Early introduction of peanut reduces peanut allergy across risk groups in pooled and causal inference analyses

BACKGROUND

The Learning Early About Peanut allergy (LEAP) study has shown the effectiveness of early peanut introduction in prevention of peanut allergy (PA). In the Enquiring About Tolerance (EAT) study, a statistically significant reduction in PA was present only in per-protocol (PP) analyses, which can be subject to bias.

OBJECTIVE

The aim of this study was to combine individual-level data from the LEAP and EAT trials and provide robust evidence on the bias-corrected, causal effect of early peanut introduction.

METHOD

As part of the European Union-funded iFAAM project, this pooled analysis of individual pediatric patient data combines and compares effectiveness and efficacy estimates of oral tolerance induction among different risk strata and analysis methods.

RESULTS

An intention-to-treat (ITT) analysis of pooled data showed a 75% reduction in PA (p < .0001) among children randomized to consume peanut from early infancy. A protective effect was present across all eczema severity groups, irrespective of enrollment sensitization to peanut, and across different ethnicities. Earlier age of introduction was associated with improved effectiveness of the intervention. In the pooled PP analysis, peanut consumption reduced the risk of PA by 98% (p < .0001). A causal inference analysis confirmed the strong PP effect (89% average treatment effect relative risk reduction p < .0001). A multivariable causal inference analysis approach estimated a large (100%) reduction in PA in children without eczema (p = .004).

CONCLUSION

We demonstrate a significant reduction in PA with early peanut introduction in a large group of pooled, randomized participants. This significant reduction was demonstrated across all risk subgroups, including children with no eczema. Furthermore, our results point to increased efficacy of the intervention with earlier age of introduction.

Primary and pollen-associated hazelnut allergy in school-aged children in Germany: A birth cohort study

BACKGROUND

Primary hazelnut allergy is a common cause of anaphylaxis in children, as compared to birch-pollen associated hazelnut allergy. Population-based data on hazelnut and concomitant birch-pollen allergy in children are lacking. We aimed to investigate the prevalence of primary and pollen-associated hazelnut allergy and sensitization profiles in school-aged children in Berlin, Germany.

METHODS

1570 newborn children were recruited in Berlin in 2005-2009. The school-age follow-up (2014-2017) was based on a standardized web-based parental questionnaire and clinical evaluation by a physician including skin prick tests, allergen specific immunoglobulin E serum tests and placebo-controlled double-blind oral food challenges, if indicated.

RESULTS

1004 children (63.9% response) participated in the school-age follow-up assessment (52.1% male). For 1.9% (n = 19, 95%-confidence interval 1.1%-2.9%) of children their parents reported hazelnut-allergic symptoms, for half of these to roasted hazelnut indicating primary hazelnut allergy. Symptoms of birch-pollen allergy were reported for 11.6% (n = 116 95%-CI 9.7%-13.7%) of the children. Both birch-pollen allergy and hazelnut allergy associated symptoms affected 0.6% (n = 6, 95%-CI 0.2%-1.3%) of children. Assessment of allergic sensitization was performed in 261 participants and showed that almost 20% of these children were sensitized to hazelnut, being the most frequent of all assessed food allergens, or birch-pollen, the majority to both.

CONCLUSIONS

Based on parental reports hazelnut-allergic symptoms were far less common than sensitization to hazelnut. This needs to be considered by physicians to avoid unnecessary changes in diet due to sensitization profiles only, especially when there is a co-sensitization to hazelnut and birch-pollen.

Prevalence and early-life risk factors of school-age allergic multimorbidity: The EuroPrevall-iFAAM birth cohort

Background

Coexistence of childhood asthma, eczema and allergic rhinitis is higher than can be expected by chance, suggesting a common mechanism. Data on allergic multimorbidity from a pan‐European, population‐based birth cohort study have been lacking. This study compares the prevalence and early‐life risk factors of these diseases in European primary school children.

Methods

In the prospective multicentre observational EuroPrevall‐iFAAM birth cohort study, we used standardized questionnaires on sociodemographics, medical history, parental allergies and lifestyle, and environmental exposures at birth, 12 and 24 months. At primary school age, parents answered ISAAC‐based questions on current asthma, rhinitis and eczema. Allergic multimorbidity was defined as the coexistence of at least two of these.

Results

From 10,563 children recruited at birth in 8 study centres, we included data from 5,572 children (mean age 8.2 years; 51.8% boys). Prevalence estimates were as follows: asthma, 8.1%; allergic rhinitis, 13.3%; and eczema, 12.0%. Allergic multimorbidity was seen in 7.0% of the whole cohort, ranging from 1.2% (Athens, Greece) to 10.9% (Madrid, Spain). Risk factors for allergic multimorbidity, identified with AICc, included family‐allergy‐score, odds ratio (OR) 1.50 (95% CI 1.32–1.70) per standard deviation; early‐life allergy symptoms, OR 2.72 (2.34–3.16) for each symptom; and caesarean birth, OR 1.35 (1.04–1.76). Female gender, OR 0.72 (0.58–0.90); older siblings, OR 0.79 (0.63–0.99); and day care, OR 0.81 (0.63–1.06) were protective factors.

Conclusion

Allergic multimorbidity should be regarded as an important chronic childhood disease in Europe. Some of the associated early‐life factors are modifiable and may be considered for prevention strategies.

Frequency of food allergy in school-aged children in eight European countries-The EuroPrevall-iFAAM birth cohort

BACKGROUND

The prevalence of food allergy (FA) among European school children is poorly defined. Estimates have commonly been based on parent-reported symptoms. We aimed to estimate the frequency of FA and sensitization against food allergens in primary school children in eight European countries.

METHODS

A follow-up assessment at age 6-10 years of a multicentre European birth cohort based was undertaken using an online parental questionnaire, clinical visits including structured interviews and skin prick tests (SPT). Children with suspected FA were scheduled for double-blind, placebo-controlled oral food challenges (DBPCFC).

RESULTS

A total of 6105 children participated in this school-age follow-up (57.8% of 10 563 recruited at birth). For 982 of 6069 children (16.2%), parents reported adverse reactions after food consumption in the online questionnaire. Of 2288 children with parental face-to-face interviews and/or skin prick testing, 238 (10.4%) were eligible for a DBPCFC. Sixty-three foods were challenge-tested in 46 children. Twenty food challenges were positive in 17 children, including seven to hazelnut and three to peanut. Another seventy-one children were estimated to suffer FA among those who were eligible but refused DBPCFC. This yielded prevalence estimates for FA in school age between 1.4% (88 related to all 6105 participants of this follow-up) and 3.8% (88 related to 2289 with completed eligibility assessment).

INTERPRETATION

In primary school children in eight European countries, the prevalence of FA was lower than expected even though parents of this cohort have become especially aware of allergic reactions to food. There was moderate variation between centres hampering valid regional comparisons.

A new framework for the documentation and interpretation of oral food challenges in population-based and clinical research

BACKGROUND

The conduct of oral food challenges as the preferred diagnostic standard for food allergy (FA) was harmonized over the last years. However, documentation and interpretation of challenge results, particularly in research settings, are not sufficiently standardized to allow valid comparisons between studies. Our aim was to develop a diagnostic toolbox to capture and report clinical observations in double-blind placebo-controlled food challenges (DBPCFC).

METHODS

A group of experienced allergists, paediatricians, dieticians, epidemiologists and data managers developed generic case report forms and standard operating procedures for DBPCFCs and piloted them in three clinical centres. The follow-up of the EuroPrevall/iFAAM birth cohort and other iFAAM work packages applied these methods.

RECOMMENDATIONS

A set of newly developed questionnaire or interview items capture the history of FA. Together with sensitization status, this forms the basis for the decision to perform a DBPCFC, following a standardized decision algorithm. A generic form including details about severity and timing captures signs and symptoms observed during or after the procedures. In contrast to the commonly used dichotomous outcome FA vs no FA, the allergy status is interpreted in multiple categories to reflect the complexity of clinical decision-making.

CONCLUSION

The proposed toolbox sets a standard for improved documentation and harmonized interpretation of DBPCFCs. By a detailed documentation and common terminology for communicating outcomes, these tools hope to reduce the influence of subjective judgment of supervising physicians. All forms are publicly available for further evolution and free use in clinical and research settings.

Randomized placebo-controlled trial of hen's egg consumption for primary prevention in infants

BACKGROUND

Hen's egg is the most common cause of food allergy in early childhood.

OBJECTIVE

We investigated the efficacy and safety of early hen's egg introduction at age 4 to 6 months to prevent hen's egg allergy in the general population.

METHODS

This randomized, placebo-controlled trial included 4- to 6-month-old infants who were not sensitized against hen's egg, as determined based on specific serum antibodies (IgE). These infants were randomized to receive either verum (egg white powder) or placebo (rice powder) added to the first weaning food 3 times a week under a concurrent egg-free diet from age 4 to 6 until 12 months. The primary outcome was sensitization to hen's egg (increased specific serum IgE levels) by age 12 months. Hen's egg allergy (secondary outcome) was confirmed by double-blind, placebo-controlled food challenges.

RESULTS

Among 406 screened infants, 23 (5.7%) had hen's egg-specific IgE before randomization. Seventeen of 23 underwent subsequent double-blind, placebo-controlled food challenges, and 16 were confirmed as allergic, including 11 with anaphylactic reactions. Of the 383 nonsensitized infants (56.7% male), 184 were randomized to verum and 199 to placebo. At 12 months of age, 5.6% of the children in the verum group were hen's egg sensitized versus 2.6% in the placebo group (primary outcome; relative risk, 2.20; 95% CI, 0.68-7.14; P = .24), and 2.1% were confirmed to have hen's egg allergy versus 0.6% in the placebo group (relative risk, 3.30; 95% CI, 0.35-31.32; P = .35).

CONCLUSION

We found no evidence that consumption of hen's egg starting at 4 to 6 months of age prevents hen's egg sensitization or allergy. In contrast, it might result in frequent allergic reactions in the community considering that many 4- to 6-month-old infants were already allergic to hen's egg.

Chemokine levels in serum of children with atopic dermatitis with regard to severity and sensitization status

BACKGROUND

Many infants with atopic dermatitis (AD) are sensitized against food or airborne allergens. The severity of AD, using the SCORAD, seems to correlate with elevated serum levels of TARC/CCL17. Other chemokines, such as CCL20 or CCL25, have been described in the context of allergic inflammation. The aim of this study was to analyze whether chemokine serum levels differ within a cohort of infants suffering from varying severities of AD with or without allergic sensitization.

METHODS

Chemokine serum levels (CCL8, CCL17, CCL20, CCL25) as well as food and airborne allergen-specific IgE were analyzed in infants with AD.

RESULTS

About 60.9% (78/128) infants with AD (median age 8.8 months, 49 (38%) girls and 79 (62%) boys) showed a positive screening test to common food allergens and 26.6% to common airborne allergens. There was a strong correlation between serum levels of CCL17 and SCORAD in food-sensitized infants (r(s) = 0.646, p = <1e-04) and airborne-sensitized infants (r(s) = 0.587, p = 0.00065) in contrast to non-sensitized ones. Moreover, food-sensitized infants showed significantly higher levels of CCL25 compared to non-food-sensitized ones (p = 0.007).

CONCLUSION

The strong correlation between TARC/CCL17 and SCORAD in infants with specific sensitizations may be accounted for by the impaired skin barrier. As TARC/CCL17 has been found mainly in the (inflamed) skin but not in the gut, the detection of significantly higher levels of CCL25, ligand of CCR9, localized primarily in the gastrointestinal tract, suggests its impact on food allergen-induced inflammation processes in food-sensitized infants.

Detection of relevant amounts of cow's milk protein in non-pre-packed bakery products sold as cow's milk-free

BACKGROUND

Currently, there is no mandatory labelling of allergens for non-pre-packed foods in the EU. Therefore, consumers with food allergy rely on voluntary information provided by the staff. The aim of this study was to characterize allergic reactions to non-pre-packed foods and to investigate whether staff in bakery shops were able to give advice regarding a safe product choice.

METHODS

Questionnaires were sent to 200 parents of children with a food allergy. Staff of 50 bakery shops were interviewed regarding selling non-pre-packed foods to food-allergic customers. Bakery products being recommended as 'cow's milk-free' were bought, and cow's milk protein levels were measured using ELISA.

RESULTS

A total of 104 of 200 questionnaires were returned. 25% of the children experienced an allergic reaction due to a non-pre-packed food from bakery shops and 20% from ice cream parlours. Sixty percent of the bakery staff reported serving food-allergic customers at least once a month, 24% once a week. Eighty four percent of the staff felt able to advise food-allergic consumers regarding a safe product choice. Seventy three 'cow's milk-free' products were sold in 44 bakery shops. Cow's milk could be detected in 43% of the bakery products, 21% contained >3 mg cow's milk protein per serving.

CONCLUSION

Staff in bakery shops felt confident about advising customers with food allergy. However, cow's milk was detectable in almost half of bakery products being sold as 'cow's milk-free'. Every fifth product contained quantities of cow's milk exceeding an amount where approximately 10% of cow's milk-allergic children will show clinical relevant symptoms.

[Quality rating of follow-up examinations conducted on breast cancer patients]

For breast centre certification, follow-up care data have to be presented, although the further treatment is carried out outside of the hospital. An analysis of 2062 patients with their first operation (breast cancer and carcinoma in situ) occurring between 1.1.1984 and 31.12.1998 has been conducted. The tracking of follow-up results ended on 1.7.2007. The survival of breast cancer patients appears to be superior in the pure clinical register than with cross-linking with additional registers (Epidemiological Cancer Register and registration of address office). The outcome of this is that the completed feedback of the cases of death (Cancer Register) and of living patients (registration of address office) increases the qualitative statement. The compliance with the data security laws may be ensured by pseudo-anonymisation.

Co-expression and prognostic value of gross cystic disease fluid protein 15 and mammaglobin in primary breast cancer

Gross cystic disease fluid protein (GCDFP-15) and mammaglobin are both widely used and accepted markers for epithelia of breast origin. We aimed to evaluate their relation of expression on parallel whole tissue sections in primary breast cancer by immunohistochemistry and also to correlate it with clinico-pathological parameters including patient survival. Primary breast carcinomas from 165 patients with a mean clinical follow-up of 73 months were immunostained using commercially available antibodies against GCDFP-15 and mammaglobin. An immunoreactive score (IRS) was calculated based on the cytoplasmic staining intensity and the number of cells stained. Cytoplasmic expression of GCDFP-15 and mammaglobin was observed in 73.3% and 72.1% of invasive breast carcinomas respectively. 91.8% of breast cancer cases expressed at least one of both markers. Both markers strongly correlated with each other and were significantly associated with lower tumour grading. Additionally, GCDFP-15 negativity was significantly associated with shortened disease-free survival times in univariate and multivariate analyses. We demonstrated the strong correlation of GCDFP-15 and mammaglobin with each other and showed that only very few primary breast cancers are completely negative for both markers. The significantly longer disease free survival times for patients with GCDFP-15 positive tumours clearly warrants further study.

ALCAM/CD166 is overexpressed in colorectal carcinoma and correlates with shortened patient survival

BACKGROUND

Activated leucocyte cell adhesion molecule (ALCAM) has been implicated in tumorigenesis and tumour progression of malignant melanoma and prostate cancer.

AIMS

To clarify the expression patterns of ALCAM in colon cancer and to correlate these with clinicopathological parameters, including patient survival.

METHODS

One hundred and eleven colorectal carcinomas were immunostained for ALCAM (clone MOG/07) using a standard detection system. Cytoplasmic and membranous immunoreactivity were scored semiquantitatively. Fisher's exact test, chi2 test for trends, Kaplan-Meier analysis, and Cox's regression were applied.

RESULTS

In colorectal cancer, 58.6% and 30.6% of cases showed strong cytoplasmic and membranous expression of ALCAM, respectively. No significant correlation with patient age, tumour grade, stage, or nodal status was apparent. In survival analyses, membranous ALCAM expression correlated significantly (Cox's regression, p=0.028; relative risk, 2.3) with shortened patient survival.

CONCLUSIONS

ALCAM is frequently upregulated in colorectal cancer and is a new independent prognostic marker, underscoring the importance of ALCAM in tumour progression in this disease.

The clinical value of ultrasonic tissue characterization in the management of heart transplant patients

The purpose of this study was to evaluate the rejection process by ultrasonic tissue characterization. Serial 2D echocardiographic images were obtained within 24 h prior to an endomyocardial biopsy. The end-diastolic echoframes were digitized into a computer matrix. A region of interest was placed into the anteroseptal segment of each scan. Image texture was analysed by four major groups of texture analysis (first-order histogram, co-occurrence matrix, run-length statistic, power spectrum). In 23 patients, 408 biopsies were taken after each examination, so that correlation between the ultrasonic tissue measurements and the histological state of the tissue could be determined. When rejection occurred, heterogeneity, brightness and contrast of texture increased. Of 117 texture parameters originally claculated, three parameters (inverse difference moment, run-length non-uniformity, ring sums of power spectrum) that characterized rejection were determined by means of discriminance analysis. Compared with biopsy findings, echocardiographic sensitivity for moderate rejection was 93.3% and specifity 83.6%. Our study indicates that acute rejection is associated with changes in echocardiographic texture. Serial echocardiographic texture analysis can reliably identify heart transplant rejection.

Measuring left ventricular function after heart transplantation via digitization of M-mode echocardiograms

The aim of the study was to assess the usefulness of M-mode echocardiography for noninvasive diagnosis of cardiac rejection. For this purpose, 292 M-mode images of 26 heart transplant recipients were analyzed. The echocardiographic images were digitized into an image analysis system. The curves of left ventricular diameter changes were obtained and its first differential calculated. A total of 23 parameters were measured. The most important parameters were: peak velocity of systolic diameter change, peak velocity of diastolic diameter change, time to peak velocity of systolic diameter change, time to peak velocity of diastolic diameter change (TPEAK-D), isovolumetric relaxation time (IVRT), rapid filling time (RFT), shortening fraction (SF), and mean velocity of circumferential fiber shortening (MVCF). The echocardiographic parameters were compared to biopsy results. In 18 patients, 23 biopsy-proven moderate rejections occurred. When rejection occurred, IVRT decreased 23% +/- 6% (P < 0.05), SF decreased 13% +/- 14% (P<0.05), MVCF decreased 18% +/- 18% (P<0.05), and TPEAK-D increased 27% +/- 27% (P<0.05). We concluded that the analysis of digitized M-mode images can identify heart transplant rejection.

Clinical value of echocardiographic tissue characterization in the diagnosis of myocarditis

Inflammatory changes in the myocardium have been visually observed as alterations on echocardiograms. The goal of this study was to determine how these myocardial changes affect the texture of echocardiographic images, and how these could be described through quantitative texture analysis. The results of 142 endomyocardial biopsies were compared with those of texture analysis in echocardiograms of 106 patients suspected of having myocarditis. There were 52 cases of biopsy-proven acute myocarditis, 12 of persistent myocarditis, nine of healed myocarditis without fibrosis, 17 of healed myocarditis with fibrosis, and 35 cases of cardiomyopathy. Eight myocardial biopsies exhibited no pathological changes and nine patients had other cardiac problems. The echocardiograms of a control group of 24 healthy subjects were also evaluated by texture analysis. Three texture parameters were able to differentiate between normal and abnormal myocardium. The mean grey value, i.e. average brightness, was appreciably higher in cases of myocarditis than in control subjects, whereas one co-occurrence and one run length feature had markedly decreased. We conclude that myocarditis and fibrosis induce changes in echocardiographic image texture, i.e. increases in brightness, heterogeneity, and contrast. Performing digital image texture analysis of echocardiograms makes it possible to distinguish between myocarditis and normal myocardium.

Circadian rhythms of dopamine and cholecystokinin in nucleus accumbens and striatum of rats--influence on dopaminergic stimulation

The concentrations of cholecystokinin (CCK) and dopamine (DA) were determined in the nucleus accumbens (anterior, posterior) and striatum of rats every 2 h during a period of 24 h. For both substances, a circadian rhythm was found, which was best fitted by a dominant 24-h period superimposed by the second (12 h) and fourth (6 h) harmonics. The rhythms in CCK and DA were negatively correlated because of a difference in phase position by approximately 3 h. A dominant DA peak was found in the light phase coinciding with a trough in CCK and vice versa in the dark phase. Based on these data, CCK and DA were determined in rats treated with gamma-butyrolactone (GBL; inhibitor of DA release) or thyrotropin-releasing hormone (TRH; stimulator of DA release) at 0900 h or 1300 h to study a putative time-dependency in drug effects. After GBL treatment, CCK as well as DA increased by up to 200% whereas TRH administration led to a rather complex alteration, inasmuch as CCK was increased or decreased, depending on circadian time, whereas the rhythmic pattern in DA remained relatively unaffected. Comparing the drug effects obtained at 0900 h with the response seen at 1300 h revealed significant quantitative as well as qualitative differences. The results demonstrate that the neurotransmission system investigated changed its level of activity depending on time of day. No changes were obtained that convincingly may be ascribed to colocalization of DA and CCK. It is concluded that the chronobiological data indicate a close interaction of CCK and DA in various areas of the rat brain, independent of colocalization.

Noninvasive diagnosis of cardiac rejection through echocardiographic tissue characterization

Ultrasonic tissue characterization is based on the assumption that microscopic tissue structures are identifiable by their acoustic properties. Our study group consisted of 23 cardiac recipients. Two-dimensional images were obtained within 2 hours of endomyocardial biopsy. The end-diastolic echo frames were digitized into the matrix of an image-processing system. A region of interest was placed into the anteroseptal segment of the left ventricle. The texture within the region of interest was analyzed using four major groups of texture analysis (first-order histogram, co-occurrence matrix, run-length statistic, and power spectrum). A total of 408 echocardiographic examinations were compared with histologic findings. The 117 initially calculated texture parameters were reduced incrementally using a series of discriminant analyses. A set of three texture parameters (inverse difference moment undirected, run-length nonuniformity vertical, and sector sum) was able to describe changed echocardiographic texture when rejection occurred. Using these three parameters, echocardiographic sensitivity was 89.0% and specificity was 83.6% for moderate rejection. We conclude that cardiac rejection is associated with echocardiographic texture alterations and that serial echocardiographic texture analysis can reliably identify rejection.

Correlative circadian rhythms of cholecystokinin and dopamine content in nucleus accumbens and striatum of rat brain

Due to contrary results concerning the interaction of cholecystokinin and dopamine (CCK/DA) circadian variations in CCK/DA concentration were investigated in forebrain nuclei of rats (Nc. accumbens, striatum) in order to assess the influence of time of day on neurotransmission. CCK was determined by a radioimmunoassay, DA was measured by electrochemical detection after HPLC separation. A distinct circadian rhythm, superimposed by harmonics (12 h, 6 h) was found in the content of both DA and CCK. A trough was shown for CCK during the light phase and a crest during the late afternoon and the dark phase, respectively. For DA the opposite was found. Caused by a phase-shift of about 3-4 h, the CCK/DA rhythms are negatively correlated. The differences are significant at 11.00 h, 13.00 h, 21.00 h, and 03.00 h. The results indicate that circadian processes are involved in neuronal transmission of CCK and DA.