Allergic Rhinitis and its Impact on Asthma update (ARIA 2008). The perspective from Spain

Allergic rhinitis is a global health problem. Over 600 million patients suffer from this disease worldwide. ARIA (Allergic Rhinitis and its Impact on Asthma), an evidence-based document, was produced and published in 2001 using an extensive review of the available literature. The ARIA 2008 update was recently published and covers tertiary prevention of allergy, pharmacologic treatments, and immunotherapy. Nonallergic rhinitis is still a controversial area and may pose some treatment problems. Another important aspect of the ARIA update is the comorbidity of allergic rhinitis, in particular, asthma. The recommendations of the 2008 ARIA Update, as in 2001, are that patients with allergic rhinitis, particularly if persistent, should be evaluated for asthma, patients with asthma should be evaluated for rhinitis, and an effective and safe combination strategy should be used to treat diseases of the upper and lower airways. Over the last few years, severa studies performed in Spain report new data on the prevalence of allergic rhinitis sensitivity to common aeroallergens, comorbidity of allergic rhinitis and asthma, and impact on quality of life. The studies reviewed in this manuscript confirm--as do those from other developed countries--the enormous impact of the disease on society and health care in Spain.

Sensitization to tomato peel and pulp extracts in the Mediterranean Coast of Spain: prevalence and co-sensitization with aeroallergens

BACKGROUND

Tomatoes (Lycopersicon esculentum) are consumed world-wide. The prevalence of sensitization to tomatoes remains unknown.

OBJECTIVE

To determine the prevalence of skin test reactivity to tomato and to describe the characteristics of tomato-sensitized subjects.

METHODS

Individuals attending for the first time during the period of the study to six Allergy centres, located along the Mediterranean coast of Spain, reporting respiratory and/or cutaneous symptoms, were included. All patients were skin prick tested with a battery of inhalant allergens and with peel and pulp of Canary tomato extracts.

RESULTS

The study included 1734 individuals (757 males, 977 females; 31.9+/-17.8 years old). The prevalence of sensitization to tomato was 6.52% (113 patients; 65 males, 48 females; 29.5+/-13 years old). The peel extract was positive in 110 patients and the pulp extract in 47 patients; three patients were positive exclusively to pulp. Only 1.8% of individuals reported symptoms with tomato; 44% of them had skin test negative to both extracts. Among tomato-sensitized subjects, 16% reported symptoms with tomato, 97% were sensitized to inhalant aeroallergens, including 84% to pollens (mainly Artemisia vulgaris and Platanus hybrida), with differences between Northern and Southern centres.

CONCLUSIONS

The prevalence found of skin test sensitivity to tomato is high. Peel extracts detected most of the sensitized subjects. Most of the sensitized subjects were asymptomatic and some patients reported symptoms without skin test sensitivity. Positive subjects were very frequently sensitized to pollens, suggesting allergen cross-reactivity. Regional differences may exist, possibly related to the pattern of sensitization to cross-reacting pollens.

Development and validation of a new Spanish instrument to measure health-related quality of life in patients with allergic rhinitis: the ESPRINT questionnaire

OBJECTIVES

To develop and validate an instrument to measure health-related quality of life (HRQOL) specific to patients with allergic rhinitis (AR) and primarily for use in Spanish and Spanish-speaking populations.

METHODS

An initial item pool was generated from literature review, focus groups with AR patients, and consultations with clinical experts. Item reduction was performed using clinimetric and psychometric approaches after administration of the item pool to 400 AR patients. The resulting instrument's internal consistency, test-retest (2-4 weeks) reliability, known groups and convergent validity, and sensitivity to change were tested in a longitudinal, observational, multicenter study in 210 AR patients who also completed the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ).

RESULTS

The new questionnaire took a mean (SD) of 7.1 (5.4) minutes to answer. Floor and ceiling effects were less than 15% on all dimensions. Cronbach's alpha values and intraclass correlation coefficient values for six of the sevendimensions and the overall score exceeded 0.70. Statistically significant differences (P < 0.01) were observed on all ESPRINT-28 dimensions and the overall score between patients with mild (mean overall score 1.97, SD 0.99), moderate (mean overall score 2.78, SD 0.88), and severe AR (mean overall score 3.89, SD 0.87). Patients with persistent AR had worse scores (P < 0.05) on all dimensions than patients with intermittent AR. Correlations between the ESPRINT-28 and the RQLQ were generally as expected. Effect sizes for score changes between the two study visits ranged from 0.96 to 1.76 for individual dimensions and the overall score.

CONCLUSIONS

This new, Spanish-developed instrument to measure HRQOL in AR patients has shown good reliability, validity, and sensitivity to change. It has also proved easy to use and administer.

An observational study on outgrowing food allergy during non-birch pollen-specific, subcutaneous immunotherapy

BACKGROUND

Birch pollen-specific immunotherapy (SIT) decreases allergy to foods containing birch pollen-homologous allergens. Cross-reactivity was also observed between plane tree pollen and some vegetable foods.

OBJECTIVE

The aim of this study was to evaluate the outgrowing of food allergy by patients suffering from vegetable food allergy associated with plane tree pollinosis (rhinoconjunctivitis and/or asthma) during plane tree pollen SIT.

METHODS

An observational and prospective study was conducted in 16 adult patients suffering from vegetable food allergy (hazelnut, walnut, lettuce, peach and cherry) and from plane tree pollinosis receiving plane tree pollen SIT for 1 year. Open oral challenges with the implicated food were performed before and after SIT. Blood samples were drawn for measurement of pollen- and food-specific IgE and IgG4 before and after treatment.

RESULTS

Plane tree SIT resulted in a significant decrease in food allergy, since the mean food quantity provoking objective symptoms increased from 2.19 to 13.74 g (p < 0.05), and 6 of the 11 patients tolerated the highest level (25 g) of the challenged food after plane tree SIT. Laboratory data also showed a decrease in IgE levels and an increase in IgG4 levels after immunotherapy.

CONCLUSION

SIT with plane tree pollen has a positive impact on food allergy in plane tree pollen-allergic subjects.

Allergic rhinitis: continuous or on demand antihistamine therapy?

Allergic rhinitis is an inflammatory disease of the nasal mucosa, caused by an IgE-mediated reaction after exposure to the allergen to which the patient is sensitized. Histamine is the most important preformed mediator released in the early stage of the allergic reaction, and also contributes to the late phase of the latter, exhibiting proinflammatory effects. Minimal persistent inflammation is a physiopathological phenomenon induced by the presence of an inflammatory cell infiltrate, together with ICAM-1 expression in the epithelial cells of the mucosa exposed to the allergen to which they are sensitized, in the absence of clinical symptoms. This molecule is considered to be an allergic inflammatory marker. The priming effect first described by Connell in 1968 consists of the reduction in the allergen concentration required to elicit a nasal hyper-response when performing a daily nasal exposure test. This implies that with natural exposure to inhaled allergens, small amounts of environmental allergen will maintain the patient symptoms, and thus of course minimal persistent inflammation. Considering the above, it is questionable whether antihistamines should be administered on a continuous basis or upon demand. The antihistamines, and fundamentally the second-generation drugs, have been shown to exert an antiinflammatory effect, and this effect is greater when the drug is administered continuously than when administered upon demand. Likewise, a reduction in treatment cost and an improvement in quality of life among patients treated on a continuous basis has been documented. However, no studies have been specifically designed to clarify the indication of treatment on a continuous basis or upon demand, as occurs in the GINA. As a result, the individualization of treatment according to the concrete characteristics of each patient seems to be the best approach, at least for the time being.

Air pollution and allergens

It is well known that the prevalence of allergic diseases has increased in recent decades in the industrialized world. Exposure to environmental pollutants may partially account for this increased prevalence. In effect, air pollution is a growing public health problem. In Europe, the main source of air pollution due to particles in suspension is represented by motor vehicles--particularly those that use diesel fuel. Diesel exhaust particles (DEPs) are composed of a carbon core upon which high-molecular weight organic chemical components and heavy metals deposit. Over 80% of all DEPs are in the ultrafine particle range (< 0.1 pm in diameter). Air pollutants not only have a direct or indirect effect upon the individual, but also exert important actions upon aeroallergens. Pollen in heavily polluted zones can express a larger amount of proteins described as being allergenic. Through physical contact with the pollen particles, DEPs can disrupt the former, leading to the release of paucimicronic particles and transporting them by air--thus facilitating their penetration of the human airways. Climate change in part gives rise to variations in the temperature pattern characterizing the different seasons of the year. Thus, plants may vary their pollination calendar, advancing and prolonging their pollination period. In addition, in the presence of high CO2 concentrations and temperatures, plants increase their pollen output. Climate change may also lead to the extinction of species, and to the consolidation of non-native species--with the subsequent risk of allergic sensitization among the exposed human population. In conclusion, there is sufficient scientific evidence on the effect of air pollution upon allergens, increasing exposure to the latter, their concentration and/or biological allergenic activity.

Use of antihistamines in pediatrics

Drugs with antihistamine action are among the most commonly prescribed medicines in pediatrics. According to the International Medical Statistics (IMS), almost two million antihistamine units (in solution) for pediatric use were sold in Spain during 2006--at a cost of nearly 6 million euros. Of this amount, 34% corresponded to first-generation (or sedating) antihistamines. The difficulties inherent to research for drug development increase considerably when the pediatric age range is involved. The use of any medication in this age group must adhere to the strictest safety criteria, and must offer the maximum guarantees of efficacy. For this reason, detailed knowledge of the best scientific evidence available in relation to these aspects is essential for warranting drug use. The first-generation antihistamines have never been adequately studied for pediatric age groups, though they are still widely used in application to such patients. In contrast, studies in children have been made with the second-generation antihistamines, allowing us to know their safety profile, and such medicines are available at pediatric dosages that have been well documented from the pharmacological perspective. The present review affords an update to our most recent knowledge on antihistamine use in children, based on the best scientific evidence available.

Effects on nasal nitric oxide production of 2 mechanisms of vasoconstriction

BACKGROUND

Vasoconstrictor drugs reduce nitric oxide (NO) production in vitro by inhibiting the enzyme involved in the regulation of inducible and constitutive NO synthases (iNOS and cNOS). Intranasal vasoconstrictors also decrease nasal NO concentration in vivo. It is as yet unclear if this last finding is due to the effects of the drug on the enzyme or on the vessels. Physical exercise also induces nasal vasoconstriction and reduces nasal resistance.

OBJECTIVES

The aim of this study was to clarify the mechanisms involved in xylometazoline-induced reduction of nasal NO concentration.

METHODS

We compared 2 randomized groups of patients with moderate--severe persistent allergic rhinitis. The first group (n = 24) underwent a physiological nasal vasoconstrictor stimulus (exercise) whereas the second group (n = 29) was treated with a nasal vasoconstrictor drug (topical xylometazoline). Nasal volume and NO were determined at baseline and 15 to 20 minutes after the end of each stimulus using acoustic rhinometry and chemiluminescence, respectively.

RESULTS

Baseline values of nasal volume and NO did not differ between the 2 groups. Nasal volume increased by 57% (P = .0001) after exercise and 71% (P = .0001) after xylometazoline. Nasal NO decreased (25%, P = .001) after xylometazoline, but not after exercise.

CONCLUSION

Physical exercise and topical xylometazoline cause vasoconstriction and similar effects on nasal volume. In contrast nasal NO decreased with xylometazoline but not after exercise. These findings suggest that vasoconstrictor drugs reduce nasal NO by mechanisms other than vasoconstriction.

Antihistamines in the treatment of chronic urticaria

Chronic urticaria is highly prevalent in the general population, and while there are multiple treatments for the disorder, the results obtained are not completely satisfactory. The second-generation H1 antihistamines remain the symptomatic treatment option of choice. Depending on the different pharmacokinetics and H1 receptor affinity of each drug substance, different concentrations in skin can be expected, together with different efficacy in relation to the histamine-induced wheal inhibition test--though this does not necessarily have repercussions upon clinical response. The antiinflammatory properties of the H1 antihistamines could be of relevance in chronic urticaria, though it is not clear to what degree they influence the final therapeutic result. Before moving on to another therapeutic level, the advisability of antihistamine dose escalation should be considered, involving increments even above those approved in the Summary of Product Characteristics. Physical urticaria, when manifesting isolatedly, tends to respond well to H1 antihistamines, with the exception of genuine solar urticaria and delayed pressure urticaria. In some cases of chronic urticaria, the combination of H2 antihistamines may prove effective--though only with common liver metabolism (CYP3A4 isoenzyme-mediated) H1 antihistamines, due to the existence of mutual metabolic interferences. The role of leukotriene antagonists associated to antihistamines in application to chronic urticaria remains to be clearly defined.

Effect of pollutants upon patients with respiratory allergies

Epidemiological studies have revealed an association between pollution and allergic respiratory diseases. The main pollutants in this sense are nitric oxide, ozone, and particulate matter. The present review on one hand addresses the chemical characteristics of each of these three groups of pollutants and their main sources, and on the other examines their effects upon allergic respiratory diseases--placing special emphasis on the effects of diesel exhaust particles. For each of the pollutants, the underlying mechanisms capable of influencing allergic respiratory diseases are commented. Lastly, an evaluation is made of some of the genetic aspects related to the response to pollutants.

Drug neosensitization during anticonvulsant hypersensitivity syndrome

Anticonvulsant hypersensitivity syndrome (AHS) is a rare, severe drug hypersensitivity reaction included in the drug-related rash with eosinophilia and systemic symptoms syndrome (DRESS), in which a transient state of immune suppression and reactivation of latent virus infections have been observed. We describe 5 patients who developed neosensitization to different drugs taken during a previous episode of anticonvulsant-related DRESS, in whom skin prick, intradermal and/or patch tests were performed to confirm the diagnosis of drug hypersensitivity. In 1 patient, transient hypogammaglobulinemia was observed during the AHS. Four of the 5 patients developed a delayed skin eruption or a delayed systemic hypersensitivity reaction after intake of a drug that they had also taken during a previous anticonvulsant DRESS which had occurred months or years earlier; in the fifth, a possible reaction was prevented thanks to the allergy workup. The diagnosis of drug allergy was demonstrated by positive delayed reaction to intradermal test with amoxicillin in 2 cases, positive patch tests to paracetamol and amitriptyline in 2 cases, and by clinical evidence of ceftriaxone erythroderma in one. The possibility of neosensitization to drugs administered during anticonvulsant-related DRESS should be considered. A transient state of immunosuppression induced during the anticonvulsant-related DRESS may trigger latent virus reactivation and massive nonspecific immune system response, which may lead to breakdown of tolerance to other drugs present at that time in the organism.

IgE reactivity to profilin in Platanus acerifolia pollen-sensitized subjects with plant-derived food allergy

BACKGROUND

The presence of profilin-specific IgE antibodies is a cause of cross-reactivity between botanically-unrelated allergen sources. Recently, the association between Platanus acerifolia pollinosis and plant-derived food allergy has been described. The aim of this study was to ascertain whether the P. acerifolia profilin is involved in such cross-reactivity.

METHODS

Twenty-three patients suffering from Platanus acerifolia pollinosis and plant-derived food allergy were evaluated in an allergy department. Specific IgE levels to P. acerifolia pollen, P. acerifolia profilin and food extracts were measured. Molecular masses of IgE-binding proteins were calculated by Western blotting and cross-reactivity studies among P. acerifolia profilin and different food extracts were evaluated by Enzyme AllergoSorbent Test (EAST)-inhibition assays. Also, EAST-inhibition assays with the two known P. acerifolia allergens, Pla a 1 and Pla a 2, were performed.

RESULTS

Surprisingly, a high IgE-binding prevalence (90%) of P. acerifolia profilin was found. EAST-inhibition showed high inhibition values when Platanus acerifolia pollen extract was used as free phase and plant-derived food extracts as solid phase, whereas the other way round showed low inhibition values. IgE reactivity to profilin was studied using a pool of patient sera, by EAST-inhibition assays with hazelnut, apple peel, peanut, chickpea and peanut extracts as solid phase and no inhibition was obtained when P. acerifolia profilin was used as inhibitor phase. The same results were obtained when purified Pla a 1 and Pla a 2 were also used as inhibitor phase.

CONCLUSIONS

The clinical association observed between Platanus acerifolia pollen and plant-derived food could be explained by the in vitro IgE cross-reactivity detected by EAST-inhibition. However, it appears that neither P. acerifolia profilin nor the two major allergens described (Pla a 1 and Pla a 2) can explain such a strong cross-reactivity.

Allergic eosinophilic gastroenteritis in a child with Crohn's disease

A case of a child with Crohn's disease who developed an eosinophilic gastroenteritis is reported. Although symptoms of eosinophilic gastroenteritis at age 8 could mimic those of Crohn's disease, laboratory, radiographic and histologically studies are clearly different. Peripheral blood eosinophilia (7,476 cells per mm3), high serum IgE level (1,050 kU/l) and normal C-reactive protein and erythrocyte sedimentation rate are common in eosinophilic gastroenteritis and uncommon in Crohn's disease. Eosinophilic gastroenteritis was due to bovine serum albumin (BSA) hypersensitivity, confirmed with skin tests, serum levels to specific IgE and a SDS-PAGE IgE-immunoblotting. A strict meat-free diet was started, with progressive relief of symptoms and decrease of eosinophil count twelve months later; the patient became fully symptom-free and eosinophil count was normal.

Effects of specific immunotherapy on the development of new sensitisations in monosensitised patients

BACKGROUND

Specific immunotherapy (SIT) is the only treatment that interferes with the basic pathophysiological mechanisms of allergic disease and is widely used in the management of clinically significant respiratory IgE-mediated diseases. Nevertheless, until recently, information on the influence of SIT on the development of new allergic sensitisations has been scant.

METHODS

One hundred consecutive patients (45 males and 55 females, aged 6 to 69 years) with respiratory allergic diseases and attending the allergy unit of a general hospital were selected. All had been diagnosed by clinical history and skin prick tests of allergic rhinitis and/or asthma, were monosensitised (71 to Dermatophagoides spp, 22 to Parietaria judaica pollen and 7 to grass pollen) and had been followed up as outpatients between 1990-98. Sixty-six patients had been treated with conventional SIT for at least 3 years, while thirty-four followed only environmental measures and drug treatment. Family atopy status (first-degree relatives), smoking, family pets (cat and/or dog), rhinitis and/or asthma symptom score and inhalant skin prick tests to the same aeroallergens were compared between baseline and after 3 to 5 years of treatment.

RESULTS

No statistically-significant differences in the development of new sensitisations were observed between the two groups (36.4 % of SIT-treated patients versus 38.2 % in control group, RR = 0.97, CI 95 %: 0.72-1.3). Smoking, family atopy history and pets did not appear to be risk factors for the development of neosensitisations (p < 0.05). Nevertheless, SIT-treated patients presented a better clinical score than the control group, with improvements of 89.4 % and 61.8 %, respectively (p = 0.007).

CONCLUSIONS

Three-year SIT did not protect against development of new sensitisations in monosensitised allergic rhinitis or asthma. Smoking, family atopy history and pets were not associated with development of new sensitisations. Clinical score improved significantly in the SIT-treated group compared with drug-treated patients.

Urticaria to cetirizine

A patient with recurrent idiopathic urticaria reported exacerbations after treatment with cetirizine. Prick test to cetirizine was negative. Double-blind challenge tests with mizolastine, loratadine, fexofenadine, dexchlorpheniramine, ebastine, ketotifen, and placebo were negative, whereas hydroxyzine and its active metabolite, cetirizine, reproduced the urticaria. Identification of uncommon adverse reactions to H1 antihistamines is important, particularly because they may mimic the underlying disease.