Adherence to the GOLD Guideline in COPD Management of South Korea: Findings from KOCOSS Study 2011–2018 / 전남의대학술지

The guidelines for chronic obstructive pulmonary disease (COPD) treatment are important for the management of the disease. However, studies regarding the treatment adherence to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines have been scarce in Korea. Therefore, to examine the adherence to the GOLD guidelines, we examined the patterns of prescribed medication in COPD patients from 2011 to 2018. Patients were classified as having been appropriately and inappropriately treated (overtreatment or undertreatment) for the GOLD group. Appropriate medical therapy was defined as using the first choice or alternative choice drug recommended in the GOLD guidelines. Inappropriate therapy was classified as overtreatment or undertreatment in accordance with the categorization in the GOLD guidelines. According to treatment of 2011 GOLD guidelines, there was inappropriate treatment in 52.3% in group A, 47.3% in group B, 56.3% in group C, and 17.8% in group D. According to treatment of 2017 GOLD guidelines, there was inappropriate treatment in 66.7% in group A, 45.3% in group B, 14.3% in group C, and 24.0% in group D. The common type of inappropriate COPD treatment is overtreatment, with inhaled corticosteroid (ICS) containing regimens. In conclusions, adherence to the GOLD guideline by the pulmonologist in clinical practice is still low in Korea. Therefore, we need better strategies to both optimize the use of the guidelines and adhere to the guidelines as well.

Severe Cutaneous Adverse Reactions to Antiepileptic Drugs: A Nationwide Registry-Based Study in Korea

PURPOSE: Severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS) to antiepileptic drug (AED), are rare, but result in significant morbidity and mortality. We investigated the major culprit drugs, clinical characteristics, and clinical course and outcomes of AED-induced SCARs using a nationwide registry in Korea. METHODS: A total of 161 patients with AED-induced SCARs from 28 referral hospitals were analyzed. The causative AEDs, clinical characteristics, organ involvements, details of treatment, and outcomes were evaluated. We compared the clinical and laboratory parameters between SJS/TEN and DRESS according to the leading causative drugs. We further determined risk factors for prolonged hospitalization in AED-induced SCARs. RESULTS: Carbamazepine and lamotrigine were the most common culprit drugs causing SCARs. Valproic acid and levetiracetam also emerged as the major causative agents. The disease duration and hospital stay in carbamazepine-induced SJS/TEN were shorter than those in other AEDs (P< 0.05, respectively). In younger patients, lamotrigine caused higher incidences of DRESS than other drugs (P= 0.045). Carbamazepine, the most common culprit drug for SCARs, was associated with a favorable outcome related with prolonged hospitalization in SJS (odds ratio, 0.12; 95% confidence interval, 0.02-0.63, P= 0.12), and thrombocytopenia was found to be a risk factor for prolonged hospitalization in DRESS. CONCLUSION: This was the first large-scale epidemiological study of AED-induced SCARs in Korea. Valproic acid and levetiracetam were the significant emerging AEDs causing SCARs in addition to the well-known offending AEDs such as carbamazepine and lamotrigine. Carbamazepine was associated with reduced hospitalization, but thrombocytopenia was a risk factor for prolonged hospitalization. Our results suggest that the clinical characteristics and clinical courses of AED-induced SCARs might vary according to the individual AEDs.

Validation of Previous Spirometric Reference Equations and New Equations

Nonspecific Bronchoprovocation Test / 결핵및호흡기질환

Bronchial asthma is a disease characterized by the condition of airway hyper-responsiveness, which serves to produce narrowing of the airway secondary to airway inflammation and/or various spasm-inducing stimulus. Nonspecific bronchoprovocation testing is an important method implemented for the purpose of diagnosing asthma; this test measures the actual degree of airway hyper-responsiveness and utilizes direct and indirect bronchoprovocation testing. Direct bronchoprovocation testing using methacholine or histamine may have superior sensitivity as these substances directly stimulate the airway smooth muscle cells. On the other hand, this method also engenders the specific disadvantage of relatively low specificity. Indirect bronchoprovocation testing using mannitol, exercise, hypertonic saline, adenosine and hyperventilation serves to produce reactions in the airway smooth muscle cells by liberating mediators with stimulation of airway inflammatory cells. Therefore, this method has the advantage of high specificity and also demonstrates relatively low sensitivity. Direct and indirect testing both call for very precise descriptions of very specific measurement conditions. In addition, it has become evident that challenge testing utilizing each of the various bronchoconstrictor stimuli requires distinct and specific protocols. It is therefore important that the clinician understand the mechanism by which the most commonly used bronchoprovocation testing works. It is important that the clinician understand the mechanism of action in the testing, whether direct stimuli (methacholine) or indirect stimuli (mannitol, exercise) is implemented, when the testing is performed and the results interpreted.

Hypereosinophilic Syndrome Associated with the Onset of Rheumatoid Arthritis: A Case Report

Idiopathic hypereosinophilic syndrome (HES) is a disorder characterized by the sustained overproduction of eosinophils and multiple organ damage. Rheumatologic manifestations of HES are infrequent, but persistent eosinophilia is observed in approximately 10% to 40% of patients with rheumatoid arthritis (RA). This finding may be a result of the RA itself and is often associated with active disease and the presence of extra-articular features. We describe the case of a 48-year-old man affected by HES who subsequently developed RA. Both HES and RA responded rapidly to the corticosteroid and methotrexate therapy. In this patient, the initiation of RA and HES was related, suggesting a common pathogenetic link between these two diseases.

Clinical Effectiveness and Nephrotoxicity of Aerosolized Colistin Treatment in Multidrug-Resistant Gram-Negative Pneumonia / 대한구급학회지

BACKGROUND: Colistin (polymyxin E) is active against multidrug-resistant Gram-negative bacteria (MDR-GNB). However, the effectiveness of inhaled colistin is unclear. This study was designed to assess the effectiveness and safety of aerosolized colistin for the treatment of ventilator-associated pneumonia (VAP) caused by MDR-GNB. METHODS: In this retrospective longitudinal study, we evaluated the medical records of 63 patients who received aerosolized colistin treatment for VAP caused by MDR-GNB in the medical intensive care unit (MICU) from February 2012 to March 2014. RESULTS: A total of 25 patients with VAP caused by MDR-GNB were included in this study. The negative conversion rate was 84.6% after treatment, and acute kidney injury (AKI) occurred in 11 patients (44%, AKI group). The average length of MICU stay and colistin treatment- related factors, such as daily and total cumulative doses and administration period, were not significantly different between groups. In-hospital mortality tended to be higher in the AKI group (p = 0.07). Multivariate analysis showed that a body mass index less than 18 was an independent risk factor of mortality (odds ratio [OR] = 21.95, 95% confidence interval [CI] 1.59-302.23; p = 0.02). Notably, AKI occurrence was closely related to the administration of more than two nephrotoxic drugs combined with aerosolized colistin (OR = 15.03, 95% CI 1.40-161.76; p = 0.025) and septic shock (OR = 8.10, 95% CI 1.40-161.76; p = 0.04). CONCLUSIONS: The use of adjunctive aerosolized colistin treatment appears to be a relatively safe and effective option for the treatment of VAP caused by MDR-GNB. However, more research on the concomitant use of nephrotoxic drugs with aerosolized colistin will be necessary, as this can be an important risk factor of development of AKI.

Clinical Effectiveness and Nephrotoxicity of Aerosolized Colistin Treatment in Multidrug-Resistant Gram-Negative Pneumonia / 대한중환자의학회지

BACKGROUND: Colistin (polymyxin E) is active against multidrug-resistant Gram-negative bacteria (MDR-GNB). However, the effectiveness of inhaled colistin is unclear. This study was designed to assess the effectiveness and safety of aerosolized colistin for the treatment of ventilator-associated pneumonia (VAP) caused by MDR-GNB. METHODS: In this retrospective longitudinal study, we evaluated the medical records of 63 patients who received aerosolized colistin treatment for VAP caused by MDR-GNB in the medical intensive care unit (MICU) from February 2012 to March 2014. RESULTS: A total of 25 patients with VAP caused by MDR-GNB were included in this study. The negative conversion rate was 84.6% after treatment, and acute kidney injury (AKI) occurred in 11 patients (44%, AKI group). The average length of MICU stay and colistin treatment- related factors, such as daily and total cumulative doses and administration period, were not significantly different between groups. In-hospital mortality tended to be higher in the AKI group (p = 0.07). Multivariate analysis showed that a body mass index less than 18 was an independent risk factor of mortality (odds ratio [OR] = 21.95, 95% confidence interval [CI] 1.59-302.23; p = 0.02). Notably, AKI occurrence was closely related to the administration of more than two nephrotoxic drugs combined with aerosolized colistin (OR = 15.03, 95% CI 1.40-161.76; p = 0.025) and septic shock (OR = 8.10, 95% CI 1.40-161.76; p = 0.04). CONCLUSIONS: The use of adjunctive aerosolized colistin treatment appears to be a relatively safe and effective option for the treatment of VAP caused by MDR-GNB. However, more research on the concomitant use of nephrotoxic drugs with aerosolized colistin will be necessary, as this can be an important risk factor of development of AKI.

Endobronchial Neurilemmoma Mimicking a Bronchial Polyp

Neurilemmomas are relatively uncommon, slowly growing tumors which originate from Schwann cells. Intrathoracic neurilemmomas often occur in the chest wall and posterior mediastinum, but endobronchial neurilemmomas are exceedingly rare. These tumors in trachea or bronchus are usually detected by radiologic examinations, mostly computed tomography scan of chest. An 88-year-old man was admitted for management of pneumonia in left lower lobe and parapneumonic effusion. On bronchoscopic examination, there was a small polypoid nodule less than 1 cm in diameter mimicking an endobronchial inflammatory polyp at the bifurcation of the right anterior segmental bronchus and lateral segmental bronchus and under auto-fluorescence imaging, the nodule showed reddish brown area with defined margin. The bronchoscopic biopsy revealed that the bronchial nodule was endobronchial neurilemmoma. This is an interesting case of endobronchial neurilemmoma mimicking a bronchial polyp that is detected incidentally via bronchoscopy.

Bacillus Calmette-Guerin Suppresses Asthmatic Responses via CD4+CD25+ Regulatory T Cells and Dendritic Cells

PURPOSE: Bacillus Calmette-Guerin (BCG) is known to suppress the asthmatic responses in a murine model of asthma and to induce dendritic cells (DCs) maturation. Mature DCs play a crucial role in the differentiation of regulatory T cells (Tregs), which are known to regulate allergic inflammatory responses. To investigate whether BCG regulates Tregs in a DCs-mediated manner, we analyzed in a murine model of asthma. METHODS: BALB/c mice were injected intraperitoneally with BCG or intravenously with BCG-stimulated DCs and then sensitized and challenged with ovalbumin (OVA). Mice were analysed for bronchial hyperresponsiveness (BHR), the influx of inflammatory cells in the bronchoalveolar lavage (BAL) fluid, and histopathological changes in the lung. To identify the mechanisms, IgE, IgG1 and IgG2a in the serum were analysed and the CD25+ Tregs in the mice were depleted with anti-CD25 monoclonal antibody (mAb). RESULTS: BCG and the transfer of BCG-stimulated DCs both suppressed all aspects of the asthmatic responses, namely, BHR, the production of total IgE and OVA-specific IgE and IgGs, and pulmonary eosinophilic inflammation. Anti-CD25mAb treatment reversed these effects. CONCLUSIONS: BCG can attenuate the allergic inflammation in a mouse model of asthma by a Tregs-related mechanism that is mediated by DCs.

A Novel Synthetic Mycolic Acid Inhibits Bronchial Hyperresponsiveness and Allergic Inflammation in a Mouse Model of Asthma

PURPOSE: Recognition of microbes is important to trigger the innate immune system. Mycolic acid (MA) is a component of the cell walls of mycobacteria such as Mycobacterium bovis Bacillus Calmette-Guerin. MA has immunogenic properties, which may modulate the innate and adaptive immune response. This study aimed to investigate whether a novel synthetic MA (sMA) inhibits allergic inflammatory responses in a mouse model of asthma. METHODS: BALB/c mice were injected intraperitoneally with sMA followed by sensitization and challenge with ovalbumin (OVA). Mice were examined for bronchial hyperresponsiveness (BHR), the influx of inflammatory cells into the lung tissues, histopathological changes in the lungs and CD4+CD25+Foxp3+ T cells in the spleen, and examined the response after the depleting regulatory T cells (Tregs) with an anti-CD25mAb. RESULTS: Treatment of mice with sMA suppressed the asthmatic response, including BHR, bronchoalveolar inflammation, and pulmonary eosinophilic inflammation. Anti-CD25mAb treatment abrogated the suppressive effects of sMA in this mouse model of asthma and totally depleted CD4+CD25+Foxp3+ T cells in the spleen. CONCLUSIONS: sMA attenuated allergic inflammation in a mouse model of asthma, which might be related with CD4+CD25+Foxp3+ T cell.

Prevalence of Chronic Obstructive Pulmonary Disease in Korea: The Result of Forth Korean National Health and Nutrition Examination Survey / 결핵및호흡기질환

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major cause of chronic morbidity and mortality throughout the world and is the only major disease that is continuing to increase in both prevalence and mortality. The second Korean National Health and Nutrition Survey revealed that the prevalence of COPD in Korean subjects aged > or =45 years was 17.2% in 2001. Further surveys on the prevalence of COPD were not available until 2007. Here, we report the prevalence of spirometrically detected COPD in Korea, using data from the fourth Korean National Health and Nutrition Survey (KNHANES IV) which was conducted in 2007~2009. METHODS: Based on the Korean Statistical Office census that used nationwide stratified random sampling, 10,523 subjects aged > or =40 years underwent spirometry. Place of residence, levels of education, income, and smoking status, as well as other results from a COPD survey questionnaire were also assessed. RESULTS: The prevalence of COPD (defined as forced expiratory volume in 1 sec/forced vital capacity or =40 years) was 12.9% (men, 18.7%; women, 7.5%). In total, 96.5% of patients with COPD had mild-to-moderate disease; only 2.5% had been diagnosed by physicians, and only 1.7% had been treated. The independent risk factors for COPD were smoking, advanced age, and male gender. CONCLUSION: The prevalence of COPD was 12.9% in the KNHANES IV data. Most patients with COPD were undiagnosed and untreated. Based on these results, a strategy for early COPD intervention is warranted in high risk subjects.

Vancomycin-Resistant Enterococcus faecium Meningitis Treated with Linezolid: A Case Report and Review of the Literature / 감염과화학요법

Vancomycin-resistant enterococci (VRE) infection is a serious problem because optimal therapy has not been established. Different agents in various combinations, including teicoplanin, chloramphenicol, and quinupristin/dalfopristin, have been used to treat patients with VRE meningitis, but the efficacy of these agents is not satisfactory because of their limited ability to penetrate into the cerebrospinal fluid. We report a case of nosocomial vancomycin-resistant Enterococcus faecium meningitis in a patient with ventriculoperitoneal shunt that was successfully treated with linezolid. We will also review previously reported cases of vancomycin-resistant E. faecium meningitis treated by linezolid.

Utility of Micro CT in a Murine Model of Bleomycin-Induced Lung Fibrosis / 결핵및호흡기질환

BACKGROUND: Micro computed tomography (CT) is rapidly developing as an imaging tool, especially for mice, which have become the experimental animal of choice for many pulmonary disease studies. We evaluated the usefulness of micro CT for evaluating lung fibrosis in the murine model of bleomycin-induced lung inflammation and fibrosis. METHODS: The control mice (n=10) were treated with saline. The murine model of lung fibrosis (n=60) was established by administering bleomycin intra-tracheally. Among the 70 mice, only 20 mice had successful imaging analyses. We analyzed the micro CT and pathological findings and examined the correlation between imaging scoring in micro CT and histological scoring of pulmonary inflammation or fibrosis. RESULTS: The control group showed normal findings on micro CT. The abnormal findings on micro CT performed at 3 weeks after the administration of bleomycin were ground-glass opacity (GGO) and consolidation. At 6 weeks after bleomycin administration, micro CT showed various patterns such as GGO, consolidation, bronchiectasis, small nodules, and reticular opacity. GGO (r=0.84) and consolidation (r=0.69) on micro CT were significantly correlated with histological scoring that reflected pulmonary inflammation (p<0.05). In addition, bronchiectasis (r=0.63) and reticular opacity (r=0.83) on micro CT shown at 6 weeks after bleomycin administration correlated with histological scoring that reflected lung fibrosis (p<0.05). CONCLUSION: These results suggest that micro CT findings from a murine model of bleomycin-induced lung fibrosis reflect pathologic findings, and micro CT may be useful for predicting bleomycin-induced lung inflammation and fibrosis in mice.

Utility of Micro CT in a Murine Model of Bleomycin-Induced Lung Fibrosis / 결핵및호흡기질환

BACKGROUND: Micro computed tomography (CT) is rapidly developing as an imaging tool, especially for mice, which have become the experimental animal of choice for many pulmonary disease studies. We evaluated the usefulness of micro CT for evaluating lung fibrosis in the murine model of bleomycin-induced lung inflammation and fibrosis. METHODS: The control mice (n=10) were treated with saline. The murine model of lung fibrosis (n=60) was established by administering bleomycin intra-tracheally. Among the 70 mice, only 20 mice had successful imaging analyses. We analyzed the micro CT and pathological findings and examined the correlation between imaging scoring in micro CT and histological scoring of pulmonary inflammation or fibrosis. RESULTS: The control group showed normal findings on micro CT. The abnormal findings on micro CT performed at 3 weeks after the administration of bleomycin were ground-glass opacity (GGO) and consolidation. At 6 weeks after bleomycin administration, micro CT showed various patterns such as GGO, consolidation, bronchiectasis, small nodules, and reticular opacity. GGO (r=0.84) and consolidation (r=0.69) on micro CT were significantly correlated with histological scoring that reflected pulmonary inflammation (p<0.05). In addition, bronchiectasis (r=0.63) and reticular opacity (r=0.83) on micro CT shown at 6 weeks after bleomycin administration correlated with histological scoring that reflected lung fibrosis (p<0.05). CONCLUSION: These results suggest that micro CT findings from a murine model of bleomycin-induced lung fibrosis reflect pathologic findings, and micro CT may be useful for predicting bleomycin-induced lung inflammation and fibrosis in mice.

Comparison for the Effects of Triple Therapy with Salmeterol/Fluticasone Propionate and Tiotropium Bromide versus Individual Components in Patients of Severe COPD Combined with Bronchial Hyperresponsiveness / 결핵및호흡기질환

BACKGROUND: A combination of salmeterol and fluticasone propionate (SFC) and tiotropium bromide (TIO) is commonly prescribed for COPD patients but there is little data on their effectiveness, particularly in COPD patients with bronchial hyperresponsiveness. This study compared the spirometric improvement based on the change in FEV1, FEV1/FVC, and IC as well as the clinical outcomes of the therapeutic strategies with SFC and TIO versus the individual components in patients with severe COPD and bronchial hyperresponsiveness. METHODS: This study examined the spirometric data and clinical outcomes of 214 patients with COPD and hyperresponsiveness, who were divided into three groups according to the therapeutic regimen (TIO only, SFC only, and a triple therapy regimen). RESULTS: All regimen groups showed early improvement in the FEV1 and IC (at 3- and 6 months after treatment). However, long-term beneficial effects were observed only in the SFC group (at 24 months after treatment). However, these beneficial effects decreased after a 36-month follow up. In all spirometric results, the 12-, 24-, and 36-months data showed a similar degree of improvement in the three groups. The triple therapy group showed higher St. George's Respiratory Questionnaire scores and lower acute exacerbations and hospitalization. CONCLUSION: SFC can be a more important component in the pharmacological treatment of severe COPD patients with hyperresponsiveness than TIO, particularly in the spirometric and clinical outcomes.

The clinical characteristics of non-resolving or slow-resolving pneumonia associated with the pathology of an organizing pneumonia / 대한내과학회지

BACKGROUND/AIMS: Non-resolving or slow-resolving pneumonia refers to the persistence of pulmonary infiltrates for >30 days after an initial pneumonia-like illness. Organizing pneumonia (OP) can be found on a lung biopsy in association with a number of diseases. The object of this study was to elucidate the clinical characteristics of the non-resolving pneumonia with the pathology of an OP and suggest the proper diagnostic and therapeutic approaches for the reduction of unnecessary procedures. METHODS: We retrospectively analyzed 70 patients diagnosed with an OP by percutaneous transthoracic needle biopsy and that met the inclusion criteria. Their pulmonary lesions were reviewed for disease resolution. Patients were divided into either a radiologically benign group (group I, n=57) or a malignancy group (group II, n=13) based on the computed tomography (CT) findings. RESULTS: All patients in group I and 8 patients in group II improved and had a complete resolution by 81.70+/-45.36 days. The microbiology findings showed that many infectious pathogens can lead to an OP despite antibiotic therapy. Three cases in group II were ultimately diagnosed as malignancies. CONCLUSIONS: Our data suggest that non-resolving or slow-resolving lesions were strongly suspicious for a malignancy on the CT scans, despite appearing to be benign OP pathologically; such cases should be considered for re-biopsy. In cased with pathology consistent with OP and benign CT findings, careful observation for 3 months is recommended to allow for the complete radiological resolution of the benign OP associated with infection.

Elevated C-reactive Protein Levels are a Sign of Pulmonary Arterial Hypertension in AECOPD / 결핵및호흡기질환

BACKGROUND: In chronic obstructive pulmonary disease (COPD) patients, the serum levels of C-reactive protein (CRP) are elevated and an increase of CRP is more exaggerated in the acute exacerbation form of COPD (AECOPD) than in stable COPD. Pulmonary arterial hypertension is a common complication of COPD. An increased level of CRP is known to be associated with the risk of systemic cardio-vascular disorders. However, few findings are available on the potential role of CRP in pulmonary arterial hypertension due to COPD. METHODS: This study was performed prospectively and the study population was composed of 72 patients that were hospitalized due to AECOPD. After receiving acute management for AECOPD, serum CRP levels were evaluated, arterial oxygen pressure (PaO2), was measured, and the existence of pulmonary arterial hypertension under room air inhalation was determined in the patients. RESULTS: The number of patients with pulmonary arterial hypertension was 47 (65.3%)., There was an increased prevalence of pulmonary arterial hypertension and an increase of serum CRP levels in patients with the higher stages of COPD (e.g., patients with stage 3 and stage 4 disease; P<0.05). The mean serum CRP levels of patients with pulmonary arterial hypertension and without pulmonary arterial hypertension were 37.6+/-7.4 mg/L and 19.9 +/-6.6 mg/L, respectively (P<0.05). However, there was no significant difference of the mean values of PaO2 between patients with pulmonary arterial hypertension and without pulmonary arterial hypertension statistically (77.8+/-3.6 mmHg versus 87.2+/-6.0 mmHg). CONCLUSION: We conclude that higher serum levels of CRP can be a sign for pulmonary arterial hypertension in AECOPD patients.

Angiopoietin-1 variant, COMP-Ang1 attenuates hydrogen peroxide-induced acute lung injury

Reactive oxygen species (ROS) play a crucial role in acute lung injury. Tissue inflammation, the increased vascular permeability, and plasma exudation are cardinal features of acute lung injury. Angiopoietin-1 (Ang1) has potential therapeutic applications in preventing vascular leakage and also has beneficial effects in several inflammatory disorders. Recently developed COMP-Ang1 is more potent than native Ang1 in phosphorylating tyrosine kinase with immunoglobulin and EGF homology domain 2 receptor in endothelial cells. However, there are no data on effects and related molecular mechanisms of COMP- Ang1 on ROS-induced acute lung injury. We used hydrogen peroxide (H2O2)-inhaled mice to evaluate the effect of COMP-Ang1 on pulmonary inflammation, bronchial hyper-responsiveness, and vascular leakage in acute lung injury. The results have revealed that VEGF expression, the levels of IL-4, TNF-alpha, IL-1 beta, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 in lungs, the levels of hypoxia-inducible factor-1alpha (HIF-1 alpha) and NF-kappa B in nuclear protein extracts, phosphorylation of Akt, and vascular permeability were increased after inhalation of H2O2 and that the administration of COMP-Ang1 markedly reduced airway hyper-responsiveness, pulmonary inflammation, plasma extravasation, and the increases of cytokines, adhesion molecules, and VEGF in lungs treated with H2O2. We have also found that the activation of HIF-1a and NF-kappa B and the increase of phosphoinositide 3-kinase activity in lung tissues after H2O2 inhalation were decreased by the administration of COMP-Ang1. These results suggest that COMP-Ang1 ameliorates ROS-induced acute lung injury through attenuating vascular leakage and modulating inflammatory mediators.

Clear Cell "Sugar" Tumor of the Lung: A Well-Enhanced Mass with an Early Washout Pattern on Dynamic Contrast-Enhanced Computed Tomography

Clear cell tumor of the lung is a rare and very unusual benign pulmonary tumor. As clear cell tumor of the lung contains abundant cytoplasmic glycogen, this tumor is called "sugar tumor". We report a case of sugar tumor in a 64-yr-old man presenting as a round pulmonary nodule. On dynamic computed tomography (CT) scans, the solitary pulmonary nodule showed early wash-in enhancement with an early washout pattern like a lung malignancy. The patient underwent wedge resection for the tumor. Pathologic examination, including immunohistochemical studies, revealed that the nodule was a benign clear cell tumor, so-called "sugar tumor". Because only a small number of cases have been reported previously, clinical aspects, radiological characteristics on dynamic contrast-enhanced CT, and differential diagnosis of the tumor are not well established. Herein we present a clear cell tumor of the lung and discuss the clinical, radiological, and pathological features of the tumor.

Use of Tadalafil for Treating Pulmonary Arterial Hypertension Secondary to Chronic Obstructive Pulmonary Disease

Pulmonary arterial hypertension (PAH) secondary to chronic obstructive pulmonary disease (COPD) is incurable and it has an unpredictable survival rate. Two men who suffered from COPD presented with progressive dyspnea and edema, respectively. PAH, as estimated by the peak velocity of tricuspidal regurgitation, and the depressed myocardial performance index (MPI) of the right ventricle (RV) were noted on echocardiography. In addition to the baseline therapy for their depressed ventilatory function, we prescribed tadalafil 10 mg orally every other day for 2 weeks and then we doubled the dosage. They well tolerated the medication without any notable side effects. After 4 weeks of tadalafil treatment, the patients' pulmonary arterial pressure was decreased and the MPI of the RV was improved in both. The exercise capacity, as measured by the respiratory oxygen uptake, also improved from 10.9 mL/kg/min to 13.8 mL/kg/min in one patient. We report here on 2 patients with PAH secondary to COPD, and they showed notable improvement of their pulmonary hemodynamics and exercise capacity with the administration of tadalafil.