Obstructive Sleep Apnea in School-Aged Children Presented with Nocturnal Enuresis.

OBJECTIVES: We aimed to detect obstructive sleep apnea (OSA) among school-age children presented with nocturnal enuresis (NE) and to identify the possible risk factors for OSA in them. METHODS: Sixty-six children aged > 5-16 years presented with NE were enrolled in the study. Children with urinary tract anatomical abnormalities or infection, intellectual disabilities, genetic syndromes, psychological issues, and diabetes mellitus were excluded. They were clinically examined, scored using sleep clinical record score (SCR), and subjected for full-night polysomnogram (PSG). Children with obstructive apnea/hypopnea index (AHI) ≥ 2 episodes/hour (h) were considered as OSA. RESULTS: Fifty-four children (81.8% of the recruited children) aged 8.3 ± 2.8 years agreed to undergo PSG as 68.5% had OSA with median obstructive AHI of 6.1 (3.7-13.2) episodes/h, median oxygen saturation of 97% and nadir of 88%. Thirty-three percent were obese with significantly higher AHI [7.0 (3.7-12.4) vs. 2.4 (1.3-6.1) episodes/h; p = 0.023]. SCR score correlated significantly with AHI (r2 = 0.462, p = 0.001) with 91% sensitivity in detecting OSA ≥ 5 episodes/h. Nasal obstruction, adenoid/adult facial phenotype, and arched palate were associated with OSA (p < 0.05). CONCLUSION: NE is commonly associated with OSA especially in obese children. Nasal obstruction, abnormal facial phenotype, and high-arched palate were common risk factors.

Can myofunctional therapy increase tongue tone and reduce symptoms in children with sleep-disordered breathing?

PURPOSE: Data in the literature suggest that myofunctional therapy (MT) may be able to play a role in the treatment of children with sleep-disordered breathing (SDB). Our study investigated the effectiveness of MT in reducing respiratory symptoms in children with SDB by modifying tongue tone. METHODS: Polysomnographic recordings were performed at baseline to assess obstructive sleep apnea (OSA) severity in 54 children (mean age 7.1 ± 2.5 years, 29 male) with SDB. Patients were randomly assigned to either the MT or no-MT group. Myofunctional evaluation tests, an assessment of tongue strength, tongue peak pressure, and endurance using the Iowa Oral Performance Instrument (IOPI), and nocturnal pulse oximetry were performed before (T0) and after (T1) 2 months of treatment. RESULTS: MT reduced oral breathing (83.3 vs 16.6%, p < 0.0002) and lip hypotonia (78 vs 33.3%, p < 0.003), restored normal tongue resting position (5.6 vs 33.4%, p < 0.04), and significantly increased mean tongue strength (31.9 ± 10.8 vs 38.8 ± 8.3, p = 0.000), tongue peak pressure (34.2 ± 10.2 vs 38.1 ± 7.0, p = 0.000), and endurance (28.1 ± 8.9 vs 33.1 ± 8.7, p = 0.01) in children with SDB. Moreover, mean oxygen saturation increased (96.4 ± 0.6 vs 97.4 ± 0.7, p = 0.000) and the oxygen desaturation index decreased (5.9 ± 2.3 vs 3.6 ± 1.8, p = 0.001) after MT. CONCLUSIONS: Oropharyngeal exercises appear to effectively modify tongue tone, reduce SDB symptoms and oral breathing, and increase oxygen saturation, and may thus play a role in the treatment of SDB.

Exhaled nitric oxide and other exhaled biomarkers in bronchial challenge with exercise in asthmatic children: current knowledge.

The fractional concentration of exhaled nitric oxide (FENO), a known marker of atopic-eosinophilic inflammation, may be used as a surrogate to assess exercise-induced bronchoconstriction (EIB) in asthmatic children. The predictive value of baseline FENO for EIB appears to be influenced by several factors, including age, atopy, current therapy with corticosteroids and measurement technique. Nonetheless, FENO cut-off values appear to be able to rule out EIB. FENO levels decrease during EIB, apparently through neural mechanisms rather than by decreased airway-epithelial surface. Partition of FENO into proximal and peripheral contributions of the respiratory tract may improve our understanding on NO exchange during exercise and help to screen subjects prone to EIB. Other biomarkers of inflammation and oxidative stress contained in exhaled gases and exhaled breath condensate (EBC) may shed light on the pathophysiology of EIB. Exhaled breath temperature is a promising real-time measurement whose routine use for assessing EIB warrants further investigation.

Intestinal permeability in children with recurrent respiratory and gastrointestinal symptoms.

AIM: Increased intestinal permeability has been reported in asthmatic subjects as well as in patients with gastrointestinal disease, thus suggesting the involvement of all the mucosal immune system. We aimed to assess intestinal permeability according to recurrent respiratory and gastrointestinal symptoms in children with asthma and children with functional gastrointestinal disorders (FGIDs). METHODS: In 108 outpatients aged 3-14 years (45 asthmatic, 63 with FGIDs), we measured the urinary lactulose/mannitol (L/M) ratio, performed allergy skin prick tests and administered questionnaires for recurrent respiratory and gastrointestinal symptoms starting from at least 2 months which persisted over the previous 4 weeks. L/M ratios were compared with previously reported normal values yielded by our chromatographic method (liquid chromatography-mass spectrometry). RESULTS: High L/M ratios (>0.030) were less frequent in asthmatic children than in children with FGIDs (9/45: 20% vs. 41/63: 65%, P < 0.001). High L/M ratios were associated with gastrointestinal symptoms in 8/9 asthmatic (P < 0.05) and 39/41 subjects with FGIDs (P < 0.005). L/M ratios were not associated with respiratory symptoms or atopy. In a regression model, a high L/M was predicted by low height, absence of asthma and presence of gastrointestinal symptoms (r = 0.72, P < 0.001). CONCLUSIONS: Increased intestinal permeability is associated with recurrent gastrointestinal symptoms rather than with recurrent respiratory symptoms in both asthmatic children and those with FGIDs. Our findings do not support the hypothesis of mucosal intestinal damage following an inflammatory stimulus in the respiratory mucosa.

Antibiotic resistance in wastewater: occurrence and fate of Enterobacteriaceae producers of class A and class C ß-lactamases.

Antibiotics have been intensively used over the last decades in human and animal therapy and livestock, resulting in serious environmental and public health problems, namely due to the antibiotic residues concentration in wastewaters and to the development of antibiotic-resistant bacteria. This study aimed to access the contribution of some anthropological activities, namely urban household, hospital and a wastewater treatment plant, to the spread of antibiotic resistances in the treated wastewater released into the Mondego River, Coimbra, Portugal. Six sampling sites were selected in the wastewater network and in the river. The ampicillin-resistant Enterobacteriaceae of the water samples were enumerated, isolated and phenotypically characterized in relation to their resistance profile to 13 antibiotics. Some isolates were identified into species level and investigated for the presence of class A and class C -lactamases. Results revealed high frequency of resistance to the -lactam group, cefoxitin (53.5%), amoxicillin/clavulanic acid combination (43.5%), cefotaxime (22.7%), aztreonam (21.3) cefpirome (19.2%), ceftazidime (16.2%) and to the non--lactam group, trimethoprim/sulfamethoxazol (21.1%), tetracycline (18.2%), followed by ciprofloxacin (14.1%). The hospital effluent showed the higher rates of resistance to all antibiotic, except two (chloramphenicol and gentamicin). Similarly, higher resistance rates were detected in the wastewater treatment plant (WWTP) effluent compared with the untreated affluent. Regarding the multidrug resistance, the highest incidence was recorded in the hospital sewage and the lowest in the urban waste. The majority of the isolates altogether are potentially extended-spectrum -lactamases positive (ESBL(+)) (51.9%), followed by AmpC(+) (44.4%) and ESBL(+)/AmpC(+) (35.2%). The most prevalent genes among the potential ESBL producers were blaOXA (33.3%), blaTEM (24.1%) and blaCTX-M (5.6%) and among the AmpC producers were blaEBC (38.9%), blaFOX (1.9%) and blaCIT (1.9%). In conclusion, the hospital and the WWTP activities revealed to have the highest contribution to the spread of multidrug resistant bacteria in the study area. Such data is important for future management of the environmental and public health risk of these contaminants. This is the first embracing study in the water network of Coimbra region on the dissemination of antibiotic resistance determinants. Moreover, it is also the first report with the simultaneous detection of multiresistant bacteria producers of AmpC and ESBLs -lactamases in aquatic systems in Portugal.

Gastroesophageal reflux disease vs. Panayiotopoulos syndrome: an underestimated misdiagnosis in pediatric age?

Autonomic signs and symptoms could be of epileptic or nonepileptic origin, and the differential diagnosis depends on a number of factors which include the nature of the autonomic manifestations themselves, the occurrence of other nonictal autonomic signs/symptoms, and the age of the patient. Here, we describe twelve children (aged from ten months to six years at the onset of the symptoms) with Panayiotopoulos syndrome misdiagnosed as gastroesophageal reflux disease. Gastroesophageal reflux disease and Panayiotopoulos syndrome may represent an underestimated diagnostic challenge. When the signs/symptoms occur mainly during sleep, a sleep EEG or, if available, a polysomnographic evaluation may be the most useful investigation to make a differential diagnosis between autonomic epileptic and nonepileptic disorders. An early detection can reduce both the high morbidity related to mismanagement and the high costs to the national health service related to the incorrect diagnostic and therapeutic approaches. To decide if antiseizure therapy is required, one should take into account both the frequency and severity of epileptic seizures and the tendency to have potentially lethal autonomic cardiorespiratory involvement. In conclusion, we would emphasize the need to make a differential diagnosis between gastroesophageal reflux disease and Panayiotopoulos syndrome in patients with "an unusual" late-onset picture of GERD and acid therapy-resistant gastroesophageal reflux, especially if associated with other autonomic symptoms and signs.

Adenotonsillectomy and orthodontic therapy in pediatric obstructive sleep apnea.

PURPOSE: Rapid maxillary expansion (RME) is an additional treatment in pediatric obstructive sleep apnea (OSA). The aim of this study was to present data about the outcome of adenotonsillectomy (AT) and of RME in a clinical sample of pediatric OSA. METHODS: We consecutively enrolled children with OSA to undergo RME or AT. The age and the severity of OSA are the main factors involved in the choice of treatment. A polysomnography was performed at the baseline (i.e., before treatment, T0) and 1 year after treatment (T1). RESULTS: A total of 52 subjects fulfilled the inclusion criteria. Twenty-five children underwent AT (group 1) and 22 children underwent RME (group 2). Five children underwent both treatments (group 3). Children in group 2 were older, had a longer disease duration, a higher body mass index (BMI), a lower apnea-hypopnea index (AHI), and a lower arousal index at T0 than children in group 1. After 1 year, BMI percentile and overnight mean saturation increased in group 1 while AHI and arousal index decreased. In group 2, mean overnight saturation increased while AHI decreased. Children in group 3 displayed a significant decrease in AHI from T0 to T1. CONCLUSIONS: Our data demonstrate that both treatments help to improve OSA, and a multidisciplinary approach to treatment is suggested.

Urinary concentration of 8-isoprostane as marker of severity of pediatric OSAS.

BACKGROUND: F2-isoprostanes are considered to be a reliable standard biomarker of oxidative stress in vivo because they are not influenced by the intake of lipids in the diet, and they are chemically stable molecules and easily detected. This study aimed to test the hypothesis that 8-isoprostane level is a useful marker to valuate the severity of pediatric obstructive sleep apnea (OSA). METHODS: Sixty-five children with sleep-disordered breathing (SDB) (mean age 5.9±2.0 years; 63.1% males) were recruited. The urine sample for the measurement of 8-isoprostane was collected the morning after the polysomnographic recording. Children were divided into two groups according to their apnea-hypopnea index (AHI). RESULTS: Urinary 8-isoprostane levels positively correlated with the sleep clinical record score (r=0.38, p=0.002) and AHI (r=0.24, p=0.05) and negatively correlated with age (r=-0.36, p=0.003) and body surface area (r=-0.38, p=0.002). Urinary 8-isoprostane levels were significantly higher in the group with AHI of ≥5 events (ev)/h than in the group with AHI of <5 ev/h (p<0.01). CONCLUSIONS: Urinary 8-isoprostane may be used as a specific inflammatory marker to predict the severity of OSA; this method has the advantage of being noninvasive and easy to use in both compliant and noncompliant children.

The cooccurrence of interictal discharges and seizures in pediatric sleep-disordered breathing.

Studies in the literature data have shown that the prevalence of obstructive sleep apnea (OSA) in children with epilepsy is high and that treatment for OSA leads to a reduction in the number of seizures; by contrast, few studies have demonstrated an increased prevalence of interictal epileptiform discharges (IEDs) or epilepsy in children with sleep-disordered breathing (SDB). The aim of the present study was to confirm the high prevalence of IEDs or epilepsy in a large sample of children with SDB and to collect follow-up data. Children were recruited prospectively and underwent their first video-polysomnography (video-PSG) for SDB in a teaching hospital sleep center. Of the 298 children who fulfilled the diagnostic criteria for sleep-disordered breathing, 48 (16.1%) children were found to have IEDs, three of these 48 children were also found to have nocturnal seizures (two females diagnosed with rolandic epilepsy and a male diagnosed with frontal lobe epilepsy). Only 11 subjects underwent a second video-PSG after 6months; at the second video-PSG, the IEDs had disappeared in six subjects, who also displayed a reduced AHI and an increased mean overnight saturation. Thirty-eight of the 250 children without IEDs underwent a second video-PSG after 6months. Of these 250 children, four, who did not display any improvement in the respiratory parameters and were found to experience numerous stereotyped movements during sleep, were diagnosed with nocturnal frontal lobe epilepsy. Our study confirms the high prevalence of IEDs in children with SDB. Follow-up data indicate that they may recede over time, accompanied by an improvement of sleep respiratory parameters.

Within-breath oscillometry for identifying exercise-induced bronchoconstriction in pediatric patients reporting symptoms with exercise.

Background: Evaluating oscillometry parameters separately for the inspiratory and expiratory breath phases and their within-breath differences can help to identify exercise-induced bronchoconstriction (EIB) in pediatric outpatients disclosing exercise-induced symptoms (EIS). Aims: To assess the response in impedance parameters following an exercise challenge in patients reporting EIS. Methods: Sixty-eight patients reporting EIS (34 asthmatics and 34 suspected of asthma, age mean = 10.8 years, range = 6.0-16.0) underwent an incremental treadmill exercise test. Spirometry was performed at baseline and 1, 5-, 10-, 15-, and 20-min post exercise. Oscillometry was performed at baseline and at 3- and 18-min post exercise. Bronchodilator response to 200 µg albuterol was then assessed. EIB was defined as a forced expiratory volume in 1 s (FEV1) fall ≥10% from baseline. Expiratory and inspiratory resistance (Rrs) and reactance (Xrs), their z-score (Ducharme et al. 2022), and their mean within-breath differences (ΔRrs = Rrsexp-Rrsinsp, ΔXrs = Xrsexp-Xrsinsp) were calculated. Receiver operating characteristic (ROC) curves and their areas (AUCs) were used to evaluate impedance parameters' performances in classifying EIB. Results: Asthmatic patients developed EIB more frequently than those suspected of asthma [18/34 (52.9%) vs. 2/34 (5.9%), p < 0.001]. In the 20 subjects with EIB, Rrsinsp, Rrsexp, Xrsinsp, and Xrsexp peaked early (3'), and remained steady except for Xrsinsp, which recovered faster afterward. ΔXrs widened 18 min following the exercise and reversed sharply after bronchodilation (BD) (-1.81 ± 1.60 vs. -0.52 ± 0.80 cmH2O × s/L, p < 0.001). Cutoffs for EIB leading to the highest AUCs were a rise of 0.41 in z-score Rrsinsp (Se: 90.0%, Sp: 66.7%), and a fall of -0.64 in z-score Xrsinsp (Se: 90.0%, Sp: 75.0%). Accepting as having "positive" postexercise oscillometry changes those subjects who had both z-scores beyond respective cutoffs, sensitivity for EIB was 90.0% (18/20) and specificity, 83.3% (40/48). Conclusion: Oscillometry parameters and their within-breath differences changed markedly in pediatric patients presenting EIB and were restored after the bronchodilator. Strong agreement between z-scores of inspiratory oscillometry parameters and spirometry supports their clinical utility, though larger studies are required to validate these findings in a broader population.

Oscillometry in total laryngectomized patients: A case study.

Attempts to analyze respiratory function of the laryngectomized patient with tests such as spirometry and plethysmography have been described in the literature, highlighting however substantial difficulties. Oscillometry, through the forced oscillation technique (FOT), measures the mechanical properties of the respiratory system minimizing the problems related to the patient's lack of compliance. This methodology has never been applied to these patients and therefore represents a new perspective in the analysis of respiratory function.

Does a parent-reported history of pneumonia increase the likelihood of respiratory symptoms needing therapy in asthmatic children and adolescents?

BACKGROUND: Asthmatic children and adolescents attending outpatient clinics often have a history of pneumonia. Whether respiratory symptoms, lung function, and airway inflammation differ in asthmatic patients with and without a history of pneumonia remains controversial. AIMS: To compare clinical, lung functional, and inflammatory variables in asthmatic outpatients with and without a history of pneumonia. Methods. In 190 asthmatic outpatients, aged 6-18 years, we assessed respiratory symptoms, lung function (flows, volumes, and pulmonary diffusion capacity, DLCO/VA), and atopic-airway inflammation as measured by the fractional concentration of exhaled nitric oxide (FE(NO)). A previous medical and radiological diagnosis of pneumonia was defined as "recurrent pneumonia" if subjects had at least three pneumonia episodes or two episodes within a year. RESULTS: Of the 190 outpatients studied, 38 (20%) had a history of pneumonia. These patients had more frequent upper-respiratory symptoms, nighttime awakenings in the past 4 weeks, daily use of inhaled corticosteroids, and lower FE(NO) than the 152 asthmatic children without previous pneumonia (FE(NO): 20.6 ppb, 95% CI: 15.2-28.0 vs. 31.1 ppb, 95% CI: 27.0-35.8; p < .05). Of the 38 patients with previous pneumonia, 14 had recurrent pneumonia. Despite comparable lung volumes and flows, they also had lower DLCO/VA than asthmatic children with no recurrent pneumonia and asthmatic children without previous pneumonia (DLCO/VA%: 91.2 ± 11.3 vs. 108.5 ± 14.7 vs. 97.9 ± 18.6, p < .05). CONCLUSION: Respiratory assessment in asthmatic children and adolescents with a history of pneumonia, especially recurrent pneumonia, often discloses symptoms needing corticosteroid therapy, and despite normal lung volumes and flows, mild reductions in the variables reflecting gas diffusion and atopic-airway inflammation (DLCO/VA and FE(NO)). Whether these respiratory abnormalities persist in adulthood remains an open question.

Short lingual frenulum as a risk factor for sleep-disordered breathing in school-age children.

BACKGROUND: Recent evidence has emphasized the role of a short lingual frenulum in the pathogenesis of sleep-disordered breathing (SDB) in childhood. The oral dysfunction induced by a short frenulum may promote oral-facial dysmorphism, decreasing the size of upper airway lumen and increasing the risk of upper airway collapsibility during sleep. The aim of this study was to evaluate the presence of a short lingual frenulum as risk factor for SDB in children of school age, with and without snoring, who were recruited from the community. METHODS: Children aged 6-14 years were recruited from a school in Rome. For all participants, the previously described Sleep Clinical Record (SCR) was completed, and orthodontic evaluation and measurement of lingual frenulum were performed. Tongue strength and endurance were evaluated in all participants using the Iowa Oral Performance Instrument (IOPI). SDB was defined as positive SCR (≥6.5). RESULTS: We assessed 504 children with mean age of 9.6 ± 2.3 years, and in 114 of them (22.6%) a short frenulum was identified. Children with a short lingual frenulum were at significantly higher risk for a positive SCR compared to those with a frenulum of normal length (odds ratio = 2.980, 95% confidence interval = 1.260-6.997). Participants with positive or negative SCR did not differ in tongue strength or endurance. CONCLUSION: Short lingual frenulum is a risk factor for SDB. An early multidisciplinary approach and screening for SDB are indicated when this anatomical abnormality is recognized.

Urinary and exhaled biomarkers of exercise-induced bronchoconstriction in atopic asthmatic children.

BACKGROUND: Exercise-induced bronchoconstriction (EIB) reflects poor asthma control. Assessing noninvasive biomarkers associated with EIB could help to monitor patients in the pediatric age. AIMS: To test exhaled and urinary biomarkers for assessing EIB in atopic asthmatic children. METHODS: In 45 atopic patients (11.1 ± 1.8 years, 25 males) we measured the fractional exhaled nitric oxide (FENO ), its alveolar (CaNO), and bronchial (J'awNO) components corrected for the trumpet shape of the airways and axial NO diffusion (TMAD), concentrations of urinary adenosine and 8-hydroxy-2'-deoxyguanosine (8-OxodG), blood eosinophils count, total immunoglobulin E , skin prick tests, and baseline spirometry before a treadmill exercise challenge. Forty healthy control subjects participated solely to baseline measurements. RESULTS: Patients yielded higher FENO and urinary adenosine concentrations than healthy controls. After the challenge, 18 patients (40%) had EIB; these patients had higher levels of CaNO, CaNO TMAD, and urinary adenosine than patients without EIB. Baseline spirometry, FE NO , JawNO, JawNO TMAD, urinary 8-OxodG, allergy, and blood eosinophil counts were found similar in both groups. In multiple linear regression, the fall in FEV 1 was explained by CaNO TMAD, urinary adenosine and blood eosinophil count, whereas the fall in FEF 25-75 was explained by CaNO TMAD and blood eosinophil count. Both CaNO TMAD ≥10.5 ppb and urinary adenosine ≥406 nmol/mmol Cr predicted a fall in FEV 1 ≥10%, while only CaNO TMAD ≥10.5 ppb predicted a fall in FEF 25-75 ≥26%. CONCLUSION: Concentrations of peripheral airway NO are complementary with urinary adenosine for assessing EIB and promising tools of asthma control in pediatric patients with the atopic phenotype.

Variations in exhaled nitric oxide in children with asthma during a 1-week stay in a mountain village sanatorium.

Knowing about spontaneous variations in the fractional concentration of exhaled nitric oxide (FE(NO)) could improve monitoring of airway inflammation in asthmatic children. We aimed to assess FE(NO) variations (expiratory flow 50 mL/sec) in subjects maintained in similar environmental conditions. We tested spirometry and FE(NO) in symptom-free asthmatic children (9 corticosteroid-naive, 8 corticosteroid-treated) during a 1-week stay in a countryside sanatorium and in their healthy relatives (n = 12) staying in the immediate neighborhood on summer holiday (total 29 children, M/F:14/15, 5.8-16.8 yrs). Testing sessions were repeated every 12 hours (8:00 am, 8:00 pm) for 2 days and again on day 7. Measurements were defined as reproducible when they agreed with an intraclass correlation coefficient (ICC) above 0.60; deviation from mean differences was assessed by the coefficient of repeatability (CR = 2 SD). Lung function remained constant throughout the week in all groups. Baseline FE(NO) levels in corticosteroid-naive asthmatic children tended to decrease at the end of the week (from 13.9 ppb, 95% CI 12.2-19.1 to 9.2 ppb, 95% CI 5.8-15.9, p = 0.057). No differences were found between nocturnal and diurnal FE(NO). Within-session reproducibility for two FE(NO) measurements was high (ICC 0.99 in all groups and CR, 0.9 to 1.3 ppb). Between-session FE(NO) reproducibility at 12 hours and 24 hours was still high for each group but decreased markedly after 6 days in corticosteroid-naive asthmatic children (ICC 0.79 and CR 9.6 ppb at 24 hours vs. ICC 0.13 and CR 20.8 ppb after 6 days), whereas it decreased slightly in corticosteroid-treated asthmatics (from ICC 0.89 and CR 3.1 ppb to ICC 0.88 and CR 3.0 ppb) and healthy children (from ICC 0.79 and CR 4.8 ppb to ICC 0.65 and CR 5.7 ppb). In conclusion, in healthy subjects and in asthmatic children receiving therapy with inhaled corticosteroids (but not in corticosteroid-naive subjects), FE(NO) measurements are reproducible across a week.

Comparison of two exhaled biomarkers in children with and without sleep disordered breathing.

OBJECTIVE: Airway oxidative stress and inflammation are likely to be involved in sleep disordered breathing (SDB) in children. We aimed to measure concentrations of 8-isoprostane (8-IsoP) in the exhaled breath condensate (EBC) and exhaled nitric oxide (FENO) in patients with SBD and healthy children, in order to assess the relationship between these two biomarkers, disease severity, and overnight changes. METHODS: Patients with SDB (n = 46) and healthy controls (n = 20) aged 4.5-15.1 years (M/F: 36/30) underwent exhaled measurements. Patients with SDB underwent standard polysomnography to define primary snoring (PS: AHI < 1) and obstructive sleep apnea (OSA). Upon awakening the following morning, FENO was measured and EBC was collected for the measurement of EBC 8-IsoP. RESULTS: OSA patients yielded higher awakening levels of 8-IsoP in EBC than PS patients and control subjects. The 8-IsoP levels, though not FENO, correlated with AHI (r = 0.40, p = 0.003) and SaO2 (r = -0.50, p = 0.001). Cut-off levels of 8-IsoP predicted OSA with a high AUC value (0.84, p = 0.000). Sensitivity and specificity for 8-IsoP levels above the percentile 50 (33.3 pg/mL) were 76.5% and 78.1%, respectively. 8-IsoP levels did not change from the evening to morning session, whereas morning FENO levels rose significantly only in patients with mild OSA (p = 0.03). CONCLUSION: Levels of 8-IsoP, though not FENO, distinguish children with OSA from those with PS or healthy, correlate with disease severity and closely predict OSA in the whole sample.

Reduced exhaled nitric oxide in children after testing of maximal expiratory pressures.

Spirometry in adult subjects can induce a fall in concentration of exhaled nitric oxide (FE(NO)). Scarce information is available on the FE(NO) decrease after spirometry or after other forced lung-function maneuvers in children. We compared changes in FE(NO) induced by repeated spirometry and testing of maximal expiratory pressures (P(Emax)). Twenty-four sex- and age-matched children aged 9-18 years (mean age +/- SD, 13.3 +/- 2.8 years; 12 healthy, 12 asthmatic) were allocated to 1-week-apart sessions of repeated maneuvers of either forced vital capacity (FVC) or P(Emax). Baseline FE(NO) measurements were followed by FVC or P(Emax) maneuvers every 15 min for 45 min, whereas FE(NO) was measured at each step for 60 min. After repeated P(Emax) but not after FVC maneuvers, FE(NO) values decreased significantly from baseline in both groups. In healthy children, geometric mean FE(NO) (95% confidence intervals) decreased from 9.1 (7.0-11.8) ppb at baseline to 8.2 (6.3-10.6) ppb at 15 min and 7.7 (5.6-10.6) ppb at 30 min (P < 0.05 and P < 0.01, respectively), and remained unchanged at 45 and 60 min. In asthmatic children, FE(NO) levels fell from 21.6 (13.3-34.9) ppb at baseline to 15.1 (9.1-25.1) ppb at 15 min and remained low at 30, 45, and 60 min: 17.8 (10.7-29.5) ppb, 17.5 (10.2-30.1) ppb, and 17.6 (10.6-29.2) ppb, P < 0.01, for all differences from baseline. Repeated P(Emax) and FVC maneuvers increased FE(NO) variability, as compared with repeated FE(NO) measurements alone. Previous forced lung-function maneuvers may affect FE(NO) measurements in children. Although P(Emax) testing has a greater influence than spirometry on FE(NO) levels in children, both procedures should be avoided before measuring FE(NO).

Lead neurotoxicity in children: is prenatal exposure more important than postnatal exposure?

Numerous studies indicate that low-level lead poisoning causes mild mental retardation and low IQ scores in children. The general mean lead intake in the adult European population corresponds to a reassuring 14% (0.5-56%) of the tolerable daily intake: at this low level of exposure only few children (less than 10%) have blood lead levels (PbB) higher than 10 microg/dl, previously considered the PbB of concern. In more recent years data now suggest that even when 'the lifetime average blood lead concentration' is below 10 microg/dl an inverse association exists with intelligence quotient (IQ) scores. Two-thirds (45-75%) of lead in blood, however, comes from long-term tissue stores and this is especially true for newborn infants and pregnant women. Several data suggest that for lead the main toxic event is prenatal exposure: therefore we should focus our attention on maternal lead stores and whenever possible avoid their mobilization during pregnancy. In this regard we should design appropriate studies to confirm whether dietary supplementations can reduce bone resorption and lead mobilization during pregnancy. The hypothesis that the amount of maternal bone lead stores is the relevant parameter for predicting the level of neurotoxicity of this metal gives some optimism for the future: if we study children whose mothers never underwent high environmental pollution (born after the withdrawal of lead from gasoline) and hence have relatively low bone lead stores we could find that, at the population level, lead has little influence on children IQ scores.

Autonomic imbalance during apneic episodes in pediatric obstructive sleep apnea.

OBJECTIVES: To investigate the activity of the autonomic nervous system (ANS) during sleep in children with obstructive sleep apnea (OSA), in order to detect a possible cardiac ANS imbalance analyzing heart rate variability (HRV). METHODS: 43 subjects between 4 and 12 years of age (7.26 ± 2.8 years), undergoing a diagnostic assessment for OSA were evaluated. A time domain index (R-apnea index) was developed to evaluate HRV strictly related to obstructive events during sleep. Poincaré plot of RR intervals during the whole night was calculated. RESULTS: R-apnea index was negatively correlated with apnea hypopnea index (AHI) (r=-0.360, p=0.028). AHI and the duration of the disease were the only variables that were significantly correlated with R-apnea index. Three groups were subsequently created according to polysomnographic findings considering AHI. R-apnea index resulted significantly lower in patient with severe OSA compared to primary snoring/mild OSA subjects (p<0.05). Looking at Poincaré plot, SD1 showed a diminishing trend with severity of OSA, however not reaching statistical significance. CONCLUSIONS: Our findings suggest an autonomic impairment in OSA children evidenced by the altered HRV both in the very short term (R-apnea index) and in short term (SD1). SIGNIFICANCE: R-apnea index is an easy and cheap method to undelay early ANS imbalance.

Oximetry in obese children with sleep-disordered breathing.

BACKGROUND: Obesity is an important risk factor for obstructive sleep apnea syndrome (OSAS), and obese children with OSAS have frequently shown oxygen desaturations when compared with normal-weight children. The aim of our study was to investigate the oximetry characteristics in children with obesity and sleep-disordered breathing (SDB). METHODS: Children referred for suspected OSAS were enrolled in the study. All children underwent sleep clinical record (SCR), pulse oximetry, and polysomnography (PSG). RESULTS: A total of 248 children with SDB were recruited (128 obese and 120 normal-weight children). Obese children showed higher oxygen desaturation index (ODI) and lower nadir oxygen saturation (nadir SaO2) compared to non-obese children (p < 0.05). ODI and nadir SaO2 correlated with obesity (p < 0.05). The SCR evaluation showed that deep bite and overjet were more common among obese children (p < 0.05), whereas habitual nasal obstruction and arched palate were more common among non-obese children (p < 0.05). Furthermore, skeletal malocclusion and tonsillar hypertrophy were significant risk factors in obese children associated with severe desaturation (p < 0.05). CONCLUSION: Obese children with SDB have a more significant oxygen desaturation; adeno-tonsillar hypertrophy is not the only important risk factor for its development but also the presence of malocclusions.