Marilisa Montesano

Additive effect of eosinophilia and atopy on exhaled nitric oxide levels in children with or without a history of respiratory symptoms.

Although atopy and blood eosinophilia both influence exhaled nitric oxide (eNO) measurements, no study has quantified their single or combined effect. We assessed the combined effect of atopy and blood eosinophilia on eNO in unselected schoolchildren. In 356 schoolchildren (boys/girls: 168/188) aged 9.0–11.5 yr, we determined eNO, total serum IgE, blood eosinophil counts and did skin prick tests (SPT) and spirometry. Parents completed a questionnaire on their childrens current or past respiratory symptoms. Atopy was defined by a SPT > 3 mm and eosinophilia by a blood cell count above the 80th percentile (>310 cells/ml). eNO levels were about twofold higher in atopic–eosinophilic subjects than in atopic subjects with low blood eosinophils [24.3 p.p.b. (parts per billion) vs. 14.1 p.p.b.] and than non‐atopic subjects with high or low blood eosinophils (24.3 p.p.b. vs. 12.2 p.p.b. and 10.9 p.p.b.) (p < 0.001 for both comparisons). The additive effect of atopy and high eosinophil count on eNO levels remained unchanged when subjects were analyzed separately by sex or by a positive history of wheeze (n = 60), respiratory symptoms other than wheeze (n = 107) or without respiratory symptoms (n = 189). The frequency of sensitization to Dermatophagoides (Dpt or Dpf) was similar in atopic children with and without eosinophilia (66.2% and 67.4%, respectively); eosinophilia significantly increased eNO levels in Dp‐sensitized children as well in children sensitized to other allergens. In a multiple linear regression analysis, eNO levels were mainly explained by the sum of positive SPT wheals and a high blood eosinophil count (t = 4.8 and 4.3, p = 0.000), but also by the presence of respiratory symptoms (especially wheeze) and male sex (t = 2.6 and 2.0, p = 0.009 and 0.045, respectively). Measuring eNO could be a simple, non‐invasive method for identifying subjects at risk of asthma in unselected school populations.

Sleep apnoea in children with diabetes mellitus: effect of glycaemic control

Aims/hypothesis. Patients with diabetes mellitus commonly have cardiovascular autonomic dysfunction and an abnormal ventilatory pattern during sleep. Few data are available on these changes in childhood diabetes. We investigated whether young diabetic children with or without diabetic neuropathy have ventilatory dysfunction during sleep and if so, whether these autonomic changes are related to the duration of diabetes and glycaemic control.¶Methods. We studied 25 children with insulin-dependent diabetes mellitus (19 boys, mean age 7.72 ± 1.99 years). All patients were insulin-dependent at diagnosis; blood samples for HbA1 c assay were collected on the morning before testing and at 3-month intervals during the preceding year. Patients and control subjects (20 age-matched healthy children, 15 boys) underwent overnight polysomnography.¶Results. More diabetic patients than control subjects had sleep apnoeas (p = 0.006); apnoeas in patients also lasted longer (p = 0.07). Patients with poorly controlled diabetes had more apnoeas than patients with well–controlled diabetes and than healthy control subjects (p < 0.0001). Respiratory events during sleep correlated significantly with glycaemic control (r = 0.360; p = 0.09) and with the duration of diabetes (r = 0.430; p = 0.04).¶Conclusion/interpretation. We conclude that respiratory control is compromised very early in children with diabetes. These anomalies are closely related to the duration of diabetes and to glycaemic control. In young children with diabetes, screening of ventilatory control using recording techniques that are simpler than polysomnography could provide an early indication that an adverse cardiopulmonary reaction has begun. [Diabetologia (2000) 43: 696–702]

Sleep clinical record: an aid to rapid and accurate diagnosis of paediatric sleep disordered breathing

Overnight polysomnography (PSG) is an expensive procedure which can only be used in a minority of cases, although it remains the gold standard for the diagnosis of sleep disordered breathing (SDB). The objective of this study was to develop a simple, PSG-validated tool to screen SDB, thus reducing the use of PSG. For every participant we performed PSG and a sleep clinical record was completed. The sleep clinical record consists of three items: physical examination, subjective symptoms and clinical history. The clinical history analyses behavioural and cognitive problems. All three items were used to create a sleep clinical score (SCS). We studied 279 children, mean±sd age 6.1±3.1 years, 63.8% male; 27.2% with primary snoring and 72.8% with obstructive sleep apnoea (OSA) syndrome. The SCS was higher in the OSA syndrome group compared to the primary snoring group (8.1±9.6 versus 0.4±0.3, p<0.005), correlated with apnoea/hypopnoea index (p=0.001) and had a sensitivity of 96.05%. Positive and negative likelihood ratios were 2.91 and 0.06, respectively. SCS may effectively be used to screen patients as candidates for PSG study for suspected OSA syndrome, and to enable those with a mild form of SDB to receive early treatment.

Diffusing capacity for carbon monoxide in children with type 1 diabetes

Aims/hypothesisFew data are available on lung dysfunction in children with diabetes. We studied the association of pulmonary function variables (flows, volumes and alveolar capillary diffusion) with disease-related variables in children with type 1 diabetes mellitus.MethodsWe studied 39 children with type 1 diabetes (mean age 10.9±2.6 years, disease duration 3.6±2.4 years, insulin·kg−1·day−1 0.77±0.31) and 30 healthy control children (mean age 10.4±3.0 years). Pulmonary function tests included spirometry, N2 wash-out and the single-breath diffusing capacity for carbon monoxide (DLCO) corrected for the alveolar volume (DLCO/VA). Glycaemic control was assessed on the basis of HbA1c, with HbA1c values of 8% or less considered to indicate good glycaemic control, and HbA1c values of 8% or more considered to indicate poor control.ResultsChildren with poor glycaemic control had comparable percentage values for predicted flows and volumes but lower DLCO/VA values than children with good glycaemic control and healthy control children (86.7±12.6 vs 99.8±18.4 and 102.0±15.7; p<0.05). The predicted DLCO/VA percentages correlated with HbA1c levels (r=−0.39, p=0.013). A multiple regression analysis (stepwise model) controlling for HbA1c levels and other disease-related variables (age of disease onset, disease duration, daily insulin dose/kg, sex) identified HbA1c levels as the sole predictor of DLCO/VA in percent.Conclusions/interpretationIn children with type 1 diabetes, the diffusing capacity diminishes early in childhood and is associated with poor metabolic control. Although low DLCO/VA levels in these children probably reflect pulmonary microangiopathy induced by type 1 diabetes, other factors presumably influencing CO diffusion capacity measurements (e.g. a left shift in HbA1c resulting in high O2 binding and low CO binding) could explain the apparent capillary and alveolar basal membrane dysfunction.

Sleep cyclic alternating pattern analysis in infants with apparent life-threatening events: A daytime polysomnographic study

OBJECTIVE Non-REM sleep is characterized by a physiologic oscillating pattern that exhibits different levels of arousal, coded as cyclic alternating pattern. The aim of this study was to analyze the development of cyclic alternating pattern parameters in a group of infants with apparent life-threatening events. METHODS A total of 26 infants with apparent life-threatening events (14 females, mean age 3.4 months, 2.37 S.D., age range 0.5-9 months) were studied while they slept in the morning between feedings, by means of a 3-h video-electroencephalographic-polygraphic recording. Sleep was visually scored using standard criteria. The control group was composed of 36 healthy infants (16 females, mean age 3.2 months, 2.17 S.D., age range 0.5-9 months). RESULTS Children with apparent life-threatening events showed an increased frequency of periodic breathing, gastroesofageal reflux and of other risk conditions. They presented also an increased obstructive apnoea/hypopnea index. A full NREM sleep development was found in a significantly smaller percentage of patients, and they showed a significant reduction of the percentage of REM sleep, of cyclic alternating pattern A1 subtypes, an increased percentage of A2 and A3 subtypes and increased index of A2, A3 subtypes and arousal, compared to normal controls. Cyclic alternating pattern rate showed a significant positive correlation with age, only in controls. CONCLUSIONS Our results show a higher level of arousal and an increased non-REM sleep discontinuity in babies with apparent life-threatening events, compared to controls. SIGNIFICANCE The enhanced mechanism of arousal might counteract life-threatening events and represent an important neurophysiologic distinction from future victims of sudden infant death syndrome who also experience similar events.

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 (FENO) could improve monitoring of airway inflammation in asthmatic children. We aimed to assess FENO variations (expiratory flow 50 mL/sec) in subjects maintained in similar environmental conditions. We tested spirometry and FENO 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 FENO 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 FENO. Within-session reproducibility for two FENO measurements was high (ICC 0.99 in all groups and CR, 0.9 to 1.3 ppb). Between-session FENO 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-naïve subjects), FENO measurements are reproducible across a week.

Sleep clinical record: what differences in school and preschool children?

The sleep clinical record (SCR) may be a valid method for detecting children with obstructive sleep apnoea (OSA). This study aimed to evaluate whether there were differences in SCR depending on age and to identify the possible risk factors for OSA development. We enrolled children with sleep disordered breathing between 2013 and 2015, and divided them according to age into preschool- and school-age groups. All patients underwent SCR and polysomnography. OSA was detected in 81.1% and 83.6% of preschool- and school-age groups, respectively. Obesity, malocclusions, nasal septal deviation and inferior turbinate hypertrophy were significantly more prevalent in school-age children (p<0.05); however, only tonsillar hypertrophy had significant hazard ratio (2.3) for OSA development. Saddle nose, nasal hypotonia, oral breathing and tonsillar hypertrophy were significantly more prevalent for development of OSA in preschoolers (p<0.03). The SCR score was significantly higher among preschool children than in school-age children (8.4±2.22 versus 7.9±2.6; p=0.044). Further, SCR score >6.5 had a sensitivity of 74% in predicting OSA in preschool children with positive predictive value of 86% (p=0.0001). Our study confirms the validity of the SCR as a screening tool for patient candidates for a PSG study for suspected OSA, in both school and preschool children. The differences in sleep clinical record between school and preschool children suspected to have OSA http://ow.ly/X778Q