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Biomedical subjects

H Oman

Publications and source records attributed to H Oman.

33 records · Page 2Linked to original sources
PubMed1996

Development of atopic disease during childhood and its prediction by Phadiatop Paediatric.

BACKGROUND: Evaluating in vivo and/or in vitro tests for 'early' prediction of childhood allergy is of interest in paediatric allergology. OBJECTIVE: To determine whether the measurement of Phadiatop Paediatric (PP) during early childhood could be used to predict the development of atopic disease during the first 5 years of life among infants with a family history of atopic disease. METHODS: Phadiatop Paediatric was evaluated in 134 infants. The analysis was performed at 6 months, at 18 months and at 5 years of age and the numbers of available serum samples were 61, 85 and 134, respectively. The potential capacity of the test to predict the development of atopic disease was studied by relating the result of the test, a positive or a negative score, to the accumulated incidence of atopic diseases from birth to 18 months of age and from birth to 5 years of age. RESULTS: Three of four children with a positive PP at 6 months of age developed clinical signs/symptoms of atopic disease before 18 months and all four before 5 years of age. The predictive value of a positive test at 18 months for symptoms before 5 years of age was 80% (12/15). If the diagnostic criterion, instead of clinical signs/symptoms of atopic disease, was at least one positive skin-prick test to major food or inhalant allergens, the predictive value of a positive PP-test at 18 months decreased to 53% (8/15). CONCLUSION: Although the presence of circulating IgE antibodies, as detected by Phadiatop Paediatric, can predict the development of atopic diseases during childhood, the usefulness of the test is limited by its low sensitivity (22-47%).

Allergens↗
PubMed1995

Screening of atopic allergy in 5-year-old children--a comparison of the diagnostic properties of Phadiatop Paediatric and Phadiatop.

The ability of Phadiatop Paediatric (PP), Phadiatop (P), mixed-food RAST (MF), and the combination of P and MF to identify children with atopic allergy was evaluated among 193 children who had a family history of atopic disease, and who had an average age of 5 years. If atopy is defined as the presence of at least one positive skin prick test (> or = 2+) to common food and/or inhalant allergens, P had a sensitivity of 86%, a specificity of 94%, and an efficacy of 92%. These figures were somewhat better than the results with PP. However, when P was combined with MF, the sensitivity increased to 89%, but at the expense of lowered specificity (83%) and efficacy (84%). If the tests were related only to clinical signs/symptoms of atopic disease, the sensitivity and efficacy were, at maximum, 63% and 81%, respectively. There was a discrepancy between the results of P and PP in 9% of the children. One explanation of this discrepancy may be that PP seems to be incapable of detecting children with respiratory allergies induced by pollens from birch and related trees. The results indicate that in 5-6-year-old children P should be preferred to PP and to the combination of P and MF for atopy screening, at least in places where birch pollen is a common allergen.

Child, Preschool↗
PubMed1995

Neonatal IgA and IgE levels among infants with paternal heredity for atopic disease.

Serum IgA and IgE levels were studied in the postnatal period in 21 infants having a paternal heredity of atopic disease. Three different sampling techniques were used, aspirated cord blood (CB), gravity-collected cord blood, and capillary collected blood at 4-5 days of age. Significant differences among the three sampling techniques were recorded for IgA (P < 0.01), but not for IgE. The IgA levels decreased from birth to 4-5 days of age in 90% (19/21 of infants (P < 0.01). The corresponding decrease in IgE levels was 20%. This postnatal difference in the frequency of decreasing/increasing IgA and IgE levels was significant (P < 0.05). An analysis of CB IgA to detect maternal contamination of CB was found to be of questionable value, since only 50% (2/4) of the cases with an elevated CB-IgA level could be considered contaminated. The results of this study further emphasize that aspiration of CB and capillary collection of blood at 4-5 days of age are the best sampling techniques to avoid contamination. The general finding that paternal heredity had no significant influence on infant IgE contrasts with the strong influence of maternal heredity. Further studies will show whether the explanation lies in genetic or transplacental factors, or in both kinds of factors.

Fetal Blood↗
PubMed1995

Comparison of polysucrose 15000, 51Cr-labelled ethylenediaminetetraacetic acid, and 14C-mannitol as markers of intestinal permeability in man.

BACKGROUND: We recently reported increased intestinal permeability to polysucrose (PS) 15000 in patients with Crohn's disease and in patients treated with non-steroidal anti-inflammatory drugs (NSAIDs). We have now compared this new macromolecular marker (14,700 D) with the conventional markers, 51Cr-labelled ethylenediaminetetraacetic acid (EDTA) (342 D) and 14C-mannitol (182 D), in healthy humans. METHODS: Twenty healthy volunteers on four occasions ingested a solution containing PS 15000, 51Cr-EDTA, and 14C-mannitol, the test solution being, respectively, isoosmolar, hyperosmolar, isoosmolar followed by a standard meal, and isoosmolar after 1 week of NSAID treatment. Fractional urinary excretion of the substances was measured over 0-4 h, 4-8 h, and 8-12 h. RESULTS: The excretion of PS 15000 was, like that of 51Cr-EDTA but unlike that of 14C-mannitol, increased by NSAID pretreatment, little affected by hyperosmolar test solution, little correlated to urinary volume, and skew with regard to frequency distribution. Despite being nominally about 40 times lower, the excretion of PS 15000 was highly correlated to that of 51Cr-EDTA but not to that of 14C-mannitol. A standard meal reduced the test variability for all three probes. CONCLUSIONS: PS 15000 may be an alternative to 51Cr-EDTA as a small-intestinal permeability marker. Inclusion of a standard meal reduces test variability.

Adult↗
PubMed1992

Neonatal IgE levels and three different blood sampling techniques.

Comparison was made of IgE and IgA levels in aspirated and gravity-collected cord blood (CB) from the umbilical vein and in capillary blood samples collected on the 4-5th day of life among 21 infants with atopic heredity. The IgA levels, but not the IgE levels, were significantly (p < 0.001) lower at days 4-5 of life than at delivery. Further, there were significantly (p < 0.05) more infants with decreasing IgA levels (20/21; 95%) than IgE levels (9/15; 60% of those with detectable IgE, i.e., > or = 0.125 kU/l). These observations, together with the highly significant correlation observed between IgE in aspirated CB samples and at 4-5 days of age, suggest active IgE synthesis during the prenatal and postnatal periods. Contamination of CB with maternal blood, defined as an increased CBIgA level (> or = 14.1 micrograms/ml), was found in 3 (14%) CB samples, all of which were gravity-collected. Of 4 CB samples (gravity-collected) with elevated IgE (i.e., > or = 0.9 kU/l), 2 had suspected maternal contamination. Therefore, aspiration of CB or capillary collection at 4-5 days of age should be preferred for allergy prediction. If gravity collection is used, contamination should be investigated by determining IgA in all CB samples with IgE concentrations exceeding the cut-off point.

Adult↗
PubMed1992

Chemical and physiological properties of polysucrose, a new marker of intestinal permeability to macromolecules.

To measure intestinal absorption of macromolecules we have developed a new technique employing synthetic polysucrose polymers as probe molecules. Polysucrose (PS) is water-soluble, nontoxic, resistant to intestinal enzymes, spherical and can be produced with a molecular weight distribution that relates to the size of many normal food proteins. Normally, a very small fraction of large molecules passes the exclusion barrier of the healthy intestine. Thus, quantification of resorbed macromolecules requires assays of high sensitivity. For detection of PS in various biological fluids, micro-ELISAs have been established. PS with a mean molecular weight of 14,700 daltons (PS 15,000) is rapidly excreted into the urine. Twenty-one healthy volunteers who orally ingested 1 g of this preparation showed a 12-hour urine excretion of 0.018% (interquartile range 0.014-0.022).

Adult↗
PubMed1991

Effects of maternal diet during late pregnancy and lactation on the development of IgE and egg- and milk-specific IgE and IgG antibodies in infants.

The IgE levels and food-allergen-specific IgE- and IgG-antibodies (Ab) to ovalbumin (OA), ovomucoid (OVO) and beta-lactoglobulin (BLG) were determined up to 18 months of age in 163 infants born to women who were atopic. A high (HIGH group) or a low (REDUCED group) intake of hen's egg and cow's milk by the mother during the third trimester gave no significant differences in the concentrations of IgE or in IgE-Ab (OVO, BLG) and IgG-Ab (OA, OVO, BLG). Similarly, a prolongation of the abstention diet to the early lactation period did not influence the immune response. The IgG-Ab levels to all three food allergens decreased significantly (P less than 0.001) in both study groups between birth and 2 months of age, but then increased significantly (P less than 0.001) between 6 and 18 months of age. The presence in serum of IgE-Ab to OVO (greater than or equal to 0.15 PRU/ml) was associated with significantly higher IgG-Ab levels to OVO at 6 months (P less than 0.001) and at 18 months (P less than 0.05). Infants with positive skin-prick tests (SPT) to OA and OVO showed higher IgG-Ab levels at 6 and 18 months of age than did infants with negative SPT reactions to the two egg allergens. This indicates a relation between the IgE- and IgG-Ab response and it also suggests that some individuals are 'high responders' to both types of immunoglobulin isotypes while others are 'low responders'.

Allergens↗
PubMed1990

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.

Aging↗
PubMed1990

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.

Adolescent↗
PubMed1989

Effects of maternal diet during late pregnancy and lactation on the development of atopic diseases in infants up to 18 months of age--in-vivo results.

One hundred and sixty-two women with respiratory allergy to animal danders and/or pollens were randomly allocated to a diet consisting of either a very low ingestion of hens' egg and cows' milk or a daily ingestion of one hens' egg and about 11 of cows' milk during the last 3 months of pregnancy. One hundred and sixty-three infants were followed prospectively up to 18 months of age when the cumulated incidence of atopic disease in each child was evaluated blindly. No significant differences in the distribution of atopic disease were found among the infants in relation to the maternal diet during late pregnancy. The numbers of skin-prick tests positive to ovalbumin, ovomucoid, beta-lactoglobulin and cows' milk were likewise not influenced by differences in the maternal diet during late pregnancy. Genetic factors rather than maternal diet during the perinatal period probably have a greater effect on the incidence of atopic diseases during early infancy.

Adult↗
PubMed1988

Immune response of the atopic woman and foetus: effects of high- and low-dose food allergen intake during late pregnancy.

The influence of the mother's consumption of cows' milk and hens' egg on the immune response (IgE, IgG) in the mother and foetus was studied in 165 pregnant women with atopical respiratory disease with an allergy to pollen and/or animal dander. The women were randomly allocated to four diets ranging from a diet free from hens' egg and cows' milk to a diet containing intake of one egg and one litre of milk daily during the third trimester. No significant differences in cord blood IgE levels were noted in spite of differences in maternal diet, and no specific IgE antibodies to ovalbumin, ovomucoid and betalatoglobulin were found in the cord blood. The mother's IgG antibody concentrations to ovalbumin, ovomucoid and betalactoglobulin were influenced by her diet, but cord blood IgG antibody levels to the selected food allergens were unaffected. The data presented on the IgE and IgG antibody levels to ovalbumin, ovomucoid and betalactoglobulin in cord blood suggest that changes in maternal diet during the last trimester of pregnancy in order to prevent atopic sensitization in utero are less likely to affect the foetus than previously supposed.

Adult↗
PubMed1987

Maternal abstention from cow milk and egg in allergy risk pregnancies. Effect on antibody production in the mother and the newborn.

To study the possibility of intrauterine sensitization, 212 women were enrolled on a voluntary basis into a prospective, randomized study, comparing the effects of an elimination diet and normal food during late pregnancy. The diet group took no cow milk and no egg from week 28 to delivery, and extra calcium and casein hydrolysate (Nutramigen) supplement was given to fill the nutritional needs of mother and child. The control group took normal food, including approximately 1/2 liter of milk/day and 3-5 eggs/week. All families had a history of allergy in mother, father, or sibling. Maternal weight gain during pregnancy was significantly lower in the diet group. Birth weights showed no significant difference between the two main groups, but smokers in the elimination diet group had significantly smaller babies. IgE antibodies to cow milk and egg were significantly higher in atopic than in non-atopic women before the trial. The diet caused a significant fall in IgG-antibodies to cow milk and egg in both atopic and non-atopic subjects. Cord blood IgE determination revealed no significant difference between the groups. No IgE antibodies to cow milk or egg were detected in any of the cord sera. The participating babies are being followed up until 18 months of age.

Animals↗