Prevalence of allergy to latex in the pediatric population.

Latex is a substance that is extracted from the plant Hevea Brasiliensis, and world production is 6 million metric tons per year. After gathering it undergoes a series of processes in which ammonia, vulcanization-accelerating additives or anti-oxidants are added. All of this may constitute the antigenic load that latex contains. It is used in medicine for gloves, drainage tubes, dental implants and a growing number of products from condoms to sport products or automobile components. Over fifteen different allergenic bands have been described, with molecular weights of between 2 and 100 kDa. In a joint study, USA-Finland identified three antigenic bands that predominate according to the population type studied (2). In children with spina bifida, congenital urogenital abnormalities or those submitted to multiple surgical interventions, the band of 27 kDa is predominant. This antigen has not been detected in adult serum, which suggests that contact with the antigen is through the mucous membranes and the sensitization is triggered from here. The incidence of allergy to latex in the general population is not known, but it seems to be lower than 1%. Turjanmaa (1) establishes a frequency of 0.125% (1/800) in patients submitted to general surgery. The incidence of sensitization to latex varies according to the population studied. Among the population considered to be at risk are the workers of the health environment, where the incidence is between 2.6 and 16.9%, whereas in the general population the percentage is around 1%. Sensitivity to latex is of great importance in patients suffering from spina bifida, in whom an incidence of between 28 and 67% has been found. We present our experience in a group of children attending our service for the first time for diverse reasons of supposed allergic etiology. The objective is to determine the incidence of sensitization to latex according to the diagnostic methodology [cutaneous test or by determination of specific IgE (CAP)]; according to the type of patient (atopic or non-atopic), the direct relationship with latex material and the role that can be played by a history of surgical intervention. In our experience with 282 children studied in our pediatric allergology service using diverse methods, the incidence of allergy to latex is 3.19%. Nevertheless, if we analyze this percentage we observe that if the diagnosis is based exclusively on cutaneous tests, it is only 1.08%; if to establish a diagnosis we used exclusively the determination of specific IgE (CAP) we would label 7. 2% of our children as allergic. Atopy is a factor that facilitates sensitization. In our sample, the incidence among the atopic population is 4.4%, though this percentage may vary between 1.69% and 9.5% depending on the methodology used. There are several hypotheses for explaining these discrepancies in the diagnostic tests. Although there do not seem to be differences regarding the ammonia content of the different lots, it seems that the differential factor could lie in the type of extract and in whether it is commercial or a natural latex extract. It could be a consequence of the existence of a prophyllin, so it has not been ruled out that a part of the IgE is an antiprophyllin. The presence of different epitopes would mean that each of them has the ability to produce its own specific IgE, though the RAST/CAP was not able to differentiate them and identified them as whole. The rate of allergy to latex in a group of children suffering from myelomeningocele is 80%. At a paediatric level, sensitization to latex is influenced by the means of contact, the duration of the exposure to the antigen and the fact that the exposure occurs early, which in the case of children with myelomeningocele is associated with the immaturity of the defence mechanism of the mucous membranes.

Parietaria allergy in children.

Parietaria, a grassy plant belonging to the Urticaceae family which is commonly found in urban environments, tends to grow on fences, walls and soils with a high content in nitrogen. Since 1983 the Xarxa Aerobiologica de Catalunya (Catalonian Aerobiological Network) has been using Hirst and Court sensors to monitor the daily concentrations of its pollen with respect to the weather conditions (wind, rain, temperature) in various sites in Catalonia and the Balearic Islands. This pollen is present practically all year round in our area, mainly during cold, rainy and seaside areas. Studies at a pediatric level are scarce and this is why we reviewed our data in this field. The study included a total of 12,650 case histories of first time attendances to our Pediatric Allergology Unit; 449 children showed sensitivity to Parietal pollen. Exclusive sensitivity to Parietaria in this age group of 1 and 15 years olds tended to be very low. However, we observed that after initial preferential sensitization to domestic allergens, Parietal pollen became the most frequent cause of sensitivity as the patients grew older. Although rhinoconjunctival manifestations predominate, at least at a pediatric level, the implication of Parietal pollen as a cause of bronchial asthma cannot be ignored.

Allergy to pine nuts in children.

BACKGROUND: Allergy to nuts is a common and well-known disease. Despite the fact that pine nut is a widely eaten food, only nine cases have been described in literature. OBJECTIVE: To describe four paediatric patients suffering from allergy reaction on ingestion of pine nuts and compare them with cases described in literature, taking into account clinical symptoms, epidemiological and diagnostic methods. METHODS: The immuno-allergic study was carried out with skin tests (prick tests) using a commercial and native extract, and specific IgE serum test. An oral provocation test was performed in one case. RESULTS: Ages ranged from 12 months to 6 years. All patients had a personal history of atopy. Symptoms on ingesting pine nut were severe systemic reactions in three cases. Two of the children had allergic reactions to other nuts. In all cases, both the skin test and the specific IgE serum test were positive. The oral provocation was positive in the case for which it was performed. CONCLUSIONS: A typical clinical reaction of immediate hypersensitivity to this nut took place in all four children. The skin tests and in vitro studies confirm an IgE-mediated response. We currently have a commercial prick test for pine nut for the diagnosis, which has proven its sensitivity and specificity. In our region, due to the large consumption, the rate of allergic reactions to pine nuts would probably be greater and earlier on in life than in other areas.

[From atopic dermatitis to asthma]. / De la dermatitis atópica al asma.

The prevalence of atopic dermatitis and other allergic diseases is increasing in industrialized countries. Today we know that atopy is conditioned genetically, but the development of the atopic phenotype requires environmental factors. It is believed that the genetic factors have not changed and that the increased prevalence is due to the increase in exposure to allergenic and non-specific environmental factors. The potential for sensitization is greater in the early years of life, so it is necessary to reduce harmful environmental exposure at these ages. Atopic clinical manifestations develop sequentially, in many cases beginning with atopic dermatitis in the early months of life. We know that children with atopic dermatitis present non-specific bronchial hyperreactivity (58 to 82%), which is a risk factor for the later development of asthma. The presence of specific bronchial hyperreactivity for mites in atopic dermatitis with mite sensitization also has been described, and it has been demonstrated that signs of eczema can develop or become exacerbated by airway exposure during bronchial challenge tests. The evolution from atopic dermatitis to asthma is a possibility that must be kept in mind. Patients should be followed-up and study of hyperreactivity and sensitization to allergens should be carried out in order to prevent the development of clinical symptoms. Prevention should include pneumoallergens, food allergens, and non-specific environmental risk factors, such as parental smoking (particularly mothers), pollution inside and outside the home, etc. Prevention is particularly important in children at risk of allergy, as determined by a family history among first-degree relatives, as well as the presence of atopic dermatitis, particularly of early onset, because these patient are most at risk of developing bronchial asthma in later years. At present, pharmacological prevention is being studied, without overlooking environmental prevention, in children at high risk of atopic disease for the purpose of preventing chronic inflammations that will condition their future as adults. In our daily clinical experience, atopic dermatitis is responsible for 8% of visits to a pediatric allergology unit. We emphasize that 62.5% of our patients with dermatitis are referred when they already have bronchial asthma, which represents an important delay in diagnosis with respect to the onset of symptoms.

[Epidemiology and chronology of allergic diseases and their risk factors]. / Epidemiología y cronología de las enfermedades alérgicas y sus factores de riesgo.

An increase in allergic diseases in Western societies has been observed in all epidemiological studies. Various risk factors have been invoked to explain this increase, but the results are still inconclusive. We examined the type of patients who visited a hospital pediatric allergology unit in terms of the type of pathology presented, environmental factors, and time from the onset of symptoms until referral for allergy study. We evaluated 200 children ranging in age from 1 month to 15 years who were distributed by pathology: 119 referrals for respiratory manifestations (asthma, rhinitis, coughing, ...), 46 for food-related pathology, and 35 for adverse reactions attributed to medications. Among the risk factors, 69% of the children had a family history, 63.5% were exposed to smoking, and all of the patients were from urban and urban-industrial areas. We found no relation between the type of pathology and birth month. The natural history of allergic disease showed the following sequence: food allergy--respiratory allergy--medication allergy. In every case there was an important delay in diagnosis. The patients who visited our department soonest were infants (for presumptive allergy to cow milk protein or suspected adverse reaction to medications). It is evident that in recent years we are seeing a major increase in allergic diseases, particularly in industrialized countries. From a clinical point of view, manifestations such as asthma, rhinitis, and atopic dermatitis are increasing, which all working groups attribute to an increase in the prevalence of allergy. Epidemiological studies of large population samples use non-standard methods, with different selection criteria, ethnic breakdown and geographic differences. This makes it difficult to compare available data. Therefore, we think that it would be advisable if epidemiological studies would attempt to follow a model, which would facilitate the comparison of studies. Our aim was to evaluate the type of patients who required allergy studies in relation to the pathologies that they present and the different diagnostic methods to determine the presence of false allergies or non-allergies, the delay until study, most frequent pathologies, and environment. We report the data obtained from a sample of 200 children who visited our department for the first time in the period of a natural year.

Determination of total and specific IgE using UNICAP 100: comparative study with the CAP system.

The methods of serum determination of specific IgE to different allergens have showed lower diagnostic sensitivity than the alternative in vivo methods, the skin tests. The CAP system from Pharmacia, owing to its solid phase, has ameliorated this disadvantage, showing in various studies greater diagnostic sensitivity than the classic RAST, without affecting specificity. However, this system is still semi-automatic and requires daily calibration. UNICAP 100 is a completely automatic autoanalyser for total IgE, specific IgE and Eosinophil Cationic Protein, which combines the high sensitivity of the CAP system with complete automation and monthly calibration. The aim of the present study is to assess the practicality and reliability of UNICAP 100, when compared to the CAP System, for the determination of total IgE and specific IgE, as well as the sensitivity and diagnostic specificity; using as a reference skin tests in 150 paediatric patients. The coefficients of variation in the study of intraseries imprecision ranged between 2.1% and 3.6% for total IgE and between 2.2% and 5.1% for specific IgE, depending on the allergen and the level studied. The intraseries imprecision ranged between 3.3% and 7.7% for total IgE and between 5.2% and 8.9% for specific IgE. The coefficients of correlation of the study of interchangeability with the results of the CAP System varied between 0.985 and 0.998, all the allergens tested (9) being interchangeable. Finally, the diagnostic sensitivity varied between 70% and 95% and the specificity between 87% and 100%. In conclusion, UNICAP 100 showed results that were interchangeable with the CAP System, noticeably improving the benefits owing to its complete automation and its calibration system.

[Perennial rhinitis: antihistaminic and anti-inflammatory treatment]. / Rinitis perenne: tratamiento antihistamínico y antiinflamatorio.

The use of various medications in chronic rhinitis in children is discussed. Evastin has been shown to eliminate histamine papules in 93% of cases and those caused by D. pteronyssinus in 68% of cases. After 10 days of treatment, conjunctival response decreased or disappeared in 80% of cases and nasal response decreased in 69%. Clinically, evastin was effective in 14 of 22 children and produced moderate effects in 2 and no effect in 6. There were no dropouts because of problems of tolerance. In a preliminary study of intranasal azelastin in 21 children with chronic allergic rhinitis, clinical improvement was significant. Various multicenter trials are reported, focusing on those using fluid budesonide. Both medications were effective in reducing symptoms and the antihistamine effect usually was earlier. There were no differences between medications as evaluated by nasal challenge or tolerance. Finally, budesonide was used in 13 patients for 4 months. Nasal obstruction and secretion improved, and rhinomanometry results improved significantly.

[Ebastine : treatment of perennial rhinitis in the child]. / Ebastine, traitement de la rhinite persistante chez l'enfant.

Ebastine is H1 receptor antagonist, powerful and selective for histamine. Its efficacy has been evaluated in control of symptoms of persistent rhinitis, appearance of secondary effects and tolerance of the drug, in 30 children who were suffering from persistent rhinitis, of which the diagnosis included:- clinical history, skin tests (prick test) nasal and conjunctival provocation tests, total and specific IgE. All the children had treatment for 30 days. The parameters followed were:- clinical score, skin tests, nasal and conjunctival provocations and evaluation of secondary effects, of the start and 10 days after the end of treatment. The results obtained were a disappearance or reduction of the weals from histamine and specific antigens, disappearance or reduction of the response in nasal and conjunctival provocation with carbachol or specific antigens, clear clinical improvement in 22 patients, in 2 small improvement and no response in 6 patients. We conclude that Ebastine improved the clinical symptoms in persistent rhinitis, the skin test is inhibited and sensitivity of the shock organ is reduced. No secondary effects were seen on the Central Nervous System (SNC) and the tolerance of the drug was very good.

Effect of conditions in obtaining blood samples for ECP testing in children.

Eosinophil Cationic Protein (ECP) is a basic protein found in eosinophil granules. This cell and its mediators are currently considered to be potential indicators of the severity of inflammation in the organism. ECP concentration can be reliably tested using several RIA or ELISA methods. It is well known that the conditions of sample obtention can affect the ECP values in blood. The aim of this study is to establish which parameters affect ECP testing during regular blood sample collection and how they affect it. Blood samples taken for the routine study of five children attended in our department were analysed: four were asthmatic and one child had atopic dermatitis. In the results we observed that ECP was not detected in the blood samples taken with EDTA tripotassium. In both the plasma samples taken with heparin as well as with serum, more ECP was released at a higher temperature. In the release of ECP obtained by coagulation, samples at 37 degrees showed values of between 4 and 20 higher than those obtained for an hour at 0 degrees. There is a considerable variability in the testing of ECP depending on the blood test extraction conditions, the range is bigger in the samples with eosinophils. These results imply the need to define a stricter protocol for obtaining samples than that suggested at present.

[Do nasal and conjunctival provocation tests represent a trustworthy parameter for the follow-up of childhood IgE-dependent bronchial asthma?]. / Est-ce que les tests de provocation nasale et conjonctivale représentent un paramètre fiable dans le suivi de l'asthme bronchique infantile IgE-dépendant?

The aim of this study is the evaluation of the response at the level of different organs (nose and conjunctiva) of desensitizing treatment in children suffering from bronchial asthma and receiving immunotherapy with D. pteronyssinus.

Specific IgE determination using the CAP system: comparative evaluation with RAST.

The CAP system's main contribution is its solid phase, which consists of a cellulose polymer activated within a capsule (the ImmunoCAP). This solid phase can bind more protein to it, and, in addition, the conditions of reaction seem to make the system more sensitive at detecting antibodies to certain antigens. It is therefore important to assess the new analytical and diagnostic performance in comparison with previous systems. In this context, we studied the reliability and comparison with the RAST and with skin tests carried out on 144 pediatric patients. Skin tests and specific IgE for radioimmunological RAST (radio-allergosorbent test) and for the fluoroimmunological CAP system were performed on all the patients. The RAST/CAP correlation quotients for the different allergens tested varied between 0.971 and 0.991. Diagnostic sensitivity increased for all the allergens studied and specificity remained unchanged. The system provides reliable results, with better diagnostic capacity than RAST, but it must be quantified for each allergen because its results are not interchangeable.

Budesonide: treatment of bronchial asthma during childhood.

Nowadays inhaled corticosteroids are the first step in treating inflammation of the airways. It is evident that these drugs are not free of side effects; however, the fact that at present the most commonly used method is by inhalation and that these drugs undergo metabolic changes in the lung, makes them safe in that a part of the side effects, which are observed when they are administered systemically, disappear. Budesonide was one of the last corticosteroids for topical application to appear on the market and its powerful anti-inflammatory action together with in versatility (it can come in aerosol form using MDI or in solution for nebulizers as well as in dry powder) make it possible to use during all stages of a child's development. In 75 children treated with Budesonide over a long period (18-24 months) we were able to evaluate the drug's clinical efficacy in the reduction in number and intensity of attacks registered together with their accompanying symptoms. Significantly (p < 0.001) it were able to restrict the bronchodilatory medication needed to control their asthma. Similarly, we were able to verify that the FEV1 was normalized and that the Peack Flow was stabilized. We were not able to find any interruption in the hypothalamo-hypophysio-suprarenal axis and the weight-height curves continued to evolve chronologically. With regards to the side effects, three cases of colonization candidiasis were recorded through there were no clinical repercussions and treatment did not need to be suspended.

The prick test and specific IgE (RAST and MAST-CLA) compared with the oral challenge test with milk, eggs and nuts.

In spite of the development of numerous in vivo and in vitro diagnostic techniques for food allergy, the oral challenge test (OCT) is still the "gold standard". Consequently, we have compared it with some of the more recent techniques. We studied 36 patients with a medical history compatible with food allergy (to milk, eggs or nuts) and 11 patients without food allergy (6 nonatopic and 5 with acarid allergy). A prick test, specific IgE (RAST and MAST-CLA) and an OCT with the suspected food were performed in all patients. The following parameters were calculated for all patients overall and for each of the three allergic groups separately: sensitivity, specificity and match with the OCT. We also studied the RAST-MAST-CLA correlation and the variability of the MAST-CLA. The prick test was the most sensitive (95%) and the MAST-CLA (13% divergence in two measurements) the most specific (92%). The RAST and the MAST-CLA (68% match) gave similar results, with an acceptable match (75% and 77%, respectively) with the OCT. The medical history could only suggest the diagnosis (39% false-positives). After comparing the results with those in the literature, it is suggested that greater attention should be paid to the limitations of these techniques compared with the OCT.

The value of specific IgG4 determination in childhood allergy to egg in relation to specific IgE and the provocation test.

The value of IgG4 determination in food allergy shows conflicting results in the medical literature. Our pediatric study was carried out in two phases. The first compared the percentage of detection and agreement of specific IgE (RAST) and IgG4 (FAST) for egg white and egg yolk in 104 patients with possible hypersensitivity to egg and positive skin tests. The second, in 22 new patients, compared IgG4 determination with the oral provocation test (OPT; the diagnostic "gold standard"). In the first phase, the percentage of positive cases for both antibodies was almost identical, but little agreement was observed between them. In the second phase, the sensitivity, specificity and agreement with the OPT were higher for IgE than for IgG4. Thus, we conclude that IgG4 levels may be high in food allergy, but their detection seems to have little diagnostic value in allergy to egg proteins in children.

Prevention of exercise-induced asthma in children using low doses of inhaled furosemide.

It has been demonstrated that inhaled furosemide inhibits indirect but not direct bronchoconstricting stimuli. The exercise test (ET; indirect) has been shown to be inhibited in adults. Our aim was to determine whether the ET was also inhibited in children by low doses of furosemide. We studied 10 asthmatic patients with a mean age of 11.1 years whose ET results were positive, and in whom the ET was repeated after inhaling 28 mg of furosemide. After 10 min, there were no significant signs of bronchodilatation. The percent decrease in mean FVC, FEV1, MF50 and peak flow (PF) was significantly lower with the premedication. The protection achieved was: FVC, 66.5%; FEV1, 51.4%; MF50, 30.3%; and PF, 63.9%. No clinical response was observed in 5 of 10 cases. It was concluded that 28 mg of inhaled furosemide inhibits the ET in asthmatic children.

Study of the sensitization to storage mites in a pediatric population in Barcelona.

We performed the following study in order to determine the prevalence and characteristics of sensitization to storage mites in children mostly from the city of Barcelona. All children over 3 years of age attending our unit for the first time due to respiratory problems were given cutaneous tests using the prick test for the house dust mites Dermatophagoides pteronyssinus and D. farinae, and the storage mites Acarus siro, Lepidoglyphus destructor and Tyrophagus putrescentiae. We carried out a RAST and conjunctival test when it was considered appropriate. Of a total of 356 children studied, 39 showed cutaneous sensitization to storage mites, which represented 11% of the population studied, and 20% of the total sensitized to mites. However, only 3 of these children were only sensitized to storage mites, the remaining 36 (92%) also showing sensitization to house dust mites. Of the storage mites studied, L. destructor was the most significant. A history of immunotherapy to mites was associated with a greater percentage of positive cutaneous tests to storage mites, although this was not the case with the RAST test.

Alternative milk formulas in allergies to proteins in cow's milk.

A variety of "hypoallergenic" formulas have appeared on the market over the last few years for feeding lactating infants prone to a high atopic risk of allergy to cow's milk. These formulas consist of soya preparations, hydrolyzed proteins and so-called basic formulas. This paper describes the main characteristics of such formulas, with particular emphasis on their tolerance, indications, related immunological aspects and antigenic capabilities. Notifications of anaphylactoid reactions with hydrolyzed proteins and the possibility of interactions with the IgE antibodies in cow's milk indicate such formulas in cases of non-IgE-mediated intolerance. Although soya preparations may be allergenic, they do not present interactions with the proteins in cow's milk; thus, they are particularly indicated in children with protein allergy to cow's milk with specific IgE antibodies.

Specific IgE antibodies in nasal secretions: correlation with serum values and clinical tests.

The presence of specific IgE in external secretions and the possibility of quantifying it has aroused the interest of many research workers. Nevertheless, there is still disagreement with regard to how useful this practice is from a clinical point of view. We have compared the presence of Dermatophagoides pteronyssinus (Dp) specific-IgE in the nasal secretion of 17 patients suffering from rhinitis with the results of prick tests and nasal and/or conjunctival challenge tests. As a preliminary step we have updated techniques and made a correlation between the parameters mentioned. The results for total IgE (n = 17) show a correlation coefficient (r = .39, NS) between serum values (251 +/- 239) U/L and those obtained in nasal secretion (28 +/- 36) U/L. (2) Serum and nasal-Dp-specific-IgE values (13 +/- 15 and 5 +/- 9, respectively: (r = .72, P = .0011) match in 14 of the 17 determinations. In two of them, the serum values of Dp-specific-IgE, but not the nasal ones, match the in vivo tests. In the others, it is the nasal secretion determination that matches the in vivo tests while the serum and nasal determinations match (82%). These results match in 86% of cases with prick tests and in 93% with nasal/conjunctival challenge tests.(ABSTRACT TRUNCATED AT 250 WORDS)

Mustard allergy. Two anaphylactic reactions to ingestion of mustard sauce.

Two cases of anaphylactic reactions set off by the ingestion of a small amount of mustard sauce are described. Mediation by specific IgE to mustard was determined by skin prick tests and radioimmunoassay, which suggested a type I hypersensitivity mechanism. Despite the antigenic potency of mustard, a spice that is consumed frequently, very few cases of hypersensitivity from ingestion have been described.

Allergy to pomegranate (Punica granatum).

We present the case of a 7-year-old IgE-dependent asthmatic child who, moments after ingesting several pomegranate seeds, showed a clinical condition of bronchospasm which responded to treatment with inhaled salbutamol. Cutaneous tests using the prick-by-prick techniques with extract of the fresh fruit were positive and the RAST for pomegranate was 0.8 PRU/ml. In the literature studied, we have found few specific references to allergy to pomegranate.