Soluble form of the MDA5 protein in human sera.

Viral double-stranded RNA (dsRNA) is sensed by toll-like receptor 3 (TLR3) and retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs), including melanoma differentiation-associated gene 5 (MDA5). MDA5 recognizes the genome of dsRNA viruses and replication intermediates of single-stranded RNA viruses. MDA5 also plays an important role in the development of autoimmune diseases, such as Aicardi-Goutieres syndrome and type I diabetes. Patients with dermatomyositis with serum MDA5 autoantibodies (anti-CADM-140) are known to have a high risk of developing rapidly progressive interstitial lung disease and poor prognosis. However, there have been no reports on the soluble form of MDA5 in human serum. In the present study, we generated in-house monoclonal antibodies (mAbs) against human MDA5. We then performed immunohistochemical analysis and sensitive sandwich immunoassays to detect the MDA5 protein using two different mAbs (clones H27 and H46). As per the immunohistochemical analysis, the MDA5 protein was moderately expressed in the alveolar epithelia of normal lungs and was strongly expressed in the cytoplasm of lymphoid cells in the tonsils and acinar cells of the pancreas. Interestingly, soluble MDA5 protein was detectable in the serum, but not in the urine, of healthy donors. Soluble MDA5 protein was also detectable in the serum of patients with dermatomyositis. Immunoblot analysis showed that human cells expressed a 120 kDa MDA5 protein, while the 60 kDa MDA5 protein increased in the supernatant of peripheral mononuclear cells within 15 min after MDA5 agonist/double-strand RNA stimulation. Hydrogen deuterium exchange mass spectrometry revealed that an anti-MDA5 mAb (clone H46) bound to the epitope (415QILENSLLNL424) derived from the helicase domain of MDA5. These results indicate that a soluble MDA5 protein containing the helicase domain of MDA5 could be rapidly released from the cytoplasm of tissues after RNA stimulation.

Obesity may be a risk factor for transbronchial lung cryobiopsy-related adverse events in Japanese patients with interstitial lung disease.

BACKGROUND: Transbronchial lung cryobiopsy (TBLC) is known to be associated with a high incidence of adverse events. However, few studies have investigated the correlation between obesity and the risk of TBLC-related adverse events, especially in Asians, who are known to have characteristic differences in height and weight as compared to individuals of other ethnicities. METHODS: We retrospectively assessed 102 Japanese patients who underwent TBLC for the diagnosis of interstitial lung disease to evaluate the correlation between patient characteristics and the occurrence of TBLC-related adverse events (hemorrhage, pneumothorax, and acute exacerbation of interstitial lung disease). RESULTS: TBLC-related adverse events occurred in 19 patients (18.6 %), with hemorrhage being the most common adverse event (in 14 patients, 13.7 %). There was no correlation between age, sex, or pulmonary function test results and the occurrence of adverse events. The body mass index (BMI) cut-off predicting the occurrence of all adverse events was 26.6 kg/m2 (sensitivity of 0.389 and specificity of 0.852), and that predicting the occurrence of adverse events of hemorrhage was 26.8 kg/m2 (sensitivity of 0.462 and specificity of 0.907). Among patients with a BMI >26.8 kg/m2, adverse events of hemorrhage occurred in 37.5 % of cases, which was higher than among those with a BMI <26.8 kg/m2. CONCLUSIONS: Obesity is a risk factor for the incidence of TBLC-related adverse events, particularly adverse events of hemorrhage, in Japanese patients. The BMI cut-off values that predicted an increased frequency of TBLC-related adverse events and hemorrhage specifically were 26.6 and 26.8 kg/m2, respectively.

A prospective cohort study of periostin as a serum biomarker in patients with idiopathic pulmonary fibrosis treated with nintedanib.

This study investigated the utility of periostin, a matricellular protein, as a prognostic biomarker in patients with idiopathic pulmonary fibrosis (IPF) who received nintedanib. Monomeric and total periostin levels were measured by enzyme-linked immunosorbent assay in 87 eligible patients who participated in a multicenter prospective study. Forty-three antifibrotic drug-naive patients with IPF described in previous studies were set as historical controls. Monomeric and total periostin levels were not significantly associated with the change in forced vital capacity (FVC) or diffusing capacity of the lungs for carbon monoxide (DLCO) during any follow-up period. Higher monomeric and total periostin levels were independent risk factors for overall survival in the Cox proportional hazard model. In the analysis of nintedanib effectiveness, higher binarized monomeric periostin levels were associated with more favorable suppressive effects on decreased vital capacity (VC) and DLCO in the treatment group compared with historical controls. Higher binarized levels of total periostin were associated with more favorable suppressive effects on decreased DLCO but not VC. In conclusion, higher periostin levels were independently associated with survival and better therapeutic effectiveness in patients with IPF treated with nintedanib. Periostin assessments may contribute to determining therapeutic strategies for patients with IPF.

Periostin Is a Biomarker of Rheumatoid Arthritis-Associated Interstitial Lung Disease.

Periostin was investigated as a biomarker for rheumatoid arthritis-associated interstitial lung disease (RA-ILD). This prospective study measured serum monomeric and total periostin, Klebs von den Lungen-6 (KL-6), surfactant protein D (SP-D), and lactate dehydrogenase (LDH) in 19 patients with RA-ILD, 20 RA without ILD, and 137 healthy controls (HC). All biomarkers were higher in RA-ILD than HC or RA without ILD. KL-6 accurately detected ILD in RA patients (area under curve [AUC] = 0.939) and moderately detected SP-D and monomeric and total periostin (AUC = 0.803, =0.767, =0.767, respectively). Monomeric and total periostin were negatively correlated with normal lung area and positively correlated with honeycombing, reticulation, fibrosis score, and the traction bronchiectasis grade but not inflammatory areas. Serum levels of SP-D, KL-6, and LDH did not correlate with the extent of those fibrotic areas on high-resolution CT. Serum monomeric and total periostin were higher in patients with RA-ILD with definite usual interstitial pneumonia pattern compared with other ILD patterns. Immunohistochemical analyses of biopsy or autopsy lung tissues from RA-ILD during the chronic phase and acute exacerbation showed that periostin was expressed in fibroblastic foci but not inflammatory or dense fibrosis lesions. Periostin is a potential biomarker for diagnosis, evaluating fibrosis, and deciding therapeutic strategies for patients with RA-ILD.

Successful Treatment of a Patient with Drug-Refractory Rheumatoid Arthritis-Associated Interstitial Lung Disease with Upadacitinib: A Case Report.

Insufficient evidence exists regarding the efficacy of Janus kinase inhibitors (JAKis), a class of targeted synthetic disease-modifying anti-rheumatic drugs (tsDMARDs), in the treatment of rheumatoid arthritis (RA)-associated interstitial lung disease (ILD). Herein, we present a case of RA-ILD refractory to previous treatments that exhibited favorable response to upadacitinib. A 69-year-old man, former smoker, was diagnosed with RA-ILD based on persistent symmetric polyarthritis, elevated C-reactive protein levels and erythrocyte sedimentation rate, reduced diffusing capacity for carbon monoxide/alveolar volume (DLCO 69.9%), and bilateral ground-glass attenuation with traction bronchiectasis, predominantly in the lower lung lobe. Initial treatment with oral prednisolone and methotrexate was started; however, the patient showed worsening dyspnea, chest high-resolution computed tomography abnormalities, and decreased pulmonary function. The dose of prednisolone was increased, and methotrexate was shifted to tacrolimus; however, tacrolimus was eventually discontinued because of renal dysfunction. Subsequent treatment changes included abatacept followed by intravenous cyclophosphamide, but ILD activity continued to worsen and met the criteria of progressive pulmonary fibrosis. Approximately 4.5 years after the RA diagnosis, dyspnea, radiological abnormalities, and DLCO improved following treatment switch to upadacitinib, one of JAKis. JAKi therapy may have potential as a treatment option for refractory RA-ILD.

Combination of Prednisolone and Calcineurin Inhibitors Prevents Lung Function Decline in Patients with Anti-aminoacyl-tRNA Synthetase Antibody-Positive Polymyositis/Dermatomyositis.

OBJECTIVE: Anti-aminoacyl-tRNA synthetase antibody-positive polymyositis/dermatomyositis-associ ated interstitial lung disease (ARS-ILD) has a good prognosis, with few cases progressing to respiratory failure. This study aimed to determine factors predictive of lung function changes in patients with ARS-ILD. METHODS: We retrospectively studied 49 patients with ARS-ILD treated at Kurume University Hospital Hospital between 2000 and 2018. We followed 30 patients for more than 2 years after prednisolone (PSL) therapy, with or without calcineurin inhibitors (CNIs), evaluating clinical, physiological, computed tomography, pulmonary func tion, and serological data. RESULTS: After treatment for 24 months, no significant differences were noted between clinical parameters and improvement in forced vital capacity (FVC), %FVC, % carbon monoxide diffusing capacity/alveolar volume (%DLCO), and %DLCO/alveolar volume. Conversely, the annual change of %FVC significantly correlated with the Medical Research Council dyspnea scale grade and %FVC at the first visit and treatment. Furthermore, the annual change of %DLCO/VA significantly correlated with the duration from the first visit to treatment initiation. CONCLUSION: Compared with PSL monotherapy, combining PSL and CNI showed greater mitigation of %FVC decline. The time from onset of ARS-ILD to the first visit is critical for preventing a decline in lung function, and as such, patients should be monitored carefully.

Clinical significance of high monocyte counts for the continuous treatment with nintedanib.

BACKGROUND: Nintedanib is now widely used to treat interstitial lung disease (ILD). Adverse events, which occur in not a few patients, make it difficult to continue nintedanib treatment, but the risk factors for adverse events are not well understood. METHODS: In this retrospective cohort study, we enrolled 111 patients with ILDs treated with nintedanib and investigated the factors involved in starting dosage reduction, withdrawal, or discontinuation within 12 months, even with appropriate symptomatic treatment. We also examined the efficacy of nintedanib in reducing the frequency of acute exacerbations and the prevention of pulmonary function reduction. RESULTS: Patients with high monocyte counts (> 0.454 × 109/L) had a significantly higher frequency of treatment failure, such as dosage reduction, withdrawal, or discontinuation. High monocyte count was as significant a risk factor as body surface area (BSA). Regarding efficacy, there was no difference in the frequency of acute exacerbations or the amount of decline in pulmonary function within 12 months between the normal (300 mg) and reduced (200 mg) starting dosage groups. CONCLUSION: Our study results indicate that patients with higher monocyte counts (> 0.454 × 109/L) should very careful about side effects with regard to nintedanib administration. Like BSA, a higher monocyte count is considered a risk factor for nintedanib treatment failure. There was no difference in FVC decline and frequency of acute exacerbations between the starting doseage of nintedanib, 300 mg and 200 mg. Considering the risk of withdrawal periods and discontinuation, a reduced starting dosage may be acceptable in the patients with higher monocyte counts or small body sizes.

The Characteristic of Transbronchial Lung Cryobiopsy in the Pathological Diagnosis of Hypersensitivity Pneumonitis.

BACKGROUND: Transbronchial lung cryobiopsy (TBLC) has widely used for the diagnosis of diffuse lung disease. However, it remains unclear whether TBLC is useful for the diagnosis in hypersensitivity pneumonitis (HP). METHODS: We investigated 18 patients who underwent TBLC and were diagnosed with HP based on pathology or multidisciplinary discussion (MDD). Of the 18 patients, 12 had fibrotic HP (fHP), 2 had non-fibrotic HP (non-fHP) diagnosed with MDD. The remaining 4 patients were diagnosed with fHP by pathology but not by MDD because of clinical features. The radiology and pathology of these cases were compared. RESULTS: All patients with fHP showed radiological findings of inflammation, fibrosis, and airway disease. Conversely, pathology showed fibrosis and inflammation in 11 of 12 cases (92%), but airway disease was significantly less common with 5 cases (42%) (p = 0.014). Non-fHP showed inflammatory cell infiltration mainly in the centrilobule on pathology, which was consistent with radiology. Granulomas were found in 5 patients with HP (36%). In the non-HP group, airway-centered interstitial fibrosis was observed in 3 patients (75%) with pathology. CONCLUSIONS: The pathology with TBLC is difficult to evaluate airway disease of HP. We need to understand this characteristic of TBLC to make a MDD diagnosis of HP.

Effect of the 2020 hypersensitivity pneumonitis guideline on the pathologic diagnosis of interstitial pneumonia.

It was reported that the 2020 guideline for hypersensitivity pneumonitis (HP) might result in the overdiagnosis of fibrotic HP (fHP). fHP and other types of interstitial pneumonias have several overlapping characteristics, and a high diagnostic concordance rate of fHP is rarely obtained. Therefore, we investigated the impact of the 2020 HP guideline on the pathological diagnosis of cases previously diagnosed as interstitial pneumonia. We identified 289 fibrotic interstitial pneumonia cases from 2014 to 2019 and classified them into four categories according to the 2020 HP guideline: typical, probable, and indeterminate for fHP and alternative diagnosis. The original pathological diagnosis of 217 cases were compared to their classification as either typical, probable, or indeterminate for fHP according to the 2020 guideline. The clinical data, including serum data and pulmonary function tests, were compared among the groups. Diagnoses changed from non-fHP to fHP for 54 (25%) of the 217 cases, of which, 8 were typical fHP and 46 were probable fHP. The ratio of typical and probable fHP cases to the total number of VATS cases was significantly lower when using transbronchial lung cryobiopsy (p < 0.001). The clinical data of these cases bore a more remarkable resemblance to those diagnosed as indeterminate for fHP than to those diagnosed as typical or probable. The pathological criteria in the new HP guidelines increase the diagnosis of fHP. However, it is unclear whether this increase leads to overdiagnosis, and requires further investigation. Transbronchial lung cryobiopsy may not be helpful when using the new criteria to impart findings for fHP diagnosis.

Enhanced immune complex formation in the lungs of patients with dermatomyositis.

BACKGROUND: Interstitial lung disease is frequently comorbid with dermatomyositis and has a poor prognosis, especially in patients with the anti-melanoma differentiation-associated gene 5 (MDA5) autoantibody. However, the pathogenesis of dermatomyositis-related interstitial lung disease remains unclear. METHODS: We examined 18 and 19 patients with dermatomyositis-related interstitial lung disease and idiopathic pulmonary fibrosis (control), respectively. Lung tissues obtained from these patients were semi-quantitatively evaluated by immunohistochemical staining with in-house anti-human MDA5 monoclonal antibodies, as well as anti-human immunoglobulin (Ig) G, IgM, IgA, and complement component 3(C3) antibodies. We established human MDA5 transgenic mice and treated them with rabbit anti-human MDA5 polyclonal antibodies, and evaluated lung injury and Ig and C3 expression. RESULTS: MDA5 was moderately or strongly expressed in the lungs of patients in both groups, with no significant differences between the groups. However, patients with dermatomyositis-related interstitial lung disease showed significantly stronger expression of C3 (p < 0.001), IgG (p < 0.001), and IgM (p = 0.001) in the lungs than control. Moreover, lung C3, but IgG, IgA, nor IgM expression was significantly stronger in MDA5 autoantibody-positive dermatomyositis-related interstitial lung disease (n = 9) than in MDA5 autoantibody-negative dermatomyositis-related interstitial lung disease (n = 9; p = 0.022). Treatment with anti-MDA5 antibodies induced lung injury in MDA5 transgenic mice, and strong immunoglobulin and C3 expression was observed in the lungs of the mice. CONCLUSION: Strong immunoglobulin and C3 expression in the lungs involve lung injury related to dermatomyositis-related interstitial lung disease. Enhanced immune complex formation in the lungs may contribute to the poor prognosis of MDA5 autoantibody-positive dermatomyositis-related interstitial lung disease.

Granulomatous Lymphocytic Interstitial Lung Disease in Multiple Myeloma.

An 82-year-old woman complained of recurring cough and shortness of breath and was diagnosed with progressive multiple myeloma (MM). Chest computed tomography (CT) revealed bilateral ground-glass opacity and interlobular septal thickening predominantly in the lower lung zones. Histopathologic findings obtained by a transbronchial lung cryobiopsy (TBLC) revealed alveolitis and granulomas consistent with granulomatous-lymphocytic interstitial lung disease (GLILD). Aggressive chemotherapy for MM contributed to the improvement in respiratory symptoms and abnormal chest CT findings. In cases of MM with lung abnormalities, the possibility of GLILD must be ruled out, and a TBLC should be considered to attain an accurate diagnosis.

A Rare Case of Diffuse Bilateral Minute Pulmonary Meningothelial-like Nodules Increasing over the Short Term and Resembling Metastatic Lung Cancer.

A 54-year-old woman was referred to our hospital because computed tomography (CT) revealed multiple lung nodules during a health checkup. The nodules were up to 5 mm in diameter and randomly distributed in both lungs, appearing ring-shaped. No clinical symptoms were present. However, the nodes proliferated, and multiple lung metastases could not be ruled out, so a biopsy was performed to establish a diagnosis. She was diagnosed with minute pulmonary meningothelial-like nodules (MPMNs), and her condition had not deteriorated at the latest follow-up. Although rare, MPMNs can proliferate for a short time, but a biopsy to exclude malignant causes is essential.

Clinical significance of interstitial lung abnormalities and immune checkpoint inhibitor-induced interstitial lung disease in patients with non-small cell lung cancer.

BACKGROUND: Interstitial lung abnormalities (ILAs) are known to be a risk of drug-induced pneumonitis. However, there are few reports on the relationship between ILAs and immune checkpoint inhibitor-related interstitial lung disease (ICI-ILD). We retrospectively investigated the clinical significance of ILAs in patients with non-small cell lung cancer (NSCLC) receiving ICIs. METHODS: We defined ILAs as nondependent abnormalities affecting more than 5% of any lung zone, including ground-glass or diffuse centrilobular nodularities, traction bronchiectasis, honeycombing, and nonemphysematous cysts. Early-onset ICI-ILD was defined as developing within 3 months after the initiation of ICI administration. RESULTS: Of 264 patients with advanced NSCLC, 57 patients (21.6%) had ILAs (43 fibrotic and 14 nonfibrotic ILAs). The difference between the incidence of ICI-ILD in patients with or without ILAs was not significant. Of 193 patients treated by ICI monotherapy, 18 (9.3%) developed early-onset ICI-ILD. Among patients receiving ICI monotherapy, the incidence of early-onset ICI-ILD was significantly higher in patients with than in patients without nonfibrotic ILAs. CONCLUSION: The presence of nonfibrotic ILAs is a significant risk for early-onset ICI-ILD in patients with NSCLC undergoing ICI monotherapy. Clinicians should be aware of ILAs, especially nonfibrotic ILAs, before administering ICIs to lung cancer patients.

Acute exacerbation of idiopathic pulmonary fibrosis after bivalent {tozinameran and famtozinameran} mRNA COVID-19 vaccination.

An 82-year-old man diagnosed with interstitial lung disease through computed tomography (CT) 1 year prior received a bivalent (tozinameran and famtozinameran) mRNA COVID-19 vaccine. He developed respiratory symptoms 1.5 months later, and chest high-resolution CT revealed new ground-glass opacities showing traction bronchiectasis. Transbronchial lung cryobiopsy revealed organizing acute lung injury and fibrosis with architectural destruction. The patient was diagnosed with an acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF). The bivalent mRNA COVID-19 vaccination was determined as the cause of the AE-IPF based on detailed medical history and examination findings. High-dose corticosteroid therapy improved the patient's symptoms and radiological findings.

Sensitivity of transbronchial lung cryobiopsy in the diagnosis of different interstitial lung diseases.

The accuracy of transbronchial lung cryobiopsy (TBLC) in each disease for pathological and multidisciplinary discussion (MDD) diagnosis is not yet established. METHOD: We investigated 431 patients who were classified by MDD diagnosis and were grouped into the disease categories. For each category or disease, we used TBLC samples to calculate the sensitivities of the pathological diagnosis compared with MDD diagnoses. Further, we compared these sensitivities to pathological diagnoses with all clinical/radiological information. RESULT: The sensitivity for diagnosing idiopathic interstitial pneumonia (IIPs) with TBLC was higher than connective tissue disease associated ILD (CTD-ILD). Idiopathic nonspecific interstitial pneumonia (iNSIP), fibrotic hypersensitivity pneumonitis, and some CTD-ILDs were diagnosed with lower sensitivities compared to IPF. The sensitivity of pathological diagnosis with all clinical/radiological information in IPF was higher than in iNSIP, but not significantly different from other diseases. The overall sensitivity of the pathological diagnosis with clinical/radiological information was 69.0%, significantly higher than without clinical/radiological information. CONCLUSION: The sensitivity of pathological diagnosis with TBLC was low for some diseases except IPF. The addition of all clinical/radiological information increased the sensitivity of pathology diagnosis by TBLC, which was no less sensitive than IPF for all diseases except iNSIP.

Positive Autoantibody Is Associated with Malignancies in Patients with Idiopathic Interstitial Pneumonias.

Various autoantibodies are associated with clinical outcomes in patients with idiopathic interstitial pneumonias (IIPs). We retrospectively analyzed the association between autoantibodies and malignancies in IIP patients. Comprehensive analyses of autoantibodies were performed using immunoprecipitation and enzyme-linked immunosorbent assays in 193 consecutive IIP patients. Cancer-related factors were analyzed using logistic regression analysis. In total, 22 of 193 patients (11.4%) with IIP had malignant disease. In univariate analysis, positivity for any autoantibody (odds ratio (OR), 3.1; 95% confidence interval (CI), 1.2-7.7; p = 0.017) and antinuclear antibody titer ≥1:320 (OR, 3.4; CI, 1.2-9.8; p = 0.024) were significantly associated with malignancies. Positive anti-aminoacyl tRNA synthetase (ARS) (OR, 3.7; CI, 0.88-15.5; p = 0.074) and anti-Ro52 antibody (OR, 3.2; CI, 0.93-11.2; p = 0.065) tended to be associated with malignancies. In multivariate analysis, independent risk factors were male sex (OR, 3.7; CI, 1.0-13.5; p = 0.029) and positivity for any autoantibody (OR, 3.9; CI, 1.5-10.1; p = 0.004) in model 1, and male sex (OR, 3.9; CI, 1.0-15.3; p = 0.049), antinuclear antibody titer ≥1:320 (OR, 4.2; CI, 1.4-13.3; p = 0.013), and positivity for anti-ARS antibody (OR, 6.5; CI, 1.2-34.1; p = 0.026) in model 2. Positivity for any autoantibody, antinuclear and anti-ARS antibodies, and male sex were independent risk factors for malignancies in IIP patients. Testing autoantibodies in IIP patients might help the early diagnosis of malignancies.

IgG4-related lung disease with a desquamative interstitial pneumonia pattern radiologically and pathologically.

A man in his 60s exhibited persistent dry cough and dyspnoea, which persisted even after smoking cessation. Chest high-resolution CT showed diffuse ground-glass opacities in the subpleural areas of both lungs. He underwent bronchoscopy, but no definitive diagnosis could be made. Histopathological analysis of the specimen obtained by surgical lung biopsy showed a desquamative interstitial pneumonia (DIP) pattern, with lymphocyte and plasma cell infiltrates in the alveolar septa; the ratio of IgG and IgG4-positive cells was more than 90%. He quit smoking, but the radiological findings worsened. Based on the pathological findings, we diagnosed the patient with DIP due to IgG4-related lung disease. Prednisolone was initiated, and the symptoms and radiological findings improved.

Recurrence of idiopathic pulmonary hemosiderosis in adults with childhood onset: A case report and literature review.

We describe a rare case of a 20-year-old Japanese man with idiopathic pulmonary hemosiderosis (IPH) recurrence in adults with childhood onset (racIPH). IPH commonly occurs in children, and data regarding racIPH are lacking. A review of the literature showed that only five cases of racIPH have been reported (including the present case) and that racIPH shows features that are intermediate between childhood- and adult-onset IPH with respect to age and a lower frequency of smoking history. We also found that the degree of anemia was usually not severe, and a favorable response to corticosteroid therapy is expected in racIPH.

Deep-Learning-Aided Detection of Mycobacteria in Pathology Specimens Increases the Sensitivity in Early Diagnosis of Pulmonary Tuberculosis Compared with Bacteriology Tests.

The histopathological diagnosis of mycobacterial infection may be improved by a comprehensive analysis using artificial intelligence. Two autopsy cases of pulmonary tuberculosis, and forty biopsy cases of undetected acid-fast bacilli (AFB) were used to train AI (convolutional neural network), and construct an AI to support AFB detection. Forty-two patients underwent bronchoscopy, and were evaluated using AI-supported pathology to detect AFB. The AI-supported pathology diagnosis was compared with bacteriology diagnosis from bronchial lavage fluid and the final definitive diagnosis of mycobacteriosis. Among the 16 patients with mycobacteriosis, bacteriology was positive in 9 patients (56%). Two patients (13%) were positive for AFB without AI assistance, whereas AI-supported pathology identified eleven positive patients (69%). When limited to tuberculosis, AI-supported pathology had significantly higher sensitivity compared with bacteriology (86% vs. 29%, p = 0.046). Seven patients diagnosed with mycobacteriosis had no consolidation or cavitary shadows in computed tomography; the sensitivity of bacteriology and AI-supported pathology was 29% and 86%, respectively (p = 0.046). The specificity of AI-supported pathology was 100% in this study. AI-supported pathology may be more sensitive than bacteriological tests for detecting AFB in samples collected via bronchoscopy.