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Jaritzy Negrín González

Cow´s milk allergy

Cow´s milk allergy 1024 576 Jaritzy Negrín González

Cow’s milk is the food that most frequently causes food allergies in children under 1 year of age.

Why is food allergy more common?

Because cow’s milk proteins are one of the first antigens (allergens) that the child comes into contact with in their diet.

How is cow’s milk composed?

Cow’s milk is composed of proteins that are classified into two groups: casein (80%) and whey proteins (20%). The main components of whey proteins are betalactoglobulins and alphalactalbumin.

These proteins are the allergens that trigger the production of antibodies.

Why is it called cow’s milk protein allergy?

These are clinical signs of an adverse reaction to cow’s milk with a proven immunological mechanism: reactions mediated by IgE antibodies or by another immunological mechanism (non-IgE). It is important to differentiate between both types because they present different pathophysiology, symptoms and evolution.

When do symptoms start?

It is variable, it can start during the period of exclusive breastfeeding but most cases begin when starting artificial breastfeeding after the period of breastfeeding. It begins in the vast majority of cases the first year of life with a maximum peak between 3-4 months of age. Exceptionally they can start after the second year of life.

What are the symptoms?

In 75-92% of children with cow’s milk protein allergy may have more than one symptom:

  1. Skin symptoms: this is the most common clinical condition characterized by erythema (redness), urticaria (wheal-like lesions) and angioedema (swelling). Initially it may appear in the perioral area and may or may not generalize to other parts of the body. Sometimes infants may have as their first and only clinical manifestation the refusal of cow’s milk bottle feedings or breastfeeding.
  2. Digestive symptoms: may be vomiting and diarrhea. In 30% of cases they are associated with other symptoms. Vomiting is a common clinical manifestation in IgE-mediated allergy.
  3. Respiratory symptoms: wheezing, cough, rhinoconjunctivitis are rare as an isolated symptom in the infant.
  4. Anaphylaxis: may be the debut in infants in 1% of cases. It is common in older children or adolescents with persistent cow’s milk allergy after accidental contact or transgression.

How is the allergy study carried out?

Allergy tests are indicated by making a personalized evaluation of each patient according to their clinical picture.

Initially in the consultation with your allergy specialist, a medical history is taken, detailed anamnesis of what happened is elaborated: type of symptoms, time of onset from ingestion of the food, if it is the first time it happens and it was referred spontaneously or with medication and of what type.

Subsequently, it is decided whether it is necessary to perform skin tests (prick tests) and blood tests to determine specific IgE for cow’s milk proteins.

According to the results, the performance of a controlled oral challenge test with cow’s milk will be assessed. This test consists of eating the food in progressive amounts under the supervision of an allergy specialist. Its goal is to confirm or rule out cow’s milk protein allergy. If the test result is positive, there is an allergy, it allows to know the threshold dose with which the patient presents symptoms when eating the food, avoiding unnecessary or very restrictive diets.

How is the evolution and prognosis of cow’s milk allergy?

Cow’s milk protein allergy tends to evolve into spontaneous remission in the short to medium term.

Clinical food tolerance is favorable in most infants and young children with IgE-mediated allergies. From 4 years of age, spontaneous tolerance is less likely. It is estimated that from 6-7 years of age cow’s milk protein allergy persists in 10%.

What is the treatment for cow’s milk allergy?

After the evaluating and diagnosing cow’s milk allergy, the elimination diet is the initial treatment of choice. This diet consists of the elimination of all cow’s milk proteins and foods that contain them. Cow’s milk can be replaced by hydrolyzed, elemental, soy or rice formulas.

For persistent cases that do not reach spontaneous tolerance, there is “Oral Immunotherapy” treatment, which consists of the progressive intake of food according to protocols and always supervised by an allergy specialist. Due to the risk involved, “oral immunotherapy” should be performed in the hospitall. The purpose of this treatment is to modify the allergic response by making the patient desensitized or tolerant to cow’s milk.

Remember to request the assessment of your allergy specialist if you suspect cow’s milk allergy, from ClinicAL we hope to have provided information about this allergy so frequent in the pediatric age.

Dra. Jaritzy Negrín González
Allergy Specialist

Plane tree pollen allergy

Plane tree pollen allergy 1920 1080 Jaritzy Negrín González

What is the plane tree?

It is a leafy tree belonging to the Platanaceae family, known as shade plane tree (Platanus hispanica), also called Platanus hybrida or Platanus acerifolia.
In Spain it is considered an urban tree. It has been cultivated in groups or lined up along promenades and avenues. It can reach heights above 30 meters. It has a fast growth and tolerates polluted atmospheres such as those of some Spanish cities. It is estimated that under suitable conditions it can live up to 300 years.

Alergia a polen de platanero

How is it constituted?

It has large leaves, wider than long, arranged alternately, with 3-5 lobes. It has a hard, light, resistant and fine-grained wood that can be used in cabinetmaking and veneer. Its male and female flowers are on the same tree in a grouped way and hang on long peduncles. The fruit is a wedge-shaped achene grouped radially in spherical infrutescences as balls.

What is its use?

Its main use is ornamental, as a shade tree. During the last decades it is possibly the most introduced tree species in the alignments of towns and cities. This is due to its rapid growth, wide and dense crown, and low acquisition cost.
The plane tree is found in many Spanish cities being Barcelona and Madrid where their number is significantly higher. This is because in both cities it has been imposed as an alignment tree. The greater number of plane trees in these cities are directly related to the increase in allergic symptoms due to their pollination.

When does it pollinate?

The pollination of the plane tree is explosive at the beginning of spring, from March to May according to the latitude, climate and weather conditions of each city. In Barcelona, especially the second half of March and the first half of April.
A tree can release 143 billion grains of pollen. In 2013, in Barcelona, there was a high concentration of banana pollens reaching levels of 48,626 grains/m3 of air (data from the Aerobiology Committee of the Spanish Society of Allergology).

Has climate change affected their pollination?

The increase in global temperature due to climate change and the decrease in average temperature in the winter months is producing a delay in the onset of pollination and therefore a delay in completion, without modifying its pollination period.

What symptoms may you have?

The clinical symptoms associated with plane tree pollinosis are rhinoconjunctivitis and seasonal asthma that begins abruptly a few days after pollination begins.
The pollen level from which it is considered capable of producing symptoms in sensitized people is 130 grains/m3 of air.

Alergia polen platanero sintomas

If you are allergic to plane tree pollen, can you have food allergies?

Yes, but it doesn’t happen to everyone.
Patients with allergy to plane tree pollen may have food allergy to fruits (peach, apple, kiwi, melon), nuts (hazelnut, peanut) and vegetables (lettuce, green beans) among others; probably related to sensitization to LTP (Lipid transfer protein) which is a common allergen of plane trees and such foods.

Remember to request the assessment of your allergist if you present symptoms at the beginning of spring, from CliniCAL we hope to have provided information about plane tree pollen allergy.

Dra. Jaritzy Negrín González
Allergy Specialist

Pet Allergy

Pet Allergy 1920 1280 Jaritzy Negrín González

Cats and dogs are pets that frequently cause allergies, they can produce:

1. respiratory symptoms such as sneezing, itchy nose, runny nose, shortness of breath or wheezing (rhinitis or asthma).

2. ocular symptoms such as redness, itching and tearing (conjunctivitis), and

3. skin symptoms as itching and redness (pruritus and erythema).

All animals with hair or feathers can cause allergies: cats, dogs, guinea pigs, hamsters, rabbits, horses, rats, mice, cows, birds, or even scaled animals such as reptiles.

The prevalence of allergy to exotic animals has increased in recent years, for example: rodents (mouse, guinea pig and gerbils) mammals (ferrets and monkeys) reptiles (snakes and iguanas) exotic birds (parrot and cockatoos).

Where are allergens found in animals?

Animal allergens are found in: dander, saliva, urine, hair or feathers. Dandruff is the desquamated epithelium of animals, it constantly detaches and remains floating in the air, while hair tends to fall, which is why it is more common to find it on the floor or on the surfaces of furniture (sofa, shelves, bed). , etc.). It is for this reason that the main cause of animal allergy symptoms is the dander that is floating in the environment where the pet resides, rather than the hair itself. The short-haired or hairless animal is falsely considered “non-allergenic.”

The removal of the animal is not a short-term solution, the allergen (especially dander or hair) can persist in the home for weeks or months. It is for this reason that people allergic to animals can present symptoms when they are in environments where pets live, even if they are not present at that time.

Who may have an allergy to animals?

Sensitization to animals occurs through continuous exposure living with the pet, but also in professionals such as veterinarians or people who work in research with animals.

Is there treatment?

Yes, the first thing we advise is the avoidance of the allergenic source, that is, contact with the animal. There are also treatments such as specific immunotherapy (allergy shot) to cats, dogs and horses.

If you have any respiratory, ocular or skin symptoms when you are in contact with an animal you should go to your Allergy Specialist to carry out the pertinent study and assess which is the best treatment to control your symptoms or if you can benefit from an “allergy shot”.

Allergy to cats

Within the allergy to pets is one of the most frequent. Symptoms can be nasal (rhinitis), bronchial (asthma), ocular (conjunctivitis), cutaneous (itching) or coexist several symptoms at once. The onset of symptoms can occur due to direct (and close) contact with the pet, such as living in the same home or exposure to an environment where pets reside. In this case, if sensitization is high (“very allergic”) symptoms may occur within minutes, even if the pet is notpresent. Symptoms can also be caused by indirect contact, such as contact with clothing that can carry allergens (dandruff, hair or secretions). This is very common in winter and shared work environments or classrooms where warm clothes carry dandruff or hair and thus expose other colleagues to these allergens.

Up to 8 allergens have been identified in the cat, the most important and majority is Fel d1. This allergen is excreted by the sebaceous glands and accumulates in the skin and dandruff. It can be found in smaller amounts in saliva, lacrimal and perianal glands. Male cats have higher levels of Fel d1 than females.

Allergy to dogs

Like the cat, dog allergy is a common allergy. 6 allergens have been identified, which are found in dandruff, urine and saliva, the majority being Can f1 and Can f5. Male dogs have more Can f5 than females. As a curiosity this allergen presents cross-reactivity with the human prostate antigen, so it has been involved as a cause of allergy to human semen in sexual relations of women previously sensitized to dog.

To this day there is not enough data to apply the name “hypoallergenic” to any breed of dog.

Any doubs?

Contact with us!

Dra. Jaritzy Negrín González
Allergy Specialist

Allergic asthma

Allergic asthma 1920 1280 Jaritzy Negrín González

Bronchial asthma is a chronic inflammatory disease of the airways that causes variable airflow obstruction.

How does inflammation occur?

Once we inhale the allergen (dust mites, pollen, animal dander, etc.) and it comes into contact with the bronchial mucosa, a process begins in which different cells and inflammatory mediators intervene. Genetic factors have also been shown to influence the inflammatory process.

If the bronchial mucosa becomes inflamed, the diameter of the airway decreases and symptoms occur.

What are the symptoms?

-Shortness of breath (dyspnea).


-Tightness in the chest.


Each person manifests these symptoms with varying frequency and intensity, depending on the causal allergen. For example, a person with allergic asthma caused by the pollen of “plátano de sombra” will have symptoms only at the time of pollination, approximately 2-3 weeks between the months of March and April; while a person who has allergic asthma from cats and lives with a cat will have symptoms continuously on a daily basis because of constant exposure.

Is there a treatment?

Yes, bronchial inhalers are indicated to treat inflammation, including inhaled corticosteroids, inhaled corticosteroids in combination with long-acting B2 agonists, short-acting B2 agonists and oral corticosteroids, among others. It all depends on the severity of each case.

Another treatment available is specific immunotherapy (“allergy shots”), once an allergological study has been carried out to determine the cause of the allergic asthma.

It is also important, if possible, to avoid the causative allergen.

What can you do if you have these symptoms?

We recommend that you see an allergy specialist for medical evaluation and testing as appropriate.

¿Any doubts?

Dra Jaritzy Negrín González
Allergy Specialist

Allergic contact dermatitis due to nickel

Allergic contact dermatitis due to nickel 1920 1280 Jaritzy Negrín González

Nickel is a hard, malleable and ductile metal that forms fundamentally divalent compounds, mostly nickel salts (Chloride, Sulfate, Nitrate) of bluish green color.

It is the most common cause of allergic contact dermatitis in patients undergoing patch tests.

Where do you find it?

In multiple everyday objects: jewelry, scissors, keys, doorknobs, coins, clothing buttons, belt buckles, headphones, mobile phones, among others.

Sweating and close contact with the skin facilitate absorption and can lead to symptoms.

How does allergy occur?

As we have explained in many of our contents, frequent exposure to an allergen, in this case nickel, increases the risk of sensitization and allergy.

It has been associated with the use of earrings or body piercings.

What symptoms can you have?

Common reactions are eczema-like lesions in the area of contact, red skin that itches.

Delayed reactions such as airborne reactions from the use of sprays or systemic contact dermatitis may also occur.
It can be the origin of dermatitis in professionals such as cashiers, jewelers, electricians, car mechanics, painters, among others.

What should you do?

You must go to your allergy specialist, who will assess your case, and if necessary, perform patch tests. And you will have to avoid the use of objects that contain nickel.

Any doubts?

Contact with us

Dra Jaritzy Negrín González
Allergy Specialist

Allergy to pine pollen and pine processionary caterpilar

Allergy to pine pollen and pine processionary caterpilar 1920 1280 Jaritzy Negrín González

Allergy to pine pollen is not common. It can become relevant in areas with high concentrations, for example in the Basque Country and Galicia.

Symptoms can be nasal, ocular or bronchial. Generally, the patient is monosensitive, that is, he has no allergy to other pollens.

What is the pine processionary caterpillar?

The processionary caterpillar is an insect that lives in pine trees and has 4 stages of development: moth, egg, larva and chrysalis. It receives the name of processionary because they parade as in a procession.

In their larval phase they have microscopic hairs whose function is to defend against possible predators. In the mature phase, after leaving the pine trees, the caterpillar can releases up to more than 1 million of these hairs

What are the symptoms produced by the pine processionary caterpillar?

More frequently, it causes itching and skin lesions in exposed areas (arms, legs and face) due to the penetration of the hairs. In children, injuries to the palms of the hands are typical because they try to catch the caterpillars.

Injuries can be:

-Dermatitis with scratching lesions and eczema.

-Contact urticaria which may be associated with angioedema of the eyelids.

-Less frequently, lesions such as vesicles or pustules.

It can also produce ocular symptoms such as conjunctivitis or keratitis.

Respiratory symptoms are less frequent, which can be associated with anaphylaxis.

Why do the symptoms occur?

The mechanism involved in the production of this reaction is usually mechanical or irritative, although it is sometimes produced by an IgE-mediated mechanism.

Who can affect?

It can produce symptoms in anyone who has been exposed to pine forest areas.

It has also been described as an occupational disease in resin collectors, lumberjacks, farmers or ranchers, due to their high exposure to caterpillars.

How can symptoms be treated?

If you present the symptoms described, you should request an assessment by your allergy specialist and the case will be evaluated.

Treatment is symptomatic according to the clinical picture: oral antihistamines, topical or oral corticosteroids. And in severe cases (anaphylaxis) it will be necessary to use adrenaline.

Do you have any doubt?

Dr Jaritzy Negrín González
Especialista en Alergología.


SHELLFISH ALLERGY 1920 1147 Jaritzy Negrín González

What is shellfish?

They are aquatic invertebrate animals, edible. They include crustaceans with more than 50,000 species such as shrimp, lobster, lobster, prawn… and molluscs made up of more than 100,000 species of bivalves (clam, mussel, oyster), cephalopods (octopus, cuttlefish, squid) and gastropods (snail, limpets). Not necessarily if you have an allergy to one of them, you have to have them all.

Shellfish are one of the most frequent causes of food allergy, its prevalence is linked to the frequency of its consumption.

Can you get a “shellfish allergy”?

The answer is YES. It is a hypersensitivity reaction with an immune mechanism, usually mediated by an antibody called IgE, which develops after ingestion, contact or inhalation of vapours from these foods.

Shellfish allergy is also considered an occupational disease that is, people who work in a food industry, due to the frequent handling of these foods, they can develop allergy.

Who is responsible?

Shelfish proteins are the allergens that cause allergy. Among these proteins we have Tropomyosin. It is a contractile protein, that is, it intervenes in the contraction of the muscle cells of all species of invertebrates. Allergenic tropomyosins have been described in numerous invertebrate species: crustaceans, molluscs, arachnids (dust mites) and cockroaches.

If you have a shellfish allergy, you may become allergic to dust mites or vice versa. But it is not necessarily a condition to have both allergies Remember that immune, genetic, and exposure factors are involved for an allergy to occur.

Other causative allergens are: arginin kinase,myosin light chain, calcium-fixing protein, hemocyanin,  paramyosin.

What symptoms can you have?

The most frequent allergic reactions to shellfish are those mediated by IgE, usually occurring whitin the first hour of exposure to the food. The most frequent symptoms are on the skin (hives, itching, erythema, angioedema); digestive, respiratory or all symptoms can also occur, which is what we call anaphylaxis.

What should you do if you’ve had suspicious symptoms of shellfish allergy?

You should go to an allergist. Initially, a detailed medical history of what has happened will be made and according to its assessment it will determine to carry out allergy tests: prick test and a blood test if necessary. It is also possible that an oral provocation test will need to be performed and the study of other shellfish other than the one involved should be evaluated to rule out or diagnose cross-reactivity which may happen because shellfish share homologous allergenic proteins.

If you are already diagnosed with shellfish allergy, what should you do?

You should avoid exposure to shellfish and if you have an accidental exposure follow the instructions of your allergist.

It usually consists of medication with antihistamine, corticosteroids and / or adrenaline as the case may be.

Dra Jaritzy Negrín González.
Allergi specialist.

Allergic Conjunctivitis

Allergic Conjunctivitis 1270 768 Jaritzy Negrín González

What is allergic conjunctivitis?

Allergic conjunctivitis It is the inflammation of the ocular conjunctiva caused by exposure to an allergen (pollen, dust mites, molds, animal epithelia, among others) causing an immune response mediated by specific antibodies called specific immunoglobulin E

  • It is considered the most frequent of eye allergies.

  • Depending on the causal allergen it can be perennial or seasonal.

  • Patients with allergic conjunctivitis usually have a family or personal history of allergy (atopy).

Symptoms of allergic conjunctivitis

  • Itching, tearing and redness of the conjunctiva in both eyes.

  • It may be associated with other allergic diseases such as asthma, rhinitis and atopic dermatitis.

  • It can cause visual discomfort.

What should you do if you have an allergic conjunctivitis?

Go to your allergy specialist to make a diagnosis, considering other diseases of the ocular surface.

An evaluation and relevant tests should be carried out according to each case and indicate treatment that may be: specific immunotherapy (allergy shots) or symptomatic treatment with oral antihistamines and / or eye drops, in addition to the avoidance of the causative allergen.

Other types of eye allergies:

Allergic contact dermatitis: it is an inflammatory reaction of the skin of the eyelids by direct contact with an external agent, for example cosmetics, creams, medicines, among others. Lesions appear after repeated exposures and after a period of sensitization. Diagnosis can be made with epicutaneous tests (Patch-Test) to suspicious agents. Avoiding the triggering factor,symptoms will improve.

Atopic dermatitis: it is an inflammatory disease of the skin, which can also affect the eyelids. The common lesion is eczema and usually produces severe itching.

Angioedema: is the inflammation of the subcutaneous and / or submucosal tissue, in this case of the eyelids, usually accompanied by hives when the mediator involved is histamine. Unlike angioedema mediated by a substance called bradykinin in which it is not associated with urticaria lesions and does not respond to treatment with antihistamines or corticosteroids.

“As always, at ClinicAl we remember that our consultations are available to those patients who have questions about their allergic disease. So if you need it, contact us and go to one of our consultations

Dra. Jaritzy Negrín González
Allergy Specialist

Pollen allergy

Pollen allergy 1270 768 Jaritzy Negrín González

Spring is coming and with it the symptoms in our pollen-allergic patients.

Pollens are microscopic grains, invisible to the human eye that are scattered in the air.

“In our area, the most frequent pollens are Cypress, Plane-tree, Parietaria, Grass, and Olive. Pollen levels increase depending on the time of year, for this reason not all pollen-allergic patients have symptoms in the same months of the year.”

You can know the pollen calendar and weekly count levels by accessing “Aerobiological Information Point of Catalonia” through this link:

“Pollen allergy can occur with rhinoconjunctival symptoms (sneezing, nasal or ocular itching, mucus, nasal congestion…) and/or bronchial symptoms (shortness of breath, cough, whistling…) You should go to your allergy specialist to find out which pollen or pollens are causing your symptoms and indicate proper treatment.”

If you are a patient allergic to pollen we can recommend:

  • Keep the windows of the house closed as possible. Ventilate the home for a short time and preferable first thing in the morning or at night.
  • Travel by car with the windows closed.
  • Hang clothes inside the house, not outside.
  • Avoid outdoor physical activities; especially when the pollen count is high.
  • The use of glasses is preferable to contact lenses, since pollen can be trapped between them and the eye.

Dr. Jaritzy Negrín González
Allergy Specialist