A case of severe allergic eosinophilic asthma with nasal polyposis in a patient affected by Birt-Hogg-Dubé syndrome successfully treated with benralizumab.

SUMMARY: Birt-Hogg-Dubé (BHD) syndrome is a rare genetic pathology characterized by cutaneous fibrofolliculomas, pulmonary cysts and kidney tumours. Severe asthma is the most serious form of asthma that does not respond to standard treatments. We present the case of a 68 years-old male patient who had frequent respiratory tract infections, shortness of breath and decline in lung function, nasal polyposis and hypertrophy of the nasal turbinates, for this reason was treated as a severe asthmatic patient for several years with ICS + LABA and high doses of OCS. When we tried to reduce OCS the patient had worsening of the symptoms, we requested a HRTC scan that showed presence of several cysts spread ubiquitously. The patient had a family history of pneumothorax, for this reason we requested a genetic test that resulted in a heterozygous point mutation on exon 12 (c.1429 C > T) of FLCN gene. Despite the diagnosis of BHD syndrome, the patient's clinical condition kept on suggesting an underlying severe asthma and the blood tests we requested pointed out a high percentage of eosinophils, for this reason we opted for the administration of benralizumab that resulted in an excellent asthma control and increased quality of life.

A New SERPINA-1 Missense Mutation Associated with Alpha-1 Antitrypsin Deficiency and Bronchiectasis.

Alpha-1-antitrypsin deficiency (AATD) is a genetic condition caused by SERPINA1 mutations, which culminates into lower protease inhibitor activity in the serum and predisposes to emphysema. Clinical manifestations of AATD are often associated to ZZ (p.Glu342Lys) and SZ (p.Glu264Val) genotypes and less frequently to rare deficiency or null alleles in heterozygous and homozygous states. We report a case of a 52-year-old woman with bronchiectasis without other potential causes other than an electrophoresis that showed a decrease of alpha-1 globin band and AAT levels below the normal value (78 mg/dl; v.n. 90-200 mg/dl). No S or Z mutation was identified, but sequencing analysis found a novel missense variant Ile74Asn (c.221T > A) in heterozygous state on an M3 allele (Glu400Asp) in the exon 2 of the SERPINA-1gene, probably leading to a dysfunctional protein. This mutation has never been previously identified, and it is interesting to note the association with bronchiectasis in the absence of emphysema.

Exhaled breath temperature measurement: influence of circadian rhythm.

Exhaled breath temperature (EBT) is an expression of airway inflammation, an event that drives several lung diseases. The measurement of the exhaled breath temperature has recently been proposed as a popular tool in the diagnosis and monitoring of inflammatory lung diseases due to the fact that it is a non-invasive method. The influence of external factors on EBT, its reproducibility, and its sensitivity to treatment have already been explored. However, to reach clinical practice, EBT requires a complete validation that is still lacking. The aim of this study was to analyse the possible influence of an important internal variable, i.e the circadian rhythm on EBT values in a group of 24 healthy adult volunteers. We repeated measurement of EBT at different hours of the day: 8.00 AM, 12.00 AM, 4.00 PM, 8.00 PM and analysed the correlation with axillary temperature measurement at these times. The EBT resulted significantly different during daily measurements (8.00 AM vs 12.00 AM vs 4.00 PM vs 8.00 PM: 28.01±1.64°C vs 28.8±1.82°C vs 29.34±1.79°C vs 28.06±1.34°C). The highest EBT was reported at 4.00 PM and the lowest at 8.00 AM. For the first time we found an influence of the circadian rhythm on EBT. These data support the validation of the EBT necessary for its promotion in clinical practice.

How strong is the association between IPF and lung cancer? An answer from airway's DNA.

Idiopathic pulmonary fibrosis is a chronic progressive disease of lung interstitium of unknown etiology with poor prognosis. In patients with IPF, the incidence of lung cancer is much higher than that in the general population. The identification of noninvasive biomarkers for early diagnosis of IPF is of great relevance in consideration of the management of these patients. Among the noninvasive omic markers, an increasing interest has been directed toward the study of genetic alterations of microsatellites (MAs) in exhaled breath condensate (EBC). The aim of this preliminary study was to investigate the MAs, located in chromosomal regions 8p21.3-q11.1 and 17q11.2-q21, that harbor tumor suppressor genes, in EBC and in the paired whole blood (WB) of IPF patients. Eleven IPF patients were compared with 10 healthy control subjects. All subjects underwent collection of the EBC and WB. The EBC was collected using a condenser. Four microsatellite markers (THRA1, D17S579, D17S250 and D8S137) were used for the analysis of MAs. The EBC-DNA and WB-DNA were amplified by PCR; PCR products were analyzed using the ABI Prism 310 DNA. Microsatellite alterations were found in 58.82 % of EBC-DNA and 12.50 % of WB-DNA in patients with IPF (p < 0.01). None of the healthy subjects exhibited MAs in the studied markers. Our findings suggest that these genetic alterations, studied in EBC, may play an important role in the complex genetic basis of IPF. Since these MAs are frequently detected in cancer, they might explain the higher relative risk of tumorigenesis in this disease.

Effects of omalizumab in severe asthmatics across ages: A real life Italian experience.

BACKGROUND: This retrospective study aimed at evaluating long-term effects of Omalizumab in elderly asthmatics in a real-life setting. METHODS: 105 consecutive severe asthmatics (GINA step 4-5; mean FEV1% predicted:66 ± 15.7) treated with Omalizumab for at least 1 year (treatment mean duration 35.1 ± 21.7 months) were divided into 3 groups according to their age at Omalizumab treatment onset: 18-39, 40-64 and ≥ 65 years. RESULTS: Comorbidities, number of overweight/obese subjects and patients with late-onset asthma were more frequent among older people. A similar reduction of inhaled corticosteroids dosage and SABA on-demand therapy was observed in all groups during Omalizumab treatment; a similar FEV1 increased was also observed. Asthma Control Test (ACT) improved significantly (p < 0.001) in the three groups, increasing from 15 [IQR:12-18] to 24 [IQR:22-25] in younger subjects, from 14 [IQR:10-16] to 21 [IQR:20-23] in the 40-64-year-group and from 15 [IQR:12-16] to 20 [IQR:18-22] in elderly patients where improvement was lower (p = 0.039) compared to younger people. Asthma exacerbations decreased significantly after Omalizumab but the percentage of exacerbation-free patients was higher in younger people (76.9%) compared to middle aged patients (49.2%) and the elderly (29%) (p = 0.049). After Omalizumab treatment, the risk for exacerbations was lower in subjects aged 40-64 (OR = 0.284 [CI95% = 0.098-0.826], p = 0.021) and 18-39 (OR = 0.133 [CI95% = 0.026-0.678], p = 0.015), compared to elderly asthmatics. Also, a significantly reduced ACT improvement (ß = -1.070; p = 0.046) passing from each age class was observed. CONCLUSION: Omalizumab improves all asthma outcomes independently of age, although the magnitude of the effects observed in the elderly seems to be lower than in the other age groups.

Study of mitochondrial DNA alteration in the exhaled breath condensate of patients affected by obstructive lung diseases.

Mitochondrial DNA (MtDNA) has been studied as an expression of oxidative stress in asthma, COPD, lung cancer and obstructive sleep apnea, but it has been mainly investigated systemically, although the pathogenetic mechanisms begin in the airways and only later progress to systemic circulation. The aim of this study was to investigate the MtDNA alterations in the exhaled breath condensate (EBC) of patients with asthma, COPD and asthma-COPD overlap syndrome (ACOS). In order to analyze better what happens to mitochondria, both locally and systemically, we compared MtDNA/nDNA in blood and EBC of paired patients. Thirteen (13) COPD patients, 14 asthmatics, 23 ACOS (10 according to Spanish guidelines, 13 in line with GINA guidelines) and 12 healthy subjects were enrolled. Patients underwent clinical and functional diagnostic tests as foreseen by the guidelines. They underwent blood and EBC collection. Content of MtDNA and nuclear DNA (nDNA) was measured in the blood cells and EBC of patients by Real Time PCR. The ratio between MtDNA/nDNA was calculated. For the first time we were able to detect MtDNA/nDNA in the EBC. We found higher exhaled MtDNA/nDNA in COPD, asthmatic and ACOS patients respectively compared to healthy subjects (21.9 ± 4.9 versus 6.51 ± 0.21, p < 0.05; 7.9 ± 2.5 versus 6.51 ± 0.21, p = 0.06; 18.3 ± 3.4 versus 6.51 ± 0.21, p < 0.05). The level of exhaled MtDNA/nDNA was positively correlated with the plasmatic one. The levels of MtDNA/nDNA in the EBC, as expression of oxidative stress, are increased in COPD, asthmatic and ACOS patients compared to healthy subjects. These are preliminary results in a small number of well characterized patients that requires confirmation on a larger population. We support new studies directed toward the analysis of exhaled MtDNA/nDNA as a new exhaled non-invasive marker in other inflammatory/oxidative airways diseases.

Analysis of mitochondrial DNA alteration in new phenotype ACOS.

BACKGROUND: Mitochondria contain their own DNA (MtDNA) that is very sensitive to oxidative stress and as a consequence could be damaged in quantity. Oxidative stress is largely recognized to play a key role in the pathogenesis of asthma and COPD and might have a role in the new intermediate phenotype ACOS (asthma-COPD overlap syndrome). The aim of this study was to investigate MtDNA alterations, as an expression of mitochondrial dysfunction, in ACOS and to verify whether they might help in the identification of this new phenotype and in its differentiation from asthma and COPD. METHODS: Ten (10) ACOS according to Spanish guidelines, 13 ACOS according to GINA guidelines, 13 COPD, 14 asthmatic patients and ten normal subjects were enrolled. They further underwent a blood, induced sputum and exhaled nitric oxide collection. Content of MtDNA and nuclear DNA (nDNA) were measured in the blood cells of patients by Real Time PCR. RESULTS: ACOS patients showed an increase of MtDNA/nDNA ratio. Dividing ACOS according to guidelines, those from the Spanish showed a higher value of MtDNA/nDNA compared to those from GINA/GOLD (92.69 ± 7.31 vs 80.68 ± 4.16). Spanish ACOS presented MtDNA/nDNA ratio closer to COPD than asthma. MtDNA was higher in asthmatic, COPD, GINA and Spanish ACOS patients compared to healthy subjects (73.30 ± 4.47-137.0 ± 19.45-80.68 ± 4.16-92.69 ± 7.31 vs 65.97 ± 20.56). CONCLUSION: We found an increase of MtDNA/nDNA ratio in ACOS subjects that led us to conclude that there is presence of mitochondrial dysfunction in this disease, that makes it closer to COPD than to asthma. Although the MtDNA/nDNA ratio results are a useful marker for differential diagnosis from asthma, COPD and ACOS, further studies are needed to confirm the potentiality of MtDNA/nDNA ratio and to a better characterization of ACOS.

Fluticasone propionate/formoterol: a fixed-combination therapy with flexible dosage.

International guidelines describe asthma control as the main outcome of asthma management. Prevention of symptoms, improved quality of life, and reduction of exacerbations are the main components, consequently decreasing health care costs. However, many of these objectives remain unmet in real life: several surveys show that a large proportion of asthmatic patients are not well controlled despite the efficacy of current available treatment. Several randomized controlled clinical trials indicate that combining inhaled corticosteroids and long-acting ß2-agonists, by means of a single inhaler, greatly improves the management of the disease. The results of 9 multicenter phase III clinical studies demonstrate that the fixed combination of fluticasone propionate/formoterol in a single inhaler is effective in terms of lung function and symptom control. These studies highlight the dose flexibility, safety and tolerability of this new inhaled combination. These characteristics meet the recommendations of international guidelines, and the preferences of respiratory physicians who identified these aspects as critical components of a successful asthma therapy. Combination of fluticasone propionate/formoterol in a single inhaler provides potent anti-inflammatory activity of fluticasone propionate and rapid onset of action of the ß2-agonist formoterol making this association a viable treatment option both in terms of effectiveness and compliance.

Effect of endothelin inhibition on lung fibroblasts on patients with systemic sclerosis.

AIM: The aim of the study was to investigate the effect of selective ETRA Sitaxsentan on viability and differentiation into myofibroblasts of lung fibroblasts derived from SSc-ILD patients and the ability of this drug to modify the lung fibroblast synthesis of VEGF, type I collagen and fibronectin. METHODS: Primary human lung fibroblast cultures were obtained from BAL of SSc-ILD patients. Cell cultures were exposed for 48 h to crescent concentrations of Sitaxsentan (10 -6M to 10 -4M). In these experimental conditions we evaluated cell viability through crystal violet staining, the production and mRNA expression of VEGF, fibronectin and type I collagen respectively through ELISA and real-Time PCR. Further, we detected alpha-Smooth Muscle Actin (α-SMA) through immunocytochemical assay. RESULTS: The lowest concentration of sitaxsentan (10-6M) did not affect fibroblasts viability; conversely at higher concentrations, sitaxsentan induced a significant inhibition of cell viability. Synthesis and mRNA expression of VEGF, type 1 collagen and fibronectin were significantly reduced in treated lung fibroblasts compared to the untreated ones, in a dose-dependent manner. At higher concentrations, Sitaxsentan reduced the expression of α-SMA. CONCLUSION: The results of this study show that sitaxentan is able in vitro to reduce both cell viability than production of VEGF and extra-cellular matrix components in SSc lung fibroblasts, confirming the anti-fibrotic potential of ETRA in SSc. The decreased expression of α-SMA in treated cells indicate that sitaxsentan may inhibit the fibroblast differentiation toward a myo-fibroblast phenotype and further support the hypothesis that the selective ETRAs may be beneficial in patients with SSc-ILD as anti fibrotic agents.

Daytime PaO2 in OSAS, COPD and the combination of the two (overlap syndrome).

BACKGROUND: OSAS and COPD are often associated with day-time hypoxemia. Overlap Syndrome (OS), the association between both diseases, increases the risk of day-time hypoxemia. The aim of this study was to investigate the mechanisms which could justify the low oxygen level and the effect of CPAP. METHODS: We performed a retrospective analysis in all patients referred to our institutes for suspected OSAS and who also underwent spirometry and blood gas analysis during our evaluation. Thus, 720 patients were selected. According to pulmonary function test parameters they were divided into 3 groups: OSAS (N = 466,65%); OS (N = 168,23%) and COPD (N = 86,12%). In order to evaluate the differences between the three groups, ANOVA analyses were carried out, whereas a multivariate analysis was performed in order to evaluate which factors determine the diurnal PaO(2). In 90 patients we also have the data on blood gas analysis after one year of CPAP treatment, so we evaluate the PaO(2) improvement in accordance with compliance to treatment in these patient subgroups. RESULTS: The OS group showed a lower level of daytime PaO(2) compared with OSAS patients and T90 was higher in OS compared with OSAS. A multivariate analysis showed that in the OS diurnal PaO(2) correlated with age (ß = -0.20) and moreover with FEV(1) (ß = 0.31) and T90 (ß = 0.37), while in the OSAS a correlation was found with FEV(1) (ß = -0.11) and mostly with BMI (ß = 0.25), age and T90. In all patients with good compliance to CPAP day-time PaO(2) improved. CONCLUSIONS: Our data suggest that day-time hypoxemia in OSA patients is largely determined by the increase of body weight and severity of nocturnal hypoxia. However, CPAP therapy has been shown to improve daytime PaO(2) values both in OSAS and in OS.

HPV in exhaled breath condensate of lung cancer patients.

BACKGROUND: A recent intriguing carcinogenetic hypothesis for lung cancer foresees its viral aetiology. The human papilloma virus (HPV) is the main virus actually recognised in the pathogenesis of lung cancer. The aim of this study was to investigate, for the first time to our knowledge, the presence of HPV in the exhaled breath condensate (EBC) of lung cancer patients. MATERIALS AND METHOD: We enrolled 89 patients affected by lung cancer and 68 controls. HPV infections were investigated in their EBC, paired bronchial brushing and neoplastic lung tissue through genotyping. RESULTS: We were able to detect HPV in the EBC, bronchial brushing and neoplastic lung tissue. We described the presence of an HPV infection in 16.4% of the subjects affected by non-small cell lung cancer, but in none of the controls. HPV 16 and 31 turned out to be the most widespread genotypes. The HPV positivity in airways as well as in the smoking habit was seen to independently increase the individual's susceptibility to developing lung cancer. CONCLUSION: When summing up, we demonstrated the possibility to identify an HPV infection in the EBC of lung cancer patients; further, we supported the notion that the EBC is a suitable tool to study airway colonisation. That being said, although further studies are needed to confirm our results, we retain the study of HPV in EBC to be very interesting in terms of future programmes involving lung-cancer screening.

Effect of CPAP-therapy on bronchial and nasal inflammation in patients affected by obstructive sleep apnea syndrome.

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) has been shown to be associated to upper and lower airways inflammation. Continuous positive airway pressure (CPAP) is the elective treatment of OSAS. The aim of the present study was to assess the effect of CPAP-therapy on airway and nasal inflammation. METHODS: In 13 non-smoking subjects affected by untreated OSAS and in 11 non-smoking normal volunteers, airway inflammation was detected by analyses of the induced sputum. In the OSAS group measurements were repeated after 1, 10 and 60 days of the appropriate CPAP treatment. In addition, in 12 subjects of the OSAS group, nasal inflammation was detected by the analysis of induced nasal secretions at baseline, and after 1, 10 and 60 days of CPAP treatment. RESULTS: OSAS patients, compared to normal controls, showed at baseline a higher percentage of neutrophils and a lower percentage of macrophages in the induced sputum. One, 10 and 60 days of appropriate CPAP-therapy did not change the cellular profile of the induced sputum. In addition, in the OSAS patients, the high neutrophilic nasal inflammation present under baseline conditions was not significantly modified by CPAP-therapy. Finally, no patients developed airway hyper-responsiveness after CPAP therapy. CONCLUSIONS: In OSAS subjects, the appropriate CPAP-therapy, while correcting the oxygen desaturation, does not modify the bronchial and nasal inflammatory profile.

Repeated virus identification in the airways of patients with mild and severe asthma during prospective follow-up.

BACKGROUND: Respiratory viruses may persist in the airways of asthmatics between episodes of clinical worsening. We hypothesized that patients with clinically stable, severe asthma exhibit increased and more prolonged viral presence in the airways as compared to mild asthmatics and healthy controls. METHODS: Thirty-five subjects (no cold symptoms >4 weeks) entered a 12-week prospective study using three groups: clinically stable mild asthma (GINA 2) (n = 12, age 34.1 ± 13.4 year), severe asthma (GINA 4) (n = 12, age 49.3 ± 14.8 year) and healthy controls (n = 11, age 37.9 ± 14.2 year). All subjects underwent spirometry and completed a written questionnaire on asthma symptoms at baseline. Nasal and throat swabs, induced sputum samples, exhaled breath condensate and gelatine-filtered expired air were analysed at 0, 6 and 12 weeks by a multiplex real-time PCR assay for 14 respiratory viruses using adequate positive and negative controls. RESULTS: Thirty-two of 525 patient assessments (6%) showed a virus-positive sample. Among the 14 respiratory viruses examined, HRV, adenovirus, respiratory syncytial virus, parainfluenza 3&4, human bocavirus, influenza B and coronavirus were detected. When combining all sampling methods, on average 18% of controls and 30% of mild and severe asthmatics were virus positive, which was not different between the groups (P = 0.34). The longitudinal data showed a changing rather than persistent viral presence over time. CONCLUSION: Patients with clinically stable asthma and healthy controls have similar detection rates of respiratory viruses in samples from nasopharynx, sputum and exhaled air. This indicates that viral presence in the airways of stable (severe) asthmatics varies over time rather than being persistent.

Menopausal asthma: a new biological phenotype?

BACKGROUND: Female hormones play an important role in women's lung health, especially in asthma pathophysiology. Although a growing interest has recently been aroused in asthma related to short-term reproductive states, menopausal asthma has been little studied in the past. The aim of the present study was to explore airway inflammation in menopausal asthmatic women in a noninvasive manner. METHODS: Forty consecutive women with menopausal asthma, 35 consecutive women with premenopausal asthma and 30 age-matched healthy controls were enrolled in the study. Urinary LTE-4, induced sputum inflammatory cells, and exhaled LTE-4, IL-6, pH, and NO levels were measured in all the subjects enrolled. RESULTS: Women with menopausal asthma showed decreased estradiol concentrations, high sputum neutrophils, and exhaled IL-6. Women with premenopausal asthma presented instead an essentially eosinophilic inflammatory pattern. Higher urine and breath condensate LTE-4 concentrations were found in premenopausal and menopausal asthma compared to controls. CONCLUSION: Our results substantiate the existence of a new biological phenotype of menopausal asthma that is mainly characterized by neutrophilic airways inflammation and shares several characteristics of the severe asthma phenotype.

Airways oxidative stress, lung function and cognitive impairment in aging.

BACKGROUND: An altered balance of oxidants/antioxidants is one of the pathological mechanisms of many age-dependent disorders. We aimed to investigate the age-related airways oxidative stress, using non invasive, safe and repeatable techniques; to evaluate the correspondence between systemic and local oxidative stress in healthy subjects of different age ranges; to analyse the correlation between systemic and local oxidative stress with lung function and with cognitive impairment. METHODS: Thirty consecutive healthy high school graduated subjects (8 M, 22 F), divided in three ranges of age (< 35; between 35 and 60; > 60 years) were enrolled. All subjects underwent oxygen free radicals and exhaled nitric oxide measurement (by the diacron reactive oxygen metabolites test and by a rapid-response chemiluminescence nitric oxide analyzer), lung function tests, and cognitive impairment scales (Mini Mental State Examination and Geriatric Depression Scale). RESULTS: A significant increase of oxygen free radicals, exhaled nitric oxide, and Geriatric Depression Scale score and a significant decrease of forced expiratory volume in 1 second and forced expiratory vital capacity from younger to older subjects were identified. Moreover, the significant positive correlation between oxygen free radicals and exhaled nitric oxide, and between oxygen free radicals and exhaled nitric oxide with Geriatric Depression Scale score were found. The significant negative correlation between forced expiratory volume in 1 second and oxygen free radicals or exhaled nitric oxide was also demonstrated. CONCLUSIONS: Our data supports the role of progressive local oxidative stress in damaging the lung function and in inducing depression symptoms.

The role of obstructive sleep apnea syndrome and obesity in determining leptin in the exhaled breath condensate.

Leptin plays a key role in obstructive sleep apnea syndrome (OSAS). Leptin production in human airways has been previously evaluated by measuring leptin concentration in the exhaled breath condensate and in the induced sputum. The aim was to study leptin expression in the cells of induced sputum and in exhaled breath condensate of subjects with OSAS. Moreover, leptin concentrations in the blood were measured in the same groups of subjects. We enrolled four groups of patients: (1) obese patients with OSAS (OO); (2) non-obese patients with OSAS (NOO); (3) obese patients without OSAS (ONO); and (4) non-obese subjects without OSAS (C). Leptin expression was evaluated by immunocytochemistry in the sputum cells of the enrolled subjects. The concentrations of leptin in the exhaled breath condensate and plasma were measured by using a specific enzyme immunoassay. Leptin protein expression and the percentage of macrophages and neutrophils expressing leptin were higher in the induced sputum of OO, NOO and ONO patients than in C. Leptin concentrations in the exhaled breath condensate were significantly higher in OO patients (5.12 (3.8-6.6) ng ml(-1)) than in NOO (4.1 (3.9-5.2) ng ml(-1)) and ONO (4.2 (3.6-5.0) ng ml(-1)) patients. The concentration of leptin in plasma was significantly more elevated in OO (36 (24-65.9) ng ml(-1)) than in NOO (30.2 (12.4-51.4) ng ml(-1)), whereas it was not significantly different in ONO patients. This study showed that leptin in sputum and in the exhaled breath condensate is higher in obese patients with OSAS than in obese subjects without OSAS. Moreover, different mechanisms for determining leptin concentrations in the exhaled breath condensate and the blood are suggested.

Exhaled NO and iNOS expression in sputum cells of healthy, obese and OSA subjects.

BACKGROUND: Obstructive sleep apnoea (OSA) is associated with airways inflammation; a key role in this regard seems to be played by nitric oxide (NO). The aim of this study was to measure exhaled NO and expression of its enzyme, the inducible nitric oxide synthase (iNOS) in cells of induced sputum in OSA patients and in obese subjects without sleep apnoea and to correlate these inflammatory markers with severity of OSA. METHODS: We enrolled 18 obese patients with OSA (10 men, age 48.2 +/- 8.4 years), 15 obese patients without OSA (eight men, age 52.8 +/- 11 years) and 10 healthy subjects (five men, age 42 +/- 4 years). Exhaled NO was measured using a chemiluminescence analyser; iNOS expression was measured in the sputum cells by immunocytochemistry. RESULTS: Exhaled NO resulted significantly increased in OSA and in obese patients (23.1 +/- 2.1 and 17.9 +/- 2.1 p.p.b.) than in healthy subjects (7.2 +/- 0.6 p.p.b.; P < 0.001). OSA and obese patients showed a higher percentage of neutrophils and a lower percentage of macrophages in the induced sputum compared to healthy subjects. In addition, OSA and obese patients showed higher iNOS expression in neutrophils and in macrophages with respect to healthy subjects. A positive correlation between exhaled NO, iNOS expression and AHI was observed. CONCLUSIONS: These data confirm the presence of airway inflammation in OSA and in obese patients, and suggest the possible role for NO and iNOS expression in neutrophils of the induced sputum as noninvasive markers to identify and monitor the airway inflammation in these subjects.