Characteristics of pneumonia with negative chest radiography in cases confirmed by computed tomography.

Background: Chest radiography is commonly used for diagnosing community-acquired pneumonia (CAP). Computed tomography (CT) is not routinely recommended for initial assessment of CAP patients but is more sensitive and more specific than chest radiography. Objectives: To investigate characteristics of pneumonia with negative chest radiography in cases confirmed by CT. Methods: We included patients diagnosed with CAP in the emergency department, and chest radiography and CT were performed and sputum cultures were collected. The CR- group was defined as patients for whom infiltration of pneumonia was detected only on CT. The CR+ group was defined as patients for whom infiltration was detected on both chest radiography and CT. Data were collected retrospectively from medical records. Results: A total of 138 patients were included, with 58 patients in the CR- group and 80 patients in the CR+ group. Mean age was higher in the CR- group than in the CR+ group, and white blood cell counts and C-reactive protein (CRP) levels were lower in the CR- group than in the CR+ group (8.4 × 103/µL vs 12.4 × 103/µL, p = 0.01; 4.7 mg/dL vs 15.6 mg/dL, p < 0.001, respectively). Laterality of the infiltrated lungs differed between groups (right:left:bilateral = 14:30:14 vs 48:20:12, p = 0.006). Multivariate logistic analysis identified leukocytosis, elevated CRP levels (odds ratio (OR) 3.57, p = 0.003), laterality (OR 2.16, p = 0.006) as predictors of pneumonia in the CR- group. Conclusion: In pneumonia with negative chest radiography in cases confirmed by CT, milder inflammation and infiltration in the left lung tended to be seen.

IL-9 Blockade Suppresses Silica-induced Lung Inflammation and Fibrosis in Mice.

Recapitulative animal models of idiopathic pulmonary fibrosis (IPF) and related diseases are lacking, which inhibits our ability to fully clarify the pathogenesis of these diseases. Although lung fibrosis in mouse models is often induced by bleomycin, silica-induced lung fibrosis is more sustainable and more progressive. Therefore, in this study, we sought to elucidate the mediator(s) responsible for the pathogenesis of lung fibrosis, through the use of a mouse model of silica-induced lung fibrosis. With a single nasal administration of 16 mg of silica, lung inflammation (assessed by elevated cellular components in the BAL fluids [BALFs]) and lung fibrosis (assessed by lung histology and lung hydroxyproline levels) were induced and sustained for as long as 24 weeks. Of the mediators measured in the BALFs, IL-9 was characteristically elevated gradually, and peaked at 24 weeks after silica administration. Treatment of silica-challenged mice with anti-IL-9-neutralizing antibody inhibited lung fibrosis, as assessed by lung hydroxyproline level, and suppressed the levels of major mediators, including IL-1ß, IL-6, IL-12, CCL2, CXCL1, and TNF-α in BALFs. Moreover, human lung specimens from patients with IPF have shown high expression of IL-9 in alveolar macrophages, CD4-positive cells, and receptors for IL-9 in airway epithelial cells. Collectively, these data suggest that IL-9 plays an important role in the pathogenesis of lung fibrosis in diseases such as IPF.

Relationships among smoking habits, airflow limitations, and metabolic abnormalities in school workers.

BACKGROUND: Chronic obstructive pulmonary disease is caused mainly by habitual smoking and is common among elderly individuals. It involves not only airflow limitation but also metabolic disorders, leading to increased cardiovascular morbidity and mortality. OBJECTIVE: We evaluated relationships among smoking habits, airflow limitation, and metabolic abnormalities. METHODS: Between 2001 and 2008, 15,324 school workers (9700 males, 5624 females; age: ≥ 30 years) underwent medical checkups, including blood tests and spirometry. They also responded to a questionnaire on smoking habits and medical history. RESULTS: Airflow limitation was more prevalent in current smokers than in ex-smokers and never-smokers in men and women. The frequency of hypertriglyceridemia was higher in current smokers in all age groups, and those of low high-density-lipoprotein cholesterolemia and diabetes mellitus were higher in current smokers in age groups ≥ 40 s in men, but not in women. There were significant differences in the frequencies of metabolic abnormalities between subjects with airflow limitations and those without in women, but not in men. Smoking index was an independent factor associated with increased frequencies of hypertriglyceridemia (OR 1.015; 95% CI: 1.012-1.018; p<0.0001) and low high-density-lipoprotein cholesterolemia (1.013; 1.010-1.016; p<0.0001) in men. Length of smoking cessation was an independent factor associated with a decreased frequency of hypertriglyceridemia (0.984; 0.975-0.994; p = 0.007). CONCLUSIONS: Habitual smoking causes high incidences of airflow limitation and metabolic abnormalities. Women, but not men, with airflow limitation had higher frequencies of metabolic abnormalities.

Diagnostic and prognostic value of procalcitonin in community-acquired pneumonia.

INTRODUCTION: The value of measuring procalcitonin (PCT) in patients with community-acquired pneumonia (CAP) is unclear. The aim of this study was to determine the value of PCT as a marker for microbial etiology and a predictor of outcome in CAP patients. METHODS: A single-center observational study was conducted with CAP patients. On admission, their leukocyte count, serum C-reactive protein level, and serum PCT level were determined, and microbiological tests were performed. Patients were classified into 4 groups according to the A-DROP scoring system, which assesses the severity of CAP. RESULTS: A total of 102 patients were enrolled. The pathogen was identified in 60 patients, and 31 patients had streptococcal pneumonia. The PCT levels were significantly higher in those patients with pneumococcal pneumonia than in those patients with other bacterial pneumonias (P < 0.0001). Multivariate regression analysis revealed that high PCT levels were associated with a pneumococcal etiology [odds ratio, 1.68; 95% confidence interval (CI): 1.02-2.81; P = 0.04] after adjustment for disease severity and demographic factors. The PCT levels were correlated with the A-DROP score (r = 0.49; P < 0.0001). The area under the curve for predicting mortality was highest for the A-DROP score (0.97; 95% CI: 0.92-0.99), followed by the area under the curve for PCT (0.82; 95% CI: 0.74-0.89) and C-reactive protein (0.77; 95% CI: 0.67-0.84). CONCLUSIONS: High PCT levels indicate that pneumococcal pneumonia and PCT levels depend on the severity of pneumonia. PCT measurements may provide important diagnostic and prognostic information for patients with CAP.

[Case of sarcoidosis with myelodysplastic syndrome in an elderly woman].

An 85-year-old woman, who had been given a diagnosis of myelodysplastic syndrome with refractory anemia 2 years previously and required blood transfusion once a month, was admitted with complaints of fever, general fatigue, and dry cough. A chest X-ray film showed multiple small nodules in bilateral lung fields which were not observed 1 month previously. Although smear and culture tests for acid-fast bacilli in her bronchoalveolar lavage fluid, urine, and bone marrow aspiration fluid were all negative, miliary tuberculosis was strongly suspected. Antituberculosis drugs were administered, but neither her symptoms nor chest X-ray findings improved. Five months later, right oculomotor nerve palsy, followed by left abducens nerve paralysis occurred. Lumber puncture examination revealed lymphocytosis, and increased protein and ACE levels, suggesting neurosarcoidosis. A transbronchial lung biopsy specimen demonstrated non-caseating epithelioid granulomas. Oral administration of 30 mg/day prednisolone improved her symptoms as well as the chest X-ray findings.

Transduction of phosphatase and tensin homolog deleted on chromosome 10 into eosinophils attenuates survival, chemotaxis, and airway inflammation.

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is part of a complex signaling system that affects a variety of important cell functions. PTEN antagonizes the action of PI3K by dephosphorylating the signaling lipid phosphatidylinositol 3,4,5-triphosphate. In the present study, we used a TAT fusion protein transduction system to elucidate the role of PTEN in eosinophils and airway inflammation. A small region of the HIV TAT protein (YGRKKRRQRRR), a protein transduction domain known to enter mammalian cells efficiently, was fused to the N terminus of PTEN. Flow cytometric analysis of annexin V- and propidium iodide-stained cells was used to assess eosinophil survival. A chemotaxis assay was performed using a Boyden chamber. Cell analysis in bronchoalveolar lavage fluid and histological examinations were performed using OVA-challenged A/J mice. We found that TAT-PTEN was successfully internalized into eosinophils and functioned as a phosphatase in situ. TAT-PTEN, but not a TAT-GFP control protein, blocked the ability of IL-5 to prevent the apoptosis of eosinophils from allergic subjects. The eotaxin-induced eosinophil chemotaxis was inhibited by TAT-PTEN in a dose-dependent manner. Intranasal pretreatment with TAT-PTEN, but not TAT-GFP, significantly inhibited the OVA-induced eosinophil infiltration in bronchoalveolar lavage fluid. Histological examination of the lung, including H&E and Alcian blue/periodic acid-Schiff staining, revealed that TAT-PTEN, but not TAT-GFP, abrogated eosinophilic inflammation and mucus production. Our results suggest that PTEN negatively regulates eosinophil survival, chemotaxis, and allergic inflammation. The pharmacological targeting of PTEN may constitute a new strategy for the treatment of eosinophilic disorders.

Effect of procaterol, a beta(2) selective adrenergic receptor agonist, on airway inflammation and hyperresponsiveness.

BACKGROUND: beta-agonists are frequently used as bronchodilators for asthma as not only a reliever but also a controller, and their utility has increased with the development of long-acting beta(2) selective drugs. Although anti-inflammatory effects of beta(2) selective-agonists have been reported in vitro, side effects on augmentation of airway hyperresponsiveness by chronic use of beta(2) selective-agonists have been described in several reports. In this study, we investigated the effects of procaterol, a second-generation beta(2)-agonist, on airway inflammation in vivo using an antigen-specific murine model of asthma. METHODS: Mice immunized with ovalbumin (OVA) + alum and challenged with inhaled ovalbumin were orally administered procaterol during the challenge. After inhalation, the mice were tracheostomized and placed in a body box under controlled ventilation to measure airway resistance before and after acetylcholine inhalation. RESULTS: Administration of procaterol at a clinical dose equivalent did not augment airway hyperresponsiveness, inflammation of the airway wall, or subsequent airway wall thickening induced by OVA inhalation. BALF cell analysis revealed that the eosinophil number in the BALF was significantly reduced in procaterol-treated mice compared to untreated mice. CONCLUSIONS: Oral administration of procaterol at a clinical dose did not augment airway responsiveness, but did reduce eosinophil inflammation.

The role of platelet-derived growth factor receptor in eotaxin signaling of eosinophils.

BACKGROUND: Receptor tyrosine kinases (RTKs) such as epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor (PDGFR) are capable of eliciting kinase activity after ligand binding. In several cells, RTKs are activated via the G-protein-coupled receptor independent of the ligand-RTK interaction. We have previously found that EGFR is transactivated via CC chemokine receptor 3 in bronchial epithelial cells and that this pathway is important for mitogen-activated protein (MAP) kinase activation and cytokine production. It has recently been suggested that hypereosinophilic syndrome results from the fusion tyrosine kinase FIP1L1-PDGFRA. Although it is possible that the PDGFR signal is involved in eosinophil function, the details are still unclear. METHODS: Blood eosinophils were purified using Percoll and anti-CD16 antibody-coated magnetic beads. Expression of PDGFR mRNA was examined by RT-PCR. After stimulating eosinophils with eotaxin, the phosphorylation of MAP kinases was examined by Western blotting with the antiphosphospecific MAP kinase antibody. The eotaxin-induced eosinophil chemotaxis was studied using Boyden chambers. RESULTS: Eosinophils expressed PDGFRbeta mRNA in 4 out of 8 donors, while PDGFRalpha mRNA was expressed in only 1 donor. Protein expression of PDGFR was also detectable in eosinophils from some donors. AG1295, a specific inhibitor of PDGFR, showed dose-dependent inhibition of eotaxin-induced MAP kinase phosphorylation in the eosinophils expressing PDGFRbeta mRNA. The chemotaxis of these eosinophils was significantly inhibited by AG1295 (n = 3). CONCLUSIONS: Our results suggest that PDGFR modifies the CCR3-MAP kinase signaling pathway and chemotactic response in some donors. The pharmacological targeting of PDGFR may be a new strategy to treat eosinophilic disorders.

Aminophilline suppress the release of chemical mediators in treatment of acute asthma.

BACKGROUND: The control of airway inflammation is crucial for management of asthma. Theophylline has been demonstrated to have an anti-inflammatory effect as a long-term-medication for asthma in various studies. In the present study we attempted to clarify if aminophylline, a theophylline derivative, could act as an anti-inflammatory agent as well as a bronchodilator in the treatment for acute asthma exacerbations. METHODS: Patients are initially treated either with an intravenous infusion of aminophylline or with inhalation of salbutamol. Pro-inflammatory mediators such as eosinophil cationic protein (ECP), histamine, serotonin, thromboxane B2, leukotriene C4 were measured before and one hour after the initial treatment. Clinical parameters such as peak expiratory flow (PEF) and SpO2 were also checked during the studies. RESULTS: Significant improvements of PEF and SpO2 with both aminophylline and salbutamol treatment were seen. Furthermore, significant decreases of ECP, histamine, and serotonin were observed with aminophylline but not with salbutamol. CONCLUSIONS: Suppressing the release of pro-inflammatory mediators may play a role, at least in part, in the beneficial effects of aminophylline in the treatment of acute exacerbations in asthma. Additionally, this study indicated that treatment with aminophylline is at least as beneficial as nebulized salbutamol in the restoration of lung function.