Immunohistochemical Detection of Potential Microbial Antigens in Granulomas in the Diagnosis of Sarcoidosis.

Sarcoidosis may have more than a single causative agent, including infectious and non-infectious agents. Among the potential infectious causes of sarcoidosis, Mycobacterium tuberculosis and Propionibacterium acnes are the most likely microorganisms. Potential latent infection by both microorganisms complicates the findings of molecular and immunologic studies. Immune responses to potential infectious agents of sarcoidosis should be considered together with the microorganisms detected in sarcoid granulomas, because immunologic reactivities to infectious agents reflect current and past infection, including latent infection unrelated to the cause of the granuloma formation. Histopathologic data more readily support P. acnes as a cause of sarcoidosis compared with M. tuberculosis, suggesting that normally symbiotic P. acnes leads to granuloma formation in some predisposed individuals with Th1 hypersensitivity against intracellular proliferation of latent P. acnes, which may be triggered by certain host or drug-induced conditions. Detection of bacterial nucleic acids in granulomas does not necessarily indicate co-localization of the bacterial proteins in the granulomas. In the histopathologic diagnosis of sarcoidosis, M. tuberculosis-associated and P. acnes-associated sarcoidosis will possibly be differentiated in some patients by immunohistochemistry with appropriate antibodies that specifically react with mycobacterial and propionibacterial antigens, respectively, for each etiology-based diagnosis and potential antimicrobial intervention against sarcoidosis.

Hypersensitivity pneumonitis.

Hypersensitivity pneumonitis (HP) is a complex syndrome caused by the inhalation of a variety of antigens in susceptible and sensitized individuals. These antigens are found in the environment, mostly derived from bird proteins and fungi. The prevalence and incidence of HP vary widely depending on the intensity of exposure, the geographical area and the local climate. Immunopathologically, HP is characterized by an exaggerated humoral and cellular immune response affecting the small airways and lung parenchyma. A complex interplay of genetic, host and environmental factors underlies the development and progression of HP. HP can be classified into acute, chronic non-fibrotic and chronic fibrotic forms. Acute HP results from intermittent, high-level exposure to the inducing antigen, usually within a few hours of exposure, whereas chronic HP mostly originates from long-term, low-level exposure (usually to birds or moulds in the home), is not easy to define in terms of time, and may occur within weeks, months or even years of exposure. Some patients with fibrotic HP may evolve to a progressive phenotype, even with complete exposure avoidance. Diagnosis is based on an accurate exposure history, clinical presentation, characteristic high-resolution CT findings, specific IgG antibodies to the offending antigen, bronchoalveolar lavage and pathological features. Complete antigen avoidance is the mainstay of treatment. The pharmacotherapy of chronic HP consists of immunosuppressive drugs such as corticosteroids, with antifibrotic therapy being a potential therapy for patients with progressive disease.

Baseline High-Resolution CT Findings Predict Acute Exacerbation of Idiopathic Pulmonary Fibrosis: German and Japanese Cohort Study.

Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is a major cause of morbidity and death in IPF. However, sensitive predictive factors of AE-IPF have not been well-investigated. To investigate whether high-resolution computed tomographic (HRCT) abnormalities predict AE-IPF in independent ethnic cohorts, this study included 121 patients with IPF (54 German and 67 Japanese; mean age, 68.5 ± 7.6 years). Two radiologists independently visually assessed the presence and extent of lung abnormalities in each patient. Twenty-two (18.2%) patients experienced AE-IPF during the follow-up. The incidence of AE-IPF was significantly higher in the Japanese patients (n = 18, 26.9%) than in the German patients (n = 4, 7.3%, p < 0.01). In the Kaplan-Meier analysis, patients with a larger extent of ground glass opacity (GGO), fibrosis, and traction bronchiectasis experienced an earlier onset of AE-IPF (p = 0.0033, 0.0088, and 0.049, respectively). In the multivariate analysis, a larger extent of GGO and fibrosis on HRCT were independent predictors of AE-IPF (p = 0.026 and 0.037, respectively). Additionally, Japanese ethnicity was independently associated with the incidence of AE-IPF after adjustment for HRCT findings (p = 0.0074). In conclusion, a larger extent of GGO and fibrosis on HRCT and Japanese ethnicity appear to be risk factors for AE-IPF.

Utility of Anti-DSF70 Antibodies to Predict Connective Tissue Disease in Patients Originally Presenting with Idiopathic Interstitial Pneumonia.

BACKGROUND: Anti-DFS70 antibodies, corresponding to the dense fine speckled antinuclear antibody (ANA) pattern in HEp-2 substrates, have been observed in chronic inflammatory conditions, cancer and in healthy individuals but in only a small percentage of patients with connective tissue diseases (CTD). OBJECTIVES: The study was aimed to investigate the possible role of Anti-DFS70 antibodies to distinguish CTD associated interstitial lung disease (CTD-ILD) from idiopathic interstitial pneumonia (IIP) and to explore potential correlations between anti-DFS70 antibodies and clinical parameters. METHODS: Serum samples were collected from 49 healthy controls (HC), 35 scleroderma-ILD (SSc-ILD) patients as negative controls for anti-DFS70 antibody, and 260 patients with the initial diagnosis IIP including 100 nonspecific interstitial pneumonia (NSIP) and 160 idiopathic pulmonary fibrosis (IPF) patients. ANA pattern was identified by indirect immunofluorescence on HEp-2 cells and anti-DFS70 antibodies were measured in serum by ELISA. RESULTS: Serum anti-DFS70 antibodies were less frequently seen in ILD and SSc-ILD patients compared to HCs. Thirty-seven patients (34 initial idiopathic NSIP and 3 initial IPF patients) developed CTD during 24 months of follow-up, most of them combined with ANA positivity and anti-DFS70 antibody negativity. Anti-DFS70 antibody positivity was not significantly different between CTD-ILD and idiopathic ILD. CONCLUSIONS: The frequency of serum anti-DFS70 antibody is markedly decreased in patients with ILDs. Anti-DFS70 antibodies may be useful to predict CTD development in ILD patients.

Differential diagnosis of granulomatous lung disease: clues and pitfalls: Number 4 in the Series "Pathology for the clinician" Edited by Peter Dorfmüller and Alberto Cavazza.

Granulomatous lung diseases are a heterogeneous group of disorders that have a wide spectrum of pathologies with variable clinical manifestations and outcomes. Precise clinical evaluation, laboratory testing, pulmonary function testing, radiological imaging including high-resolution computed tomography and often histopathological assessment contribute to make a confident diagnosis of granulomatous lung diseases. Differential diagnosis is challenging, and includes both infectious (mycobacteria and fungi) and noninfectious lung diseases (sarcoidosis, necrotising sarcoid granulomatosis, hypersensitivity pneumonitis, hot tub lung, berylliosis, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, rheumatoid nodules, talc granulomatosis, Langerhans cell histiocytosis and bronchocentric granulomatosis). Bronchoalveolar lavage, endobronchial ultrasound-guided transbronchial needle aspiration, transbronchial cryobiopsy, positron emission tomography and genetic evaluation are potential candidates to improve the diagnostic accuracy for granulomatous lung diseases. As granuloma alone is a nonspecific histopathological finding, the multidisciplinary approach is important for a confident diagnosis.

Serum YKL-40 is a reliable biomarker for pulmonary alveolar proteinosis.

BACKGROUND AND OBJECTIVE: Pulmonary alveolar proteinosis (PAP) is a rare disease characterized by alveolar filling. YKL-40, a chitinase-like protein produced by macrophages and epithelial cells, is increased in patients with interstitial lung diseases. We aimed to evaluate the role of YKL-40 as a biomarker for PAP. METHODS: A total of 34 patients with autoimmune PAP and 50 healthy controls were studied. YKL-40 was measured by ELISA in serum and bronchoalveolar lavage fluid (BALF). Chitinase coding gene polymorphisms (CHI3L1-329 and -131) were detected by PCR and pyrosequencing. Correlations between serum YKL-40 levels and disease outcome were analysed. RESULTS: Baseline serum and BALF levels of YKL-40 were higher in PAP patients than in controls (286 ± 27 ng/mL vs 42 ± 4 ng/mL, P < 0.0001; 323 ± 36 ng/mL vs 3 ± 1 ng/mL, P < 0.0001, respectively). Serum YKL-40 levels correlated with diffusing capacity of the lung for carbon monoxide (DLCO ) at baseline (P = 0.002) and over time (P < 0.0001). Patients with disease progression had higher baseline serum YKL-40 levels than those who remained stable or improved (P < 0.0001). A baseline cut-off level of 300 ng/mL was predictive of disease progression (HR (hazard ratio): 7.875, P = 0.001). The presence of the G allele was associated with higher serum and BALF levels of YKL-40. CONCLUSION: YKL-40 is elevated in serum and BALF of PAP patients, and may be of clinical utility to predict outcome in PAP.

FAM13A polymorphism as a prognostic factor in patients with idiopathic pulmonary fibrosis.

BACKGROUND: Family with sequence similarity 13, member A (FAM13A) variants have been associated with susceptibility to chronic lung diseases. A recent genome-wide association study has shown an association between a polymorphism in FAM13A rs2609255 and idiopathic interstitial pneumonias in a Caucasian population. However, the relationship between rs2609255 polymorphism and prognosis in idiopathic interstitial pneumonias has not been investigated. METHODS: Sixty-five patients with idiopathic pulmonary fibrosis (IPF) and 310 Japanese healthy volunteers were enrolled in this study. Genomic DNA was extracted from all subjects. rs2609255 was genotyped by a commercially available assay. The correlations between rs2609255 polymorphism and survival and the occurrence of acute exacerbation were evaluated. RESULTS: The frequency of the minor G allele was significantly higher in IPF patients (59.2%) than in controls (41.9%; OR = 1.78, 95% CI; 1.29-2.44, p < 0.001). The rs2609255 major T allele was associated with lower diffusing capacity of carbon monoxide values and higher composite physiologic index after adjustment for age, sex and smoking (ß = -7.20, p = 0.005 and ß = 5.59, p = 0.009, respectively). In the Kaplan-Meier analysis, the T allele carriers showed a significantly increased mortality compared to the non-carriers (p < 0.05). In the multivariate Cox-proportional hazards analysis, the T allele of rs2609255 was independently associated with poor survival (hazard ratio, 5.37; p = 0.031; 95% confidence interval, 1.16-24.82). CONCLUSIONS: FAM13A gene polymorphism showed a significant association with the susceptibility to IPF, with severity of lung function impairment and with poor prognosis.

Serum YKL-40 as predictor of outcome in hypersensitivity pneumonitis.

YKL-40, a chitinase-like protein mainly secreted by macrophages, neutrophils and epithelial cells, is increased in patients with idiopathic interstitial pneumonia and sarcoidosis. We aimed to investigate the role of YKL-40 as a biomarker in hypersensitivity pneumonitis (HP).72 HP patients, 100 interstitial lung disease (ILD) controls and 60 healthy controls were studied. YKL-40 was measured by ELISA in serum and bronchoalveolar lavage fluid (BALF) at baseline and follow-up. The relationship between YKL-40 levels, clinical variables and disease outcome was evaluated.Baseline serum YKL-40 levels were significantly higher in HP patients than in healthy controls (p<0.001), but lower than in patients with other ILDs. Baseline BALF YKL-40 levels in HP patients were the highest among ILD patients. In HP patients, serum YKL-40 correlated with the diffusing capacity of the lung for carbon monoxide at baseline (p<0.01) and over time (p<0.001). HP patients whose disease progressed or who died had higher baseline YKL-40 levels than those who remained stable and survived (p<0.001). At a cut-off of 119 ng·mL-1, the baseline serum YKL-40 level predicted disease progression (hazard ratio 6.567; p<0.001), and at a cut-off of 150 ng·mL-1 was associated with mortality (hazard ratio 9.989; p<0.001).Serum YKL-40 may be a useful prognostic biomarker in HP patients.

MUC1 gene polymorphisms are associated with serum KL-6 levels and pulmonary dysfunction in pulmonary alveolar proteinosis.

BACKGROUND: KL-6, a human MUC1 mucin, is a sensitive biomarker for interstitial lung diseases including pulmonary alveolar proteinosis (PAP). A correlation between MUC1 gene single nucleotide polymorphism (SNP) rs4072037 genotype and serum KL-6 levels has been reported. This study was aimed at investigating the correlation between MUC1 SNP genotype, severity of disease and disease outcome in PAP. METHODS: Twenty four patients with PAP and 30 healthy volunteers were studied. MUC1 rs4072037 was detected by using a real-time polymerase chain reaction (RT-PCR). Genotyping was performed by pyrosequencing. KL-6 levels were measured in serum by Nanopia KL-6 assay (SEKISUI Diagnostics). RESULTS: The frequency of MUC1 rs4072037 alleles was significantly different between PAP patients and healthy volunteers (PAP, A/A 46%, A/G 54%, G/G 0%; healthy controls, A/A 30%, A/G 40%, G/G 30%; p = 0.013). Serum KL-6 levels were significantly higher in PAP patients than in controls (p < 0.0001), and significantly higher in PAP patients with A/A genotype than in those with A/G genotype (p = 0.007). Patients with A/A genotype had higher alveolar-arterial oxygen difference (A-aDO2) and lower DLco compared to those with A/G genotype (p = 0.027 and p = 0.012, respectively). Multivariate analysis, Kaplan-Meier analysis and C statistics showed that the rs4072037 A/A genotype was associated with higher rate of disease progression (HR: 5.557, p = 0.014). CONCLUSIONS: MUC1 rs4072037 A/A genotype is associated with more severe pulmonary dysfunction and a higher rate of disease progression in PAP patients.

MUC5B promoter polymorphism in Japanese patients with idiopathic pulmonary fibrosis.

BACKGROUND AND OBJECTIVE: A single nucleotide polymorphism (SNP) rs35705950 in the promoter of Mucin 5B (MUC5B) has been reported to be associated with idiopathic pulmonary fibrosis (IPF) mainly in Caucasian populations. This study was conducted to confirm the association between rs35705950 and IPF in a Japanese population. METHODS: Genomic DNA was extracted from blood samples in 384 Japanese and 137 German subjects, and rs35705950 was detected by commercially available genotyping assay. RESULTS: The genotype distributions of rs35705950 in Japanese patients with IPF, nonspecific interstitial pneumonia (NSIP) and healthy subjects (HS) were significantly different from those in the German counterparts (P < 0.001, P < 0.001 and P = 0.010, respectively). The rs35705950 T allele frequencies in patients with IPF, NSIP and HS were 3.4%, 1.7% and 0.8%, respectively in the Japanese, while they were 33.1%, 27.4% and 4.3%, respectively in the German cohort. The T allele frequencies in patients with IPF were significantly higher than those in HS both in the Japanese (P = 0.031) and German (P < 0.001) cohorts. CONCLUSIONS: The association between rs35705950 and IPF was also present in this Japanese cohort, but was not as strong as the German counterpart. To our knowledge, this is the first study to successfully validate the association between rs35705950 and IPF in a Japanese ethnicity.

A pilot study: a combined therapy using polymyxin-B hemoperfusion and extracorporeal membrane oxygenation for acute exacerbation of interstitial pneumonia.

BACKGROUND: Direct hemoperfusion with polymyxin B-immobilized fiber (PMX-DHP) might be beneficial for treating acute exacerbation (AE) of interstitial pneumonia (IP). Venovenous extracorporeal membranous oxygenation (VV-ECMO) is an emerging tool to avoid ventilator-induced lung injury. This is a report presenting the first three patients with AE of IP treated with a combined therapy of PMX-DHP and VV-ECMO. CASE PRESENTATION: Patient 1 was a 68-year-old male with acute interstitial pneumonia, patient 2 a 67-year-old male with AE of idiopathic pulmonary fibrosis, and patient 3 a 61-year-old female with AE of collagen vascular disease-associated interstitial pneumonia. All patients were severely hypoxemic and required mechanical ventilation. A combined therapy using PMX-DHP and VV-ECMO was initiated with support of intravenous corticosteroids and antibiotics. Radiological findings, oxygenation and laboratory findings markedly improved and all patients survived without severe complications. CONCLUSION: A combined therapy of PMX-DHP and VV-ECMO might be a therapeutic option for AE of IP.

Baseline KL-6 predicts increased risk for acute exacerbation of idiopathic pulmonary fibrosis.

BACKGROUND: Acute exacerbation (AE) is a major cause of death in idiopathic pulmonary fibrosis (IPF). However, little is known about sensitive biomarkers for predicting AE. The aim of our study was to investigate the significance of KL-6 and CC-Chemokine Ligand 18 (CCL18) as predictors for AE of IPF. METHODS: We prospectively collected a total of 77 patients with IPF. Serum levels of KL-6 and CCL18 were measured by ELISA. The correlation between baseline serum levels of the markers and the incidence of AE was evaluated. RESULTS: Thirteen (17%) patients experienced AE during follow-up. Baseline serum KL-6 levels were significantly higher in patients who developed AE than in patients with stable IPF (p < 0.0001), whereas serum CCL18 levels showed no difference between these groups (p = 0.13). At a cut-off level of 1300 U/mL for KL-6, the sensitivity, specificity, accuracy and likelihood ratio to predict AE were 92%, 61%, 66% and 2.36, respectively. In the Kaplan-Meier analysis, patients with baseline serum KL-6 level ≥1300 U/mL experienced earlier onset of AE (p = 0.002), whereas CCL18 showed no predictive value (p = 0.11). In the multivariate analysis, baseline serum KL-6 (both continuous and at a cut-off level of ≥1300 U/mL) was an independent predictive factor for AE after adjustment for age, sex, smoking history and %vital capacity (hazard ratio = 1.001, 18.8; p = 0.010, 0.008, respectively). CONCLUSIONS: Baseline serum KL-6 level is a sensitive predictor for the onset of AE in IPF.

Differences in serum SP-D levels between German and Japanese subjects are associated with SFTPD gene polymorphisms.

BACKGROUND: Surfactant protein A (SP-A) and SP-D are clinically established in Japan as serum biomarkers for diagnosing interstitial lung diseases (ILDs). Serum SP-D levels are affected by genetic variants. We conducted the present study to examine whether serum SP-A and/or SP-D levels in healthy subjects (HS) and patients with ILDs differ between populations with different genetic backgrounds. METHODS: German subjects (n = 303; 138 patients with idiopathic interstitial pneumonias [IIPs] and 165 HS) and Japanese subjects (n = 369; 94 patients with IIPs and 275 HS) were enrolled. Serum SP-A and SP-D levels were measured using an enzyme-linked immunosorbent assay, and four single-nucleotide polymorphisms (SNPs) in the SFTPD gene were genotyped using genomic DNA extracted from blood samples. RESULTS: In both the German and Japanese cohorts, serum SP-A and SP-D levels were significantly higher in patients with IIPs than in HS. There were no significant differences in SP-A levels between the German and Japanese cohorts; however, we found that serum SP-D levels were significantly higher in the German cohort, both in patients with IIPs and in HS (p < 0.001 and p = 0.005, respectively). Furthermore, the genotype distributions of the four SNPs in the SFTPD gene (rs721917, rs1998374, rs2243639, and rs3088308) were significantly different between German and Japanese cohorts (p < 0.001, p < 0.001, p = 0.022, and p < 0.001, respectively), and univariate linear regression analyses revealed that the genotypes of rs721917, rs1998374, and rs2243639 significantly correlated with serum SP-D levels (p < 0.001, p < 0.001, and p = 0.011, respectively). Furthermore, multivariate analyses revealed that the genotypes of these three SNPs correlated independently with serum SP-D levels (p < 0.001, p = 0.001, and p = 0.038, respectively), whereas ethnicity did not significantly correlate with serum SP-D levels. CONCLUSIONS: In patients with IIPs and HS, serum SP-D, but not SP-A, levels were significantly higher in the German than in the Japanese cohort, in part, because of the different frequencies of SFTPD gene polymorphisms.

CCL18 in serum, BAL fluid and alveolar macrophage culture supernatant in interstitial lung diseases.

BACKGROUND: CCL18 is a CC chemokine produced mainly by antigen-presenting cells, and is chemotactic predominantly for T-lymphocytes. CCL18 can stimulate pulmonary fibroblasts and increase the collagen production in vitro. OBJECTIVES: This study aimed to compare the CCL18 levels in a variety of human biological fluids between various interstitial lung diseases (ILDs), and to reveal potential correlations with BAL cell differentials. METHODS: Serum and bronchoalveolar lavage fluid (BALF) samples were collected from 199 patients with idiopathic pulmonary fibrosis (IPF), idiopathic non-specific interstitial pneumonia (iNSIP), respiratory bronchiolitis interstitial lung disease/desquamative interstitial pneumonia (RB-ILD/DIP), cryptogenic organizing pneumonia (COP), hypersensitivity pneumonitis (HP) or sarcoidosis. Alveolar macrophage (AM) culture was performed in 44 patients with IPF, iNSIP, COP, HP, sarcoidosis or non-ILDs. The CCL18 levels in serum, BALF and AM culture supernatant were measured with ELISA. RESULTS: Both serum and BALF CCL18 levels in all ILDs were higher than in controls (all p < 0.005). In HP, CCL18 serum levels were the highest of all ILDs, and its BALF levels were significantly higher than in other ILDs except iNSIP. The BALF CCL18 levels markedly correlated with BAL cell differentials, especially with the percentage of BAL lymphocytes. In AM culture supernatant, the spontaneous CCL18 production was higher in HP and COP than in IPF and controls. CONCLUSION: CCL18 levels in serum, BALF and AM culture supernatant are markedly increased in various inflammatory and fibrotic ILDs. However, the CCL18 level being highest in HP among the investigated ILDs suggests that CCL18 may be more profoundly involved in inflammatory immune responses.

Serum KL-6 is a predictor of outcome in pulmonary alveolar proteinosis.

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is a rare disorder characterised by abundant alveolar accumulation of surfactant lipoproteins. Serum levels of KL-6, high molecular weight human MUC1 mucin, are increased in the majority of patients with PAP. The prognostic significance of KL-6 in PAP is still unknown. Aim of the study was to evaluate whether serum KL-6 levels correlate with the outcome of the disease. PATIENTS AND METHODS: From 2006 to 2012, we prospectively studied 33 patients with primary autoimmune PAP. We measured serum KL-6 levels by ELISA (Eisai, Tokyo, Japan), and evaluated the correlation between initial KL-6 levels and clinical variables. Disease progression was defined as deterioration of symptoms, and/or lung function, and/or chest imaging. MAIN RESULTS: The initial serum KL-6 levels were significantly correlated with the baseline PaO2, A-aDO2, DLCO, VC and TLC (p=0.042, 0.012, 0.012, 0.02 and 0.013, respectively). The change over time of serum KL-6 correlated with the change over time of DLCO (p=0.017). The initial serum KL-6 levels were significantly higher in patients with disease progression than in those with remission (p<0.001). At a cut-off level of 1526 U/mL, the initial serum KL-6 level predicted disease progression (Se 81%, Sp 94%). At a cut-off level of 2157 U/mL, the initial serum KL-6 predicted the necessity of repeated whole lung lavage (Se 83%, Sp 96%). In the multivariate analysis, the initial serum level of KL-6 was the strongest predictor of disease progression (HR 9.41, p=0.008). CONCLUSIONS: Serum KL-6 seems to predict outcome in PAP.

Macrolides inhibit cytokine production by alveolar macrophages in bronchiolitis obliterans organizing pneumonia.

BACKGROUND AND OBJECTIVE: Bronchiolitis obliterans organizing pneumonia (BOOP) is a distinct clinicopathological entity histologically characterized by intra-alveolar granulation tissue and absence of extensive fibrotic lesions. Effective macrolide treatment of BOOP has been reported anecdotally. This study aimed to investigate whether alveolar macrophages (AMs) produce aberrant proinflammatory cytokines in BOOP and whether this can be inhibited by clarithromycin (CAM) or azithromycin (AZM). METHODS: AMs collected by bronchoalveolar lavage (BAL) from 6 BOOP patients and 8 non-ILD controls were cultured for 24h in the presence or absence of CAM, AZM, lipopolysaccharide (LPS), or dexamethasone (DEX). Tumor necrosis factor alpha (TNF-α), soluble TNF receptor 1 (sTNFR1), sTNFR2, interleukin 1beta (IL-1ß), IL-6, IL-8, IL-10, interferon gamma inducible protein 10 (IP-10) and CC chemokine ligand 18 (CCL18) were measured in the culture supernatant by ELISA. RESULTS: The spontaneous and LPS-stimulated production of all investigated cytokines by AMs was significantly increased in BOOP compared to controls. CAM and AZM induced a dose-dependent suppression of spontaneous TNF-α, sTNFR2, IL-6, IL-8 and CCL18 production (p<0.05). CAM also inhibited the IL-1ß production. CAM and AZM significantly and dose-dependently attenuated the LPS-stimulated production of sTNFR1, sTNFR2, IL-8 and CCL18 (p<0.05). CAM also inhibited the LPS-stimulated TNF-α, IL-1ß, IL-6 and IL-10 production. CONCLUSIONS: AMs from BOOP patients produce abundant proinflammatory cytokines which may be pivotal in the disease pathogenesis. Macrolides inhibit this cytokine production, CAM more efficiently than AZM.

KL-6, a Human MUC1 Mucin, as a prognostic marker for diffuse alveolar hemorrhage syndrome.

BACKGROUND: Diffuse alveolar hemorrhage syndrome is a life threatening condition with diverse etiologies. Sensitive prognostic markers for diffuse alveolar hemorrhage have not been well investigated. Serum KL-6 is a biomarker for various interstitial lung disease associated with disease activity and prognosis. The purpose of the present study was to evaluate the clinical utility of serum KL-6 level as a prognostic marker for diffuse alveolar hemorrhage. METHODS: We retrospectively collected 41 consecutive patients clinically diagnosed as having diffuse alveolar hemorrhage who were admitted to the Intensive Care Unit of Hiroshima University Hospital between 2004 and 2011. Correlation between prognosis and age, sex, laboratory findings including serum KL-6, radiological findings, ventilatory modes or therapeutic regimens were evaluated. RESULTS: Baseline and peak serum KL-6 levels were significantly higher in non-survivors compared with survivors. An increase in KL-6 levels during the initial week was associated with a subsequent deterioration of the oxygenation index. Higher baseline KL-6 levels and higher peak KL-6 levels were strongly correlated with death. With a cut-off level of 700 U/mL for peak KL-6, the sensitivity, specificity and accuracy for non-survival were 75%, 85% and 78%, respectively. In the multivariate analysis, only the peak KL-6 level ≥ 700 U/ml was an independent poor prognostic factor for diffuse alveolar hemorrhage. CONCLUSIONS: Peak serum KL-6 level ≥ 700 U/ml may become a clinically useful marker of poor prognosis for diffuse alveolar hemorrhage.

Hypersensitivity pneumonitis.

Clinical manifestations of hypersensitivity pneumonitis may closely mimic other interstitial lung diseases, and the disease onset is usually insidious. High-resolution computed tomography and bronchoalveolar lavage are the sensitive and characteristic diagnostic tests for hypersensitivity pneumonitis. The relevant antigen to hypersensitivity pneumonitis cannot be identified in up to 20% to 30% of patients. Clinicians should be aware that hypersensitivity pneumonitis must be considered in all cases of interstitial lung disease, and a detailed environmental exposure history is mandatory.

Different MUC1 gene polymorphisms in German and Japanese ethnicities affect serum KL-6 levels.

BACKGROUND: KL-6 is a high-molecular-weight glycoprotein classified as human Mucin-1 (MUC1). KL-6 has been reported to be a sensitive biomarker for interstitial lung diseases (ILDs) in the Japanese population. It is also known that polymorphisms in the MUC1 gene affect serum levels of KL-6. This study was conducted to evaluate serum levels of KL-6 and MUC1 polymorphisms in both German and Japanese populations. METHODS: Serum levels of KL-6 were measured in 267 patients with ILDs (152 German and 115 Japanese) and 186 healthy subjects (HS) (76 German and 110 Japanese). In addition, rs4072037 single nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction. The optimal cutoff values for discriminating patients with ILDs from HS was determined by receiver operating characteristic analysis based on ethnicity and rs4072037 genotypes. RESULTS: The serum KL-6 levels in patients with ILDs were significantly higher compared with HS in both the German and the Japanese cohorts (both p<0.001). The discriminating cutoff value of serum KL-6 in the German cohort was significantly higher than the value in the Japanese cohort. The difference in the serum levels of KL-6 was significantly associated with the rs4072037 genotype distribution. CONCLUSIONS: Even in the German cohort, the serum KL6 levels were significantly higher in patients with ILDs than HS. Because of differences in the genotype distribution of rs4072037, the KL-6 cutoff value for the German cohort that discriminated patients with ILDs from HS was significantly higher than the value in the Japanese cohort.

Localization of propionibacterium acnes in granulomas supports a possible etiologic link between sarcoidosis and the bacterium.

Sarcoidosis likely results from the exposure of a genetically susceptible subject to an environmental agent, possibly an infectious one. Mycobacterial and propionibacterial organisms are the most commonly implicated potential etiologic agents. Propionibacterium acnes is the only microorganism, however, found in sarcoid lesions by bacterial culture. To evaluate the pathogenic role of this indigenous bacterium, we screened for the bacterium in sarcoid and non-sarcoid tissues using immunohistochemical methods with novel P. acnes-specific monoclonal antibodies that react with cell-membrane-bound lipoteichoic acid (PAB antibody) and ribosome-bound trigger-factor protein (TIG antibody). We examined formalin-fixed and paraffin-embedded samples of lungs and lymph nodes from 196 patients with sarcoidosis, and corresponding control samples from 275 patients with non-sarcoidosis diseases. The samples were mostly from Japanese patients, with 64 lymph node samples from German patients. Immunohistochemistry with PAB antibody revealed small round bodies within sarcoid granulomas in 20/27 (74%) video-assisted thoracic surgery lung samples, 24/50 (48%) transbronchial lung biopsy samples, 71/81 (88%) Japanese lymph node samples, and 34/38 (89%) German lymph node samples. PAB antibody did not react with non-sarcoid granulomas in any of the 45 tuberculosis samples or the 34 samples with sarcoid reaction. In nongranulomatous areas, small round bodies detected by PAB antibody were found in alveolar macrophages of lungs and paracortical macrophages of lymph nodes from many sarcoid and some non-sarcoid patients. Large-spheroidal acid-fast bodies, Hamazaki-Wesenberg bodies, which were found in 50% of sarcoid and 15% of non-sarcoid lymph node samples, reacted with both PAB and TIG antibodies. Electron microscopy revealed that these Hamazaki-Wesenberg bodies had a single bacterial structure and lacked a cell wall with occasional protrusions from the body. The high frequency and specificity of P. acnes, detected by PAB antibody within sarcoid granulomas, indicates that this indigenous bacterium might be the cause of granuloma formation in many sarcoid patients.