, VB using the CT workstation is efficient for the diagnosis of PPLs when other guided-bronchoscopy techniques are unavailable.

Effectiveness of combined therapy with pirfenidone and inhaled N-acetylcysteine for advanced idiopathic pulmonary fibrosis: a case-control study.

BACKGROUND AND OBJECTIVE: Treatment with pirfenidone may slow the decline in vital capacity and increase progression-free survival (PFS) in idiopathic pulmonary fibrosis (IPF). The effects of combination therapy with inhaled N-acetylcysteine (NAC) and pirfenidone are unclear. We assessed the effects of this combination therapy in patients with advanced IPF. METHODS: Patients with a diagnosis of advanced IPF (Japanese Respiratory Society stage III/IV IPF) and a relative decline in forced vital capacity (FVC) of ≥ 10% within the previous 6 (± 2) months were enrolled. Outcomes were evaluated in a 12-month follow-up pulmonary function test. Treatment was considered ineffective if the decline in FVC was ≥ 10% and effective if the decline was <10%. We compared clinical characteristics, effectiveness and PFS between patients receiving inhaled NAC plus pirfenidone (n = 24) and those receiving pirfenidone alone (control; n = 10). RESULTS: Data from 34 IPF patients (age range, 59-82 years) were analysed. At the 12-month follow-up examination, treatment was deemed effective in 8 of 17 (47%) patients receiving NAC plus pirfenidone and in 2 of 10 (20%) receiving pirfenidone alone. The annual rate of change in FVC was -610 mL in the NAC plus pirfenidone group and -1320 mL in the pirfenidone group (P < 0.01). PFS was longer (304 days) in the NAC plus pirfenidone group than in the pirfenidone group (168 days; P = 0.016). CONCLUSIONS: Combination treatment with inhaled NAC and oral pirfenidone reduced the rate of annual FVC decline and improved PFS in patients with advanced IPF.

Recombinant human soluble thrombomodulin treatment for acute exacerbation of idiopathic pulmonary fibrosis: a retrospective study.

BACKGROUND: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) can be fatal, and abnormalities in the coagulation system of patients with AE-IPF have been reported. Recombinant human soluble thrombomodulin (rhTM) forms a complex with thrombin to inactivate coagulation. It also inhibits high-mobility group box protein 1 (HMGB-1), which results in the suppression of inflammation. OBJECTIVES: We aimed to evaluate the effectiveness of rhTM for the treatment of AE-IPF. METHODS: We retrospectively reviewed the medical records of 41 patients with AE-IPF who were admitted to our institution during the period 2006-2013. The clinical features and outcomes of 16 patients treated with rhTM (rhTM group) were compared with those of 25 patients treated with conventional therapy (control group). Patients were treated with corticosteroid (CS) pulse therapy for 3 days, followed by maintenance treatment with a tapered dose of CS. Patients in the rhTM group also received rhTM (0.06 mg/kg/day) for 6 days as an initial treatment, in combination with CS. RESULTS: Except for D-dimer level, there were no significant differences in the baseline characteristics of the 2 groups. When compared with the control group, the rhTM group had a significantly higher survival rate at 3 months (40 vs. 69%, p = 0.048). A univariate Cox proportional hazards regression model showed that the predictive factors for survival were lactate dehydrogenase level and rhTM treatment. Regarding adverse events, 1 patient in the rhTM group developed mild bleeding events. CONCLUSION: rhTM as an add-on to conventional treatment may improve survival in patients with AE-IPF.

Comparison of clinical characteristics and prognostic factors of combined pulmonary fibrosis and emphysema versus idiopathic pulmonary fibrosis alone.

BACKGROUND AND OBJECTIVE: The results of studies examining the outcome and the factors predicting prognosis in combined pulmonary fibrosis and emphysema (CPFE) have so far been contradictory. Our objective was to determine prognosis and the prognostic factors for CPFE. METHODS: Of 108 consecutive idiopathic pulmonary fibrosis (IPF) patients admitted to our hospital, 46 were diagnosed as having CPFE and 62 patients diagnosed as having IPF alone. We retrospectively compared the clinical features between these two groups. RESULTS: Annual increase in estimated systolic pulmonary arterial pressure (esPAP) was significantly greater in CPFE patients, and survival time was significantly lower. Moreover, the prognosis was unfavourable regardless of the presence of lung cancer. The multivariate Cox proportional hazard regression model showed that predictive factors were an increase in the modified Medical Research Council dyspnoea score and esPAP ≥ 30.4 mm Hg. We classified patients into the following four groups: CPFE with high esPAP (esPAP ≥ 30.4 mm Hg), CPFE with normal esPAP (esPAP < 30.4 mm Hg), IPF alone with high esPAP and IPF alone with normal esPAP. Survival in the CPFE with high esPAP group was significantly worse than that in the other three subgroups. Furthermore, CPFE with the paraseptal type of emphysema and high esPAP had the worst prognosis. CONCLUSIONS: This study demonstrated that the prognosis of CPFE is significantly worse than that of IPF alone. In particular, CPFE with paraseptal emphysema associated with high esPAP has an extremely poor prognosis.

Tolerability and efficacy of switching anti-fibrotic treatment from nintedanib to pirfenidone for idiopathic pulmonary fibrosis.

BACKGROUND: In real-world studies, the rate of discontinuation of nintedanib (NT) varies from 4% to 53%. Switching anti-fibrotic treatment in patients with idiopathic pulmonary fibrosis (IPF) has not been adequately investigated, and data on the tolerability and efficacy of changes in anti-fibrotic treatment is limited in clinical practice. OBJECTIVE: To identify factors associated with poor continuation of NT, efficacy and predictors of deterioration after switching from NT to pirfenidone (PFD) in patients with IPF. SUBJECTS AND METHODS: One hundred and seventy patients with IPF in whom NT was introduced between April 2017 and March 2022 were included to investigate NT continuation status and the effect of switching to PFD. RESULTS: A total of 123 patients (72.4%) continued NT for 1 year and had a significantly higher %forced vital capacity (FVC) at NT introduction than those who discontinued within 1 year (80.9% ± 16.3% vs. 71.9% ± 22.1%, P = 0.004). The determinant of poor NT continuation was the high GAP stage. On the other hand, 28 of 36 patients who discontinued NT because of disease progression switched to PFD. Consequently, FVC decline was suppressed before and after the change. The predictor of deterioration after the switch was a lower body mass index. CONCLUSIONS: In patients with IPF, early NT introduction increased continuation rates, and switching to PFD was effective when patients deteriorated despite initial NT treatment.

Immune checkpoint inhibitors in patients with lung cancer having chronic interstitial pneumonia.

Background: In interstitial pneumonia (IP)-associated lung cancer, immune checkpoint inhibitor pneumonitis (ICIP) is common with immune checkpoint inhibitor (ICI) treatment. The purpose of the present study was to clarify the safety and efficacy of ICI treatment for patients with lung cancer with IP. Methods: This multicentre retrospective observational study was conducted from June 2016 to December 2020 in patients with primary lung cancer with IP who received ICI treatment. Results: A total of 200 patients (median age 70 years; male/female, 176/24) were enrolled from 27 institutions. ICIP occurred in 61 patients (30.5%), pneumonitis grades 3-5 in 32 patients (15.5%) and death in nine patients (4.5%). The common computed tomography pattern of ICIP was organising pneumonia in 29 patients (47.5%). Subsequently, diffuse alveolar damage (DAD) pattern was observed in 19 patients (31.1%) who had a significantly worse prognosis than those with a non-DAD pattern (median progression-free survival (PFS) 115 days versus 226 days, p=0.042; median overall survival (OS) 334 days versus 1316 days, p<0.001). Immune-related adverse events (irAEs) occurred in approximately 50% of patients. Patients with irAEs (n=100) had a better prognosis than those without irAEs (n=100) (median PFS 200 days versus 77 days, p<0.001; median OS 597 days versus 390 days p=0.0074). The objective response rate and disease control rate were 41.3% and 68.5%, respectively. Conclusions: Although ICI treatment was effective for patients with lung cancer with IP, ICIP developed in approximately 30% of patients. Patients with irAEs had a significantly better PFS and OS than those without irAEs.

Immunoglobulin G4-related lung disease: clinicoradiological and pathological features.

BACKGROUND AND OBJECTIVE: Immunoglobulin G4 (IgG4)-related disease is a multi-organ disorder that can include the lungs. IgG4-related lung disease can present in various forms; the clinical, radiological and pathological features of patients with this disease have been assessed. METHODS: Forty-eight patients suspected of having IgG4-related lung disease, with a high serum concentration of IgG4 and abundant IgG4-positive plasma cell infiltration into the intrathoracic organs, were retrospectively evaluated. Their clinical features, chest imaging findings and pathological findings were examined, with final diagnoses made by an open panel conference. RESULTS: Of the 48 patients, 18 with extrathoracic manifestations were diagnosed as having IgG4-related lung disease. Most of these patients were middle-aged to elderly men. IgG4-related lung disease was characterized by high serum concentrations of IgG and IgG4, normal white blood cell count and serum C-reactive protein concentration and a good response to corticosteroids. Common radiological findings included mediastinal lymphadenopathy and thickening of the perilymphatic interstitium, with or without subpleural and/or peribronchovascular consolidation. Pathological examination showed massive lymphoplasmacytic infiltration with fibrosis in and around the lymphatic routes, with distribution well correlated with radiological manifestations. CONCLUSIONS: The findings suggest that the intrathoracic manifestations of IgG4-related lung disease develop through lymphatic routes of the lungs and show various clinical characteristics. Because some lymphoproliferative disorders show similar findings, the correlation of clinicoradiological and pathological characteristics is crucial for the diagnosis of IgG4-related lung disease.

Pleuroparenchymal fibroelastosis in mycobacterium avium complex lung disease.

We report a rare case of pleuroparenchymal fibroelastosis (PPFE) with interstitial lung disease progressed after an onset of mycobacterium avium complex (MAC) lung disease. Clinicians should pay attention to the management for patients with PPFE in MAC lung disease.

Successful baricitinib treatment of refractory anti-synthetase syndrome associated with interstitial lung disease.

A 47-year-old Japanese man was admitted with dyspnoea on exertion (DOE), skin rash and myalgia. Clinical findings of Gottron's sign and mechanic's hands were observed, with increased serum levels of Krebs von den Lungen-6, surfactant protein-D, creatine kinase, and anti-EJ on laboratory tests. In both lungs, chest computed tomography revealed diffuse reticular opacities and lower lobe predominance. The patient was diagnosed with anti-synthetase syndrome (ASS) and associated interstitial lung disease. Despite repeated administration of high-dose intravenous corticosteroids, cyclophosphamide and immunoglobulin, his skin rash, myalgia, and DOE followed a relapsing and remitting course. He was then given rituximab therapy. This was initially successful, but disease activity increased approximately 12 months after starting rituximab therapy. Finally, in addition to prednisolone and cyclosporine A, we administered baricitinib. There has been no relapse of the disease in the 12 months since he began baricitinib treatment.

Real-world clinical outcomes of treatment with molnupiravir for patients with mild-to-moderate coronavirus disease 2019 during the Omicron variant pandemic.

It is unclear whether molnupiravir has a beneficial effect on vaccinated patients infected with the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We here evaluated the efficacy of molnupiravir in patients with mild-to-moderate coronavirus disease 2019 (COVID-19) during the Omicron variant surge in Fukushima Prefecture, Japan. We enrolled patients with mild-to-moderate COVID-19 who were admitted to hospitals between January and April, 2022. Clinical deterioration after admission was compared between molnupiravir users (n = 230) and non-users (n = 690) after 1:3 propensity score matching. Additionally, we performed forward stepwise multivariate logistic regression analysis to evaluate the association between clinical deterioration after admission and molnupiravir treatment in the 1:3 propensity score-matched subjects. The characteristics of participants in both groups were balanced as indicated by covariates with a standardized mean difference of < 0.1. Regarding comorbidities, there was no imbalance between the two groups, except for the presence of hypertension, dyslipidemia, diabetes mellitus, and cardiac disease. The clinical deterioration rate was significantly lower in the molnupiravir users compared to the non-users (3.90% vs 8.40%; P = 0.034). Multivariate logistic regression analysis demonstrated that receiving molnupiravir was a factor for preventing deterioration (odds ratio 0.448; 95% confidence interval 0.206-0.973; P = 0.042), independent of other covariates. This real-world study demonstrates that molnupiravir contributes to the prevention of deterioration in COVID-19 patients after hospitalization during the Omicron variant phase.

Coronavirus disease 2019 vaccination-induced acute exacerbation in idiopathic pulmonary fibrosis.

We report a rare case of acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) after coronavirus disease 2019 (COVID-19) vaccination. Clinicians should be aware of this COVID-19 vaccination-induced AE in IPF.

Multiple endotracheal metastases of combined small cell lung carcinoma.

We report a very rare case of combined small cell lung carcinoma (C-SCLC) which presented as persistent cough and was due to endotracheal metastases. Clinicians should be aware of this unusual site of metastases from a C-SCLC.

Immunoglobulin G4-positive interstitial pneumonia associated with pleuroparenchymal fibroelastosis.

A 79-year-old former smoking Japanese man was admitted to our hospital with a 2-year history of dry cough and dyspnoea on exertion. High-resolution computed tomography of the chest revealed reticulation and perilobular opacity with bronchial wall thickening and ground-glass opacities (GGOs) in both lungs, in addition to subpleural dense consolidation (pleuroparenchymal fibroelastosis-like lesion; PPFE-like lesion) predominantly in the bilateral upper lobes. Serum immunoglobulin G4 (IgG4) was elevated (348 mg/dl). Lung biopsy specimens obtained by video-assisted surgery revealed a mixture of usual interstitial pneumonia (IP) and non-specific IP pattern admixed with PPFE. In addition, immunohistochemical staining of IgG4 showed numerous IgG4-positive plasma cells. Consequently, he was diagnosed with IgG4-positive IP associated with PPFE. We initiated a combination therapy with prednisolone and cyclosporine as a calcineurin inhibitor. During prednisolone tapering, his clinical conditions and GGOs improved gradually over 12 months. However, reticular opacities and PPFE-like lesions remained unchanged, and pulmonary function test findings slightly deteriorated.

Surgical lung biopsy for interstitial lung diseases-a single center study of 129 patients.

Background: According to guidelines for the diagnosis and treatment of interstitial lung diseases (ILDs), a diagnostic surgical lung biopsy should be used to obtain the differential diagnosis of an ILD in patients with ILDs, which are difficult to distinguish clinically. However, the risk of developing postoperative complications such as postoperative pulmonary fistula or acute exacerbation is a concern. The purpose of this study was to evaluate the safety of surgical lung biopsy for the differential diagnosis of ILDs. Methods: From October 2007 to July 2019, 129 patients thought to have ILD underwent a surgical lung biopsy at Toho University Omori Medical Center. We conducted a retrospective study on the diagnosis and safety of surgical lung biopsy for patients with ILD. Results: The 30- and 60-day mortality was 0%. Postoperative complications occurred in 13 of 129 (10.1%) patients. The complications included pneumothorax in 8 (6.2%) patients after removal of the chest tube, postoperative pneumonia in 2 (1.0%), and acute exacerbation in 1 (0.8%). Postoperative pneumothorax was observed in 4 of 13 patients (30.7%) who underwent a biopsy of the apex of the lung (right S1, left S1+2), which was a significantly higher rate of postoperative pneumothorax than seen for patients undergoing biopsy at other sites (P=0.0086). Conclusions: Surgical lung biopsy for the differential diagnosis of an ILD was performed safely. However, biopsy sites for ILDs need to be carefully selected to avoid postoperative complications.

Histopathological bronchial reconstruction of human bronchiolitis obliterans.

To clarify the morphological mechanisms of airway obliteration in bronchiolitis obliterans (BO) associated with various causes, we conducted a retrospective study of 9 patients with a histological diagnosis of BO. The morphological characteristics were analyzed by histopathological bronchial reconstruction. BO was classified into two major morphologic subtypes: constrictive BO (CoB) and cellular/destructive BO (CDB). CoB is characterized by concentric narrowing of the airway lumen due to submucosal fibrosis. In contrast, in CDB the narrowing of the airway lumen is due to intraluminal, mural, and peribronchiolar infiltration of inflammatory cells as well as proliferation of granulation tissue. The histopathological diagnosis was CoB in 6 patients and CDB in 3 patients. Macroscopic bronchial reconstruction in CoB demonstrated that the beginnings of bronchial obliterations were in the 4th to 7th branches, numbering from each segmental bronchus and the lesions were distributed intermittently. Histopathologically, the localization of obliteration was mainly from small bronchi to membranous bronchioli with intermittent airway luminal obliteration in CoB, whereas the primary lesions in CDB revealed more continuous obliteration of the bronchiolar lumen than observed in CoB. In conclusion, this bronchial reconstruction study demonstrated marked morphological differences in the mechanisms of airway obliteration between two major morphologic subtypes of BO.

[A case of small-cell lung cancer associated with paraneoplastic limbic encephalitis during chemotherapy].

A 75-year-old woman received a diagnosis of small-cell lung cancer (T1N2M0, stage IIIA, limited disease) in January 2009. She received 4 cycles of chemotherapy with etoposide and carboplatin and concurrent radiotherapy (50 Gy/25 Fr) which yielded a complete response. However, recurrence of her small-cell lung cancer occurred in a mediastinal lymph node and the ribs in November 2009. During the 2nd cycle of second-line chemotherapy with nogitecan, she was readmitted to our hospital complaining of amnesia, periods of unconsciousness and convulsions. Her laboratory data on admission revealed normal serum electrolyte and cerebrospinal fluid levels, and electroencephalogram findings. Her neurological symptoms, which mimicked limbic encephalitis improved after steroid pulse therapy plus third-line chemotherapy with amrubicin. The final diagnosis was paraneoplastic limbic encephalitis by positive serum voltage-gated calcium channel antibodies. We hereby report a rare case of small-cell lung cancer associated with paraneoplastic limbic encephalitis during chemotherapy.

Eosinophilic bronchiolitis successfully treated with benralizumab.

A 53-year-old non-smoking Japanese woman was admitted to our hospital with a 20-year history of wet cough and dyspnoea on exertion. Bronchial asthma (BA) had been diagnosed 20 years earlier. Although she has been treated with high-dose inhaled corticosteroid, she had experienced frequent exacerbation of BA, and short-term oral corticosteroid bursts were occasionally administered. High-resolution CT of the chest revealed diffuse centrilobular nodules with bronchial wall thickening and patchy ground-glass opacities in both lungs. Lung biopsy specimens showed widespread cellular bronchiolitis with follicle formations in the membranous and respiratory bronchioles, accompanied by marked infiltration of plasma cells and eosinophils. In addition, immunohistochemical immunoglobulin G4 (IgG4) staining revealed many IgG4-positive plasma cells, and the ratio of IgG4-positive cells to IgG-positive cells exceeded 40%. The final diagnosis was eosinophilic bronchiolitis with marked IgG4-positive plasma cell infiltration in association with BA. With benralizumab therapy, her clinical condition dramatically improved.