Background: House dust mite (HDM) allergy is a frequent cause of allergic asthma in children. Reduction of exposure seems to be the most logical way to treat these patients. Objective: Our aim was to ...investigate whether mattress and pillow encasings resulted in an effective long-term control of HDM allergen levels, thereby reducing the need for asthma medication in children with asthma and HDM allergy. Methods: In a prospective, double-blind, placebo-controlled study 60 children (age range, 6-15 years) with asthma and HDM allergy were randomized to active (allergy control) or placebo mattress and pillow encasings. After a 2-week baseline period, follow-up was performed every 3 months for 1 year. During the entire study period, the dose of inhaled steroids was tapered off to the lowest effective dose according to well-defined criteria. Results: Fifty-two patients completed the trial, and 5 were excluded, leaving data from 47 children (26 in the active treatment group and 21 in the placebo group) for analysis. A significant perennial reduction in HDM allergen concentrations was seen only for the active treatment group. Also, a significant decrease in the dose of inhaled steroids (mean, 408 to 227 μg/d; P < .001) was found for the active treatment group only, with significant differences between groups after 9 and 12 months. After 1 year, the dose of inhaled steroids was reduced by at least 50% in significantly more children in the active treatment group than in the placebo group (73% vs 24%, P < .01). Conclusion: Encasing of mattresses and pillows resulted in a significant long-term reduction in HDM allergen concentrations in mattresses and in the need for inhaled steroids in children with asthma and HDM allergy. (J Allergy Clin Immunol 2003;111:169-76.)
The aim of this study was to compare the allergy‐preventive effect of a partially hydrolyzed formula with two extensively hydrolyzed formulas, in infants with a high risk for development of allergic ...disease. High‐risk infants from four Danish centres were included in the period from June 1994 to July 1995. Five‐hundred and ninety‐five high‐risk infants were identified. High‐risk infants were defined as having bi‐parental atopy, or a single atopic first‐degree relative combined with cord blood immunoglobulin E (IgE) ≥ 0.3 kU/l. At birth all infants were randomized to one of three different blinded formulas. All mothers had unrestricted diets during pregnancy and lactation and were encouraged to breast‐feed exclusively. If breast‐feeding was insufficient, one of the three formulas, according to randomization, was given during the first 4 months. It was recommended not to introduce cow's milk, cow's milk products, and solid foods until the age of 4 months. After the age of 4 months a normal unrestricted diet and conventional cow's milk‐based formula were given when needed. All infants were followed‐up prospectively with interview and physical examination at the age of 6, 12, and 18 months, and if any possible atopic symptoms were reported. If food allergy was suspected, controlled elimination/challenge procedures were performed in a hospital setting. Of 550 infants included in the study, 514 were seen at all visits and 36 were excluded owing to non‐compliance. Of 478 infants who completed the study, 232 were exclusively breast‐fed, 79 received an extensively hydrolyzed casein formula (Nutramigen), 82 an extensively hydrolyzed whey formula (Profylac), and 85 a partially hydrolyzed whey formula (Nan HA), during the first 4 months of life. These four groups were identical in regard to atopic predisposition, cord blood IgE, birthplace, and gender. Exclusively breast‐fed children were exposed less to tobacco smoke and pets at home and belonged to higher social classes, whereas the three formula groups were identical concerning environmental factors. The frequency of breast‐feeding was high; only eight (2%) children were not breast‐fed at all. The three formula groups were identical in regard to duration of breast‐feeding and age at introduction of formula and solid foods. No significant differences were found in the three groups of infants receiving formula milk regarding the cumulative incidence of atopic dermatitis or respiratory symptoms. The cumulative incidence of parental‐reported cow's milk allergy was significantly higher in children fed partially hydrolyzed formula (Nan HA) compared with extensively hydrolyzed formula (Nutramigen or Profylac) at 12 and 18 months (NanHA, 7.1%; Nutramigen, 2.5%; Profylac, 0%; p = 0.033). The cumulative incidence of confirmed cow's milk allergy was 1.3% (three of 232) in exclusively breast‐fed infants, 0.6% (one of 161) in infants fed extensively hydrolyzed formula (Nutramigen or Profylac), and 4.7% (four of 85) in infants fed partially hydrolyzed formula (Nan HA). Partially hydrolyzed formula was found to be less effective than extensively hydrolyzed formula in preventing cow's milk allergy, 0.6% vs. 4.7% (p = 0.05), but because of the small number of cases the results should be interpreted with caution. Compared with other similar studies the frequency of atopic symptoms was low, even though the dietetic intervention did not include either maternal diet during lactation or dietary restrictions to the children after the age of 4 months.
A new lancet with a point length of 1.0 mm suitable for skin prick testing is described. The weal reactions appearing after the use of histamine chloride 1 mg/ml and an extract of Phleum pratense in ...a 1 HEP concentration (1 histamine equivalent prick) prove suitable as regards size and reproducibility compared with the reactions produced by a more conventional prick test method. The new lancet simplifies the prick test procedure and does not require as much experience as do needles and longer lancets.
A cohort of 1,749 newborns in the municipality of Odense were followed prospectively for the development of cow's milk allergy (CMA) during their first year of life. Altogether 39 fulfilled the ...criteria for CMA (2.2%). Out of the 39 infants, 17 developed symptoms of CMA during breast-feeding, in all cases before the age of 3 months. Nine of these were solely breast-fed at the time of diagnosis, giving a one year incidence of CMA in exclusively breast-fed infants of 0.5% (9/1,749) in a study population with a frequency of exclusive breast-feeding of 52% at 3 months of age. None of the infants had signs of CMA in the neonatal period. Review of records from the newborn nursery revealed that all 9 infants had been exposed to cow's milk formula in amounts corresponding to approximately 0.4-3.0 g of beta-lactoglobulin (BLG) during the first three days of life. Human milk samples were analyzed by enzyme-linked immunosorbent assay (ELISA) for the content of bovine BLG. Detectable amounts (0.5-45 ng/ml) were found in 3/9 samples of human milk against which the infants reacted clinically. Analysis of the size distribution by high pressure liquid gel permeation chromatography in combination with ELISA indicated a molecular weight of BLG corresponding to that of monomeric BLG (18 kD). Possibly early inadvertent and occasional exposure to cow's milk proteins may initiate sensitization in predisposed neonates. Subsequent exposure to minute amounts of bovine milk proteins in human milk may act as booster doses eliciting allergic reactions.
The prevalence of intolerance to food additives was assessed in a group of unselected school children aged 5-16 years. A study group of 271 children was selected on the basis of the results of a ...questionnaire on atopic disease answered by 4,274 (86%) school children in the municipality of Viborg, Denmark. The children in the study group followed an elimination diet for two weeks before they were challenged with a mixture of food preservatives, colourings and flavours. The challenge was open and the additives were prepared as a fizzy lemonade. If the open challenge was positive, a double-blind placebo controlled challenge with gelatine capsules was performed. The study included 281 children, 10 were excluded, and the remaining 271 children were given the open challenge (98 healthy controls and 173 with atopic symptoms). The open challenge was negative in all 98 healthy control children who had not reported any atopic symptoms. Of the 173 children reporting present or previous atopic disease 17 had a positive open challenge. Of these 17 children 1 experienced gastrointestinal symptoms, 13 reacted with aggravation of atopic eczema, and 3 with urticaria. Twelve of these 17 children went through the double-blind challenge which was positive in 6 cases. Five of these 6 children had positive reactions to synthetic colourings and 1 to citric acid. No serious reactions were seen. Based upon calculations of the results from this study and an earlier multi-center study in children referred to hospital clinics, the prevalence of intolerance to food additives in school children is estimated to be 1-2%.
As a result of a 1990 survey by questionnaire, the symptoms of atopy among all 4,952 school children aged 5 to 16 years in the municipal district of Viborg, Denmark, were registered. Random checks, ...made among children who were recorded as having symptoms, and others who were recorded as having none, accorded well with the information supplied by the parents about symptoms and the clinical diagnosis of a specialist; 10.5% of all school children had rhinitis, 7% had atopic eczema, 3.2% had urticaria and 4.5% had asthma; 1/4 of all those questioned had shown symptoms within the last year, and a further 13% of all the children were reported as having had atopic symptoms that had disappeared more than a year previously. Of the children showing symptoms within the last year before the survey, 2/3 had gone to a doctor. Of the children with present symptoms, largely asthma, 1/4 had been referred to a hospital allergy clinic. For 1/3 of the children with present symptoms, these had led to no contact with a doctor. Of the cases with present symptoms, 6.5% had had contact with natural healers or chiropractors. Rhinitis and asthma were most frequent among boys, while atopic eczema was most frequent among girls. For both sexes, the frequency of rhinitis increased during their years at school, while the frequency of skin symptoms fell.
In a double blind 3-year prospective study 40 grass pollen allergic patients were allocated to specific immunotherapy (hyposensitization) with two timothy major allergens, 19, 25, or partially ...purified timothy extract. The extracts were biologically standardized and coupled to aluminium hydroxide for treatment. Efficacy of hyposensitization was evaluated by titrated nasal provocations and skin prick tests with the two treatment extracts and a five-gram mixture. The threshold dose for skin prick test (skin thresholds) produced reactions identical to histamine chloride 5.43 mmol/l and the threshold dose for nasal provocations (nasal thresholds) produced two of the three reactions: at least 0.5 ml of nasal secretion, at least five sneezes, and/or at least a 20% fall in nasal peak flow. Nasal thresholds showed highest efficacy from partially purified timothy extract but equal protection against timothy and the five-grass mixture. Nasal thresholds of 14 untreated patients corresponded to treatment with the two major allergens. Changes in skin and nasal thresholds after 12 and after 54 weeks of treatment predicted the severity of hay fever. Increase in nasal thresholds coincided with a marked effect on asthma. Nasal thresholds below 1 HEP before treatment predicted major systemic side effects.
Perennial hyposensitization with a partially purified timothy extract resulted in a statistically significantly higher degree of clinical protection than treatment with the two timothy major ...allergens (Nos. 19 and 25) and protected better from the second--than during the first grass pollen season. The extracts were standardized biologically and adsorbed to aluminium hydroxide for administration. The therapy had a more beneficial influence on sneezing than on rhinorrhoea and blockage of nasal airways, and an excellent effect on grass pollen asthma was obtained with the partially purified timothy extract. Associated birch pollen allergy was not influenced by hyposensitization with grass pollen.
In a 3-year prospective double blind study, grass pollen allergic patients were allocated to perennial hyposensitization with the timothy major allergens Nos. 19 and 25 (2-component extract) or a ...20-component timothy extract. The extracts were biologically standardized and adsorbed to aluminium hydroxide for treatment. Systemic side effects (SSE) had début after 1 1/2-5 h and lasted without treatment 1/2-10 h. Treatment with the 2-component extract showed preponderance of minor SSE (arthralgia, rhinitis, tiredness, headache, conjunctivitis, nausea, flu-like symptoms), but major SSE (urticaria, angioedema, asthma) were equally distributed between treatment with the two timothy extracts. Major SSE complicated the treatment before the first grass pollen season in 33% of the patients vs. only in 3% during the subsequent perennial therapy, and developed (92%) at high single dose of greater than or equal to 1,000 biological units. The majority (69%) were later able to reach the same or higher dose without relapse. Most (62%) patients with major SSE were predicted by high nasal sensitivity before treatment. Only 18% of the patients had immediate local skin reactions of greater than or equal to 2 cm, but delayed local side effects of greater than or equal to 10 cm were recorded in 70%. Immediate skin reactions did not correlate with delayed skin reactions or with SSE, but delayed local side effects tended towards negative correlation with major SSE. A mean area reduction of 50% of the delayed skin reactions was recorded by repetition of a single dose. Subcutaneous nodules appeared at single doses of greater than or equal to 5,000 biological units. Only 5% of the patients contracted nodules during initial preseasonal therapy compared with 38% during subsequent perennial dosage. The nodules contained typical benign granulomas, and the frequency in the two groups was proportionate to the quantity of aluminium in the two extracts.
