Feasibility of structured light plethysmography for the evaluation of lung function in preschool children with asthma.

BACKGROUND: Structured light plethysmography (SLP) is a new noninvasive technology to capture the movement of the thoracic and abdominal wall, and to assess some parameters indicative for lung function. OBJECTIVE: The purpose of the study was to evaluate the feasibility of SLP in children with asthma. METHODS: A total of 52 patients were enrolled: 25 with asthma exacerbation (group 1), 13 with well-controlled asthma (group 2), and 14 healthy controls (group 3). Every patient underwent SLP evaluation and a lung function test. RESULTS: SLP evaluations showed that the ratio of inspiratory flow at 50% of tidal volume (Vt) to expiratory flow at 50% of Vt, in which Vt is taken to be the exhaled chest wall movement, and flow is taken to be the time derivative of the chest wall movement (IE50) value increased in group 1 compared with groups 2 and 3, with statistical significance (p = 0.018); the data were consistent with the spirometry parameter. A correlation between the IE50 and forced expiratory volume in the first second of expiration was highlighted (r = -0.35, p = 0.019). CONCLUSION: SLP assessed airway obstruction, and its use in clinical practice could be applied in preschool children in future studies.

Antioxidant supplementation and exhaled nitric oxide in children with asthma.

BACKGROUND: The effect of allergen avoidance on airway inflammation is similar to that observed with treatment with inhaled steroids, whereas inhaled steroids have no effect on oxidative stress-induced inflammation. OBJECTIVE: The aim of this study was to retrospectively evaluate the potential effect of an antioxidant dietary supplement on exhaled nitric oxide over a month in pediatric patients on stable antiasthma treatment. METHODS: Forty-seven children with moderate-to-severe asthma were retrospectively evaluated. All the patients were sensitive to Dermatophagoides pteronyssinus and Dermatophagoides farinae, and they were receiving the minimum inhaled corticosteroid dosage required to maintain adequate control. Within a few weeks of admission at Misurina Hospital in the Alps, the regular treatment was gradually reduced, then some children who were receiving a daily dose of inhaled corticosteroids, ≤200 mcg of fluticasone propionate, were prescribed a nutraceutical dietary supplement for at least 4 weeks. Lung function and fractional exhaled nitric oxide (FeNO) measurements were recorded at the beginning and after 1 month of the dietary supplementation. RESULTS: Baseline lung function and FeNO values did not differ between the two groups of patients. After 4 weeks of nutraceutical supplementation, FeNO values decreased, from 19.00 ppb (interquartile range, 14-31 ppb) to 11.00 ppb (interquartile range, 6-23 ppb) (p = 0.03). No significant reduction was observed in the group that did not receive the supplementation, and no significant difference between groups was observed, both at baseline and after 4 weeks of nutraceutical supplementation. CONCLUSION: Supplementation with a nutraceutical of antioxidants and anti-inflammatory compounds, such as curcumin, resveratrol, soy phospholipids, zinc, selenium, and vitamin D, may be associated with reduced airway inflammation, as documented by a fall in FeNO.

Correlation of skin barrier impairment in atopic dermatitis with aeroallergen sensitization.

BACKGROUND: Atopic dermatitis (AD) often predates the development of allergic sensitization in the so-called atopic march. Several studies have pointed out epidermal barrier impairment as a major cause of this evolution. OBJECTIVE: The present study aimed to assess atopic skin integrity by means of transepidermal water loss (TEWL) and Corneometer, and to investigate possible correlations between barrier integrity measurements and the degree of sensitization to aeroallergens (allergy score). METHODS: Sixty-one children (6 months to 17 years old) with AD were clinically evaluated by the Scoring Atopic Dermatitis index. TEWL and Corneometer evaluations were performed on lesion sites as well as on healthy skin. The subjects underwent skin-prick testing, and the severity of allergic sensitization was assessed for each patient by summing all wheal diameters (the allergy score). The same tests were performed in 20 children without AD. RESULTS: In patients with AD, TEWL and Corneometer results were found to be higher and lower, respectively, on eczematous areas in comparison with healthy skin, and differences were significantly correlated to the Scoring Atopic Dermatitis index (p < 0.0001 and p = 0.007, respectively). The TEWL result was significantly higher in nonlesional skin of the patients with AD compared with that of individuals without AD (p = 0.017). Of the patients with AD, 59% were sensitized to inhalant allergens; allergy scores were positively correlated with both AD duration (r = 0.63; p < 0.0001) and nonlesional skin TEWL values (r = 0.46; p = 0.002). No significant correlation was found between allergy scores and skin parameters in subjects without AD. CONCLUSION: Patients with AD are affected by barrier function impairment, even on noneczematous skin. This defect is associated with greater aeroallergen sensitization and may contribute to allergic respiratory symptom development.

Microorganism-induced exacerbations in atopic dermatitis: a possible preventive role for vitamin D?

Atopic dermatitis (AD) is a common skin disease characterized by a complex pathogenesis not completely understood despite numerous studies to date. The clinical patterns result from interactions between genetic disorders determining abnormalities in the epidermis differentiation complex, modification of the cutaneous barrier, and dysfunction of immune responses. Several studies have shown that an alteration of the skin barrier combined with immune dysfunction is important for the onset, maintenance, and risk of exacerbations of the disease. In recent years, new aspects regarding the pathogenesis of the disease, such as the effects of vitamin D (VD) on immunity at the skin level and the role of certain microorganisms (particularly Staphylococcus and Malassezia species) on eczema exacerbations, have been evaluated. This article provides an overview of the evidences supporting the link between VD (deficiency) and microorganisms (skin colonization/sensitization) in AD pathogenesis, based on comprehensive review of the literature. By considering different aspects of disease, it might be possible to improve our understanding, particularly in those patients refractory to conventional treatments. An electronic research strategy was used to search in Medline Pub-Med Library using as research words AD, exacerbation, VD, Staphylococcus aureus (SA), and Malassezia. The results were downloaded and analyzed for systematic review. Few studies actually consider the relationship between VD deficiency (VDD), AD, and SA and Malassezia, but many suggest a correlation between these factors. VDs play a major role against microorganisms in the development of AD and should be considered when treating patients.

Is vitamin D deficiency correlated with childhood wheezing and asthma?

There is increasing evidence that vitamin D regulates immune responses. There is also epidemiological evidence of a relationship between vitamin D deficiency and development of asthma. In addition, several epidemiological studies suggest that low levels of vitamin D during pregnancy and early life are inversely associated with the risk of developing respiratory infections and wheezing in childhood. Vitamin D also seems to reduce asthma exacerbation and increase the response to glucocorticoids. These findings have led to considering a possible link between the occurrence of allergic respiratory diseases and low levels of vitamin D. However, the precise role of vitamin D in the pathogenesis of asthma still remains unclear, emphasizing the need for well-designed trials on vitamin D supplementation to decipher its role in preventing and/or managing the disease. This review examines the relationship that exists between vitamin D deficiency and childhood wheezing and asthma.

Asthma and viruses: is there a relationship?

Asthma is a multifactorial disease in which many factors play a role in its development and exacerbations. Viral infections are known to be the main cause of asthmatic exacerbations and are often the first manifestation of asthma in preschool age. However, there is much evidence suggesting a role of viral infections even in asthma development. Respiratory Syncytial Virus (RSV). has been first associated with an increased risk to develop asthma, but recently new viruses have been proposed to be involved in asthma pathogenesis. Further studies will be needed to demonstrate a causative role of viral infections in asthma development, in order to implement preventive strategies in high-risk children.

Breast-milk characteristics protecting against allergy.

Breast milk and colostrum are the first feeding sources for a child, providing nutrients, growth factors and immunological components, which are crucial for the newborn's correct development and health. Length of exclusive breastfeeding and time of solid foods introduction is a key factor that may influence allergy development. There is an emerging evidence of a relationship between breastfeeding, milk composition and lower risk of chronic diseases, such as diabetes, obesity, hypertension and allergies. This review examines current evidence regarding humoral and cellular characteristics of breast-milk, and potential role of environment, maternal diet and breastfeeding on the allergy development in children.

Colostrum-derived B and T cells as an extra-lymphoid compartment of effector cell populations in humans.

Colostrum contains cellular components that convey immunological protection to offspring. In the present study the main subsets of lymphocytes present in colostrum and in peripheral blood of healthy screened mothers were compared through the evaluation of >15 different flow cytometry markers. Colostrum and peripheral blood samples were collected within 3 days after full-term delivery. Flow cytometry assays and laboratory tests were performed soon after collection. Among B cells, percentages of CD19(+)CD5(+) cells, pertaining to natural immunity system, were significantly higher in colostrum than in peripheral blood (33 vs. 5%, p = 0.047). CD4(+) T cells, effector cells (CD45RA(+)/CD27(-)) and effector memory cells (CD45RA(-)/CD27(-)) were significantly higher in colostrum (p < 0.001) than in peripheral blood, as well as activated CD4(+) T cells (HLA(-)DR(+)) (36% vs. 6% p = 0.0022) and CD4(+) terminally differentiated effector T cells (CD57(+)) (p < 0.001). With regards to CD8(+) T cells, a comparable significant increase in effector (p < 0.02) and effector memory cells (p < 0.001) was also observed. Moreover, an increased surface expression of HLA-DR and CD57 (p < 0.001) on CD8(+) T cells in colostrum was detected. Colostrum contains a different distribution of lymphocyte subsets with respect to peripheral blood from mothers, confirming the observation that lymphocytes probably migrate in milk in a selective way. Colostrum T and B lymphocytes appear to be enriched with subsets possessing effector functions or belonging to the innate immune system, what could transfer a prompt line of defence to offspring.

Nasal mucosa temperature as a marker of disease in children with allergic rhinitis.

BACKGROUND: Allergic rhinitis (AR) is a symptomatic disorder of the nose induced after allergen exposure by an IgE-mediated inflammation of the nasal mucosa. This study was designed to investigate the role of nasal mucosa temperature in AR. METHODS: We investigated the relationship between eosinophilic infiltration, nasal obstruction, and nasal mucosa temperature in 35 children with rhinitis aged 6-12 years. RESULTS: A significant relationship was shown between nasal temperature values and eosinophil infiltration at nasal cytology (p < 0.01). Nasal temperature was also significantly associated with nasal obstruction, assessed in terms of nasal volume (Vol [2-5 cm]; p < 0.05) and minimum cross-sectional area (p < 0.01). No significant correlation emerged between the degree of nasal obstruction and presence of eosinophils at nasal cytology (p > 0.05). CONCLUSION: These results suggest a relationship between nasal temperature and nasal mucosa inflammation and obstruction.

Analysis of urinary parameters as risk factors for nephrolithiasis in children with celiac disease.

PURPOSE: Intestinal malabsorption can cause urinary stone disease via enteric hyperoxaluria. It has been shown that celiac disease, a common malabsorption disorder, is associated with an increased risk of calcium oxalate kidney stones in adults. Since no published data are available in the pediatric population, we analyzed urinary excretion of electrolytes in children with celiac disease to assess the risk of nephrolithiasis. MATERIALS AND METHODS: The study population consisted of 115 children 1 to 16 years old (mean 5 years) with positive serological tests for celiac disease (anti-endomysium and anti-tissue transglutaminase antibodies) referred to us for jejunal biopsy to confirm the diagnosis. Assessment was requested because patients presented with poor growth, anemia, gastrointestinal disorders or a family history of celiac disease. After obtaining informed consent we performed urine tests to measure urinary variables and blood tests to exclude metabolic disorders and evaluate renal function. RESULTS: All patients had a biopsy confirmed diagnosis of celiac disease. Oxaluria was normal in all children studied. However, levels of urinary calcium were decreased in patients with celiac disease and were inversely associated with disease severity (p = 0.0004). CONCLUSIONS: In contrast to adults, increased urinary excretion of oxalate was not detectable in children presenting with celiac disease. Therefore, the risk of nephrolithiasis appears not to be increased compared to healthy children. The observed hypocalciuria probably further decreases the tendency to form kidney stones.

How changes in nutrition have influenced the development of allergic diseases in childhood.

The increasing prevalence of allergic diseases in childhood in the last decades could be linked to concomitant dietary changes, especially with the modified and lower consumption of fruit, vegetables and minerals. The consumption of these foods by pregnant women and children in the first years of life seems to be associated with a reduced risk of asthma and related symptoms. Foods that can prevent the development of wheezing through their antioxidant effects contain vitamin C and selenium; blood levels of these elements correlate negatively with the risk of wheezing. Intake of vitamin E during pregnancy also appears to be correlated with a reduced risk of wheezing for the unborn child. Similarly, low intake of zinc and carotenoids by pregnant women is associated with an increased risk of wheezing and asthma in childhood. Fiber also has anti-inflammatory properties and protective effects against allergic diseases such as atopic dermatitis and asthma. The consumption of fat influences the development of the airways. Populations in Western countries have increased their consumption of n-6 PUFAs and, in parallel, reduced n-3 PUFAs. This has led to decreased production of PGE2, which is believed to have a protective effect against inflammation of the airways. Conflicting hypotheses also concern vitamin D; both an excess and a deficiency of vitamin D, in fact, have been associated with an increased risk of asthma. Further studies on the role of these substances are necessary before any conclusions can be drawn on a clinical level.

Exhaled breath temperature and exercise-induced bronchoconstriction in asthmatic children.

It has been hypothesized that exhaled breath temperature (EBT) is related to the degree of airway inflammation/remodeling in asthma. The purpose of this study was to evaluate the relationship between the level of airway response to exercise and EBT in a group of controlled or partly controlled asthmatic children. Fifty asthmatic children underwent measurements of EBT before and after a standardized exercise test. EBT was 32.92 ± 1.13 and 33.35 ± 0.95°C before and after exercise, respectively (P < 0.001). The % decrease in FEV(1) was significantly correlated with the increase in EBT (r = 0.44, P = 0.0013), being r = 0.49 (P < 0.005) in the children who were not receiving regular inhaled corticosteroids (ICS) and 0.37 (n.s.) in those who were. This study further supports the hypothesis that EBT can be considered a potential composite tool for monitoring asthma.

Diffusion lung capacity of carbon monoxide: A novel marker of airways remodeling in asthmatic children?

Asthma is universally considered a chronic inflammatory disorder of the airways. Several noninvasive markers, such as exhaled nitric oxide (FeNO) and exhaled breath temperature (PletM), have been proposed to evaluate the degree of airway inflammation and remodeling in asthmatic children. The aim of this study was to evaluate the relationship between diffusion lung capacity of carbon monoxide (DLCO) and these inflammatory markers in asthmatic children. We compared data of FeNO, PletM, and DLCO collected in 35 asthmatic children at admission (T0) and discharge (T1) after a period spent in a dust-mite-free environment (Misurina, Italian Dolomites, 1756 m). PletM showed a reduction from 29.48°C at T0 to 29.13°C at T1 (p = 0.17); DLCO passed from 93 to 102 (p = 0.085). FeNO mean value was 29.7 ppb at admission and 18.9 ppb at discharge (p = 0.014). Eosinophil mean count in induced sputum was 4 at T0 and 2 at T1 (p = 0.004). Spearman standardization coefficient beta was 0.414 between eosinophils and FeNO and -0.278 between eosinophils and DLCO. Pearson's correlation index between DLCO and PletM was -0.456 (p = 0.019). A negative correlation between DLCO and PletM was found. However, DLCO did not show a significant correlation with FeNO and eosinophils in the airways. Additional studies are needed to clarify the role of DLCO as a potential tool in monitoring childhood asthma.

Evaluation of association between exercise-induced bronchoconstriction and childhood asthma control test questionnaire scores in children.

OBJECTIVE: Asthma control represents a major challenge in the management of asthmatic children; however, correct perception of control is poor. The aim of the study was to evaluate the association between subjective answers given to the Childhood Asthma Control Test (C-ACT) and objective evaluation of exercise-induced bronchonstriction (EIB) by standardized treadmill exercise challenge. METHODS: EIB was evaluated by standardized treadmill exercise challenge and related to C-ACT scores in 92 asthmatic children. RESULTS: Of the 92 studied children only six children had a concordance between a positive challenge test (ΔFEV1 ≥ 13%) and a positive response to the exercise-related issue of the C-ACT questionnaire (C-ACT total score ≤ 19). There was no significant association between the degree of EIB and the scores relative to the single question on exercise-related problems while a significant association was found when considering the whole questionnaire with C-ACT total score > 19 (r = -0.40, P < 0.001). The two single questions showing a significant association were those focusing on nocturnal asthma. The areas under the ROC curve (AUC) for the sum of the scores of these questions in relationship to a positive response to the exercise test was 0.74. The AUC of the C-ACT total score was 0.76 and 0.55 for the specific question on EIB related problems. CONCLUSION: The discrimination power of the C-ACT total score in relationship to EIB was moderately good, and C-ACT questionnaire was capable of correctly predicting the absence of EIB in children reporting a global score > 19. However, direct questions on EIB are associated with a high number of false positive and negative responses; better associations are found questioning on the presence on nocturnal symptoms.

Time-effect of montelukast on protection against exercise-induced bronchoconstriction.

INTRODUCTION: Montelukast has been proven to assure a protective effect against exercise-induced bronchoconstriction. AIM: To verify exactly when montelukast begins protection in asthmatic children by evaluating different time intervals between dosing and challenge. METHODS: In a double blind, placebo-controlled, three day doses, crossover study, patients were randomized to receive in sequence treatment with either a placebo or montelukast and assigned to one of seven groups that were tested 1, 2, 3, 4, 5, 6 and 8 h after drug administration, respectively. For each group, the exercise challenge was always performed at the same hour on the first and third days of treatment. RESULTS: Sixty-nine asthmatic children took part in the study. On day 3, the mean FEV(1) % fall from baseline was 25.54 (95% CI = 21.63/29.46) and 14.89 (95% CI = 11.85/17.92) for the placebo and active drug (p < 0.05), respectively. On day 1, the mean fall of FEV(1) was 28.20 (95% CI = 24.46/31.94) and 19.01 (95% CI = 15.71/22.31) for the placebo and montelukast (p < 0.05), respectively. Clinical protection was achieved in 21 (30%) and 33 (48%) subjects by montelukast on the first and third days, respectively. CONCLUSIONS: Montelukast assured protection against exercise-induced bronchoconstriction from the first through the eighth hour from the first day of treatment. However, individual susceptibility to protection was evident since some individuals were not protected at any time. We conclude that in clinical use individual responses to the drug should be carefully evaluated in the follow-up management.

Immune regulatory cytokines in the milk of lactating women from farming and urban environments.

Children living on farms have fewer allergies. It is unclear whether breastfeeding in different environments contributes to preventing allergies by exposing offspring to different cytokines that can modulate immune responses. The aim of this study was to quantify and compare levels of Transforming Growth Factor-beta1 (TGF-beta1) and Interleukin-10 (IL-10) in the colostrum and mature milk of mothers living in towns at sea level (references) and mothers on farms. Milk samples were collected within 3 days postpartum (colostrum) and at the first month of the baby's life (mature milk). Sixty-nine reference mothers and 45 farm mothers participated in the study. TGF-beta1 concentrations were significantly higher both in the colostrum (p < 0.05) and in mature milk (p < 0.05) of farm mothers. In the reference mothers, a significant decrease in TGF-beta1 concentrations was observed between colostrum (650, range 0-8000 pg/ml) and mature milk (250, range 0-8000 pg/ml) (p < 0.05). In farm mothers, TGF-beta1 concentrations were 1102 pg/ml (range 0-14,500) in colostrum and remained high in mature milk (821 pg/ml, range 0-14,650). IL-10 concentrations were higher in the mature milk of farm mothers (p < 0.05). No significant differences in IL-10 were observed between colostrum and mature milk in the control group (15 pg/ml, range 0-1800, and 0 pg/ml, range 0-230) or in farm mothers (9.5 pg/ml, range 0-1775, and 14.2 pg/ml, range 0-930), respectively. Exposure to a farm environment is associated with higher concentrations of TGF-beta1 and IL-10 in breast milk when compared to exposure to an urban environment. Higher cytokine concentrations in breast milk may influence early modulation of the development of an immune response, leading to a reduced prevalence of allergy-related diseases in farm children.

Children with nocturnal asthma wheeze intermittently during sleep.

Nocturnal asthma indicates poor overall control of asthma and adversely affects the quality of life of the patient. The purpose of the present study was to compare the objective measurement of nocturnal wheeze with clinical state, recall of symptoms, and changes in lung function. Nine asthmatic children aged 9 to 16 years were followed with an asthma diary and diurnal measurement of peak flow for a week before the nocturnal study; all but two were apparently well controlled. Breath sounds were recorded and analyzed continuously overnight to quantify wheeze using a phonopneumography sensor attached over the trachea. The analytical system (PulmoTrack) utilized an algorithm to detect wheeze and reject interference. The wheeze rate (Tw/Ttot = duration of wheeze/duration of recording) was calculated minute by minute throughout the night. Recordings lasted over 8 hours and all but two children had wheeze lasting for a total time of between 11 and 87 minutes. The pattern of wheezing was very variable during sleep, with episodes of wheeze separated by periods of quiet breathing. There was no relationship between subjective perception of nocturnal asthma, forced expiratory volume in 1 s (FEV(1)) next morning, and the objective measurement of wheeze. Total overnight wheeze was significantly related to the total diary symptom score and to the (small) diurnal variability of peak expiratory flow (PEF). Four of the seven children with asthma who were apparently well controlled had considerable amounts of wheeze during the night that was episodic in nature and unrelated to conventional measures of lung function or nocturnal symptoms.