Matthias V. Kopp

Randomized, Double-Blind, Placebo-Controlled Trial of Probiotics for Primary Prevention: No Clinical Effects of Lactobacillus GG Supplementation

BACKGROUND. The value of probiotics for primary prevention is controversial. Published trials vary considerably in study design and the applied probiotics, thereby limiting comparability of the results. OBJECTIVE. The purpose of this trial was to study the preventive effect of the probiotic Lactobacillus GG on the development of atopic dermatitis. METHODS. In a double-blind, placebo-controlled prospective trial, 105 pregnant women from families with ≥1 member (mother, father, or child) with an atopic disease were randomly assigned to receive either the probiotic Lactobacillus GG (American Type Culture Collection 53103; 5 × 109 colony-forming units of Lactobacillus GG twice daily) or placebo. Ninety-four families (89.5%) completed the trial. The supplementation period started 4 to 6 weeks before expected delivery, followed by a postnatal period of 6 months. The primary end point was the occurrence of atopic dermatitis at the age of 2 years. Secondary outcomes were severity of atopic dermatitis, recurrent episodes of wheezing bronchitis, and allergic sensitization at the age of 2 years. RESULTS. Atopic dermatitis was diagnosed in 14 (28%) of 50 in the Lactobacillus GG group and in 12 (27.3%) of 44 in the placebo group. The risk of atopic dermatitis in children on probiotics relative to placebo was 0.96 (confidence interval 0.38–2.33). Severity of atopic dermatitis was comparable between the 2 groups. Notably, children with recurrent (≥5) episodes of wheezing bronchitis were more frequent in the Lactobacillus GG group (26%; n = 13), as compared with the placebo group (9.1%; n = 4). No difference was observed between both groups in total immunoglobulin E concentrations or numbers of specific sensitization to inhalant allergens. CONCLUSIONS. Supplementation with Lactobacillus GG during pregnancy and early infancy neither reduced the incidence of atopic dermatitis nor altered the severity of atopic dermatitis in affected children but was associated with an increased rate of recurrent episodes of wheezing bronchitis. Therefore, Lactobacillus GG cannot be generally recommended for primary prevention.

Guideline on allergen-specific immunotherapy in IgE-mediated allergic diseases

SummaryThe present guideline (S2k) on allergen-specific immunotherapy (AIT) was established by the German, Austrian and Swiss professional associations for allergy in consensus with the scientific specialist societies and professional associations in the fields of otolaryngology, dermatology and venereology, pediatric and adolescent medicine, pneumology as well as a German patient organization (German Allergy and Asthma Association; Deutscher Allergie- und Asthmabund, DAAB) according to the criteria of the Association of the Scientific Medical Societies in Germany (Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften, AWMF).AIT is a therapy with disease-modifying effects. By administering allergen extracts, specific blocking antibodies, toler-ance-inducing cells and mediators are activated. These prevent further exacerbation of the allergen-triggered immune response, block the specific immune response and attenuate the inflammatory response in tissue.Products for SCIT or SLIT cannot be compared at present due to their heterogeneous composition, nor can allergen concentrations given by different manufacturers be compared meaningfully due to the varying methods used to measure their active ingredients. Non-modified allergens are used for SCIT in the form of aqueous or physically adsorbed (depot) extracts, as well as chemically modified allergens (allergoids) as depot extracts. Allergen extracts for SLIT are used in the form of aqueous solutions or tablets.The clinical efficacy of AIT is measured using various scores as primary and secondary study endpoints. The EMA stipulates combined symptom and medication scores as primary endpoint. A harmonization of clinical endpoints, e. g., by using the combined symptom and medication scores (CSMS) recommended by the EAACI, is desirable in the future in order to permit the comparison of results from different studies. The current CONSORT recommendations from the ARIA/GA2LEN group specify standards for the evaluation, presentation and publication of study results.According to the Therapy allergen ordinance (TAV), preparations containing common allergen sources (pollen from grasses, birch, alder, hazel, house dust mites, as well as bee and wasp venom) need a marketing authorization in Germany. During the marketing authorization process, these preparations are examined regarding quality, safety and efficacy. In the opinion of the authors, authorized allergen preparations with documented efficacy and safety, or preparations tradeable under the TAV for which efficacy and safety have already been documented in clinical trials meeting WAO or EMA standards, should be preferentially used. Individual formulations (NPP) enable the prescription of rare allergen sources (e.g., pollen from ash, mugwort or ambrosia, mold Alternaria, animal allergens) for specific immunotherapy. Mixing these allergens with TAV allergens is not permitted.Allergic rhinitis and its associated co-morbidities (e. g., bronchial asthma) generate substantial direct and indirect costs. Treatment options, in particular AIT, are therefore evaluated using cost-benefit and cost-effectiveness analyses. From a long-term perspective, AIT is considered to be significantly more cost effective in allergic rhinitis and allergic asthma than pharmacotherapy, but is heavily dependent on patient compliance.Meta-analyses provide unequivocal evidence of the efficacy of SCIT and SLIT for certain allergen sources and age groups. Data from controlled studies differ in terms of scope, quality and dosing regimens and require product-specific evaluation. Therefore, evaluating individual preparations according to clearly defined criteria is recommended. A broad transfer of the efficacy of certain preparations to all preparations administered in the same way is not endorsed. The website of the German Society for Allergology and Clinical Immunology (www.dgaki.de/leitlinien/s2k-leitlinie-sit; DGAKI: Deutsche Gesellschaft für Allergologie und klinische Immunologie) provides tables with specific information on available products for AIT in Germany, Switzerland and Austria. The tables contain the number of clinical studies per product in adults and children, the year of market authorization, underlying scoring systems, number of randomized and analyzed subjects and the method of evaluation (ITT, FAS, PP), separately given for grass pollen, birch pollen and house dust mite allergens, and the status of approval for the conduct of clinical studies with these products.Strong evidence of the efficacy of SCIT in pollen allergy-induced allergic rhinoconjunctivitis in adulthood is well-documented in numerous trials and, in childhood and adolescence, in a few trials. Efficacy in house dust mite allergy is documented by a number of controlled trials in adults and few controlled trials in children. Only a few controlled trials, independent of age, are available for mold allergy (in particular Alternaria). With regard to animal dander allergies (primarily to cat allergens), only small studies, some with methodological deficiencies are available. Only a moderate and inconsistent therapeutic effect in atopic dermatitis has been observed in the quite heterogeneous studies conducted to date. SCIT has been well investigated for individual preparations in controlled bronchial asthma as defined by the Global Initiative for Asthma (GINA) 2007 and intermittent and mild persistent asthma (GINA 2005) and it is recommended as a treatment option, in addition to allergen avoidance and pharmacotherapy, provided there is a clear causal link between respiratory symptoms and the relevant allergen.The efficacy of SLIT in grass pollen-induced allergic rhinoconjunctivitis is extensively documented in adults and children, whilst its efficacy in tree pollen allergy has only been shown in adults. New controlled trials (some with high patient numbers) on house dust mite allergy provide evidence of efficacy of SLIT in adults.Compared with allergic rhinoconjunctivitis, there are only few studies on the efficacy of SLIT in allergic asthma. In this context, newer studies show an efficacy for SLIT on asthma symptoms in the subgroup of grass pollen allergic children, adolescents and adults with asthma and efficacy in primary house dust mite allergy-induced asthma in adolescents aged from 14 years and in adults.Aspects of secondary prevention, in particular the reduction of new sensitizations and reduced asthma risk, are important rationales for choosing to initiate treatment early in childhood and adolescence. In this context, those products for which the appropriate effects have been demonstrated should be considered.SCIT or SLIT with pollen or mite allergens can be performed in patients with allergic rhinoconjunctivitis using allergen extracts that have been proven to be effective in at least one double-blind placebo-controlled (DBPC) study. At present, clinical trials are underway for the indication in asthma due to house dust mite allergy, some of the results of which have already been published, whilst others are still awaited (see the DGAKI table “Approved/potentially completed studies” via www.dgaki.de/Leitlinien/s2k-Leitlinie-sit (according to www.clinicaltrialsregister.eu)). When establishing the indication for AIT, factors that favour clinical efficacy should be taken into consideration. Differences between SCIT and SLIT are to be considered primarily in terms of contraindications. In individual cases, AIT may be justifiably indicated despite the presence of contraindications.SCIT injections and the initiation of SLIT are performed by a physician experienced in this type of treatment and who is able to administer emergency treatment in the case of an allergic reaction. Patients must be fully informed about the procedure and risks of possible adverse events, and the details of this process must be documented (see “Treatment information sheet”; available as a handout via www.dgaki.de/Leitlinien/s2k-Leitlinie-sit). Treatment should be performed according to the manufacturer‘s product information leaflet. In cases where AIT is to be performed or continued by a different physician to the one who established the indication, close cooperation is required in order to ensure that treatment is implemented consistently and at low risk. In general, it is recommended that SCIT and SLIT should only be performed using preparations for which adequate proof of efficacy is available from clinical trials.Treatment adherence among AIT patients is lower than assumed by physicians, irrespective of the form of administration. Clearly, adherence is of vital importance for treatment success. Improving AIT adherence is one of the most important future goals, in order to ensure efficacy of the therapy.Severe, potentially life-threatening systemic reactions during SCIT are possible, but – providing all safety measures are adhered to – these events are very rare. Most adverse events are mild to moderate and can be treated well.Dose-dependent adverse local reactions occur frequently in the mouth and throat in SLIT. Systemic reactions have been described in SLIT, but are seen far less often than with SCIT. In terms of anaphylaxis and other severe systemic reactions, SLIT has a better safety profile than SCIT.The risk and effects of adverse systemic reactions in the setting of AIT can be effectively reduced by training of personnel, adhering to safety standards and prompt use of emergency measures, including early administration of i. m. epinephrine. Details on the acute management of anaphylactic reactions can be found in the current S2 guideline on anaphylaxis issued by the AWMF (S2-AWMF-LL Registry Number 061-025).AIT is undergoing some innovative developments in many areas (e. g., allergen characterization, new administration routes, adjuvants, faster and safer dose escalation protocols), some of which are already being investigated in clinical trials.Cite this as Pfaar O, Bacher

The impact of probiotics and prebiotics on the immune system

Probiotics and prebiotics are increasingly being added to foodstuffs with claims of health benefits. Probiotics are live microorganisms that are thought to have beneficial effects on the host, whereas prebiotics are ingredients that stimulate the growth and/or function of beneficial intestinal microorganisms. But can these products directly modulate immune function and influence inflammatory diseases? Here, Nature Reviews Immunology asks four experts to discuss these issues and provide their thoughts on the future application of probiotics as a disease therapy.

Perspectives on allergen‐specific immunotherapy in childhood: An EAACI position statement

To cite this article: Calderon MA, Gerth van Wijk R, Eichler I, Matricardi PM, Varga EM, Kopp MV, Eng P, Niggemann B, Nieto A, Valovirta E, Eigenmann PA, Pajno G, Bufe A, Halken S, Beyer K, Wahn U. Perspectives on allergen‐specific immunotherapy in childhood: An EAACI position statement. Pediatr Allergy Immunol 2012: 23: 300–306.

Lactobacillus GG has in vitro effects on enhanced interleukin‐10 and interferon‐γ release of mononuclear cells but no in vivo effects in supplemented mothers and their neonates

Background The value of probiotics for primary prevention is controversial. Moreover, only little is known about the underlying immunological mechanisms of action. Therefore, we assessed the proliferative response and cytokine release in cultures of isolated mononuclear cells from pregnant women and their neonates supplemented with Lactobacillus GG (LGG) or placebo.

Allergen‐specific T cell reactivity in cord blood: the influence of maternal cytokine production

Background Successful pregnancy is dependent upon T helper (Th)2‐type‐dominated immunological responsiveness in gestation‐associated compartments.

Effect of anti-immunoglobulin E on nasal inflammation in patients with seasonal allergic rhinoconjunctivitis.

Background Binding of allergens to IgE on mast cells and basophils causes release of inflammatory mediators in nasal secretions.

Microbial influence on tolerance and opportunities for intervention with prebiotics/probiotics and bacterial lysates

Epidemiologic studies indicate that microbes and microbial components are associated with protection against chronic inflammatory disease. Consequently, a plethora of clinical approaches have been used to investigate the benefits of a range of microbial products on inflammatory conditions in human trials. Centered particularly on the use of prebiotics, probiotic bacteria, and bacterial lysates in early life, this review provides an overview on clinical approaches aimed at reducing the global burden of allergic disease through primary prevention. Microbial interventions beginning before birth and in early infancy are discussed in the context of underlying mechanisms of oral tolerance and the establishment of gut colonization as a critical early homeostatic influence. We explore both the findings and challenges faced in existing studies with a view toward improving future clinical studies of the application of microbial compounds for the prevention of allergic disease and other inflammatory diseases.

Transient impact of omalizumab in pollen allergic patients undergoing specific immunotherapy

Recently, we showed that combination of omalizumab with specific immunotherapy (SIT) for treatment of patients with seasonal allergic rhinitis (SAR) and comorbid seasonal allergic asthma (SAA) is safe and reduced the symptom load in a statistically significant and clinically meaningful manner during the first pollen season.

Long- and medium-term ozone effects on lung growth including a broad spectrum of exposure

The effects of semi-annual and 3.5 yr mean ozone (O3) concentrations on childrens forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were assessed over a study period of 3.5 yrs in 2,153 schoolchildren from 15 study sites in South Western Germany and Lower Austria. Spirometric parameters were assessed twice a year, and differences between consecutive measurements divided by days were considered as a measure of lung growth. Exposure was analysed in four classes, separately for winter and summer (semi-annual mean O3 concentrations 22–30, 30–38, 38–46, 46–54 parts per billion (ppb) in summer and 4–12, 12–20, 20–28, 28–36 ppb in winter). Regression methods for repeated measurements were used, and these revealed a significantly lower FVC (FEV1) increase estimated at −19.2 (−18.5) mL·100 days−1 for semi-annual mean O3 exposure in summer between 46 and 54 ppb compared to exposure between 22 and 30 ppb. However, in winter, the estimated difference in FVC (FEV1) was 16.4 (10.9) mL·100 days−1 between the semi-annual O3 class 28–36 ppb and the 4–12 ppb class. By means of linear regression the study found that there was no association between growth rates and mean summer O3 for FVC and FEV1 over a 3.5 yr period. The authors conclude that medium-term effects on schoolchildrens lung growth are possibly present, but are in the long-term not detectable for forced vital capacity and forced expiratory volume in one second over a 3.5 yr period due to partial reversibility.