Bradykinin B(2) receptor gene polymorphism is associated with angiotensin-converting enzyme inhibitor-related cough.
The appearance of cough in association with angiotensin-converting enzyme (ACE) inhibitors is thought to be related to bradykinin, and it has been speculated that the elicitation of adverse effects is genetically predetermined. Several polymorphisms of the human bradykinin B(2) receptor gene may be involved in ACE inhibitor-related cough. To investigate this possibility, we identified the -58 thymine (T)/cytosine (C) polymorphism in subjects with ACE inhibitor-related cough. We classified the study population into 4 groups: subjects with and without cough that were treated with ACE inhibitors (n=30/30), nontreated essential hypertensive subjects (n=100), and normotensive subjects (n=100). The -58T/C was genotyped by the polymerase chain reaction single-strand conformation polymorphism method. The frequencies of the CC genotype and C allele of -58T/C were significantly higher in the nontreated hypertensive subjects than in the normotensive subjects. Conversely, the frequencies of the TT genotype and T allele were significantly higher in the subjects with cough than in the subjects without cough. These tendencies were more pronounced in females. Among the promoter assays of the human bradykinin B(2) receptor, -58T was found to have a higher transcription rate than that of -58C. This finding seems to suggest that the transcriptional activity of promoter might be involved in the appearance of ACE inhibitor-related cough. A genetic variant of the bradykinin receptor is involved in the elicitation of ACE inhibitor-related cough. It may be possible to predict the side effects of ACE inhibitors in advance. (+info)
Frequency of serological evidence of Bordetella infections and mixed infections with other respiratory pathogens in university students with cough illnesses.
Banked acute-phase and convalescent-phase serum samples from a previous study of respiratory illness in university students were examined for significant (>/=2-fold) increases in ELISA titers of IgA and IgG antibody to Bordetella pertussis filamentous hemagglutinin, pertactin, and fimbriae-2 and >/=4-fold titer increases to agglutinogens by agglutination. ELISA titers of antibody to pertussis toxin could not be determined because of technical problems. Chlamydia pneumoniae infections were diagnosed by culture or by a >/=4-fold increase in immunofluorescence assay titer or a single high titer (>/=512). Mycoplasma pneumoniae, influenza A and B, adenovirus, and respiratory syncytial virus infections were diagnosed by >/=4-fold increases in complement fixation titer or a single high titer (>/=64). There were 319 subjects with cough of >/=5 days' duration, and of these, 47 (15%) had significant increases in antibody to B. pertussis antigens; 26 (8%) had significant increases to fimbriae-2 or agglutinogens, indicative of B. pertussis infection, and 2 (1%) had evidence of non-B. pertussis bordetella infections. Seventeen (36%) had evidence of mixed infections or cross-reacting antibodies (influenza B infections, 5; adenovirus infections, 4; influenza A infections, 3; C. pneumoniae infections, 3; and M. pneumoniae infections, 2). Our findings suggest that bordetella infections are common in young adults with cough illnesses (incidence, 9%), and a surprising number of these are mixed infections with other respiratory pathogens. (+info)
Bronchiolitis obliterans-organizing pneumonia: an Italian experience.
The purpose of this study was to describe the clinical features at onset and outcome and the diagnostic approach in subjects with bronchiolitis obliterans-organizing pneumonia (BOOP). Over a 7-year period we observed 78 cases of biopsy-proven bronchiolitis obliterans-organizing pneumonia, in which well documented clinical and radiographic data were available. The final diagnosis of BOOP was validated when patients presented: (i) negative microbiological analysis on BAL fluid; (ii) a well documented improvement either spontaneous, or after steroid treatment or (iii) cases with progressive respiratory failure and increasing radiographic shadows, an open lung biopsy or autopsy that excluded other entities. There were 42 males and 36 females; the mean age was 61+/-12 years (range 12-85 years). Forty-two (54%) patients were current smokers, 25 (32%) had never smoked and 11 (14%) were ex-smokers. The clinical pattern at presentation of BOOP was more frequently similar to classical acute or sub-acute infectious pneumonia. Fever (63%), dyspnoea (58%) and dry cough (53%) were the typical symptoms on admission. A flu-like syndrome preceeding BOOP was observed in 21 cases (27%). Inspiratory crackles (78%) were the most typical finding at physical examination. However, 13% of the patients were asymptomatic and an abnormal chest X-ray film was the reason for seeking medical attention. Radiographically the most frequent pattern of BOOP was a unilateral consolidation (44%) with lower field predominance. A migratory behaviour was present in 22% of the cases. High-resolution computed tomographic (HR-CT) scan when performed, was more sensitive in detecting ground glass infiltrates, sub-pleural or peri-bronchovascular distribution or the presence of nodules or cavitation. Most patients (68%) were classified as having idiopathic BOOP. However, the same clinical-roentgenological pattern was observed in patients after radiotherapy for ductal breast carcinoma (6%), in collagen-vascular diseases (6%), related to drugs (9%), to infections serologically documented (4%), and to graft vs. host disease (4%). Four patients (all of whom had idiopathic BOOP) presented a rapid progressive respiratory failure needing mechanical ventilation. In another two cases respiratory failure appeared after a long period during which patients experienced exertional dyspnoea and low grade fever. BAL profile was characterized by lymphocytosis with a reduction of the CD4/CD8 ratio, associated with a slight increase of neutrophils and eosinophils and scattered mast cells. However in two cases we had an increased CD4/CD8 ratio and in one case the presence of a significant 12% of polyclonal B cells. In a few cases atypical (cytokeratin-positive cells) epithelial cells were detected: these cells were constantly present in the BAL fluid of patients with rapidly progressive respiratory failure. From the diagnostic point of view this series documents that transbronchial lung biopsy (coupled with BAL) can be the first diagnostic step. However, therapy can be started on the basis of BAL data (when a characteristic morphological and phenotypical profile is evident) in cases in which the clinical presentation is suggestive and a biopsy cannot be made. Most patients showed a rapid and good response to steroid therapy. However, three patients died (4%) in spite of steroid therapy (two cases) and steroid and cyclophosphamide therapy (one case). In conclusion, although clinical findings, chest X-ray film and CT Scan findings usually suggest the diagnosis a definite confirmation requires transbronchial lung biopsy and BAL and, less frequently, open lung biopsy. (+info)
Volume-timing relationships during cough and resistive loading in the cat.
The relationship between pulmonary volume-related feedback and inspiratory (CTI) and expiratory (CTE) phase durations during cough was determined. Cough was produced in anesthetized cats by mechanical stimulation of the intrathoracic tracheal lumen. During eupnea, the animals were exposed to single-breath inspiratory and expiratory resistive loads. Cough was associated with large increases in inspiratory volume (VI) and expiratory volume (VE) but no change in phase durations compared with eupnea. There was no relationship between VI and CTI during coughing. A linear relationship with a negative slope existed between VI and eupneic inspiratory time during control and inspiratory resistive loading trials. There was no relationship between VE and CTE during all coughs. However, when the first cough in a series or a single cough was analyzed, the VE/CTE relationship had a positive slope. A linear relationship with a negative slope existed between VE and eupneic expiratory time during control and expiratory resistive loading trials. These results support separate ventilatory pattern regulation during cough that does not include modulation of phase durations by pulmonary volume-related feedback. (+info)
Chlamydia pneumoniae infection in adults with chronic cough compared with healthy blood donors.
In a small uncontrolled study, persistent cough has recently been found to be associated with serological evidence of acute Chlamydia pneumoniae infection. In order to assess whether C. pneumoniae plays a role in chronic cough, the prevalence of C. pneumoniae infection in 201 adult patients with chronic cough was compared with the prevalence in 106 healthy blood donors without respiratory tract symptoms in the preceding 3 months. A microimmunofluorescence antibody test was used to determine C. pneumoniae antibodies in the immunoglobulin (Ig)M, IgG and IgA fractions. Further, nasopharyngeal aspirates from the 201 patients were examined for C. pneumoniae deoxyribonucleic acid by polymerase chain reaction (PCR). As judged by serology, nine patients (4%) and one control (1%) had acute C. pneumoniae infection, and 92 patients (46%) and 42 controls (40%) had previous or chronic C. pneumoniae infection. Of the nine patients with acute infection, three were C. pneumoniae PCR positive, and they all had an IgM antibody titre response. The remaining six patients had either an IgG antibody titre of > or =512 (five patients) or an IgA antibody titre of > or =512 (one patient). None of these six patients had detectable IgM antibodies. The mean cough period for the five IgG positive patients (10.8 weeks) was significantly longer than the mean cough period for the remaining patient population (6.4 weeks; p=0.004). It is concluded that Chlamydia pneumoniae infection was not statistically significantly more prevalent in patients with chronic cough than in healthy blood donors, and that Chlamydia pneumoniae appears to have a minor role in patients with chronic cough. Direct detection of Chlamydia pneumoniae by polymerase chain reaction on nasopharyngeal aspirates is highly correlated with detectable immunoglobulin M antibodies, but in the late stages of prolonged cough serological testing of immunoglobulin G and immunoglobulin A may be more beneficial for obtaining a microbiological diagnosis. (+info)
Investigation of an acute chemical incident: exposure to fluorinated hydrocarbons.
OBJECTIVES: To assess whether attendance at the site after an incident in a sewer was associated with symptoms in emergency personnel and whether the prevalence of symptoms was associated with estimated levels of exposure to any chemical hazard. METHODS: Symptoms experienced by people attending an incident involving two dead sewer workers suggested the presence of a chemical hazard, before environmental sampling confirmed any toxic agent. Self reported symptoms, estimated exposures, and biomarkers of exposure for likely agents from all 254 people who attended the incident and a referent occupational group matching the 83 emergency personnel who went to the Accident and Emergency department (A and E) in the first 48 hours were recorded. The prevalence of symptoms and concentrations of creatine phosphokinase in serum of the 83 early patients at A and E were compared with their referent occupational group. In all workers who attended the incident, the trends in symptom prevalences and concentrations of creatine phosphokinase in serum were examined by distance from the site and predefined exposure category. RESULTS: Among all workers who attended the incident, symptoms of shortness of breath and sore throat were significantly associated with indirect estimates of exposure but not associated with concentrations of creatine phosphokinase. Freon was detected in two blood samples. The early patients at A and E reported more symptoms than their matched reference group and their median concentrations of creatine phosphokinase were higher. CONCLUSIONS: The association between symptoms and concentrations of creatine phosphokinase with attendance at the site indicated the presence of a continuing hazard at the site and led to extra precautions being taken. Comparison values from the referent occupational group prevented unnecessary medical follow up. (+info)
Beclomethasone dipropionate in asthma.
Beclomethasone dipropionate aerosol therapy can replace or diminish systemic corticosteroid therapy in the majority of asthmatics. In a clinical trial of 41 patients with perennial asthma, the 10 who had not required long-term corticosteroid therapy improved symptomatically and in pulmonary function. Of the 31 who had required prolonged systemic corticosteroid therapy 12 were able to discontinue oral prednisone therapy, 15 were able to decrease the maintenance dose of prednisone and only 4 were unable to decrease the dose; all maintained satisfactory lung function and some showed improvement. Discontinuation of systemic corticosteroid therapy was accomplished more readily in patients whose daily maintenance dose was less than 15 mg and who had been taking the drug for less than 3 years. Side effects consisted of a "dry throat" in seven patients, two of whom had throat infections with Candida albicans. Recurrence of rhinitis after discontinuation or reduction of systemic corticosteroid therapy was noted in 11 patients. (+info)
Participation of thromboxane A(2) in the cough response in guinea-pigs: antitussive effect of ozagrel.
1. The purpose of this study was to investigate the involvement of thromboxane A(2) (TXA(2)) in the cough response in a guinea-pig cough model. Here, we describe results obtained using a selective TXA(2) synthetase inhibitor, ozagrel, and a selective TXA(2) agonist, U-46619. 2. Guinea-pigs were anaesthetized and exposed to an aerosol of capsaicin (100 microM) to elicit coughing. The number of coughs was 20.0+/-5.8 during capsaicin provocation (5 min), but only 2. 8+/-0.4 during a 5-min inhalation of phosphate-buffered saline (PBS) (P:<0.05). 3. TXB(2) levels in BAL were 101.4+/-8.0 and 58.4+/-8.7 pg ml(-1) following capsaicin and PBS inhalation, respectively (P:<0. 01), but there was no intergroup difference in the cell populations in BAL. 4. Inhalation of U-46619 did not induce a cough response by itself at concentrations of 100 ng ml(-1) to 10 microg ml(-1). However, it caused a 2 fold increase in the number of capsaicin-induced coughs. 5. To explore the source of the TXA(2), BAL cells were stimulated with capsaicin and the supernatants collected for analysis. The TXB(2) concentration in BAL was increased dose-dependently, indicating that TXA(2) is released from BAL cells in response to capsaicin. 6. Ozagrel was administered orally 1 h before a 5 min capsaicin provocation and the number of coughs was counted during the capsaicin inhalation. Ozagrel decreased the number of coughs dose-dependently (ED(50) value, 26.3 mg kg(-1)). 7. These results show that TXA(2) modulates the capsaicin-induced cough response by increasing capsaicin-sensitivity. (+info)