Endobronchial valves for emphysema and persistent air-leak: 10-year experience in an Asian country.

BACKGROUND: Endobronchial valve (EBV) therapy, a validated method for bronchoscopic lung volume reduction (BLVR) in severe emphysema, has been explored for persistent air-leak (PAL) management. However, its effectiveness and safety in the Asian population require further real-world evaluation. In this study, we assessed the outcomes of treatment with EBV within this demographic. METHODS: We conducted a retrospective analysis of medical records from 11 Korean centers. For the emphysema cohort, inclusion criteria were patients diagnosed with emphysema who underwent bronchoscopy intended for BLVR. We assessed these patients for clinical outcomes of chronic obstructive pulmonary disease. All patients with PAL who underwent treatment with EBV were included. We identified the underlying causes of PAL and evaluated clinical outcomes after the procedure. RESULTS: The severe emphysema cohort comprised 192 patients with an average age of 70.3 years, and 95.8% of them were men. Ultimately, 137 underwent treatment with EBV. Three months after the procedure, the BLVR group demonstrated a significant improvement in forced expiratory volume in 1 s (+160 mL vs. +30 mL; P = 0.009). Radiographic evidence of lung volume reduction 6 months after BLVR was significantly associated with improved survival (adjusted hazard ratio 0.020; 95% confidence interval 0.038-0.650; P = 0.010). Although pneumothorax was more common in the BLVR group (18.9% vs. 3.8%; P = 0.018), death was higher in the no-BLVR group (38.5% vs. 54.5%, P = 0.001), whereas other adverse events were comparable between the groups. Within the subset of 18 patients with PAL, the predominant causes of air-leak included spontaneous secondary pneumothorax (44.0%), parapneumonic effusion/empyema (22.2%), and post-lung resection surgery (16.7%). Following the treatment, the majority (77.8%) successfully had their chest tubes removed. Post-procedural complications were minimal, with two incidences of hemoptysis and one of empyema, all of which were effectively managed. CONCLUSIONS: Treatment with EBV provides substantial clinical benefits in the management of emphysema and PAL in the Asian population, suggesting a favorable outcome for this therapeutic approach.

Trends and an Online Survey on the Use of Rigid Bronchoscopy in Korea.

BACKGROUND: Although almost all interventional pulmonologists agree that rigid bronchoscopy is irreplaceable in the field of interventional pulmonology, less is known about the types of diseases that the procedure is used for and what difficulties the operators face during the procedure. The purpose of this study is to evaluate what diseases rigid bronchoscopy is used for, whether it is widely used, and what challenges the operators face in Korea. METHODS: We enrolled 14 hospitals in this retrospective cohort of patients who underwent rigid bronchoscopy between 2003 and 2020. An online survey was conducted with 14 operators to investigate the difficulties associated with the procedure. RESULTS: While the number of new patients at Samsung Medical Center (SMC) increased from 189 in 2003-2005 to 468 in 2018-2020, that of other institutions increased from 0 to 238. The proportion of SMC patients in the total started at 100% and steadily decreased to 59.2%. The proportion of malignancy as the indication for the procedure steadily increased from 29.1% to 43.0%, whereas post-tuberculous stenosis (25.4% to 12.9%) and post-intubation stenosis (19.0% to 10.9%) steadily decreased (all P for trends < 0.001). In the online survey, half of the respondents stated that over the past year they performed less than one procedure per month. The fewer the procedures performed within the last year, the more likely collaboration with other departments was viewed as a recent obstacle (Spearman correlation coefficient, rs = -0.740, P = 0.003) and recent administrative difficulties were encountered (rs = -0.616, P = 0.019). CONCLUSION: This study demonstrated that the number of patients undergoing rigid bronchoscopy has been increasing, especially among cancer patients. For this procedure to be used more widely, it will be important for beginners to systematically learn about the procedure itself as well as to achieve multidisciplinary consultation.

Prevalence of Respiratory Viral Infections in Korean Adult Asthmatics With Acute Exacerbations: Comparison With Those With Stable State.

PURPOSE: Viral infections are involved in ~50% of exacerbations among Caucasian adult asthmatics. However, there have been few reports on the causative virus of exacerbations in Korean adult asthmatics. Thus, we compared frequencies and types of viruses between lower respiratory tract illnesses (LRTIs) with exacerbations (exacerbated LRTIs) and those without exacerbations (stable LRTIs) to evaluate contribution of respiratory viruses to exacerbations. METHODS: Viral RNA was extracted from sputum using the Viral Gene-spin™ Kit. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect adenovirus (ADV), metapneumovirus (MPV), parainfluenza virus (PIV) 1/2/3, influenza virus (IFV) A, IFV B, respiratory syncytial virus (RSV) A/B, and rhinovirus (RV) A. RESULTS: Among the 259 patients, 210 underwent a single sputum examination, and the remaining 49 underwent 2 to 4 sputum examinations. Virus was detected in 68 of the 259 exacerbated episodes and in 11 of the 64 stable episodes. Among the exacerbated episodes, RV was the most frequently detected virus, followed by influenza A, parainfluenza, RSV A/B, and ADV. Among the 11 stable episodes, RV was most frequently detected. Detection rates of these viruses did not differ between the 2 groups (P>0.05). Thirty-five patients underwent the virus examination at 2 episodes of exacerbation, while 14 patients underwent at each time of exacerbated and stable episodes. Virus detection rate at the second examination was significantly higher in cases with 2 exacerbation episodes than in those with initial exacerbation and sequential stable episodes (P=0.003). A seasonal pattern was noted in the detection rates of RV (September to December), IFV (January to April), PIV (May to September), and RSV A/B (September to April). CONCLUSIONS: Respiratory viruses were identified in approximately 20% of LRTI irrespective of the presence of asthma exacerbation. RV and IFV A/B were most frequently detected. A group of patients experienced frequent viral infections followed by asthma exacerbations.

Upregulation of interleukin-33 and thymic stromal lymphopoietin levels in the lungs of idiopathic pulmonary fibrosis.

BACKGROUND: Innate T helper type 2 (Th2) immune responses mediated by interleukin (IL)-33, thymic stromal lymphopoietin (TSLP), and IL-25 have been shown to play an important role in pulmonary fibrosis of animal models; however, their clinical implications remain poorly understood. METHODS: TSLP, IL-25, and IL-33 concentrations were measured in bronchoalveolar lavage fluids obtained from normal controls (NCs; n = 40) and from patients with idiopathic pulmonary fibrosis (IPF; n = 100), non-specific interstitial pneumonia (NSIP; n = 22), hypersensitivity pneumonitis (HP; n = 20), and sarcoidosis (n = 19). RESULTS: The TSLP and IL-33 levels were significantly higher in patients with IPF relative to the NCs (p = 0.01 and p = 0.0001, respectively), NSIP (p = 4.95E - 7 and p = 0.0002, respectively), HP (p = 0.00003 and p = 0.000005, respectively), and sarcoidosis groups (p = 0.003 and p = 0.0001, respectively). However, the IL-25 levels were not significantly different between NC and IPF group (p = 0.432). Receiver operating characteristic curves of the TSLP and IL-33 levels revealed clear differences between the IPF and NC groups (AUC = 0.655 and 0.706, respectively), as well as between the IPF and the other lung disease groups (AUC = 0.786 and 0.781, respectively). Cut-off values of 3.52 pg/µg TSLP and 3.77 pg/µg IL-33 were shown to differentiate between the IPF and NC groups with 99.2 and 94.3% accuracy. Cut-off values of 4.66 pg/µg TSLP and 2.52 pg/µg IL-33 possessed 99.4 and 93.2% accuracy for differentiating among the IPF and other interstitial lung disease groups. CONCLUSIONS: Innate immune responses may be associated with the development of IPF. Furthermore, the IL-33 and TSLP levels in BAL fluids may be useful for differentiating IPF from other chronic interstitial lung diseases.

The role of 18F-fluorodeoxyglucose uptake of bone marrow on PET/CT in predicting clinical outcomes in non-small cell lung cancer patients treated with chemoradiotherapy.

OBJECTIVES: This study aimed to assess the relationship between bone marrow (BM) FDG uptake on PET/CT and serum inflammatory markers and to evaluate the prognostic value of BM FDG uptake for predicting clinical outcomes in non-small cell lung cancer (NSCLC) patients. METHODS: One hundred and six NSCLC patients who underwent FDG PET/CT for staging work-up and received chemoradiotherapy were enrolled. Mean BM FDG uptake (BM SUV) and BM-to-liver uptake ratio (BLR) were measured, along with volumetric parameters of PET/CT. The relationship of BM SUV and BLR with hematologic parameters and serum inflammatory markers was evaluated. Prognostic values of BM SUV and BLR for predicting progression-free survival (PFS) and overall survival (OS) were assessed. RESULTS: BM SUV and BLR were significantly correlated with white blood cell count and C-reactive protein level. On univariate analysis, BLR was a significant prognostic factor for both PFS and OS. On multivariate analysis, TNM stage and BLR were independent prognostic factors for PFS, and only TNM stage was an independent prognostic factor for OS. CONCLUSIONS: In NSCLC patients, FDG uptake of BM reflects the systemic inflammatory response and can be used as a biomarker to identify patients with poor prognosis. KEY POINTS: • Bone marrow FDG uptake is correlated with serum inflammatory markers. • Bone marrow FDG uptake is an independent prognostic factor for progression-free survival. • Bone marrow FDG uptake can provide information on predicting lung cancer progression.

Microorganisms Causing Community-Acquired Acute Bronchitis: The Role of Bacterial Infection.

BACKGROUND: Although acute bronchitis is quite common, there is relatively limited information regarding the microorganisms that are involved in this illness. METHODS: We performed a prospective study of acute bronchitis at 31 hospitals and clinics in Korea from July 2011 to June 2012. Sputum specimens were collected for polymerase chain reaction (PCR) and culture of microorganisms. RESULTS: Of the 811 enrolled patients, 291 had acceptable sputum specimens that were included for analysis of the etiologic distribution. With multiplex PCR testing, viruses were identified in 36.1% (105/291), most commonly rhinovirus (25.8%) and coronavirus (3.8%). Typical bacteria were isolated in 126/291 (43.3%) patients. Among these patients Haemophilus influenzae (n = 39) and Streptococcus pneumoniae (n = 30) were isolated most commonly; atypical bacteria were identified in 44 (15.1%) patients. Bacteria-only, virus-only, and mixed infections (bacteria plus virus) accounted for 36.7% (98/291), 17.2% (50/291), and 18.9% (55/291) of infections, respectively. In particular, 52.4% of patients with viral infection had a concurrent bacterial infection, and rhinovirus was the most common virus in mixed infections (40/55). Additionally, infections with typical bacteria were more common in patients with chronic lung disease (p = 0.029), and typical bacterial infections showed a trend towards a higher prevalence with older age (p = 0.001). CONCLUSIONS: Bacteria were associated with almost half of community-acquired acute bronchitis cases. Additional studies are required to further illuminate the role of bacteria and to identify patient groups most likely to benefit from antibiotic treatment.

Association study of polymorphisms in interferon-γ receptor genes with the risk of pulmonary tuberculosis.

Tuberculosis (TB) is an infectious disease caused by mycobacterium, which most commonly affects the lungs. The adaptive immune response in Mycobacterium tuberculosis is predominantly mediated by the interferon-γ (IFN-γ) signaling pathway, which is regulated by IFN-γ receptors (IFNGR). IFN-γ activates the transcription of a number of genes that are important in immune responses, thus the appropriate function of IFNGR appears to be important in host defense against mycobacteria. In the present study, 22 genetic variants in IFNGR1 and IFNGR2 were genotyped in 673 patients and 592 normal controls to investigate the association between IFNGR1 and IFNGR2 polymorphisms and the risk of TB. Statistical analyses revealed that four genetic variants in IFNGR1, rs9376269, rs9376268, rs9376267 and rs56251346 were marginally associated with the risk of TB (P = 0.02-0.04), while other single nucleotide polymorphisms in IFNGR1 and IFNGR2 did not exhibit any associations. However, the significance of the four genetic variants rs9376269, rs9376268, rs9376267 and rs56251346 was eliminated following a multiple testing correction of the data (P>0.05). The present results revealed that certain genetic variants in IFNGR genes may be associated with TB development, which may be useful preliminary data for future investigation.

Invasive pulmonary mucormycosis with concomitant lung cancer presented with massive hemoptysis by huge pseudoaneurysm of pulmonary artery.

Pulmonary mucormycosis is a rare opportunistic invasive fungal infection involving the pulmonary vasculature in immunocompromised patients. Pseudoaneurysm of pulmonary artery in mucormycosis is a rare fatal complication after invasion and rupture of a pulmonary artery. We report a patient with diabetes mellitus and incidental lung cancer who developed massive hemoptysis because of a huge pseudoaneurysm of the left pulmonary artery by mucormycosis. Although the patient had been managed by amphotericin B followed by left pneumonectomy for persistent hemoptysis, he died from septic shock and multiorgan failure after surgery. Histologic analysis of a surgical specimen revealed concomitant squamous cell lung cancer.

Epidemiological aspects of pertussis among adults and adolescents in a Korean outpatient setting: a multicenter, PCR-based study.

Epidemiological data of Bordetella pertussis infection among adolescents and adults are limited in Korea. Patients (≥ 11 yr of age) with a bothersome cough for less than 30 days were enrolled during a 1-yr period at 22 hospitals in Korea. Nasopharyngeal swabs were collected for polymerase chain reaction (PCR) and for bacteriologic culture. In total, 490 patients were finally enrolled, and 34 (6.9%) patients tested positive for B. pertussis; cough duration (14.0 days [7.0-21.0 days]) and age distribution were diverse. The incidence was the highest in secondary referral hospitals, compared to primary care clinics or tertiary referral hospitals (24/226 [10.6%] vs. 3/88 [3.4%] vs. 7/176 [4.0%], P = 0.012), and the peak incidence was observed in February and August (15.8% and 15.9%), with no confirmed cases between March and June. In the multivariate analysis, post-tussive vomiting was significantly associated with pertussis (odds ratio, 2.508; 95% confidence interval, 1.146-5.486) and secondary referral hospital showed a borderline significance. In conclusion, using a PCR-based method, 6.9% of adolescent and adult patients with an acute cough illness had pertussis infection in an outpatient setting. However, hospital levels and seasonal trends must be taken into account to develop a better strategy for controlling pertussis.

Association analysis of melanocortin 3 receptor polymorphisms with the risk of pulmonary tuberculosis.

PURPOSE: Melanocortin 3 Receptor (MC3R) is one of the families of seven-transmembrane G-protein-coupled receptors, and a recent study showed that MCR3 promoter polymorphism was significantly associated with the susceptibility of tuberculosis (TB) in South African population. METHODS: We analyzed six MC3R polymorphisms to examine the genetic effects on the risk of pulmonary TB in Korean subjects by using TaqMan assays and case-control analyses. RESULTS: Using statistical analyses, one common promoter polymorphism (MC3R rs11575886 T > C) was found to be associated with an increased risk of pulmonary TB. The frequency of the C-bearing genotype of rs11575886 was higher in pulmonary TB patients than in normal controls (p = 0.03, OR = 1.46) although the significance was not retained after correction. In silico analysis for the difference of transcription binding factor (TF), motif between C and T allele demonstrated that the TF motif and its threshold scores of C allele were lower than those of T allele. CONCLUSIONS: The C allele of rs11575886 could be a risk allele for the pulmonary TB by affecting the binding of TF. Our findings suggest that polymorphisms in MC3R might be one of genetic factors for the risk of pulmonary TB development in Korean subjects.

Genome-wide association study identifies ALLC polymorphisms correlated with FEV1 change by corticosteroid.

OBJECTIVES: Asthma can be suppressed by inhaled corticosteroids (ICS). However, response to ICS shows marked inter-individual variability. This study is aimed to identify the genetic variants associated with the change in the percentage of forced expiratory volume in 1second (%ΔFEV1) following ICS treatment. METHODS: A genome-wide association study was performed in a Korean asthmatic cohort. To further investigate these genetic associations, 11 additional single-nucleotide polymorphisms (SNPs) on the allantoicase (ALLC) gene were selected from the HapMap database and genotyped in the same asthmatic patients in the follow-up study. RESULTS: In a genome-wide study, we identified the lowest P-value in ALLC, but none of the SNPs met the genome-wide association criteria (P<1.0×10(-8)). However, among 25 SNPs on ALLC in the follow-up study, 6 variants showed significant associations with the mean %ΔFEV1 in the study subjects (P<3.73×10(-6)). CONCLUSIONS: Although the associated signals could not overcome the genome-wide multiple correction due to small sample size (n=189), our results suggest that associated SNPs of ALLC might be genetic predictors of response to ICS, at least with respect to ΔFEV1 in Korean asthmatics.

Risk factors influencing rebleeding after bronchial artery embolization on the management of hemoptysis associated with pulmonary tuberculosis.

BACKGROUND: Hemoptysis due to pulmonary tuberculosis (TB) frequently develops in Korea where the prevalence of TB is intermediate. The effect of bronchial artery embolization (BAE) on the control of massive hemoptysis has been well known. This study is designed to identify the risk factors contributing to rebleeding after BAE in patients with TB. METHODS: We retrospectively evaluated risk factors and the time for rebleeding after BAE in 72 patients presenting with hemoptysis. RESULTS: The overall immediate success rate of BAE was 93.1% (67 of 72 patients). Of the 29 patients (40.3%) who showed rebleeding after BAE, 13 patients experienced rebleeding within 1 month, and 14 patients between 1 month to 1 year. The existence of a shunt in angiographic finding, aspergilloma, and diabetes mellitus were risk factors of rebleeding after BAE in multivariate analysis. CONCLUSION: BAE was very effective for obtaining immediate bleeding control in hemoptysis associated with active TB or post-TB sequelae. It is important to observe whether or not rebleeding occurs up to 1 year of BAE especially in TB patients with aspergilloma, DM, or a shunt. Even rebleeding can be managed well by second BAE.

A Multicenter Study of Pertussis Infection in Adults with Coughing in Korea: PCR-Based Study.

BACKGROUND: Limited data on the incidence and clinical characteristics of adult pertussis infections are available in Korea. METHODS: Thirty-one hospitals and the Korean Centers for Disease Control and Prevention collaborated to investigate the incidence and clinical characteristics of pertussis infections among adults with a bothersome cough in non-outbreak, ordinary outpatient settings. Nasopharyngeal aspirates or nasopharyngeal swabs were collected for polymerase chain reaction (PCR) and culture tests. RESULTS: The study enrolled 934 patients between September 2009 and April 2011. Five patients were diagnosed as confirmed cases, satisfying both clinical and laboratory criteria (five positive PCR and one concurrent positive culture). Among 607 patients with cough duration of at least 2 weeks, 504 satisfied the clinical criteria of the US Centers for Disease Control and Prevention (i.e., probable case). The clinical pertussis cases (i.e., both probable and confirmed cases) had a wide age distribution (45.7±15.5 years) and cough duration (median, 30 days; interquartile range, 18.0~50.0 days). In addition, sputum, rhinorrhea, and myalgia were less common and dyspnea was more common in the clinical cases, compared to the others (p=0.037, p=0.006, p=0.005, and p=0.030, respectively). CONCLUSION: The positive rate of pertussis infection may be low in non-outbreak, ordinary clinical settings if a PCR-based method is used. However, further prospective, well-designed, multicenter studies are needed.

The effect of post-treatment N-acetylcysteine in LPS-induced acute lung injury of rats.

BACKGROUND: Oxidation plays an important role in acute lung injury. This study was conducted in order to elucidate the effect of repetitive post-treatment of N-acetylcysteine (NAC) in lipopolysaccaride (LPS)-induced acute lung injury (ALI) of rats. METHODS: Six-week-old male Sprague-Dawley rats were divided into 4 groups. LPS (Escherichia coli 5 mg/kg) was administered intravenously via the tail vein. NAC (20 mg/kg) was injected intraperitoneally 3, 6, and 12 hours after LPS injection. Broncho-alveolar lavage fluid (BALF) and lung tissues were obtained to evaluate the ALI at 24 hours after LPS injection. The concentration of tumor necrosis factor α (TNF-α) and interleukin 1ß (IL-1ß) were measured in BALF. Nuclear factor κB (NF-κB), lipid peroxidation (LPO), and myeloperoxidase (MPO) were measured using lung tissues. Micro-computed tomography (micro-CT) images were examined in each group at 72 hours apart from the main experiments in order to observe the delayed effects of NAC. RESULTS: TNF-α and IL-1ß concentration in BALF were not different between LPS and NAC treatment groups. The concentration of LPO in NAC treatment group was significantly lower than that of LPS group (5.5±2.8 nmol/mL vs. 16.5±1.6 nmol/mL) (p=0.001). The activity of MPO in NAC treatment group was significantly lower than that of LPS group (6.4±1.8 unit/g vs. 11.2±6.3 unit/g, tissue) (p<0.048). The concentration of NF-κB in NAC treatment group was significantly lower than that of LPS group (0.3±0.1 ng/µL vs. 0.4±0.2 ng/µL) (p=0.0001). Micro-CT showed less extent of lung injury in NAC treatment than LPS group. CONCLUSION: After induction of ALI with lipopolysaccharide, the therapeutic administration of NAC partially attenuated the extent of ALI through the inhibition of NF-κB activation.

Remarkable Effect of Gefitinib Retreatment in a Lung Cancer Patient With Lepidic Predominat Adenocarcinoma who had Experienced Favorable Results From Initial Treatment With Gefitinib: A Case Report.

Gefitnib is an oral agent of epidermal growth factor receptor tyrosine kinase inhibitor, and it has a certain efficacy against non-small cell lung cancer. There are some reports that the non-small cell lung cancer patients who experienced disease progression after responding to gefitinib were again sensitive to re-administration of gefitinib following temporary cessation of gefitinib. This is the case report showing a remarkable effect of gefitinib re-treatment in a patient with metastatic invasive adenocarinoma who had experienced favorable results from the initial treatment with gefitinib.

Catamenial hemoptysis: a nationwide analysis in Korea.

BACKGROUND: Hemoptysis is a potentially serious clinical problem. However, there is no consensus on the clinical characteristics, treatment and patient outcome of catamenial hemoptysis. OBJECTIVE: Clinical characteristics, treatments and outcome in patients of catamenial hemoptysis were evaluated. METHODS: We conducted a retrospective nationwide observational analysis of Korean patients with catamenial hemoptysis. RESULTS: Nineteen patients with catamenial hemoptysis were evaluated from 13 tertiary-care hospitals in Korea. The median age of the patients was 25 years; 8 (42%) were ever-smokers. Eight patients were pathologically diagnosed; 11 were diagnosed by clinical criteria. Sixteen (84%) patients had a history of obstetric or gynecological procedures before developing hemoptysis. The mean amount of hemoptysis (mean +/- SD) was 58.3 +/- 71.3 for surgery, 46.4 +/- 33.2 for hormonal and 29.1 +/- 26.3 for conservative treatment groups. Hemoptysis did not recur in 8 (89%) of 9 patients after surgery. None of the patients in the hormonal or conservative treatment groups had persistent hemoptysis. There was an excellent outcome (complete remission and partial responses) in all patients with conservative treatment, suggesting that endometrial cells implanted into the lung may have a benign course. CONCLUSION: Patients without massive hemoptysis can be treated conservatively or with hormonal agents.

Association of serum leptin and adiponectin with obesity in asthmatics.

BACKGROUND: Mounting evidence implicates obesity as a major risk factor for asthma. Leptin and adiponectin produced by fat tissues play a critical role in the regulation of body weight and allergic inflammation. OBJECTIVE: The aim of this study was to evaluate the effects of leptin and adiponectin on development of asthma. METHODS: We measured the leptin and adiponectin in serum from patients with asthma (n = 60) and normal control subjects (n = 30) by enzyme-linked immunosorbent assay. RESULTS: Logarithmic leptin and adiponectin concentration was not different between asthmatics and control subjects. Although the logarithmic adiponectin level was not different by gender in asthmatics, the logarithmic leptin concentration was significantly higher in females than in male asthmatics (2.41 +/- 0.05 ng/mL vs. 2.01 +/- 0.05 ng/mL, p = 0.001). The leptin/adiponectin ratio was also significantly higher in females than in male asthmatics. The leptin/adiponectin ratio was correlated with body mass index (r = 0.210, p = 0.05) in asthmatics. CONCLUSION: Our results suggest that serum leptin and adiponectin may be associated with gender and obesity regardless of development of asthma.

Obesity in aspirin-tolerant and aspirin-intolerant asthmatics.

BACKGROUND AND OBJECTIVE: Obesity is an important factor in the development of asthma. Aspirin hypersensitivity affects 5-10% of asthmatics. The association between obesity and aspirin hypersensitivity in asthma is unclear. This study evaluated the association of BMI and asthma in patients with aspirin-tolerant asthma (ATA) and aspirin-intolerant asthma (AIA). METHODS: Aspirin provocation tests were performed in 667 asthmatic patients and changes in FEV(1) were used to categorize patients as ATA or AIA. The BMI of asthmatics was graded using the percentile BMI of 406 normal controls. RESULTS: Aspirin-induced changes in FEV(1)% ranged from 15% to 68%. Compared with the controls, the ATA group had a higher BMI (24.5 +/- 0.1 vs 23.8 +/- 0.2 kg/m(2), P = 0.001). The AIA group had a lower BMI. The aspirin-induced percentage fall in FEV(1) was inversely correlated with BMI in asthmatic patients (r = -0.094, P = 0.016). BMI was correlated with age and PC20, but not with FEV(1) in asthmatic patients. In a logistic regression adjusted for age, gender, and smoking status, FEV(1) and PC20 were associated with AIA with odds ratios of 0.986 and 0.586, respectively. BMI was associated with AIA with an odds ratio of 0.916. CONCLUSIONS: Aspirin intolerance in asthmatics explains the lesser association with obesity. Obesity is not a risk factor in the development of asthma in patients with AIA.

Clinical implications of the ethane in exhaled breath in patients with acute paraquat intoxication.

STUDY OBJECTIVES: Pulmonary fibrosis due to lipid peroxidation is a major symptom of paraquat intoxication. Ethane in the expired breath (exEth) reflects lipid peroxidation and may be a measure of the damage effected by oxygen radicals in acute lung injury. The purpose of this study was to evaluate the clinical efficacy of exEth as a measure of exposure to paraquat and as an indicator of lung damage. DESIGN: Exposure levels were evaluated by the amount ingested, semiquantitative measurement of urine paraquat levels, and plasma paraquat concentration. End-tidal breath was collected for measurement of ethane 24 h after paraquat ingestion. Renal function and blood gas analyses were conducted on the same day as the breath collection, and the final clinical outcome was defined as either recovery or death. Associations between exEth and paraquat exposure profiles and clinical outcomes were assessed using linear regression models. PATIENTS: Twenty-one patients poisoned by paraquat were selected for the study during 2001 and 2002. RESULTS: exEth could not be used as a predictor of laboratory parameters such as Pa(O2), Pa(CO2), serum creatinine, and lung injury (as graded by high-resolution CT). A logistical analysis revealed that only the amount of paraquat ingested was a significant predictor of fatality (p = 0.021). The strength of the association between exEth and fatality was unaffected by the addition of potential confounders such as age, sex, and time interval and paraquat concentration. CONCLUSION: exEth cannot be used as either an independent predictor of survival or a specific marker of lung injury in patients with acute paraquat poisoning.