M. Moseler

Sensitization to four common inhalant allergens within 302 nuclear families

The coincidence of allergic sensitization was investigated in 302 school‐aged children and their parents. Specific sensitization to four common inhalant allergens (grass and birch pollens, cat dander, Dermatophagoides pteronyssinus) was ascertained by means of skin‐prick tests (SPT) carried out on the complete family unit at the beginning of a 22‐month follow‐up period. The same test procedure was then repeated on the children twice at 11‐month intervals to provide cumulative prevalences of sensitization. A clinical history of atopy in the children (hay fever or asthma; n= 47), which was derived from an interview, is associated with sensitization (positive SPT in 89%). For three allergens (grass and birch pollens, cat dander) sensitization occurs significantly more frequently in the children of mothers who are sensitized to the same allergen (odds‐ratios (ORs), 2.5–4.1). Additionally, in three of the four explanatory models related to a single antigen, maternal sensitization to one of the complementary allergens is of importance (ORs, 2.7–3.7). In contrast to this finding, none of the paternal sensitizations has statistical significance. Based on a reaction to at least one of the four allergens, the childs relative risk to be sensitized is increased in case of maternal (OR, 2.88; P= 0.001) but not of paternal (OR, 1.06; P= 0.83) sensitization. In conclusion, our data indicate that the maternal status is more predictive than that of the father with regard to the childs risk of sensitization.

Allergen‐specific T cell reactivity in cord blood: the influence of maternal cytokine production

Background Successful pregnancy is dependent upon T helper (Th)2‐type‐dominated immunological responsiveness in gestation‐associated compartments.

Longitudinal variability of skin prick test results

The skin prick test (SPT) is a commonly used procedure for assessing a specific sensitization. The longitudinal variability of test results is of interest for clinical as well as epidemiological investigations. The sensitization to four common aeroallergens (grass pollen, birch pollen, Dermatophagoides pteronyssinus, cat dander) is investigated within the framework of three consecutive SPTs at 11‐month intervals for a population of 587 schoolchildren. The prevalence of sensitization based on a weal diameter of at least 2 mm was between 12.9% (cat dander) and 23.9% (grass pollen) in the initial testing. The positive predictive values of the initial SPT were between 75.3% (birch pollen) and 88.2% (cat dander) for the two subsequent SPTs. In the case of initially negative tests with positive second and third SPTs the incidence ranged between 3.2% (cat dander) and 4.3% (birch pollen) per year. A clear increase in the intensity of reaction in subsequent tests was observed in a number of probands testing positively in the initial SPT. In conclusion, our data indicate a high long‐term stability of a specific sensitization to aeroallergens in SPT.

Circadian Variation of Exhaled Nitric Oxide and Urinary Eosinophil Protein X in Asthmatic and Healthy Children

Asthmatic symptoms and the frequency of admissions to hospital because of acute asthma tend to increase in the early morning hours, and it is therefore possible that airway inflammation increases during the night. To elucidate the hypothetical circadian variation of airway inflammation, we measured concentrations of exhaled nitric oxide (FeNo), urinary eosinophil protein X excretion (EPX), and forced expiratory volume in the first second (FEV1) in 20 asthmatic and 6 nonatopic nonasthmatic children every 3 h during a 21-h period. Compared with control subjects, asthmatic subjects had higher FeNo (median, 22.7 versus 10.3 ppb, p = 0.016) and lower FEV1 % predicted (median, 91.0 versus 101.9%, p = 0.045), but did not differ significantly in EPX (median, 153.8 versus 148.7 μg/mmol creatinine, p = 0.83) at 7 AM. However, differences in gender and age do not allow direct comparisons between asthmatic and control children. FeNo and EPX demonstrated a cosinelike circadian rhythm (log FeNo, p = 0.0001; log EPX, p = 0.0001) with lowest levels at 7 PM and highest at 7 AM. This was also the case for FEV1 % (p = 0.01). No difference in the amplitude of circadian rhythm was observed between asthmatic and healthy control children for log FeNo (p = 0.35), log EPX (p = 0.57), and FEV1 % (p = 0.17). A stratified analysis showed a significant circadian rhythm in the control group for log FeNo (p = 0.014) and log EPX (p = 0.0001). Our results therefore suggest a circadian rhythm of inflammatory markers, which peaks in the early morning. Rhythmicity of EPX excretion and FeNo in healthy children suggests a physiologic mechanism; however, pathologic effects during the night might occur under conditions of asthma-specific inflammation.

High interleukin-13 production by phytohaemagglutinin- and Der p 1-stimulated cord blood mononuclear cells is associated with the subsequent development of atopic dermatitis at the age of 3 years

Objective The aim of our study was to conduct a prospective investigation into the potential association of cord blood proliferative response and cytokine production in response to various stimuli on the development of atopic dermatitis (AD) at the age of 3 years.

Pulmonary function in children of school age is related to the number of siblings in their family

It has been suggested that the number of siblings in a family is a surrogate variable for exposure to early infections. Since there may be an association between early respiratory infections and impaired lung function in later life, the aim of this study was to elucidate the relationship between the number of siblings and pulmonary function. We analyzed pulmonary function data from 677 schoolchildren living in 431 nuclear families.

The most common phenotypes of sensitization to inhalant allergens in childhood

Background Atopic individuals are frequently sensitized to a limited number of certain allergens, although most of them are exposed to multiple inhalant allergens in daily life. Objective We investigated the hypothesis that observed common patterns of sensitization might occur with similar frequency within two independent study populations of school‐children.

Preventive effect of 2 and 10 mg of sodium cromoglycate on exercise-induced bronchoconstriction

Abstract This double-blind, randomised and cross-over study was designed to compare the preventive effect against exercise-induced bronchoconstriction (EIB), defined as the percentage decrease in FEV1≥15% after 6 min of exercise, of 2 mg and 10 mg of sodium cromoglycate (SCG), administered through a metered dose inhaler via spacer, in asthmatic children. Each of the 30 subject (age 11.6 ± 3.2 years) was tested on five occasions. For inclusion, EIB in test1 was required. In tests 2 to 5, all subjects inhaled 2 mg or 10 mg of SCG 20 min and 120 min before exercise in a randomised order. In order to assess excretion of eosinophil protein X (EPX) accompanying EIB, urine samples were collected before and after exercise. The mean percentage fall in FEV1 (±SD) in test 1 was 26.8 ± 9.8%. Inhalation of 2 mg and 10 mg of SCG 20 min before exercise provided a significant preventive effect in 83% and 77% and inhalation 120 min before exercise provided a preventive effect in 63% and 70%, respectively (n=30). Variance analysis did not reveal a statistically different absolute fall in FEV1 after exercise when both doses (120 min before exercise) were compared (P=0.356). In an unselected subgroup of 12 children, urinary EPX increased after the challenge without SCG premedication (test 1) (mean change: +48.7 μg/mmol creatinine, P=0.034), whereas no significant increase was found in case of SCG premedication (mean change in μg/mmol creatinine): 2 mg/20 min: +12.1; 2 mg/120 min: +8.5; 10 mg/20 min: −10.4 and 10 mg/120 min: −23.5; P > 0.1). Conclusion Administration of 10 mg of sodium cromoglycate is no more effective in preventing exercise-induced bronchoconstriction than 2 mg regardless of whether the medication is given 20 or 120 min before exercise. The preventive effect of sodium cromoglycate on exercise-induced bronchoconstriction in asthmatic children is associated with the inhibition of urinary eosinophil protein X excretion.

Mütterliches Alter und Anzahl der Geschwister Kombinierte Wirkung familiärer Risikofaktoren auf die allergische Sensibilisierung

ZusammenfassungFragestellung: Familiäre Risikofaktoren wie Anzahl der Geschwister und mütterliches Alter zum Zeitpunkt der Geburt scheinen neben der genetischen Disposition und Umwelteinflüssen eine Rolle in der Allergieentstehung zu spielen. Unklar ist, inwieweit mütterliches Alter und Anzahl der Geschwister als familiäre Risikofaktoren die Sensibilisierungshäufigkeit beeinflussen. Methode: In einer großen epidemiologischen Studie wurde bei 1470 von 2604 befragten Grundschülern die Bedeutung von Alter der Mutter und der Anzahl der Geschwister für die allergische Sensibilisierung analysiert. Die allergische Sensibilisierung wurde mittels Haut-Prick-Test mit 7 inhalativen Umweltallergenen erfaßt. Die Datenerhebung erfolgte mit Hilfe eines Fragebogens. Ergebnisse: Anhand der multiplen logistischen Regression [Odds-Ratio (OR), 95%-Konfidenzintervall (95% KI)] nahm das relative Risiko einer Sensibilisierung mit der Geschwisteranzahl ab (OR=0,8, 95% KI 0,7–0,9). Im Vergleich zu Kindern mit jüngeren Müttern (<21 Jahre bei der Geburt des Kindes) zeigte sich ein erhöhtes Sensibilisierungsrisiko für Kinder von Müttern, die älter als 21 Jahre waren (OR(21–30 Jahre)=1,9, 95% KI: 0,9–4,2 bzw. OR≥31 Jahre)=2,4, 95% KI: 1,1–5,2). Eine Unterteilung der Analyse nach dem Alter der Mutter ergab, daß das Sensibilisierungsrisiko von Kindern älterer Mütter (>30 Jahre) nicht mit der Geschwisteranzahl abnimmt (0, 1, 2, 3+ Geschwister: OR=1,0; 1,0; 1,1; 1,2), während dies bei Kindern jüngerer Mütter (≤30 Jahre) der Fall ist (0, 1, 2, 3+ Geschwister: OR=1,0; 0,9; 0,5; 0,4). Schlußfolgerung: Die Ergebnisse weisen darauf hin, daß das Sensibilisierungsrisiko nur dann mit steigender Geschwisterzahl absinkt, wenn die Mutter zum Geburtszeitpunkt jünger als 30 Jahre war. Falls in der Bevölkerung das durchschnittliche Alter der Mutter bei der Geburt des Kinds über Jahrzehnte hinweg ansteigt, könnte dies den sog. Geschwisterzahleffekt beeinflussen.SummaryIntroduction: The pathogenesis of allergic sensitization remains an unsolved mystery. Of considerable interest for this problem are epidemiological observations that maternal age and the number of siblings play an important role in the allergic diathesis. But little is known about the association between maternal age and number of siblings, and the prevalence of allergic sensitization. We hypothesized that despite the association of both factors, maternal age and the number of siblings are independent riks factors for allergic sensitization. Methods: Information was gathered from 2604 families of whom 1470 children 6 to 8 years of age were tested by means of a skin prick test with seven aeroallergens. Results: The risk of sensitization decreased by the increasing the number of siblings [Odds Ratio (OR) 0.8, 95% Confidence intervall (95% CI) 0.7–0.9]. The risk of sensitization increased if the mothers were older than 21 years (OR(21–30 years)=1.9; 95% CI: 0.9–4.2; OR(≥31 years)= 2.4, 95% CI: 1.1–5.2). A stratification for maternal age showed that the number of siblings did not influence the prevalence of sensitization if the mothers were older than 30 years at birth of their child (0, 1, 2, 3, 3+ siblings: OR=1.0, 1.0, 1.1, 1.2), whereas the risk of sensitization decreased with the number of siblings if the mothers were younger than 30 years (0, 1, 2, 3, 3+ siblings: OR=1.0, 0.9, 0.5, 0.4) Conclusion: We confirm that there is an inverse relation between the number of siblings and sensitization in childhood. Our results suggest that the risk of allergic sensitization decreases with the number of siblings only if the mother is younger than 30 years at the child’s birth. Thus, an increase of maternal age at birth within a population could alter the so-called ’sibling effect’.