Sensitization to turnip rape and oilseed rape in children with atopic dermatitis: a case-control study.

Turnip rape and oilseed rape 2S albumins are new allergens in children with atopic dermatitis suspected for food allergy. We recently found that 11% (206/1887) of these children had a positive skin prick test to seeds of oilseed rape (Brassica napus) and/or turnip rape (Brassica rapa). In the present case-control study we examined how the children with atopic dermatitis sensitized to turnip rape and oilseed rape had been breast-fed and whether they had some common sensitization pattern to certain foods or pollens. A total of 64 children with atopic dermatitis and a positive skin prick test to turnip rape and/or oilseed rape (>or=5 mm) were examined. Sixty-four age- and sex-matched children with atopic dermatitis but negative skin prick tests to turnip rape and oilseed rape served as case controls. The turnip rape and/or oilseed rape sensitized children with atopic dermatitis had significantly more often positive skin prick tests reactions and IgE antibodies to various foods (cow's milk, egg, wheat, mustard; p < 0.01) and pollens (birch, timothy, mugwort; p < 0.01) than the control children. They had been exclusively breast-fed for a longer period (median 4 months; p < 0.05) and had more often associated asthma (36%) and allergic rhinitis (44%). Children with atopic dermatitis sensitized to oilseed rape and turnip rape had high frequency of associated sensitizations to all foods and pollens tested showing that oilseed plant sensitization affects especially atopic children who have been sensitized to multiple allergens.     

Sensitization and allergy to turnip rape: a comparison between the Finnish and French children with atopic dermatitis

Aim: Finnish children with atopic dermatitis (AD) are frequently sensitized and show positive food challenge to turnip rape. We examined whether French children are also allergic to this oilseed plant and whether mustard could be the cross-reacting allergen.
Methods: Turnip rape and mustard challenge was performed to 14 Finnish and 14 French children with atopic dermatitis and positive skin prick test to turnip rape. Specific IgE antibodies were measured by ImmunoCAP and enzyme-linked immunosorbent assay (ELISA).
Results: Open labial or oral challenge to turnip rape was positive in 14 (100%) Finnish and five (36%) French children and mustard challenge in five Finnish and five French children. IgE antibodies to oilseed rape and mustard were slightly more frequent in the Finnish (100% and 93%) than in the French (93% and 71%) children but rare (4%) in the 28 matched controls. The same findings were true for IgE antibodies to purified 2S albumin allergens, which showed similar cross-wise IgE inhibition patterns.
Conclusion: French children with atopic dermatitis show IgE antibodies to turnip rape, oilseed rape and mustard similarly to the Finnish children. 2S albumin allergens in the seeds of these plants are highly cross-reactive and therefore, they all could be important sensitizers in children with atopic dermatitis.     

Sensitization to food and airborne allergens in children with atopic dermatitis followed up to 7 years of age

Previously we investigated the eczema prognosis and the risk of developing allergic asthma and rhinitis in a cohort of 94 children with atopic dermatitis. In this second study on the same cohort we address the development of sensitization to foods and airborne allergens, risk factors and, the question whether children with atopic dermatitis who will not become sensitized can be recognized early. Children with atopic dermatitis were followed up regularly from infancy or early childhood to 7 years of age with clinical examination and blood sampling. After age 3, skin prick tests with inhalation allergens were performed yearly. In most children both clinical allergy and sensitization to egg and milk were transient but those to peanut were persistent. Eighty per cent of the children became sensitized to airborne allergens and 75% of them noticed symptoms when exposed. Heredity for atopy and eczema, sensitization to hen's egg, and early onset of eczema entailed an increased risk of becoming sensitized. Children never sensitized had late onset of eczema and less heredity for atopic disease but did not differ in other respects from the sensitized children.     

Does the severity of atopic dermatitis correlate with serum IgE levels?

Recent studies suggest an association between atopic phenotypes and serum IgE levels. In contrast to asthma, this association has not been proven for atopic dermatitis. For 345 children (mean age 2.9 years), we investigated a correlation of the severity of eczema (defined by SCORAD score) and serum IgE levels. Additionally, the data was analyzed for differences between children with high and low SCORAD quartile. Parameters such as genetic background, the prevalence of other atopic phenotypes such as bronchial asthma, allergic rhinoconjunctivitis, and allergic sensitization were recorded. Our results indicate a significant correlation between SCORAD and serum IgE levels (R = 0.31, p < 0.001), but the standard deviation was large. Children with atopic dermatitis showed a high prevalence of sensitization to foods independent of the IgE levels; children with high SCORAD levels showed a sensitization to aeroallergens significantly more often (p < 0.02). No differences were found in prevalences of atopic family background, or a number of additional atopic symptoms such as asthma and allergic rhinoconjunctivitis. These results suggest that serum IgE levels seem to correlate with the degree of eczema. Children with severe atopic dermatitis and high IgE levels are at risk for sensitization to food allergens and aeroallergens.     

High prevalence of aeroallergen sensitization among infants of atopic parents

OBJECTIVE: To present methodology to identify atopic parents and determine the prevalence of sensitization to 15 aeroallergens in their infant offspring. STUDY DESIGN: A birth cohort of infants was identified from birth records; an infant was enrolled if 1 of the parents reported allergy respiratory symptoms and had a positive skin prick test (SPT) to a common aeroallergen. At age 1 year, these infants were tested to the same aeroallergens. RESULTS: Of the 680 enrolled infants, 28.4% were SPT+ to 1 or more aeroallergens and/or food, and 18.0% were positive to 1 or more aeroallergens. By category of allergens, 9.7% were sensitized to pollens, 7.5% to molds, 4.3% to house dust mite and/or cockroach, and 3.4% to dog and/or cat. Of the infants who were positive to an aeroallergen, 65.7% remained positive at age 2 years. CONCLUSIONS: Infants born to atopic parents with percutaneous sensitization to aeroallergens are at increased risk for aeroallergen sensitization during infancy, which persists to age 2 years. These findings suggest that current clinical practices, which generally avoid skin testing before age 2 years, be reassessed in this population of high-risk children.     

The use of mutually exclusive categories for atopic sensitization: A contrasting effect for family size on house dust mite sensitization compared with ryegrass sensitization

Our aim was to examine the relative importance of family size on sensitization to two different allergens: ryegrass and house dust mite (HDM), using a mutually exclusive classification for allergen-specific sensitization. An 8-year follow-up birth cohort study of children born between 1988–89 was conducted. The follow-up sample consisted of 498 children residing in Northern Tasmania in 1997 (84% of eligible). Outcome measures included skin prick test (SPT) reaction to nine aeroallergens and parental questionnaire. Family size was defined as sibling number in 1997. Children with a positive SPT to either Der p or Der f house dust mite but not ryegrass were classified as HDM-exclusive (n = 84). Children with a positive SPT to ryegrass but not HDM were classified as ryegrass-exclusive (n = 43). Family size was associated with reduced ryegrass-exclusive sensitization [AOR 0.57 (0.39, 0.84) per increase in sibling number] but not HDM-exclusive sensitization [AOR 0.97 (0.77,1.23)]. The difference in the family size effect on these sensitization outcomes was significant (p = 0.02). Similarly, family size tended to be associated with reduced asthma among ryegrass-exclusive sensitized children [AOR 0.45 (0.18,1.12)] but not HDM-exclusive sensitized children [(AOR 1.46(0.80–2.65)]. Large family size was strongly associated with reduced sensitization for ryegrass allergens but not HDM allergens using mutually exclusive sensitization categories. If this difference is confirmed in other studies, the contrasting effect of family size may reflect differences between these allergens with regard to level or timing of early life exposure, differences in allergen -specific potentiation for sensitization or unidentified confounding. The use of mutually exclusive categories for allergen sensitization will assist future work on child atopic disease.     

Sensitization to food allergens in Iranian children with mild to moderate persistent asthma

Background

Asthma is the most common chronic respiratory disease in childhood. The clinical presentation of asthma may worsen after food allergen ingestion in sensitized patients. To avoid nonspecific dietary restrictions in children with asthma, laboratory-based advice about foods is potentially helpful. The purpose of this study was to determine food sensitization in children with asthma.

Methods

Seventy-nine children with mild to moderate persistent asthma were included in this study. Commercial food allergens including cow??s milk, egg white, almond, potato, and soybean were used in skin prick tests. Specific IgE to 20 common food allergens was also measured in serum.

Results

Twelve (15.2%) of the patients had a positive skin prick test to at least one of the five food extracts. Sensitization was detected by skin prick tests to cow??s milk and egg white (each 6.3%), almond (3.8%), potato (2.5%) and soybean (1.3%). Specific IgE levels ??0.35 kAU/L were detected in the serum of 47% of the children with asthma. The most common food allergens were cow??s milk (26.6%), hazelnuts (25.3%), wheat flour (15.2%) and egg white (12.6%). Patients with a history of at least one hospital admission due to asthma attack had a higher rate of sensitization to egg.

Conclusions

In our study, food sensitization was frequent in Iranian children with asthma. Although clinical food allergy could not be evaluated because food challenge tests were not used in our study, skin prick tests and serum-specific IgE to common food allergens might be helpful in identifying children with food sensitization.     

The prevalence of allergic diseases in an unselected group of 6-year-old children. The DARC birth cohort study

This study determines the prevalence of atopic dermatitis, asthma, rhinoconjunctivitis, food hypersensitivity and urticaria and the frequency of sensitization in children with and without clinical allergic disease. In an ongoing prospective non-interventional birth cohort study of 562 unselected children, 404 children were subjected to interview, clinical examination, lung function measurements and allergy testing at 6 yr of age. Sensitization measured by skin prick test (SPT) and specific immunoglobulin E (S-IgE) was determined for 24 different allergens. The 1-yr period prevalence of atopic dermatitis, asthma and rhinoconjunctivitis was 14.4%, 6.2% and 13.6%. 25.7% of the children suffered from at least one of the three diseases. The frequency of sensitization in children with no disease (controls), any allergic disease, atopic dermatitis, asthma and rhinoconjunctivitis was 17%, 45%, 47%, 56% and 55% (defined as SPT ≥3 mm and/or S-IgE ≥0.35 kU/l for at least one allergen). Symptoms were linked to sensitization for 44% in the asthma group and 42% in the rhinoconjunctivitis group, whereas sensitization could not be linked to worsening of the eczema in any cases of atopic dermatitis. Overlap between the three diseases was significantly more frequent in sensitized children than in non-sensitized (19/46 = 41% vs. 9/58 = 16%, p = 0.004). The prevalence of food hypersensitivity and urticaria was 1.2% and 5.4% respectively. In unselected 6 yr old children, approximately half of the children with atopic dermatitis, asthma or rhinoconjunctivitis are IgE-sensitized. Sensitization tends to link these diseases to each other.     

Cutaneous lymphocyte‐associated antigen expression in children with atopic dermatitis and non‐atopic healthy children

Cutaneous lymphocyte‐associated antigen (CLA) is a cell surface glycoprotein which has been implicated in the homing of lymphocytes to cutaneous sites. It is postulated to play an important role in T‐cell migration to skin in atopic dermatitis; however, the expression of CLA in both normal children and children with atopic dermatitis has not been extensively studied. If CLA expression on T cells were important in the traffic of lymphocytes to atopic dermatitis skin lesions, it might be expected that the proportion of CLA⁺ T cells in unstimulated peripheral blood from children with atopic dermatitis would be elevated. We have examined the proportion of CLA⁺ T cells in children with atopic dermatitis and non‐atopic age‐matched controls. The proportion of CLA⁺ T cells in non‐atopic children was highly associated with and increased with increasing age ( r  = 0.88, p < 0.001). There was no difference between the proportion of T cells expressing CLA in the unstimulated PBMC from children with severe or mild/moderate atopic dermatitis and age‐matched non‐atopic controls (p = 0.18, p = 0.3, respectively). Despite this, children with atopic dermatitis did show evidence of perturbation of CLA expression, as unlike the non‐atopic children the proportion of CLA⁺ T cells in the atopic children did not correlate with age. These findings suggest that while CLA expression may play a role in atopic dermatitis, other as yet undefined surface markers are likely to principally determine the migration of T cells to skin in atopic dermatitis.     

The association between early sensitization patterns and subsequent allergic disease. The DARC birth cohort study

Prevention of allergic diseases depends on early identification of clinical markers preceding such disorders. This study describes the natural course of sensitization as measured by skin prick test (SPT) and specific immunoglobulin E (S‐IgE) and analyses the association between early sensitization patterns and subsequent allergic disease at 6 yr of age. In an ongoing population‐based birth cohort study of 562 children, follow‐up visits were performed at 0, 3, 6, 9, 12, 18, 36, and 72 months. Visits included an interview, physical examination, SPTs, and S‐IgE measurements for 12 food and inhalant allergens. The frequency of S‐IgE sensitization to ≥1 inhalant allergen was constant from 0 to 6 months (9–10%), decreased at 12–18 months before increasing from 36 months onwards. S‐IgE sensitization to at least one food allergen remained constant from 0 to 6 yr. SPT sensitization to food and inhalant allergens appeared from 3 and 12 months, respectively. Early food sensitization (S‐IgE) between 3 and 18 months was found to be significantly (p < 0.05) associated with atopic dermatitis (OR: 4.0 [1.6–9.9]) and asthma (OR 4.0 [1.1–12.5]) at the age of 6 yr. Children with atopic dermatitis, asthma, or rhinoconjunctivitis, and sensitization at 6 yr, were sensitized to food allergens to a large extent (53%, 42%, and 47%, respectively) already at 6 months. Early inhalant sensitization (S‐IgE) did not increase the risk of later allergic disease. Early atopic dermatitis (0–18 months) was also highly associated with subsequent allergic disease. Children with early food sensitization and/or atopic dermatitis would be a proper target group for future interventional studies.     

Wheezing requiring hospitalization in early childhood: Predictive factors for asthma in a six-year follow-up

Although asthma is common after wheezing in early childhood, the risk factors for and the prevention of later asthma are poorly understood. During the present follow-up study, a range of possible predictive factors for school-age asthma was evaluated. The study group consisted of 82 children hospitalized for wheezing at age < 2 years in 1992–93. The baseline data were collected on entry to the study. In 1999, the children were re-examined at the median age of 7.2 years. A structured questionnaire was applied to chart the symptoms suggestive of asthma, and the children were examined clinically. An exercise challenge test, as well as skin prick tests (SPT) to common inhalant allergens, was performed. Asthma was present in 33 (40%) children, 30 (91%) having continuous medication for asthma. The significant asthma-predictive factors, present on entry to the study, were blood eosinophilia (p = 0.0008), atopic dermatitis (p = 0.0089), elevated total serum immunoglobulin E (IgE) (p = 0.0452), and a history of earlier episodes of wheezing in infancy (p = 0.0468). SPT positivity in early childhood was also associated with school-age asthma (p = 0.002). In contrast, respiratory syncytial virus (RSV) identification during the index episode of wheezing played a minor role as a predictive factor for asthma. In conclusion, if hospitalization for wheezing occurs in infancy, more than every third child will suffer from asthma at early school age; the risk is significantly increased with recurrent wheezing in infancy and the development of allergic manifestations.     

Predictive features for persistence of atopic dermatitis in children

Allergen exposure plays an important role in atopic dermatitis (AD). Because immunological mechanisms underlying asthma and AD have great similarities, we evaluated whether features such as allergen sensitization, immune response, disease severity and duration or allergen exposure could be considered predictive for AD persistence. Seventy-one AD children (age range 14–158 months) were enrolled and followed for 3 consecutive years for AD severity using the SCORAD index (SI). At enrollment, reactivity to inhalant and food allergens using the skin prick test (SPT) and house dust mite (HDM) atopy patch test (APT), and HDM allergens in house dust were evaluated. After 3 years, 38 children outgrew their AD (AD^– group), while in 33 AD persisted (AD⁺ group). At enrollment, AD⁺ children had a higher SI, higher rate of positivity to SPT and APT for mites (p = 0.001), and higher environmental exposure to HDM allergens (p = 0.035). The AD⁺ children developed more respiratory symptoms in comparison to AD^– children (p < 0.001). None of the AD^– children presented APT positivity. In our study population, positivity of SPT and APT for HDM, environmental allergen exposure levels and severity of the disease at enrollment presented a significant predictive power towards AD persistence. Subjects with positive skin reactivity to HDM should be considered at risk of AD persistence and of possible development of allergic respiratory disorders.     

Total IgE in urban Black South African teenagers: The influence of atopy and helminth infection

Total IgE levels are usually elevated in allergic diseases, being highest in atopic eczema, followed by atopic asthma and allergic rhinitis. Genetic factors are believed to play a role in total IgE levels, with higher levels seen in Black African subjects. Total IgE is also raised in parasite infection. Thus, the higher total IgE levels in Black Africans could be because of environmental rather than genetic factors. Few studies have investigated the usefulness of total IgE levels in the evaluation of atopy in Black Africans. The objective of this study was to determine the total IgE levels in unselected urban Black African high school children and to correlate this with atopy and ascaris sensitization. Atopic status was assessed by means of specific allergen sensitization (skin prick tests to eight inhalant and four food allergens), self-reported asthma and bronchial hyper-responsiveness measured by methacholine challenge. Ascaris sensitization was assessed by means of ascaris IgE measured by CAP-RAST. Total IgE levels were markedly skewed toward the left and were not distributed in a Gaussian or a log-normal distribution. Skin prick tests were positive for aeroallergens in 32.3% of subjects. Thirty four percent had elevated ascaris IgE. Total IgE was higher in atopic vs. non-atopic subjects and correlated with the number of positive skin prick tests, self-reported asthma and bronchial hyper-responsiveness. Subjects without allergy (or) atopy had a median total IgE of 80–90 kU/I. In addition total IgE correlated with ascaris IgE. Subjects with no ascaris sensitization had median total IgE of 77.1 kU/l. Subjects with neither atopy/asthma nor ascaris sensitisation had a median total IgE of 69.9 kU/I, similar to the levels seen in people of other genetic origins. This study suggests that helminthic infection rather than genetic differences, may be the major determining factor of IgE levels in certain populations.     

Determinants of atopic sensitization in Turkish school children: Effects of pre- and post-natal events and maternal atopy

Emergence of new environmental risk factors, and/or loss of protective factors of a traditional lifestyle may explain the increase, or variations in prevalence of allergic diseases. The aim of this study was to delineate the prevalence and spectrum of, and to reveal the causal and/or protective factors for atopic sensitization among a heterogenous cohort of Turkish children, for the first time in our country. The study design adhered to International Study of Asthma and Allergies in Childhood (ISAAC) phase II protocol. A self‐administered parental questionnaire about demographic characteristics and detailed risk factors, and skin‐prick test with 13 allergens were employed in a clustered random sample of 8–11‐yr‐old Turkish school children. Atopy was defined as the presence of at least one positive skin reaction to any allergen tested. The association between a total of 78 risk factors and different aspects of atopy were analyzed in 1144 children with multivariate logistic regression analysis. The overall prevalence of atopy was 20.6%. Most common sensitizations were to grass pollens, Dermatophagoides pteronyssinus and Blatella germanica. Day care attendance, high paternal education level, male gender and maternal asthma were significant risk factors for atopy. Breastfeeding more than 6 months (compared with 0–6 months), maternal smoking during pregnancy and a birth weight under 2500 g were inversely related to (or protective factors for) atopic sensitization. Maternal atopic disease had significant effects on risk factors pattern. In children with a maternal atopy history a low birth weight, day care attendance and maternal smoking during the first year of life independently increased the risk of atopic sensitization. Gender, breastfeeding and paternal education did not show any association with atopy in this group of children. A history of measles and low gestational age were significant protective factors for mite sensitization. This study showed that children of atopic mothers showed a different profile of risk factors associated with atopic sensitization, when compared with other children. Prenatal and early childhood events had important associations with atopic sensitization.     

IgE antibody responses in young children with atopic dermatitis

In 2184 young children aged 13–24 months with atopic dermatitis (SCORAD 5–59) serum IgE antibodies to a standard panel of food and inhalant allergens were assayed. The frequency of positive IgE responses (>0.35 kU/l) increased with greater severity of skin disease. A significant minority of infants had levels of IgE antibody to foods to suggest they were at risk of acute reaction to those foods (7% to hen's egg, 3% to cow's milk, 4% to peanut). Our findings indicate that the frequency of positive IgE responses is related to disease severity and suggest that differences in the time course of the development of IgE responses to food, which are at maximum prevalence within the first year of life, while inhalant allergies, are still developing between 1 and 2 yr and beyond.     

The association of atopic dermatitis in infancy with immunoglobulin E food sensitization

OBJECTIVE: To prospectively investigate the association of high levels of immunoglobulin E (IgE) sensitization to foods and the presence of atopic dermatitis (judged by reported topical steroid use during the first 16 months of life) in a birth cohort of 620 Australian children "at risk" of allergic disease because of family history. RESULTS: A total of 559 of the children in the cohort were fully evaluated, and the cumulative prevalence of atopic dermatitis was 24%. More children in the cohort who had atopic dermatitis had strongly positive skin test results (> or = 4+, histamine equivalent units, > or = approximately 6-mm wheal), consistent with IgE food sensitization to either cow's milk, egg, or peanut at 6 months (22% vs 5%, chi(2) = 35; P < 10(-6)) and at 12 months (36% vs 11%, chi(2) = 41; P < 10(-6)) than those without atopic dermatitis. The calculated attributable risk percent for IgE food sensitization as a cause of atopic dermatitis was 65% and 64% at these times. In a separate group of infants with severe atopic dermatitis, the equivalent rates of IgE food sensitization at 6 months was 83% and at 12 months, 65%. CONCLUSION: IgE food sensitization is a major risk factor for the presence of atopic dermatitis in infancy.     

Frequent IgE sensitization to latex, cow's milk, and egg in children with short bowel syndrome

Children with short bowel syndrome (SBS) undergo frequent operations, so they are at risk for sensitizing to latex. There have been isolated reports of sensitization to food in these children. In a cross-sectional study, we assessed sensitization to latex, cow's milk, and egg with skin prick tests (SPT) and serum-specific immunoglobulin E (IgE) in 14 children with SBS. Data were collected about the number of operations with latex devices, serum total IgE, and history of feeding with milk formula. Ten children were sensitized to latex (specific IgE median: 6.7 kU/l, range: 0.5–33). Compared with those non-sensitized, sensitized children had significantly (p < 0.05) higher levels of serum total IgE in z-units (mean rank 3.25 vs. 9.2, respectively), and more operations with latex devices (mean rank 3.75 vs. 9). Eight children were sensitized to cow's milk, one with only positive SPT, the other seven with serum-specific IgE (median: 3.5, range: 0.5–21.1 kU/l), and five to egg (specific IgE median: 0.68, range: 0.58–2.17 kU/l). Except for some isolated days with cow's milk formula, the children had been initially fed with a diet without intact cow's milk proteins. Sensitization to latex, cow's milk, and egg is very frequent in children with SBS. They should be treated in a latex-free environment since the very early stages of the disease, and should be routinely studied regarding food sensitization, as this might contribute as an added factor in the chronic diarrhea of these patients.     

High prevalence of allergic diseases and sensitization in a low allergen country

BACKGROUND: The prevalence of adult atopic diseases in Iceland is lower than in other West European countries, despite an affluent lifestyle, but limited data are available on children. The main aim of this study was to investigate the prevalence of atopic diseases and sensitivity to common allergens in 10- to 11-year-old Icelandic schoolchildren as part of phase II of the International Study of Asthma and Allergies in Children (ISAAC). METHODS: Nine hundred and forty-six children and their parents answered a questionnaire about atopic diseases. Skin prick tests with six allergens were performed on 773 children and they were examined for signs of atopic dermatitis (AD). RESULTS: The 12-month prevalence of allergic rhinoconjunctivitis and asthma was 11.5% and 8.9% respectively. The reported prevalence of AD was 27%, but only 9.2% had signs when inspected. A positive skin prick test (SPT) was found in 24.4% of the children, that is 18.8% to grass, 12.9% to cat, 3.6% to trees, 3.0% to Dermatophagoides pteronyssinus, 1.4% to D. farinae and 0.5% to Alternaria. CONCLUSION: The high prevalence of atopic diseases in children at 10-11 years is surprising, as the prevalence in adults is low in Iceland. The findings resemble those in developing countries. Iceland has had an affluent lifestyle for a considerable time, but the absence of dust mites, low pet ownership and relatively low pollen counts in the country raise doubts about the role of exposure levels in the development of sensitization and atopic diseases.     

Atopic dermatitis: clinical relevance of food hypersensitivity reactions

Forty-six patients with atopic dermatitis ranging from mild to severe were evaluated for food hypersensitivity with double-blind placebo-controlled food challenges. Twenty-eight (61%) patients had a positive prick skin reaction to one of the foods tested. Sixty-five food challenges were performed; 27 (42%) were interpreted as positive in 15 (33%) patients. Egg, milk, and peanut accounted for 78% of the positive reactions. As in previous studies, patients developed skin (96%), respiratory (52%), or gastrointestinal (30%) symptoms during the challenge. These studies indicate that children who have atopic dermatitis unresponsive to routine therapy or who continue to need daily treatment after several months would benefit from evaluation for food hypersensitivity.     

Skin‐prick test findings in atopic asthmatic children: A follow‐up study from childhood to puberty

In a prospective cohort study we investigated the course of allergic sensitization from childhood to puberty in a group of children with atopic asthma. An attempt was made to correlate the findings with the persistence of asthma. A total of 150 children with atopic asthma established at 7 years of age were evaluated when 8–10 years of age. A battery of skin‐prick tests (SPTs) to common environmental allergens, a detailed clinical history for asthma severity classification, and spirometric analyses, were performed. In 127 of these children a re‐evaluation was performed at puberty. A variety of statistical methods were used to analyze the results regarding changes in skin test reactivity to individual aeroallergens and atopic index (degree of atopy), as well as to determine any correlation between these changes and the persistence of asthma in puberty. A wide spectrum of modification in skin reactivity to common environmental allergens was observed, including the complete loss of sensitization to some allergens or the development of a new one to others. Specifically, 34% of asthmatic children sensitive to Dermatophagoides pteronyssinus and 52.7% sensitive to cat lost their sensitivity in puberty, while only 7.5% and 11.1%, respectively, became sensitized (p = 0.03 and p = 0.001, respectively). In contrast, regarding pollen sensitivity, 30.2% and 24% of asthmatic children became sensitive in puberty to olive pollen and grasses mix, respectively, and only 11.7% and 12.5%, respectively, lost their sensitivity to these allergens (p = 0.04). No correlation was shown between the skin test reactivity changes to individual allergens and the persistence of asthma, but a significant correlation was found between atopic index to indoor allergens in childhood and the persistence of asthma at puberty (p = 0.04). Interestingly, multi‐sensitivity to allergens (≥ 4 allergens) in childhood was also found to correlate with the persistence of asthma at puberty [p = 0.05, odds ratio (OR) = 2.65, 95% confidence interval (CI) 1.2–7.2]. Our findings indicate that significant modification of skin reactivity to common environmental allergens in atopic children with asthma in puberty can occur. However, no association between these changes and the persistence of asthma could be demonstrated, although children with indoor allergic sensitization and multi‐reactivity were found to have a higher probability of maintaining their asthma in puberty.