Eosinophils, mast cells, and basophils in induced sputum from patients with seasonal allergic rhinitis and perennial asthma: relationship to methacholine responsiveness

OBJECTIVES

We attempted to determine whether inflammation is present in induced sputum of patients with seasonal allergic rhinitis (AR) as compared with those with perennial asthma (AS) and examined its relationship with bronchial responsiveness to methacholine.

METHODS

Sputum was induced in 30 patients with seasonal rhinitis in response to grass pollens only and in 15 patients with stable, asymptomatic asthma. The AR group was divided according to methacholine PD20 value: the AR- group (n = 15) had a methacholine PD20 greater than 24 micromol; the AR+ group (n = 15) had a methacholine PD20 ranging between 2.2 and 19.6 micromol. In the AS group, methacholine PD20 ranged between 0.42 and 2.6 micromol. The percentage of eosinophils and metachromatic cells (alcian blue-positive) was assessed in sputum by light microscopy. Tryptase-positive cells and EG2+ cells were identified by immunocytochemistry with the mouse anti-human mast cell-tryptase monoclonal antibody and the monoclonal anti-eosinophil cationic protein antibody.

RESULTS

We found that the number of eosinophils in the AS group was greater than that in the AR+ group (p < 0.05) and in the AR- group (p < 0.01). Moreover, the eosinophil count was lower in the AR- group compared with the AR+ group (p < 0.05). Similarly, the number of EG2+ cells was greater in the AS group than in the AR group (p < 0.02) and the AR- group (p < 0.05). Moreover, the EG2+ cell count was lower in the AR- group than in the AR+ group (p < 0.05). The number of mast cells and basophils in the AS group was greater than that in the AR group (p < 0.05 and p < 0.01, respectively). Mast cells in sputum were tryptase-positive. Basophils were present in sputum from 23% of patients with AR and 53% of patients with asthma. There was a significant correlation between methacholine PD20 and eosinophils (p < 0.005) and mast cells (p < 0.02) but not with basophils in those patients showing a measurable methacholine PD20 (AR+ and AS groups).

CONCLUSIONS

Inflammatory cells are present not only in the airways of patients with asthma but also in airways of patients with seasonal AR, even outside natural exposure. Moreover, we provide evidence for the presence of basophils in sputum of patients with asthma even during clinical remission. The presence of bronchial responsiveness is associated with an increase in the number of eosinophils and metachromatic cells. Our findings are consistent with the hypothesis that eosinophils, as well as mast cells, contribute to bronchial responsiveness not only in AS but also in seasonal AR.

Effect of short-term treatment with low-dose inhaled fluticasone propionate on airway inflammation and remodeling in mild asthma: a placebo-controlled study

In a double-blind, parallel-group study, we examined the effect of short-term treatment with inhaled fluticasone propionate (FP) in a group of 20 nonsmoking asthmatic patients who required only beta2-agonists to control their symptoms. We administered FP (250 microg twice daily) or matched placebo for 6 wk. Methacholine challenge was performed before treatment, after 3 wk, and at the end of treatment. Each patient underwent bronchoscopy with bronchoalveolar lavage (BAL) and bronchial biopsy before and after treatment. Eight patients in the placebo group and nine patients in the FP group completed the study. Bronchial responsiveness to methacholine decreased significantly only after 6 wk of treatment with FP (p < 0.05). When we compared the FP group with the placebo group, we observed a significant decrease only in the number of cells expressing intracellular adhesion molecule-1 (ICAM-1) and MAC-1 (p < 0.04 and p < 0.03, respectively). Moreover, we saw that the tryptase level in BAL decreased (p < 0.001), whereas the eosinophil cationic protein (ECP) level did not change significantly. Additionally, the number of eosinophils and mast cells in the lamina propria in bronchial biopsies specimens was significantly smaller in the FP group than in the placebo group (p < 0.02 and p < 0.01, respectively). Additionally, in the FP group, we found that basement-membrane thickness was significantly decreased when compared with that of the placebo group (p < 0.05). In conclusion, our results show that short-term treatment with low-dose FP reduces inflammatory cell infiltration into the lamina propria in bronchial biopsy specimens. Moreover, short-term low-dose FP treatment might control the intensity of airway remodeling in mild asthma.

Lung epithelial permeability and bronchial responsiveness in subjects with stable asthma

Lung epithelial permeability of asthmatic patients has been reported to be similar or lower than that of healthy subjects and to be correlated or not to bronchial hyperresponsiveness. To clarify these discrepancies, we evaluated 99mTc-DTPA pulmonary clearance in a group of carefully selected asthmatic patients with mild, stable asthma (n = 13; seven women; mean age +/- SD = 27.69 +/- 6.63 years), and compared them with a group of healthy, nonsmoking subjects (n = 8; six women; mean age +/- SD = 24.38 +/- 5.15 years). Selection criteria for asthmatics were as follows: baseline FEV1 > or = 80% of predicted values, no bronchial infections, and/or no asthma attacks during 4 weeks prior to study and peak expiratory flow rate variability lower than 20%, over a period of 3 weeks. Patients controlled symptoms with beta 2-adrenergic drugs only, regularly or on demand. Mean baseline FEV1 (+/-SD) as percent of predicted was 102.38 +/- 13.97 and 112.88 +/- 18.36, respectively (p < 0.05). In the asthmatic group, bronchial responsiveness to methacholine (PC20 M FEV1) ranged between 0.55 and 28.5 mg/mL. Mean value (+/-SD) of DTPA clearance from lungs to blood (evaluated on the first 10 min out of 30 min of the curves) in the asthmatic group was not different from that of control group (68.31 +/- 21.46 and 69.5 +/- 15.73). In the asthmatic patients, there was no correlation between PC20 M values and DTPA T1/2 min of the whole lung, nor between PC20 M and inner and outer lung clearance zones. Moreover, both in asthmatics and healthy subjects, DTPA clearance of outer (alveolar) zones was significantly faster than that of inner (bronchial) zones (57.69 +/- 19.94 vs 102.08 +/- 38.19, p < 0.001, and 59.75 +/- 12.49 vs 103.5 +/- 31.86, p < 0.003, respectively). Our data show that DTPA clearance in patients with stable asthma is similar to that found in healthy subjects; it is not correlated to degree of bronchial responsiveness and occurs more rapidly in the outer zones than in the inner zones, both in asthmatic patients and in healthy subjects. Thus, to date, DTPA clearance index is not a valid tool for identifying and/or monitoring asthmatic patients.

Airways remodeling is a distinctive feature of asthma and is related to severity of disease

PURPOSE

Airways remodeling, evaluated as the subepithelial layer thickness, was compared in asthmatic patients with that of healthy subjects, and was related to clinical grading of disease, presence of atopy, and length of asthmatic history.

SUBJECTS AND METHODS

Thirty-four patients with stable asthma (mean age+/-SD: 26.5+/-9.2 years; 10 female) treated with only inhaled beta2-agonists and eight healthy volunteers (mean age+/-SD: 24.6+/-2.5 years; four female) were recruited for the study. Twenty-seven of 34 asthmatics had atopy. Eleven patients had newly diagnosed conditions (duration of disease < or = 1 year), nine patients had long asthmatic history (> 1 year and < or = 10 years), and 14 had prolonged asthmatic history (> 10 years). Bronchial responsiveness to methacholine (M) was expressed as provocative concentration of M causing a 20% fall in FEV1 (PC20) (mg/mL). Degree of asthma severity was assessed using a 0- to 12-point score based on symptoms, bronchodilator use, and daily peak expiratory flow variability over a 3-week period. Bronchoscopy and bronchial biopsy were performed successfully for all subjects; the subepithelial layer thickness, in biopsy samples, was measured from the base of bronchial epithelium to the outer limit of reticular lamina.

RESULTS

In asthmatics, baseline FEV1 values (percent of predicted) ranged from 75.7 to 137.0%, and PC20 M ranged from 0.15 to 14.4 mg/mL. According to the asthma severity score, 14 asthmatics were classified as having mild disease, 14 as having moderate disease, and six as having severe disease. The mean values of subepithelial layer thickness were 12.4+/-3.3 microm (range, 6.8 to 22.1 microm) in asthmatics, and 4.4+/-0.5 microm (range, 3.8 to 5.2 microm) in healthy subjects (p<0.001). Subepithelial layer thickness of those with severe asthma differed significantly from that of patients with moderate and mild asthma (16.7+/-3.1 microm vs 12.1+/-2.7 microm and 10.8+/-2.4 microm, p<0.01 and p<0.003, respectively). Moreover, in asthmatics, degree of thickening was positively correlated to asthma severity score (Spearman rank correlation coefficient [rs]=0.581; p<0.001), and negatively correlated with baseline FEV1 (rs=-0.553; p<0.001) and PC20 M (rs=-0.510; p<0.01). No difference was found between degree of thickening observed in atopic asthmatics, compared with that of nonatopic asthmatics, or between degree of thickening in patients with different lengths of asthmatic history. Lastly, multiple regression analysis revealed that asthma severity score was the significant predictive factor for thickness of subepithelial layer.

CONCLUSIONS

We confirmed that airways remodeling is a very distinctive and characteristic pathologic finding of asthma. We also demonstrated that it is related to the clinical and functional severity of asthma, but not to atopy or length of asthmatic history.

Effect of inhaled furosemide and cromolyn on bronchoconstriction induced by ultrasonically nebulized distilled water in asthmatic subjects

BACKGROUND

Inhaled furosemide has been shown recently to produce a protective effect against bronchoconstriction induced by several indirect stimuli, including ultrasonically nebulized distilled water (UNDW). Since there is a close parallel between its experimental effects and those reported for cromolyn,/it has been suggested that they may share some common mechanisms of action. Their protective effect, however, has never been compared directly. In this study, therefore, we have investigated the ability of equal doses (30 mg) of inhaled furosemide and cromolyn to modulate bronchoconstriction induced by UNDW in a group of ten asthmatic patients.

METHODS

Subjects with documented bronchial response to UNDW were enrolled in a randomized, double-blind, placebo-controlled study. Treatments were administered five minutes prior to increasing outputs of UNDW and the response was expressed as the provocative output causing a 20% fall in FEV1 (PO20, in mL/min) and as the output-response slope.

RESULTS

Geometric mean PO20 increased from 1.53 to 4.05 mL/min (P < .0004) after furosemide. After inhaling the highest output of UNDW (5.2 mL/min), PO20 was not measurable in six of ten patients when pretreated with furosemide and in all patients when pretreated with cromolyn. This difference was statistically significant (P < .05). Geometric mean values of output-response slope significantly decreased from 13.6 to 2.97 after furosemide (P < .0001) and from 13.6 to 1.43 (P < .0002) after cromolyn.

CONCLUSIONS

These results suggest that cromolyn has a slightly greater anti-reactive activity in UNDW-induced bronchoconstriction compared to furosemide.

Once daily intranasal fluticasone propionate (200 micrograms) reduces nasal symptoms and inflammation but also attenuates the increase in bronchial responsiveness during the pollen season in allergic rhinitis

BACKGROUND

Fluticasone propionate aqueous nasal spray, a new topical corticosteroid, has been proved to be an effective treatment for seasonal allergic rhinitis.

OBJECTIVES

We studied the effect of fluticasone propionate on nasal symptoms, circulating eosinophils, and nasal inflammation in patients with seasonal allergic rhinitis after high-load pollen exposure. Moreover, we examined its efficacy in preventing the increase in bronchial responsiveness to methacholine (PD20) during the pollen season.

METHODS

We conducted a double-blind, placebo-controlled, parallel-group study in patients who had a history of allergic rhinitis in response to pollens of grass and Parietaria species and were living in northern Italy. After a run-in period of 2 weeks, 24 patients were treated with fluticasone propionate (200 micrograms, once daily), and 26 patients received matched placebo for 6 weeks, starting from the beginning of the pollen season. Assessment of efficacy was based on scores of daily nasal symptoms. Nasal lavage was performed at the end of the season, and differential cell count was expressed as percent of total cells. PD20 methacholine was measured at the beginning and end of the season and after the season had ended.

RESULTS

Fluticasone propionate significantly reduced nasal obstruction, itching, and rhinorrhea. Eosinophils in blood (p < 0.01) and nasal lavage (p < 0.001) were also reduced. Moreover, fluticasone significantly attenuated the decrease in mean PD20 methacholine (from 1.95 to 0.89 mg) compared with placebo (from 1.38 to 0.37 mg: p < 0.01). After the season, no difference in PD20 methacholine was found between treatment groups.

CONCLUSIONS

The results of this study indicate that fluticasone propionate is effective in decreasing nasal symptoms and eosinophil inflammation in patients with seasonal allergic rhinitis after high-load pollen exposure. Our results also demonstrate that treatment with fluticasone propionate partially prevents the increase in bronchial responsiveness provoked by the inhalation of seasonal pollens in allergic rhinitis.

Effect of acetazolamide on cough induced by low-chloride-ion solutions in normal subjects: comparison with furosemide

BACKGROUND

The antitussive activity of inhaled furosemide has been attributed to its blocking effect on the Na(+)-2Cl(-)-K+ cotransporter. It is likely that the antitussive activity of inhaled diuretics is more complex because amiloride, a diuretic that has no effect on the Na(+)-2Cl(-)-K+ cotransporter, also shows a significant effect against cough induced by low-chloride-ion solutions. Apart from pharmacokinetics of inhaled diuretics, this activity could also depend on the inhibition of carbonic anhydrase.

OBJECTIVES

We therefore studied the effect of inhaled acetazolamide, a selective inhibitor of carbonic anhydrase activity, on cough induced by the inhalation of different chloride ion solutions in a group of normal subjects. This was compared with the antitussive effect of furosemide. In addition, we attempted to determine whether the effect of acetazolamide is dose-dependent.

METHODS

Cough challenge consisted of consecutive inhalations of four solutions having decreasing concentrations of chloride ions (150, 75, 37.5 and 0 mmol/L). Nine normal subjects underwent the cough challenge 5 minutes after the inhalation of saline placebo, acetazolamide (500 mg), and furosemide (30 mg) according to a randomized, double-blind study design. A group of six subjects were challenged according to the same procedure and study design, after the inhalation of saline placebo and of two doses of acetazolamide (250 mg and 500 mg).

RESULTS

Inhaled acetazolamide significantly reduced cough response to 37.5 and 0 mmol/L chloride solutions compared with placebo (p less than 0.015 and p less than 0.015, respectively). Furosemide showed a similar protective effect (p less than 0.015 and p less than 0.025, respectively). Acetazolamide provided a significantly better protective effect than furosemide (p less than 0.025 and p less than 0.015, respectively). The antitussive activity of the two doses of acetazolamide was not statistically different.

CONCLUSION

These results demonstrate that inhaled acetazolamide, a selective inhibitor of carbonic anhydrase, attenuates cough induced by low-chloride-ion solutions in normal subjects. At the applied doses, its antitussive activity is slightly greater than furosemide. This finding suggests that the inhibition of carbonic anhydrase activity is likely involved in modulating changes caused by absence of a chloride ion in the airway microenvironment of human beings.

Bronchial responsiveness to distilled water and methacholine and its relationship to inflammation and remodeling of the airways in asthma

Although bronchial hyperresponsiveness in asthma is associated with inflammation within the airways, it is not known whether the degree and type of inflammation influence the response to different stimuli and whether pathologic changes of airway structure influence the bronchoconstrictive responses. Therefore, number of inflammatory cells in the epithelium and the lamina propria and the basement membrane thickness were estimated from bronchial biopsies taken in 27 asthmatic subjects (range percent predicted FEV1: 75.6 to 132.1, range of daily PEF variability: 1.9% to 20%) and related to the degree of bronchial responsiveness to ultrasonically nebulized distilled water (UNDW) and methacholine (M). PD20UNDW (provocative dose) was measurable in 15 of 27 patients and ranged between 1.01 and 20.4 ml. PC20M (provocative concentration) ranged between 0.15 and 31.7 mg/ml. In the 15 responders to UNDW, total inflammatory cells (p<0.04) and eosinophils (p<0.015) within the epithelium were higher than in 12 nonresponders to UNDW (PD20 > 34.8 ml). There was no correlation between PD20UNDW and any cell counts whereas negative correlations were found between PC20M and both total inflammatory cells (rs = -0.57; p<0.005) and eosinophils (rs = -0.63; p< 0.0015) within the epithelium. The degree of thickening of subepithelial layer ranged between 7 and 16 micrometers+ (n=26). Thickness correlates both with total inflammatory cells (rs = 0.49; p<0.025) and eosinophils (rs = 0.61; p< 0.003) within the epithelium. Moreover, it was correlated with baseline FEV1 (rs = -0.57; p<0.003) and daily peak expiratory flow (PEF) variability (rs = 0.51; p<0.01). A weak but significant correlation was also found between subepithelial layer thickness and PC20M (rs = -0.42; p<0.04). The results of this study demonstrate that eosinophilic inflammation of bronchial epithelium plays a role in determining UNDW and M responsiveness in asthma. Moreover, they suggest that remodeling of the airways such as thickening of subepithelial layer correlates with indices of asthma severity and could contribute to the degree of M but not to UNDW responsiveness.

Prevalence and repeatability of the cough response induced by inhalation of low chloride ion solutions in normal subjects

Although the inhalation of low Cl- ion solutions has often been used to induce cough, the prevalence and repeatability of the challenge has never been studied in detail. We, therefore, examined cough response in a group of 59 volunteers (aged 15-57 yrs; 34 females and 25 males; 20 smokers) to ascertain prevalence and repeatability. Each subject performed, 2 weeks apart, two identical cough challenges by inhaling four isosmolar solutions with decreasing Cl- ion concentrations (150, 75, 37.5 and 0 mM). Each solution was delivered by a DeVilbiss 65 ultrasonic nebulizer (mean output: 1.9 mL.min-1) for 1 min, and the number of coughs was counted during the inhalation. Cough response was expressed as number of coughs.min-1. Significance of response to the cough challenge was assessed on the basis of mean number of coughs.min-1 and 95% upper confidence limit (CL) of response to the Cl- free solution in the whole population. Cough threshold for a significant response was greater than 8 coughs.min-1. Out of 59 subjects, only 20 exceeded the cough threshold (34%) after inhaling the Cl- free solution. A concentration-response effect was evident only when inhaling 37.5 and 0 mM Cl- ion solutions. A significant cough response was more likely among females (p = 0.03). Smoking did not significantly affect the prevalence of response. Coefficients of repeatability of cough response to 37.5 and 0 mM Cl- solutions in 20 responders were equal to 10.1 and 12.6, respectively. We conclude that a significant cough response to low Cl- ion solutions develops in approximately 1 out of 3 of challenged volunteers and that repeatability is not satisfactory. We suggest that cough threshold and repeatability should be preliminarily assessed, especially when the challenge is used to study the antitussive activity of drugs.

Effect of intranasal azelastine and beclomethasone dipropionate on nasal symptoms, nasal cytology, and bronchial responsiveness to methacholine in allergic rhinitis in response to grass pollens

BACKGROUND

We compared the effect of nasal azelastine (0.56 mg/day), nasal beclomethasone dipropionate (BDP, 200 micrograms/day) and matched placebo on seasonal symptoms, nasal cytology, and the increase in bronchial responsiveness occurring during pollen season in a group of subjects with history of allergic rhinitis to grass pollens only.

METHODS

The study was completed by nine subjects in the azelastine group, 13 subjects in the BDP group, and 13 subjects in the placebo group. Treatments were randomly administered for 6 weeks. Each subject recorded daily nasal, eye and chest symptoms and additional treatment requirement for the entire pollen season. Each subject performed nasal lavage 4 weeks into the pollen season. Bronchial responsiveness to methacholine was measured before and 4 weeks into the pollen season. Response was expressed as provocative dose causing a 20% fall in forced expiratory volume in 1 second in micromoles.

RESULTS

Azelastine-treated subjects had significantly fewer nasal symptoms during week 4 (p < 0.05), and BDP-treated subjects had fewer nasal symptoms during week 4 (p < 0.05) and week 5 (p < 0.05) compared with subjects given placebo. Both treatments significantly reduced the need for additional medications. BDP, but not azelastine, treatment significantly reduced the percent of eosinophils recovered in nasal lavage (p < 0.05). Neither azelastine nor BDP protected against the increase in bronchial responsiveness to methacholine occurring during the pollen season.

CONCLUSION

We demonstrated that both azelastine and BDP are effective treatments for nasal symptoms of seasonal allergic rhinitis after 4 weeks of therapy. However, we were not able to demonstrate an antiinflammatory activity of nasally administered azelastine. Nasal therapy with azelastine and BDP did not block the increase in bronchial responsiveness to methacholine caused by seasonal allergen exposure.

Lung function and diffusing capacity for carbon monoxide in patients with juvenile chronic arthritis: effect of disease activity and low dose methotrexate therapy

OBJECTIVE

We measured lung function, in terms of lung volumes, forced expiratory flow-volume curves and diffusing capacity of carbon monoxide (DLCO), in a group of 61 patients with juvenile chronic arthritis (42 female; age range 5 to 33 years) to ascertain whether disease activity and treatment with low dose methotrexate (MTX) influenced these parameters. The whole population was divided into subgroups based on onset type (systemic, n = 27; pauciarticular, n = 12; polyarticular, n = 22), disease activity (active, n = 42; inactive, n = 19), and MTX treatment (treated, n = 27; not treated, n = 34).

RESULTS

We found that maximal-mid expiratory flow (MMEF) was significantly reduced in patients with active disease (p < 0.025). The mean DLCO value, expressed as a percentage of the predicted value, and DLCO corrected for the hemoglobin value were lower than expected (67% and 80%, respectively). Multiple regression analysis showed that the forced vital capacity (FVC), forced expiratory flow in one second (FEV1) and DLCO were all correlated to the clinical subtype of the disease (p < 0.05, p < 0.02, p < 0.02, respectively), and MMEF was related to disease activity (p < 0.025). There was no evidence of any effect of MTX treatment on the pulmonary parameters.

CONCLUSION

This study confirms that JCA is characterized by an impairment of lung function, mainly involving the small airways, and by interstitial damage. These changes are related to the clinical subtypes of the disease and to disease activity.

Involvement of neurogenic inflammation in antigen-induced bronchoconstriction in guinea pigs

The role of tachykinins released from sensory nerves in bronchoconstriction induced by antigen was studied in sensitized guinea pigs anesthetized with pentobarbital sodium and pretreated with atropine. The combination of NK2 (SR-48968) and NK1 (CP-96,345) tachykinin-receptor antagonists abolished the increase in total pulmonary resistance (RL) evoked by intravenous capsaicin but did not affect the response evoked by intravenous histamine. A small dose of aerosolized ovalbumin (OVA, 0.1%) produced a small increase in RL that was further increased and markedly prolonged by the neutral endopeptidase (NEP) inhibitor phosphoramidon; this bronchoconstrictor effect of OVA was markedly reduced by the NK2-receptor antagonist and was abolished by the combination of the NK1 and NK2-receptor antagonists together. When a larger dose of OVA (0.5%) was used, a maximal bronchoconstrictor response was obtained. Phosphoramidon did not potentiate this response significantly. The combination of NK1- and NK2-receptor antagonists blunted the response at 5 min only slightly but markedly attenuated the later (10-20 min) response. These results show that tachykinins released from sensory nerves play a significant role in antigen-induced bronchoconstriction in guinea pigs. This effect is exaggerated when the normal modulation of neuropeptides by NEP is inhibited and is mediated predominantly by NK2-receptor activation, with a smaller contribution by NK1 receptors.

Calcium channel autoantibodies in myasthenic syndrome and small cell lung cancer

Lambert-Eaton myasthenic syndrome (LEMS) is one of the neurologic paraneoplastic syndromes often found in patients with lung cancer. It is characterized by a generalized deficit of neurotransmitter release. Patients with small cell lung cancer (SCLC) in particular may develop LEMS, and SCLC is very often detected in patients affected by LEMS. LEMS is an autoimmune disease, and autoantibodies that interfere with neurotransmitter release by binding to presynaptic voltage-operated calcium channels (VOCCs) have been found in sera of patients with LEMS. Both human neuronal and SCLC cell lines express omega-conotoxin-sensitive VOCCs, and autoantibodies from patients affected by LEMS can precipitate these channels. We have now screened a large population of patients and control subjects in order to define the specificity and sensitivity of the anti-VOCC antibody assay. We have tested sera from 52 patients with LEMS with and without SCLC; 32 sera from patients with SCLC without LEMS, 31 from patients with non-SCLC, 34 from patients with inflammatory lung diseases, 17 from patients with other neurologic disorders, and 48 from healthy control subjects. We have found that a positive result with this radioimmunoassay is highly specific for LEMS, with or without SCLC, when the antibody titer is higher than 14.21 pM. Anti-VOCC antibodies have also been found in about 40% of patients with SCLC without LEMS, but they were absent in all the other populations tested. We can conclude that this serologic assay is a very useful aid in the diagnosis of LEMS, and it might be useful also for the early diagnosis of SCLC.

Reproducibility of allergen-induced asthma and associated increase in bronchial responsiveness to methacholine in asthmatic children

We studied the reproducibility of early (EAR) and late (LAR) asthmatic response to allergen challenge in 13 asthmatic children (four girls, age range: 10 to 17 years) sensitized only to Dermatophagoides pteronyssinus (Dp). Further, changes in bronchial responsiveness to inhaled methacholine following LAR were examined by measuring PC20FEV1 methacholine after 24, 48, and 72 hours. We carried out two carefully controlled allergen challenges with the same allergen dose within 4 to 6 weeks, at least 3 weeks apart, in each subject. On each study day, a bronchial challenge with methacholine was performed before and at different intervals after LAR. We found that EAR (maximal % fall in FEV1 within the 1st hour) measured on two different days was highly reproducible (37.8% +/- 8.9 and 38.7% +/- 12.1; CR: 12.1; Ri: 0.92; CoV: 15.1). Late asthmatic response (maximal % fall in FEV1 between 2nd and 12th hour) was also highly reproducible (47.5% +/- 12.4 and 46.1% +/- 13.4; CR: 10.1; Ri: 0.96; CoV: 10.1). All patients showed increases in nonspecific bronchial responsiveness to methacholine after LAR. Geometric mean PC20 M measured before the two allergen challenges was 0.609 mg/mL and 0.620 mg/mL, respectively. These values significantly decreased 24, 48, and 72 hours after LAR (after 1st allergen challenge: 0.086, 0.116, and 0.295 mg/mL; after 2nd allergen challenge: 0.075, 0.141, and 0.263 mg/mL). Ratio changes in PC20 methacholine (pre-allergen PC20 methacholine/lowest postallergen PC20) were highly reproducible (Ri: 0.95). We concluded that bronchial response to allergen challenge and the associated increase in responsiveness to methacholine are highly reproducible in well selected asthmatic subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Histochemical characteristics and degranulation of mast cells in epithelium and lamina propria of bronchial biopsies from asthmatic and normal subjects

We examined the staining characteristics and degranulation of mast cells in bronchial biopsy specimens taken by fiberoptic bronchoscopy from 13 stable asthmatic patients and eight normal nonsmoking subjects. Specimens were fixed in periodate-lysine-paraformaldehyde, embedded in glycol methacrylate, and stained with toluidine blue (2%) for 30 min (pH 2.7) and 7 days (pH 0.5). The number of mast cells in the epithelium and in the lamina propria was counted under light microscopy. In addition, the distribution of mast cells with different granule contents, arbitrarily defined as degranulated or partly degranulated and fully granulated, was estimated at the two levels. In asthmatic subjects, the number of mast cells in the epithelium after either staining method was significantly higher compared with that in control subjects. The number of mast cells in the lamina propria, but not in the epithelium, was significantly higher after 7 days compared with 30-min toluidine blue stain both in asthmatic (135.6/mm2 versus 74.8/mm2; p < 0.001) and control subjects (121.5/mm2 versus 71.5/mm2; p < 0.01). There was evidence of a progressive mast cell degranulation when moving toward the airway lumen in both groups. However, degranulation was more evident in asthmatic subjects. In both groups, granulated mast cells were absent in the epithelium, whereas in the lamina propria granulated mast cells were approximately one-third of total in asthmatic and two-thirds of total in normal subjects. These observations suggest that mast cells in human bronchial mucosa are heterogeneous with respect to histochemical characteristics. They provide evidence that degranulation of mast cells occurs in both asthmatic and normal subjects and that degranulation is greater in asthmatics.

Bronchial responsiveness to inhaled propranolol in asthmatic children and adults

Inhaled propranolol (P) was administered to a population which included asthmatic children (30 subjects) and adults (43 subjects): 1) to investigate the determinants of induced bronchial response; 2) to examine the relationship with treatment requirements; 3) to determine the relationship with responsiveness to methacholine (M) and ultrasonically nebulized distilled water (UNDW) (50 subjects); and 4) to establish the short-term repeatability of bronchial response to propranolol compared with methacholine (22 subjects). Bronchial response to propranolol and methacholine was expressed as the cumulative provocative dose (PD20 in mumol) and responsiveness to UNDW as the provocative output (PO20 in ml.min-1) producing a 20% fall in forced expiratory volume in one second (FEV1). Response to propranolol was significantly related to the degree of responsiveness to methacholine, but not to age, gender, presence of atopy, age at asthma onset, or baseline FEV1. PD20P was measurable in all but three subjects. A significant difference in mean PD20M but not in PD20P was found between subjects requiring more anti-asthmatic treatments compared to those without therapy. The difference between geometric mean PD20P and geometric mean PD20M was 14.1. PO20UNDW was measurable in only 21 out of 50 subjects. Both PD20P and PD20M were significantly lower in responders to UNDW than in nonresponders. Reproducibility of PD20P was comparable to that of PD20M (coefficients of repeatability: 1.17 and 1.09). We conclude that bronchial responsiveness to propranolol is safely measurable in most children and adults with asthma. Repeatability of bronchial response to propranolol is comparable to that of methacholine. Moreover, responsiveness to propranolol is not a predictor of treatment requirement.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchial responsiveness to inhaled propranolol in asthmatic children and adults

Inhaled propranolol (P) was administered to a population which included asthmatic children (30 subjects) and adults (43 subjects): 1) to investigate the determinants of induced bronchial response; 2) to examine the relationship with treatment requirements; 3) to determine the relationship with responsiveness to methacholine (M) and ultrasonically nebulized distilled water (UNDW) (50 subjects); and 4) to establish the short-term repeatability of bronchial response to propranolol compared with methacholine (22 subjects). Bronchial response to propranolol and methacholine was expressed as the cumulative provocative dose (PD20 in mumol) and responsiveness to UNDW as the provocative output (PO20 in ml.min-1) producing a 20% fall in forced expiratory volume in one second (FEV1). Response to propranolol was significantly related to the degree of responsiveness to methacholine, but not to age, gender, presence of atopy, age at asthma onset, or baseline FEV1. PD20P was measurable in all but three subjects. A significant difference in mean PD20M but not in PD20P was found between subjects requiring more anti-asthmatic treatments compared to those without therapy. The difference between geometric mean PD20P and geometric mean PD20M was 14.1. PO20UNDW was measurable in only 21 out of 50 subjects. Both PD20P and PD20M were significantly lower in responders to UNDW than in nonresponders. Reproducibility of PD20P was comparable to that of PD20M (coefficients of repeatability: 1.17 and 1.09). We conclude that bronchial responsiveness to propranolol is safely measurable in most children and adults with asthma. Repeatability of bronchial response to propranolol is comparable to that of methacholine. Moreover, responsiveness to propranolol is not a predictor of treatment requirement.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of inhaled disodium cromoglycate and nedocromil sodium on propranolol-induced bronchoconstriction

We conducted a randomized, double-blind, placebo-controlled study on the effect of disodium cromoglycate (DSCG) and nedocromil sodium (NED) on propranolol-induced bronchoconstriction (PIB) in 12 asthmatic subjects 10 to 53 years of age. Placebo (saline solution) and active drugs (10 mg) were aerosolized 30 minutes before bronchoprovocation with inhaled propranolol. Bronchial response to propranolol was expressed as the cumulative dose provoking a 20% fall in FEV1 (PD20P) and given in mumol. Reproducibility of PD20P was estimated before and after the days of study. PD20P varied within two doubling doses. Disodium cromoglycate and NED had no significant effect on baseline lung function. Although, geometric mean PD20P values (+/- GSEM) recorded after DSCG (7.24 mumol +/- 1.31) and after NED (9.22 mumol +/- 1.26) were higher than values recorded after placebo (6.55 mumol +/- 1.31), these differences were not statistically significant. A greater than 2-fold increase in PD20P was noted after NED in three subjects and in one subject after DSCG. We conclude that both DSCG and NED only modestly alter PIB, with some between subject differences.

Bronchial inflammation in mite-sensitive asthmatic subjects after 5 years of specific immunotherapy

We examined the pattern and degree of the inflammatory process in bronchial biopsy specimens taken by fiberoptic bronchoscopy in eight asthmatic subjects (two women aged 19-38 years) after 5 years of specific immunotherapy (SIT) to mite extracts (SIT group). At the time of study, they received a maintenance dose of mite-extracts (last subcutaneous administration 3 weeks before bronchoscopy). Results were compared with those found in eight matched mite-sensitive subjects with stable asthma (two women aged 19-36 years; non-SIT group) and in eight healthy individuals (four women aged 22-29 years; control group). Bronchial biopsy specimens were fixed in periodate-lysine-paraformaldehyde, embedded in glycol methacrylate, and stained with hematoxylin-eosin and 2% toluidine blue. Number of eosinophils, mast cells, and total nucleated cells were counted separately in the epithelium and lamina propria by light microscopy and expressed as cells/high power field. Within the epithelium, eosinophil and mast cell counts in SIT and non-SIT groups were significantly higher compared to controls, whereas total cell counts were not statistically different. Within the lamina propria, total cell count in SIT and non-SIT groups was significantly higher compared with the control group, whereas mast cells were similar. The number of eosinophils in both SIT and non-SIT groups was higher compared with controls; however this reached statistical significance only in SIT-groups. Comparison between the two groups of asthmatics did not show any significant difference for any cell counts.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of inhaled furosemide and torasemide on bronchial response to ultrasonically nebulized distilled water in asthmatic subjects

Inhaled furosemide has been shown to reduce the bronchoconstriction induced by several indirect stimuli, including ultrasonically nebulized distilled water (UNDW). Because the protective effect could be due to the inhibition of the Na(+)-2Cl(-)-K+ cotransport system of bronchial epithelium, we have compared the protective effect of inhaled furosemide with that of inhaled torasemide, a new and more potent loop diuretic, on UNDW-induced bronchoconstriction in a group of 12 asthmatic subjects. UNDW challenge was performed by constructing a stimulus-response curve with five increasing volume outputs of distilled water (from 0.5 to 5.2 ml/min) and the bronchial response expressed as the provocative output causing a 20% fall in FEV1 (PO20UNDW). On different days, each subject inhaled an equal dose (28 mg) of furosemide and torasemide in a randomized, double-blind, placebo-controlled study 5 min prior to an UNDW challenge. Furosemide and torasemide had no significant effect on resting lung function. The geometric mean value of PO20UNDW measured after placebo was 1.73 ml/min. This was significantly lower than that recorded after furosemide (4.25 ml/min; p < 0.025), but not after torasemide (3.05 ml/min; p = 0.07). Inhaled furosemide totally blocked bronchial response to UNDW in five subjects. In two of five subjects the response was also blocked by inhaled torasemide. A remarkable increase in diuresis was noted only after torasemide in most subjects. We conclude that inhaled furosemide has a better protective effect than does inhaled torasemide against UNDW-induced bronchoconstriction. However, the protective effect of furosemide is variable, with some asthmatic patients showing no change in bronchial response to UNDW.(ABSTRACT TRUNCATED AT 250 WORDS)

Lung function and bronchial responsiveness after bronchoalveolar lavage and bronchial biopsy performed without premedication in stable asthmatic subjects

We evaluated tolerance, safety, and effects on lung function and bronchial responsiveness of BAL (4 x 50 ml) combined with BB (three to five specimens) performed without premedication in 13 mild and stable asthmatics and eight healthy volunteers. All subjects tolerated bronchoscopy procedures well and without serious side effects. During procedures, no supplemental oxygen was administered and no ECG abnormalities were noted. The PEFR was measured before and immediately after bronchoscopy and at 5-min intervals up until recovery. The maximal percentage fall in PEFR after bronchoscopy was significantly greater in asthmatics (23.1 +/- 13.9 percent) compared to normal subjects (7.8 +/- 8.2 percent, p less than 0.01). Changes in PEFR returned to baseline values within 120 min in all asthmatics. The tcPO2 was recorded at baseline, during and after bronchoscopy. In both groups, a significant change in tcPO2 was measured during the infusion of BAL aliquots, and persisted throughout the procedure. A significant difference in asthmatics compared to healthy subjects was evident during BB and at the end of the procedure (p less than 0.05). In asthmatics, M challenge was performed on three different days over a three-week period prior to bronchoscopy, and was repeated at intervals of 2, 6, and 24 h following procedure. The PC20 M values measured before bronchoscopy were found to have a very high reproducibility (intraclass correlation coefficient = 0.93). The PC20 values measured during experiment times after bronchoscopy were not significantly different from baseline values. These data demonstrate that in mild and stable asthmatics, BAL combined with BB can be safely performed following administration of only local anesthesia. In carefully selected asthmatic subjects, transient bronchoconstriction and a lowering of oxygen tension can be induced by BAL and BB, whereas changes in bronchial responsiveness are more unlikely to occur.

Evaluation of a new method for assessing arterial oxygen pressure, avoiding arterial blood collection

Arterial computed PO2 (PO2 com) was computed from SaO2 ear and finger capillary pH using equations of Severinghaus and Ellis, and compared with measured arterial PaO2 in 100 patients with chronic obstructive pulmonary disease (76 men, aged 42 to 82 yr). SaO2 ear ranged from 73 to 98%. There was no significant difference between SaO2 ear and SaO2 com (calculated from PaO2 and arterial pH), nor between arterial pH and pHc (capillary blood). Mean directly measured finger capillary oxygen tension, PcO2, was lower than PaO2 by 10.1 mm Hg +/- 5.4 SD. Mean bias of (PaO2-PO2 com) was -0.22 mm Hg +/- 2.6 SD. When subdivided by range, bias, and SD of mean bias of (PaO2-PO2 com) were -0.47 mm Hg +/- 2.5 with SaO2 ear less than 95% and 0.1 mm Hg +/- 2.9 with SaO2 ear greater than 95%. We conclude that PaO2 may be reliably computed from SaO2 ear and capillary pH when SaO2 ear is less than 98%.

Correlation between cell content of bronchoalveolar lavage (BAL) and histologic findings in asthma

We have recently examined the relationship between cell content of bronchoalveolar lavage (BAL) fluid and lung histology in a group of 13 asthmatic subjects during clinical remission. Inflammatory cells in BAL appeared to reflect the severity of the overall inflammatory process of the bronchial mucosa. In the present report we examined whether in asthma the presence of a thickened basement membrane is associated with inflammation of the bronchial mucosa. There was a significantly higher number of inflammatory cells (p less than 0.01) and eosinophils (p less than 0.005) in the submucosa of subjects showing a thickened basement membrane (greater than 7 microns) compared to those having normal basement membrane (less than or equal to 7 microns). These findings seem to support the hypothesis that the degree of thickening of basement membrane in asthma is related to mucosal inflammation.

Inflammatory markers in bronchoalveolar lavage and in bronchial biopsy in asthma during remission

Bronchoalveolar lavage and BB were performed in 13 asthmatic and six healthy subjects to characterize cellular markers of inflammation in BAL and BB; to compare cellular profile of BAL with cell infiltration in BB; to examine the relationship between bronchial responsiveness and markers of inflammation in BAL and BB. Eosinophils and mast cells were increased in BAL in asthmatic subjects; eosinophils were positively correlated with neutrophils and mast cells. Epithelial shedding was present in nine asthmatic and five control subjects. Intraepithelial cells and cells in submucosa were increased in asthmatic subjects. Eosinophils and intraepithelial mast cells were higher. Thickened basement membrane was associated with more marked cell infiltration in submucosa. Ciliated cells in BAL relate to intraepithelial cells; cells in BAL broadly reflect cell infiltration of submucosa. In the asthmatic group, the degree of bronchial responsiveness correlated with ciliated cells in BAL and with intra-epithelial cells in BB. Marked airway inflammation is associated with stable asthma; inflammatory changes within bronchial epithelium may be linked to the development of bronchial hyperresponsiveness.

Snoring in children: association with respiratory symptoms and passive smoking

OBJECTIVE

To investigate the relation between snoring and various respiratory symptoms and passive parental smoking.

DESIGN

Data were collected by questionnaire.

SETTING

Primary schools in Guardiagrele and Francavilla in the Abruzzi region in central Italy.

SUBJECTS

1615 Children aged 6-13 years were categorised according to whether they snored often; occasionally apart from with colds; only with colds; or never.

RESULTS

118 Children were habitual snorers and 137 were reported to snore apart from when they had colds. Never snorers (n = 822) were significantly older than children in other categories. Snoring was significantly associated with rhinitis, production of cough and sputum, previous tonsillectomy, and passive parental smoking. Of the habitual snorers, 82 were exposed to passive smoking. The prevalence of habitual snoring increased significantly with the number of cigarettes smoked by parents (from 5.5% in never smoking [corrected] households to 8.8% in heavy smoking households).

CONCLUSIONS

Snoring is quite common in children. The dose-effect relation of smoking and snoring shown in this study adds weight to a further adverse effect of parental smoking on children's health.