allergyToday parents increasingly face such a problem as children’s allergies: over the last 25 years the number of allergic children has increased twice or, according to some estimates, even three times. That’s why Canadian Health&Care Mall advices paying a special attention to this problem.

Theoretically, any substance which structure differs from human tissue structure, that is, any substance brought in from the outside, can elicit an immune response. But normally the body must not be mistaken, separating agents for harmful and harmless. Allergy is an abnormal reaction of the body to a substance considering it dangerous, though it is not.

A bit of science

There are two concepts that are often confused: allergy and pseudo-allergy.

The difference between them is principled, it lies in the nature of the immune response mechanism. But we are not going “into the jungle”. Let’s say that a true allergy is a hereditary disease; if one of the parents suffers from an allergy, the child will have the same allergy with a chance of 30%; if both parents suffer frmo an allergy, the child will be allergic with a probability up to 60%.

Pseudoallergy is a group of reactions, different in origin, most of which are somehow related by excess histamine in the body or its general intoxication. But the immune system is not originally involved in these reactions developing process. Specific causes of children’s allergies in this case may be different: a violation of the mechanisms of development and binding histamine or its excess amount brought in with food. For example, a large amount of this hormone is found in seafood, and chocolate promotes the production of histamine in the body.

Types of children’s allergies

allergyFood allergy is the most common. Allergic reactions may be caused practically by any food product, especially if it contains a large amount of histamine or substances providing a deleterious effect to the body (at a high concentration), such as dyes, preservatives, stabilizers, flavors. Children under two years old often suffer from them against a background of dysbiosis or too early feeding. In most cases, the allergic reation is caused by cow milk, egg white, fish, some kinds of fruit and vegetables.

Allergic to animals is also quite frequent. But in fact it is not quite what it seems to be. It is not an allergy to hair, as people usually say, but one of the animal waste products: saliva, serum, epithelium, urine or feces.

Allergies to pollen usually occur after 8 years old. The period of the first symptoms may help define a group of “suspected” plants: from April to May – the period of flowering trees, from June to July – meadow grasses, from August to September – weeds.

Children’s allergy to drugs is often caused by penicillin and its derivatives, but may also occur in response to practically any group of drugs. Drug allergies can cause anaphylactic shock, so it is extremely dangerous.

Allergy to house dust is exaggerated reaction to the release of small mites living in our home in large quantities. Even a daily general cleaning of the house won’t get rid us from them completely.

Allergy to insect stings (usually bees or wasps) is hypersensitivity to the venom of stinging insects.

Allergy to cold is not an allergy in its essence: the response to the sudden drop in temperature, which is manifested in the form of a rash and redness, similar to hives, ramaining even few hours after exposure to cold.

Helminth intoxication also often leads to pseudoallergic reactions. In case of allergy symptoms, check the child for the presence of worms. (more…)

bronchial asthma and allergyAllergy is a sharp reaction of the body’s immune system to usually harmless substances. Symptoms of allergy can occur in different parts of the body, lasting from a few minutes to several days and be different in severity. Let’s learn about the disease nature and treatment methods together with Canadian Health&Care Mall.

There may be allergy for hair of some animal species, a variety of products, dust, medicines, chemicals, insect bites and pollen. Substances that cause an allergy, are called allergens. In some cases, allergic reactions are so weak that you can not even be aware that you generally suffer from allergies.

But allergies can bу also extremely dangerous and even life threatening. People suffering from allergies, may get anaphylactic shock – a severe pathological condition associated with an extremely sharp reaction to the allergen. Anaphylaxis can be caused by various allergens: drugs, insect bites, food. Also, anaphylactic shock can happen due to skin contact with an allergen, such as latex.

A food allergy is an immune reaction caused by certain foods and accompanied by well-known symptoms. A food allergy occurs when the body mistakenly take a certain product for a threat to the body and makes the immune system produce antibodies for self-defense. In case of readmission of the allergen, the immune system quickly “learns” this material and reacts immediately by producing antibodies again. These substances cause allergic symptoms. Food allergy often develops in this way.

In some cases, adults get rid of allergies observed in childhood. But if the allergy manifested itself only in adulthood, it’s very difficult get rid of it. Allergic rhinitis is observed in 1 case of 10 and is often hereditary. People with other allergic diseases, such as asthma or eczema also often suffer from allergic rhinitis. Such allergies are more common for women than for men. In case of allergic rhinitis we may observe following symptoms: itchy eyes, throat, nose and on the palate, sneezing, and stuffy nose, watery eyes, mucous discharge from the nose, conjunctivitis (redness and pain in the eyes). In severe cases of allergic rhinitis there may happen an asthma attack (especially people suffering from asthma) and / or eczema.

Causes of allergies

petsSome people’s immune system reacts sharply to certain substances (allergens), producing a variety of chemicals. One of them, histamine, causes allergic symptoms. The reaction of the body can occur through inhalation, skin contact, administration of allergen or receiving it in food. Animal hair, fluff, dust, foods, cosmetics, medicines, pollen, cigarette smoke are the most popular allergens. (more…)

Bronchoalveolar lavageBronchoalveolar lavage (BAL) was used in these studies to examine the local effects of inhalational antigen challenge on lung lavage cell populations and to determine the safety of BAL in this setting in mild asthmatic patients. For safety reasons, the timing of BAL in these studies was designed to purposefully avoid the peak airway responses to antigen challenge. We found, using strict selection criteria for subjects with bronchial asthma, that BAL performed after allergen BPC is feasible and can be a safe technique to evaluate local airway responses to antigen challenge. The BAL combined with BPC did not affect the occurrence of an early or late asthmatic response, and no fall in FEVi was induced by the lavage procedure itself.

Rankin and co-workers also found no significant decrease in FEV1 in mild asthmatic subjects undergoing BAL; however, the patients in this study were not exposed to an aerosol challenge with allergen. De-Monchy and co-workers also lavaged mild asthmatic subjects after exposure to aerosolized allergen. Although there did not appear to be any complications in this study, pulmonary function tests were not performed after the lavage to document the safety of this procedure after experimental exposure to antigen. The present studies also support the recent guidelines that were established for these types of studies by the American College of Chest Physicians, the American Academy of Allergy and Immunology, the American Thoracic Society, the National Heart, Lung and Blood Institute, and the National Institutes of Allergy and Infectious Diseases.

Prior studies by DeMonchy et alu showed that there were increased eosinophils but no neutrophils in lavage fluid of asthmatic patients after an aerosol challenge; however, no baseline studies were performed on these patients. In this regard, Godard et al showed that eosinophils were increased, at baseline, in asthmatic subjects. The present study shows that eosinophils are increased at baseline in lavage fluid of asthmatic patients and increased further with aerosol exposure to allergen. The increased numbers of neutrophils at four but not 24 hours in the present study may be explained by the fact that lavage was performed at earlier time points in the present study compared to the study by DeMonchy et al. These observations suggest that both neutrophils and eosinophils migrate into the airways within four hours of allergen challenge and are consistent with prior studies which showed an influx of neutrophils, especially at six hours, in late phase responses in the skin. In addition, both neutrophil chemotactic activity (NCA) and eosinophil chemotactic activity (ECA) have been demonstrated in peripheral blood during early and late phase responses which suggest that these cells may migrate into the airways in response to these inflammatory mediators. The present studies in asthmatic patients are also consistent with the studies of Marsh et al who showed an increase of neutrophils and eosinophils after antigen challenge in an animal model of asthma.


asthmaPatient Population

The characteristics of the patients with asthma are shown in Table 1. All but one of the asthmatic subjects who were experimentally challenged and lavaged responded to BPC with both an early and late phase airway response; one had a late response only. Four of 12 asthmatic patients had dual skin responses. The five normal subjects were challenged with five breaths of 10,000 PNU/ml concentration of Altemaria without response. ‘In season” asthmatic subjects were experiencing mildly symptomatic asthma but were receiving no medication at the time of BAL.


We observed no complications during the bronchoalveolar lavages. There was an increased tendency for asthmatics to cough; however, coughing was never severe enough to prevent wedging of the bronchoscope. Ear oximetry measurements of arterial oxygen saturation during lavage were always above 94 percent. There were no ECG abnormalities.

Pulmonary Function Measurements

Pulmonary function measurements performed just prior to bronchoalveolar lavage were near the predicted normal baseline for all subjects except two (patients 3 and 9) who were occasionally mildly symptomatic during seasonal exposure. At the time of BAL, their FEVX was 60 and 65 percent of predicted, but their chests were clear of wheezes before BAL. An average decrease in FEVi of 13 percent below baseline values was measured just before BAL and following BPC for the entire group. There was no significant decrease in the FEVj of patients with asthma after lavage compared to their prelavage FEVi (Fig 1). One patient, however, (No. 9) had a 32 percent decrease in FEVj after BPC and lavage. Wheezes were heard in the area of lavage, but cleared with local epinephrine (1:10,000) to the carina. The other patient (No. 3) inadvertently did not have a postlavage FEVj measured but was asymptomatic without wheezing after lavage.

In the asthmatic subjects who were lavaged <4 hours after BPC, there was a similar maximal decrease in FEV1 during the early and late asthmatic response regardless of whether BAL was being performed (Fig 1). Four of five asthmatic subjects who were lavaged 24 hours after BPC had dual responses, but these responses were unaffected by BAL.


inhalationInhalation of specific allergens usually results in increased airways resistance in asthmatic subjects. This reversible airway obstruction is associated with release of mast cell mediators and an inflammatory response in the airways. In the present studies, we used bronchoalveolar lavage (BAL) to directly assess local inflammatory changes occurring within the airways of atopic asthmatic subjects undergoing experimental bronchoprovocation (BPC), or during environmental, ie, “spontaneous” seasonal exposure. We also examined changes in local cell populations and evaluated lung eosinophils and mast cells morphologically for evidence of degranulation.


Subject Selection

Seventeen subjects volunteered for these studies. Twelve had mild allergic asthma and five were asymptomatic normal individuals. All subjects gave informed consent to undergo BAL and aeroallergen BPC before entering this study which had been approved by the Human Subjects Use Committee of the University of Iowa. These studies also strictly conform to the guidelines set forth by the American College of Chest Physicians, American Academy of Allergy and Immunology –, American Thoracic Society, the National Heart, Lung and Blood Institute, and the National Institutes of Allergy and Infectious Diseases. In order to evaluate each individuals atopic status, a complete medical history and physical examination were performed, and a routine battery of allergen skin tests was applied intradermally to the triceps area of the upper arm. A wheal 5×5 mm or greater than diluent control was considered positive. Specific allergens used for BPC were titered on the forearm and observed at 30 minutes and six hours. Histamine and codeine positive control substances were also applied. The atopic asthmatic individuals gave a history of mild seasonal asthma, were skin reactive to the appropriate allergen, developed bronchoconstriction in response to inhaled specific allergen, and demonstrated a positive methacholine aerosol challenge (Table 1). Normal control subjects had no symptoms of respiratory allergy treated by Canadian Health&Care Mall, negative skin tests, a negative methacholine challenge, and no immediate family history for allergic disease.

Criteria for Asthmatic Subjects Undergoing BAL

In order to reduce the risk of triggering already hyperresponsive airways and to maintain rigorous control of those who would be challenged and lavaged, we established specific criteria for all asthmatic subjects (Table 2). Subjects were between the ages of 18 and 45, nonsmokers, and had BALonly mildly symptomatic seasonal asthma. Immediately prior to BAL, they were required to have an FEV1.

Aerosol Challenges

A methacholine (Meth) aerosol challenge was employed to document hyperresponsive or normally responsive airways. Using established procedures, we employed the Johns Hopkins Dosimeter and concentrations of Meth from 0.075 to 25 mg/ml. Subjects were given five breaths of each concentration of Meth by taking slow deep breaths from functional residual capacity to total lung capacity, without breath-holding. A drop in FEVt by 20 percent (below diluent baseline) which persisted for at least five minutes was considered a positive response. The provocative dose producing a 20 percent decrease in FEVj (PDM [FEVJ) was calculated, and expressed as breath units (BU).

Allergen inhalation was performed in a similar manner, using increasing five-fold concentrations of allergens from 1 protein nitrogen unit (PNU)/ml to 10,000 PNU/ml. A 20 percent or greater drop in FEV1 which persisted ^5 minutes was considered positive, and the challenge was stopped. Those subjects who responded to allergen challenge were closely observed in the Clinical Research Center (CRC) of the University of Iowa for 24 hours. Pulmonary function tests were obtained (every 15 minutes for 60 minutes and then every hour from a total of 24 hours) using a forced expiratory maneuver with the Jones Pulmonor II (FVC, FEV^ and MEFR^ts). Normal individuals as control subjects were also challenged with allergen, observed in the CRC overnight, and pulmonary functions were similarly obtained.

Atopic symptomatic (in season) asthmatic subjects who were not taking any medications were challenged out of the appropriate historical season with an allergen to which they were clinically sensitive. Altemaria was used primarily, but cat dander extract was inhaled by one subject, short ragweed extract by another, and house dust by a third. Normal subject control subjects were challenged with 10,000 PNU/ml Altemaria. The PD* for the airway response following allergen challenge was calculated using previously described methods.

BAL Following BPC

For safety reasons, in most instances, we wished to lavage patients when the FEVt was near baseline value. For this reason, we chose time periods two to four hours or 24 hours after BPC for BAL (all asthmatic patients had late phase responses which occurred at 4 to 24 hours after inhalation of allergen). Each subject was prepared for BAL in a manner which is routine for all bronchoscopies, including bronchoalveolar lavage, at the University of Iowa. Atropine sulphate, 0.6 mg IM, and morphine sulphate, 8 mg IM, were given one half hour before the procedure. Xylocaine (4 percent) was aerosolized into the upper airways and applied topically to the pryriform sinuses to prevent coughing and to effect local anesthesia. Each individual also inhaled two puffs (0.65 mg/puff) of bronchoscopemetaproterenol 15 minutes prior to bronchoscopy. All patients and control subjects were medicated identically. Bronchoscopy was performed using a fiberoptic bronchoscope; the tip of the bronchoscope was wedged into three different subsegmental bronchi in the left upper lobe, left lower lobe, and right lower lobe for lavage. Lavage in each site was performed by injecting five 20-ml aliquots of warmed (37°C) normal saline solution (total = 100 ml). Immediately after the injection of each aliquot, suction was applied and the fluid recovered in a sterile trap. The volume of each lavage specimen was measured and then immediately transported to the laboratory.