Is thrombopenia in cord blood indicative of intra-uterine sensitization?

The relation between platelet counts (PCT) and IgE was studied in cord blood from 136 European newborns. PCT was significantly lower (P = 0.0014) when cord-IgE was superior to 1.20 IU/ml (n = 29; 245,000/microliter) than when it was inferior to this value (n = 107; 284,080/microliter) which resulted in a significant negative Spearman rank correlation between PCT and cord-IgE (P = 0.002; rs = -0.25). A follow-up by questionnaire in 97 of the newborns revealed that those newborns who had developed definite atopy within 18 months of age had significantly (P = 0.002) lower PCT at birth (n = 8; 196,000/microliter) than those free of atopic symptoms (n = 61; 286,000/microliters). Further newborns to atopic mothers (n = 23; 245,000/microliters) had significantly (P = 0.014) lower PCT than newborns to non-atopic mothers (n = 74; 286,000/microliters). The lowest PCT was recorded when both the mother was atopic and the newborn had developed definite or probable atopy by the age of 18 months (n = 7; 175,000/microliters) as compared to atopy alone in mothers (n = 16; 276,000/microliters; P = 0.005), to atopy alone in infants (n = 9; 281,000/microliters; P = 0.005) and to non-atopic infants of non-atopic mothers (n = 65; 286,000/microliters; P = 0.0007). Significantly (P = 0.03) lower PCT amongst boys (n = 49; 259,000/microliters) compared with girls (n = 48; 294,000/microliters) was attributed to the higher incidence of elevated cord-IgE and infant atopy among boys.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cord blood IgE. II. Prediction of atopic disease

Screening of total IgE in 2814 cord blood samples was analysed by Phadebas IgE PRIST in 2 1-year birth cohorts (1983-1984 and 1985–1986) in Denmark ( n = 1189 + 1625). For follow-up we chose all infants with cord blood IgE ≥ 0.5 kU/1 and a randomly chosen group of the same size with cord blood IgE < 0.5 kU/1. A total of 762 infants were clinically evaluated at 18 months of age. A diagnosis of definite atopy, probable atopy or no atopy, including both IgE and non-IgE mediated disease was established. Applying different cord blood IgE cut-off values (0.3, 0.5, 0.8, 1.1) we did not find an excess of atopic infants among those with elevated cord blood IgE irrespective of the chosen cut-off value. Atopic predisposition or family history of atopic disease was defined as at least one parent or older siblitig with atopic disease. Significantly more infants with a family history developed atopy at 18 months. In the 2 series the positive predictive values of cord blood IgE≥0.5 were 43% and 46% and the sensitivities were 17% and 15%. The predictive values of having a family history were 48% and 44% and the sensitivities were 55% and 58%.
Clinical aspects
Cord blood IgE analysed by Phadebas IgE PRIST was a poor predictor of infants developing atopic disease before the age of 18 months.     

Cord blood IgE. III. Prediction of IgE high-response and allergy

Screening of total IgE in 2814 cord blood samples was analysed by Phadebas IgE PRIST in 2 1-year birth cohorts (1983–1984 and 1985–1986) in Denmark (n= 1189 + 1625). For follow-up we chose all infants with cord blood IgE≥0.5 kU/1 and a randomly chosen group of the same size with cord blood IgE < 0.5 kU/1. A total group of 762 infants were clinically evaluated at 18 months of age, and in 688 of these we evaluated total and specific IgE. A diagnosis of definite atopy, probable atopy or no atopy was established. In the present study we defined allergic disease as atopic disease combined with elevated total IgE. We found a statistically significant correlation between cord blood IgE and IgE at 18 months of age. Significantly more infants with elevated cord blood IgE had developed allergic disease at 18 months. A cut-off value of 0.3 kU/1 for cord blood IgE was superior to the originally suggested 0.5 kU/1. Significantly more infants with elevated cord blood IgE had developed specific IgE antibodies at 18 months. The most frequent specific IgE antibody was towards cow's milk. Specific IgE antibodies were very rarely found when total IgE was not elevated. A total IgE at the age of 18 months > 26 kU/1 could be regarded as elevated. With regard to allergic disease the positive predictive values of cord blood lgE≥0.3 kU/1 in the 2 series were 21 % and the corresponding sensitivities 67% and 46%, respectively. The risk of developing allergic disease was elevated with a factor 3 to 4 when cord blood IgE ≥ 0.3 kU/1. In a high-risk group based on atopic predisposition and elevated eord blood IgE ≥0.5 kU/1 the relative risk of allergic disease was 5, the predictive value of positive test 38%, the sensitivity 24% and the specificity 96%. Clinical aspects Cord blood IgE was a good predictor of allergic disease at the age of 18 months. A cord blood cut-off IgE value of 0.3 kU/l was superior to other cord blood IgE values with the Phadebas IgE PRIST method.     

Elevated concentrations of salivary secretory immunoglobulin A anti-cow's milk protein in newborns at risk of allergy

Secretory immunoglobulin A (SIgA) anti-casein and SIgA anti-beta-lactoglobulin (BLG) were determined in the saliva of 158 healthy mature infants at birth and in breast milk samples using a direct Elisa technique. IgG anti-casein and anti-BLG were measured in serum samples from mothers and newborns (cord blood). A high risk of allergy was defined in 66 infants who had cord blood (CB)-IgE levels greater than or equal to 0.9 IU/ml and/or parents with atopic diseases. Thirty infants had CB levels less than 0.9 IU/ml and parents without clinical symptoms of atopy but with elevated serum IgE concentrations or type I skin reactions to common allergens (low risk). Sixty-two infants had CB-IgE levels less than 0.9 IU/ml and healthy parents (no risk). The groups were matched for social status, smoking and dietary habits. SIgA anti-casein and anti-BLG were detected in all newborns. SIgA anti-casein was significantly higher (p less than 0.05) in high risk infants (medium 157; 50% confidence limits 45-270) than in no risk (48; 25-150) or low risk infants (43; 21-130). SIgA anti-casein values correlated with maternal allergy, maternal allergy plus CB-IgE, but not with paternal allergy. Breast milk SIgA anti-BLG was depressed (p less than 0.05) in mothers with manifest allergy compared to healthy mothers. Determination of salivary SIgA anti-casein may represent an additional screening method for early detection of infants with atopic disposition.     

Cord serum IgE: an insensitive method for prediction of atopy

Cord total serum IgE has been advocated as a screening test to detect infants at high risk of allergy who would be suitable for preventive measures. In a population based prospective study to look at the predictive capacity of cord IgE and family history of atopy 1111 one-year-old infants were followed-up. Cord IgE was measured using the EIA ultra technique (Pharmacia, Uppsala, Sweden). Atopic symptoms developed in 255 (23%) at one year, 183 (16.5%) had probable atopy (clinical disorder but negative skin prick test (SPT)) and 72 (6.5%) had definite atopy (clinical disorder with positive SPT). There was no difference in the mean cord IgE levels in infants with or without atopic manifestations. The cut-off for IgE was taken at 0.6 ku/1. The specificity of the test was 92% but the sensitivity was only 8.5%. The positive and negative predictive values were 24% and 78% respectively. Family history of atopy is far more sensitive in detecting infants at risk of atopy and little is added by knowledge of cord IgE.     

IgE levels in cord blood and at 4–5 days of age: relation to clinical symptoms of atopic disease up to 18 months of age

To evaluate the variation in serum IgE levels during the neonatal period and its relation to the development of atopy, 83 infants with a heredity of atopy were studied with regard to the concentration of IgE in cord blood (CB) and capillary blood on the fourth or fifth day of life. During the neonatal period, the average IgE level remained unchanged in the whole group but there were large individual changes. Among 22 infants with CB-IgE levels greater than or equal to 0.9 kU/l the IgE concentrations in 50% decreased below this value on days 4-5. The correlation between maternal IgE and CB-IgE concentrations (rs = 0.41; P less than 0.001) was interpreted as indicating a probable contamination with maternal blood. This view was supported by the presence of an elevated IgA level and of IgE antibodies against inhalant allergens in 16% of the cord blood samples of which 69% had an IgE level exceeding 0.9 kU/l. It therefore seems preferable to collect the blood samples on the fourth or fifth day. However, in the 74 infants available for atopic classification at 18 months of age, the positive predictive value of IgE determinations was low: on days 4-5 25-38% and in CB 42%. A high CB-IgE level may merely be an indication of the mother's atopic state.     

Immunoglobulin E assayed after pepsin digestion by an automated and highly sensitive particle counting immunoassay: application to human cord blood

We describe in this article a fully automated, universal assay for serum IgE after pepsin digestion of the sample and subsequent assay of the released Fc" epsilon fragment by particle counting immunoassay (PACIA). The sensitivity and the range of the assay were easily modulated by changing the concentration of dextran in the reaction medium. In the application to cord serum, the sensitivity reached 0.1 IU/ml in 30 min incubation time and with a throughput of 50 analyses per hour. Within-day and between-day coefficients of variation did not exceed 7.6% for IgE levels covering a wide range of the standard curve. Dependable accuracy was demonstrated by linearity tests, analytical recoveries (89% to 112%), and correlation with PRIST on 48 samples from children ages 1 to 14 yr (y = 0.97x + 5.92; r = 0.987). Minor discrepancies between the two methods were attributed to a slight serum effect in PRIST. PACIA applied to 348 cord serum samples demonstrated a statistically significant influence of sex and race on the cord IgE level. In European neonates boys had significantly (p = 0.019) higher geometrical mean cord IgE levels (n = 142; 0.46 IU/ml; range less than 0.10 to 30 IU/ml) than girls (n = 146; 0.33 IU/ml; range less than 0.10 to 8.0 IU/ml), which was attributed to a predominance of boys (chi 2 = 4.29; p less than 0.05) having more often elevated cord IgE (less than 1.20 IU/ml) than girls. Neonates of African-Asian origin had significantly (p less than 0.00005) higher cord IgE levels (n = 60; 1.05 IU/ml; range less than 0.10 to 125.0 IU/ml) than European neonates (n = 288; 0.39 IU/ml; range less than 0.10 to 30.0 IU/ml).     

Predictive value of cord blood IgE levels in 'at-risk' newborn babies and influence of type of feeding

Cord serum IgE levels were examined in 101 newborn infants ofatopic parents, and reviewed at the ages of 3, 6, 9, 12, 15, 18, 21 and 24 months, in order to determine any relation with signs and symptoms of allergic rhinitis, bronchial asthma, atopic dermatitis, urticaria and food allergy. Cord blood IgE levels were 1.06+ 1.02 U/ml in the group of infants who developed atopic disease, and 0.34 + 0.79 U./ml in the group of infants who did not develop atopy (P < 0.001). In the breast-fed group 37.5, of the infants with cord blood IgE more than 0.8 U/ml and 11.5% with IgE below 0.8 U/ml had atopic disease. In the soy-fed group 33.3% of the infants with cord blood IgE more than 0.8 U/m! and 15.8% with cord blood IgE less than 0.8 U/ml developed atopy. Ninety percent of the cow's milk-fed infants with cord blood IgE above 0.8 U/ml and 16% with cord blood IgE below 0.8 U/ml showed atopy during the follow-up period. No correlation was found between the IgE levels in maternal and respective cord blood.     

Neonatal IgE: a poor screen for atopic disease

Screening for atopic disease using neonatal serum IgE has been advocated on the basis of the predictive value of elevated levels. However, this is only one measure of validity. The test was validated fully in 92 infants with a bi-parental history of atopy using 0.7 IU/ml as the cut-off. All infants were assessed prospectively for evidence of atopic disease (eczema, recurrent wheezing or food reactions) and skin-prick test positivity in the first year. Total serum IgE was measured by ultrasensitive ELISA on 61 cord blood samples and 92 samples taken at 7 days. All cord samples were re-analysed by PRIST and the first 33 by ultrasensitive RIA giving, respectively, 82% and 94% concordance (regarding undetectable, detectable and elevated levels) with ELISA. Maternal contamination was indicated in 7% of cord samples by high serum IgA. Ninety-five per cent of cord/7-day IgE pairs showed no change or minor rises at 7 days. Forty-nine per cent of the infants had evidence of atopic disease. Only 5% had elevated 7-day IgE. The positive and negative predictive values of the 7-day test were 60% and 52%, respectively, and specificity 96% but the sensitivity was only 7%. High levels did not distinguish the infants with the most unequivocal evidence of disease, i.e. eczema with a positive skin test. In conclusion IgE at 7 days is comparable to and more reliable than cord IgE. However, neonatal IgE screening is too insensitive to have clinical application.     

Predictive value of cord blood IgE in the development of atopic disease and role of breast-feeding in its prevention

The predictive value of cord blood IgE in the development of atopic disease was evaluated in a prospective study of two groups of infants. Total serum IgE level was ≥ 0.7 U/ml in 44.3% of the infants with positive family history of atopy and in 16.0% among those with negative family history. The level of cord blood IgE correlated significantly with the subsequent development of atopic disease in both groups. Cord blood IgE higher than 0.7 U/ml was associated with a high risk of development of atopic eczema and wheezing, 52.8% and 58.8% respectively in the groups with or without family history of atopy; compared with 13.4% and 1.1% in the groups with IgE levels less than 0.7 U/ml. Among newborns fed exclusively on breast milk for a minimum of 3 months, the incidence of eczema and wheezing was significantly lower (12%) compared with findings in the formula-fed group (32%).     

Elevated cord serum IgE increases the risk of aeroallergen sensitization without increasing respiratory allergic symptoms in early childhood

BACKGROUND: Increasing prevalence of allergic disorders has focused attention on primary prevention. There is a need to improve the accuracy of early-life predictors of atopy so that the at-risk population can be accurately defined and preventive measures instituted. OBJECTIVE: The predictive capacity of elevated cord IgE, with or without family history of atopy, to allergic symptoms and skin prick test (SPT) sensitization is evaluated in a birth cohort followed up prospectively for 4 years. METHODS: A birth cohort of 1456 consecutively born children was recruited in 1989. Data were collected on family history of atopy and cord serum total IgE (cord IgE) was measured. Of these, 1218 children were seen in the clinic at 4 years to determine the development of symptoms and signs of allergic disease and 981 were skin tested to a range of common food and aeroallergens. RESULTS: Of 1218 children reviewed at age 4 years, 218 (17.8%) had symptoms of respiratory allergy and, of those skin tested (n = 981), 192 (19.6%) reacted positively. Twice as many children with elevated cord IgE (>/= 0.5 kU/L) at birth became sensitized to aeroallergens by age 4 years (34.8% vs 17.3%, P < 0. 001). Positive predictive value (PPV) of elevated cord IgE for the development of aeroallergen sensitization was better than that of family history of atopy (34.8 vs 22.6%). Combining paternal atopy with elevated cord IgE substantially increased the predictive capacity (PPV 77.8%). Cord IgE levels did not correlate with clinical asthma or rhinitis at age 4 years and PPV for allergic respiratory symptoms remained poor at all cutoffs. CONCLUSION: Cord IgE is better than family history for predicting atopy as defined by allergen sensitization and this predictive value can be further increased by combining cord IgE with paternal atopy.     

Parental history of atopic disease and concentration of cord blood IgE

Background A family history of atopy, and cord blood immunoglobulin E concentration, have been shown to be predictors of atopic disease in children. Several studies have suggested that parental atopy may be related to newborn immunoglobulin E. Objective The purpose of our analysis was to evaluate whether parental history of allergic disease was associated with cord blood immunoglobulin E concentration. Methods The study subjects were from a defined population of 777 newborns delivered between 1987 and 1989. The mothers of these children completed a questionnaire during pregnancy concerning themselves and the child's father, including parental history of physician diagnosis of allergic diseases (allergies, hay fever and asthma). Total immunoglobulin E levels were quantitated in cord blood samples with an enzyme-hnked immunoassay. Results Median cord blood immunoglobulin E concentration was higher among infants whose mothers had a history of atopic disease, particularly for those with a history of asthma (P<0.022) and allergen immunotherapy (P<0.016) vs infants whose mothers had no history of any atopic disease. Comparing all babies with a maternal history of asthma, to babies where neither parent had a history of any atopic disease, the median cord blood immunoglobulin E was significantly higher (0.36IU/mL vs 0.21 IU/mL; P<0.009). This association was found only among female infants (0.49IU/mL vs 0.20 IU/mL; P<0.001). Conclusion Maternal, but not paternal, history of atopic disease was associated with an elevated immunoglobulin E among newborns. For maternal asthma, this association was only evident in infant girls.     

Fatty acids in colostrum from mothers of children at high risk of atopy in relation to clinical and laboratory signs of allergy in the first year of life

BACKGROUND: It remains controversial whether fatty acid (FA) composition of breast milk relates to development of atopy in the infant. This study evaluates FA in colostrum from mothers of children at high risk of atopy in association with atopy at the age of 1 year. METHODS: The FA of colostrum were analyzed for 218 children (60 with low birth weight between 1500 and 2500 g, 84 with a history of maternal atopy, and 74 with an elevated cord blood immunoglobulin (Ig)E of >0.9 IU/ml). Total lipids were extracted, methylated and separated by gas-liquid chromatography. Laboratory screening for allergic sensitization and clinical examination took place within the Leipzig Allergy Risk Children's Study (LARS). RESULTS: Low birth weight was correlated with low percentage levels of 20:2n-6, 22:2n-6, and 22:3n-3 (r = 0.14, P < 0.05; r = 0.14, P < 0.05 and r = 0.20, P < 0.01, respectively) and low gestational age at birth was correlated with low 22:3n-3 (r = 0.15, P < 0.05). There was no association between FA and atopic eczema at the age of 1 year. However, high linoleic acid (LA, 18:2n-6) was linked to high specific IgE against cow's milk protein (P < 0.05), and low docosapentaenoic acid (DPA, 22:5n-3) was associated with elevated total serum IgE (P < 0.05) at the age of 1 year, respectively. CONCLUSIONS: The polyunsaturated fatty acid composition of colostrum in a high risk newborn population shows associations with atopic sensitization at the age of 1 year and may be predictive for later atopic disease.     

Significance of IgE level in amniotic fluid and cord blood for the prediction of allergy

Intrauterine sensitization has been reported in animal and clinical studies. One study suggests that the amniotic fluid (AF) IgE level might be useful in predicting infant allergy. We followed for 1 year 83 newborns on whom we had 78 samples of AF, 82 of cord serum (CS), and 83 of maternal serum (MS). All infants were delivered by C-section at term. Amniotic fluid samples were aspirated through the exposed myometrium. Sanguineous specimens were excluded. Amniotic fluid, CS, and MS were tested for total IgE level and IgE RAST to three foods: cow's milk, egg white, and peanut. Data on family medical history, feeding history, and allergy symptoms were collected for 12 months. By 1 year 23% had probable allergy: recurrent wheezing = 8, food related G.I. symptoms = 7, and atopic dermatitis = 4. Allergy in formula-fed infants occurred more often than in those breast-fed for greater than 6 months. IgE in AF was greater than or equal to 0.5 IU/mL in 21/78 (27%); range = 0.5 to 5.9 and geometric mean = 0.76. No correlation was noted between AF total IgE and the appearance of allergy. RAST was equivocally positive in 1.2% AF. Cord serum total IgE was greater than or equal to 0.5 IU/mL in 6/82 (7%); range = 0.5 to 2.6 and geometric mean = 0.72. Allergy appeared in 67% of infants with CS total IgE greater than or equal to 0.5 IU/mL. RAST was negative in all CS samples. In this limited series, AF IgE did not seem to have predictive value of allergy in infancy.     

Atopy, intestinal helminth infection and total serum IgE in rural and urban adult Gambian communities

BACKGROUND: The rarity of atopy in traditional societies has been attributed to high parasite-driven blocking IgE concentrations. Information is lacking on the relationship between atopy, IgE and intestinal helminth infection in African populations. OBJECTIVE: To determine the prevalence of atopy and intestinal helminth infection and to relate these to wheeze history and serum total IgE in a community sample of adults from an urban (Banjul) and a rural (Farafenni) area of the Gambia. METHODS: Six hundred and ninety-three adults were interviewed about respiratory symptoms using a modified version of the IUTLD questionnaire, and had skin prick testing using four allergens. Stools were examined after formol-ether concentration. Total serum IgE concentration was measured in a subset of participants. RESULTS: The prevalence of atopy (mean weal diameter > or = 3 mm) in the urban and rural area was 35.3% and 22.5% (P = 0.05); D. pteronyssinus and Mold mix being the common sensitizing allergens. Prevalence of wheeze in the previous 12 months was 4.4% and 3.5% for the urban and rural areas, respectively. Wheezing was not significantly associated with atopy. Seventeen per cent of urban and 8.2% of rural subjects had helminths detected in stools. There was an inverse association between atopy and intestinal helminth infection; 7% of atopic subjects had helminths, compared to 13% of non-atopic subjects (unadjusted odds ratio 0.51, 95%CI 0.24-1.1, P = 0.09; adjusted odds ratio 0.37, 95%CI 0.15-0.92, P = 0.03). Non-atopics had total serum IgE concentrations about 2.5 times the upper limit of the reference range in non-atopic Western populations. Geometric mean total serum IgE concentration was significantly higher among atopic subjects (570 IU/mL, IQR 91-833) than non-atopic subjects (259 IU/mL, IQR 274-1303) (P < 0.001). IgE concentration was not associated with the presence of helminth infection. CONCLUSION: Further studies are needed to clarify why asthma is still relatively uncommon in spite of the prevalence of atopy in Gambian adults. Our data are also compatible with the idea that atopy might protect against helminth infection.     

Serum levels of IgG subclasses in relation to IgE and atopic disease in early infancy

The levels of IgG1, IgG2, IgG3, and IgG4 were analysed by ELISA in cord serum and in serum samples collected at 6 and 18 months of age from infants whose mothers were atopic. None of the four IgG subclasses was significantly influenced on any sampling occasion by infant atopy, gender, month of birth, maternal IgE or maternal diet during pregnancy and early lactation. However, at 18 months of age, significantly higher levels of IgG1 (P less than 0.05) and of IgG4 (P less than 0.01) were found in infants with an elevated IgE (greater than or equal to 8.0 kU/l) than in those with a lower level. A weak positive correlation (rs = 0.26; P = 0.05) between IgE and IgG4 was also observed. Despite the fact that the serum levels of IgG4 at 18 months were significantly higher (P less than 0.01) among infants with positive IgE-RAST (greater than or equal to 0.15 PRU/ml) to ovomucoid or beta-lactoglobulin, our data suggest that the the concentration of IgG4 relates more to the level of IgE than to the clinical symptoms of atopy. Determination of IgG subclasses seems to be of limited value for prediciting atopy during early infancy.     

Comparison of cord blood immunoglobulin E concentrations and maternal allergy for the prediction of atopic diseases in infancy

Total serum IgE levels were determined in 136 newborns and their mothers and in 54 of their fathers, using the paper radioimmunosorbent test (PRIST) technique. IgE specific antibodies for house dust (Dermatophagoides pteronyssinus), orchard grass, timothy grass, and cow's milk were measured with the radioallergosorbent test (RAST). One hundred thirty-three RAST assays were negative in newborns, and in three cases RAST for cow's milk was positive. Cord blood IgE ranged from 0 to 5.5 IU/ml (mean 0.32 ± 0.54 IU/ml); levels were significantly (p < 0.05) higher when maternal IgE was over 100 IU/ml and when mothers had received progesterone therapy during the pregnancy. Salbutamol administration or tobacco smoking during pregnancy did not influence newborn IgE. A clinical follow-up study was conducted in 83 infants for 9 mo. Nine infants developed definite atopic disease, and possible allergic diseases were noted in eight other infants. The IgE level at birth appeared to be more predictive for the development of allergy in infancy than the family history.     

Predictability of early atopy by cord blood-IgE and parental history

Background Atopic family history and cord blood IgE have been used as predictors of atopic disease in newborns for about 20 years, but at least for cord blood IgE the sensitivity has been shown to be very low. The objective of this paper was to evaluate whether parental history and cord blood-IgE were more accurate predictors for the appropriate atopic phenotypes in the infants rather than for any atopy. Methods A total of 1314 newborn infants was recruited in six German obstetric departments in 1990 and followed-up for 2 years. Four hundred and ninty-ninc (38%) were at high risk for atopy with at least two first degree atopic family members and/or elevated cord-blood IgE concentrations. Results The cumulative incidence of atopic dermatitis over the first 2 years of life (AD24) amounted to 20. 1%, and there was a significant association with AD history of the mother (OR 2.5, 95%-Cl 1.46–4.26) and of the father (OR 3.53, 95%cC1 1.90–6.54). The cumulative incidence of recurrent wheezing in the first 2 years of life (RW24) amounted to 16.1%, and was positively associated with asthma history (OR 2.11, 95%CI 1.33–3.60) and sensitization history (OR 1.64, 95%C1 1.34–2.36) of the mother, but with neither for the father. RW24 was less prevalent in girls than in boys (OR 0.64. 95%Cl 0.47–0.89). Thirty-one per cent of infants were sensitized (CAP test value > 0.35 kU/L) against at least one of nine food or inhalative allergens (S24) and this was signilicantly associatcd with cord blood-IgE value (OR 2.43, 95%C1 1.69–3.49). and sensitization history of the mother (OR 1.64, 95%CI 1.18–2.41). Using multiple logistic regression analysis, the prediction of AD24 by AD of parents, of RW24 by asthma of parents, and of sensitization by cord blood IgE was of low accuracy. Conclusion The predictive capacity of parental history and cord blood IgE is not high enough to recommend them as screening instruments for primary prevention. The majority of atopic manifestations and of sensitization occur in infants with no demonstrable risk at birth.     

Relationship between IgE and specific aeroallergen sensitivity in Alaskan native children.

BACKGROUND: The relationship between atopic disease and serum IgE levels varies among populations and geographic regions. The close association of atopy with IgE may not occur in subarctic populations as it does in developed countries in temperate climates. OBJECTIVE: To evaluate the relationship between total and specific IgE concentrations and clinical atopy in 5- to 8-year-old Alaskan native children. METHODS: Medical record reviews, interviews, physical examinations, serum IgE measurements, and radioallergosorbent testing (RAST) were performed. RESULTS: The IgE geometric mean was 122.1 IU/mL. Fifty-eight percent of patients had IgE levels greater than 70 IU/mL, and 17% had levels greater than 1,000 IU/mL; 14% had RAST values greater than 0.35 kU/L. Both IgE levels greater than 70 IU/mL and greater than 1,000 IU/mL were associated with RAST values greater than 0.35 IU/L (P = .004) and early wheezing (P = .005) but not with current wheezing, asthma, eczema, or a history of allergies. A RAST value greater than 3.51 kU/L was associated with eczema (P = .04) but not with allergies or wheezing. Children with current wheezing were more likely to have allergies (P = .03) but not eczema, an IgE level greater than 70 IU/mL, or a positive RAST value. Children hospitalized with respiratory syncytial virus (RSV) were not more likely than controls to have current wheezing. CONCLUSIONS: Elevated serum IgE concentrations, including levels greater than 1,000 IU/mL, are common among Alaskan native children; positive RAST reactions to aeroallergens are not. The IgE levels do not relate to wheezing, eczema, a history of allergies, or past hospitalization for RSV infection but likely reflect infections other than RSV and environmental factors in subarctic indigenous populations.     

Interaction of maternal atopy, CTLA-4 gene polymorphism and gender on antenatal immunoglobulin E production

BACKGROUND: Genetic heritability and maternal atopy have been correlated to antenatal IgE production, but very few studies have studied gene-maternal atopy interaction on antenatal IgE production. This study investigated the interaction of CTLA-4 polymorphism with prenatal factors on the elevation of cord blood IgE (CBIgE). METHODS: Pregnant women were antenatally recruited for collection of prenatal environmental factors by a questionnaire. Umbilical cord blood samples were collected for CBIgE detection by fluorescence-linked enzyme assay and CTLA-4 polymorphism measurement by restriction fragment length polymorphism. RESULTS: A total of 1104 pregnant women initially participated in this cohort study, and 898 of them completed cord blood collection. 21.4% of the newborns had elevation of CBIgE (>or=0.5 kU/L). The CTLA-4+49A allele (P=0.021), maternal atopy (P<0.001) and gender (P=0.034), but not the CTLA-4+49G allele, -318C allele, -318T allele, parental smoking or paternal atopy, were significantly correlated with the CBIgE elevation in multivariate analysis. A dichotomous analysis of gene-maternal atopy interactions identified maternal atopy and CTLA-4+49A allele had an additive effect on the CBIgE elevation, especially prominent in male newborns; and in the absence of maternal atopy, CTLA-4+49GG genotype had a protective effect on CBIgE elevation in female newborns. CONCLUSIONS: Maternal but not paternal atopy has significant impacts on CBIgE elevation depending on gender and CTLA-4+49A/G polymorphism of newborns. Control of maternal atopy and modulation of CTLA-4 expression in the prenatal stage may be a target for the early prevention of perinatal allergy sensitization.