New technology provides prompt, accurate allergy diagnosis

Diagnosing allergy remains a big challenge to physicians, and can be a bane of suffering for allergy patients. However, a new diagnostic technology is offering a boon of relief for many patients.

An allergy is an abnormal reaction of the body to one or more substances that are usually harmless to most people. More than 20 percent of Filipinos have allergy symptoms and allergy studies show that the prevalence is 21 percent in children, 26 percent in teenagers, and 36 to 47 percent in adults.

Allergic reactions can manifest in many ways, which the physician might attribute to something else other than allergy. It can be present as simple abdominal and skin manifestations, hay fever, itchy eyes and respiratory symptoms, including asthma, and potentially fatal presentations such as anaphylaxis or shock.

The presence of rashes on the surface of the skin is a normal reaction of the immune system when an allergen is introduced in the body. An allergen is any substance that causes an allergic reaction. For someone with an allergy, the body’s immune system treats the allergen as an invader and reacts inappropriately resulting in harm to the person.

There are no immunizations or complete treatment for allergies. Health experts are one in saying that the best prevention is to be aware of the triggering factors and avoid them. To determine the types of allergens to which a person is allergic to, allergy testing should be done. An allergy test is any of several tests used to determine the substances to which a person is allergic.

Skin tests are the most common. They are more useful for respiratory allergies, a penicillin allergy, and insect bite allergies. However, skin testing is almost never performed to detect food allergies because of the high risk of causing a severe allergic reaction. Skin tests are more reliable when testing for airborne substances, such as animal dander or pollen.

In a skin test, a small amount of suspected allergy-causing substance is placed onto the skin, which is then scratched or pricked so that the allergen is introduced under the skin. In the case of children or in those with diffused skin rashes, the skin test cannot be done immediately because the rashes might interfere with the results of the test.

Latest technology

In cases like these, there is no more need to wait for the rashes to disappear before conducting an allergy diagnosis. The UniCAP or ImmunoCAP technology, the latest state-of-the-art technology in allergy testing, is now available in various hospitals and laboratories all over Metro Manila and in Davao. Physicians and patients have welcomed this as a big boost to allergy diagnosis.

A good case in point is that of a physician’s daughter, who developed rashes on both hands and feet. Suspecting allergy, the doctor-mother brought her daughter to the laboratory for diagnostic tests. Immunoglobulin E (IgE) test was above the normal 100, which may be seen in allergy cases.

She then gave her daughter some medicines for a 10-day treatment, after which the rashes still persisted. This prompted the doctor to bring her daughter to an allergy specialist. But before doing so, she requested for additional allergy screening tests, such as Phadiatop (to differentiate different types of allergy) and Fx5 (to determine the presence of antibodies in blood against common food allergens). This time, the result of the total IgE test was a high level of 405.

The allergologist confirmed that the patient, indeed, had an allergy. However, skin test could not be done yet because of the diffused skin rashes. The doctor-mother was anxious for an immediate result and management of her daughter’s ailment.

It took three weeks for the skin rashes to subside which seemed like endless suffering for the patient and anxiety for her mother. This time, a stronger drug for allergy was added to the previous medicine being taken by the patient.

Allergens and allergy tests

The UniCAP or ImmunoCAP technology can provide an early allergy diagnosis in cases when the traditional skin test could not be done. In the UniCAP system, a blood sample is all that is needed to determine which of the over 500 allergens causes the patient’s specific allergic reaction.

In a study published in the Journal of Allergy and Clinical Immunology, the UniCAP technology demonstrated superior reliability and accuracy, compared to four other tests, including the radioallergosorbent (RAST) blood test, once considered the standard for allergy blood testing.

Other cases and conditions that may require the use of the Pharmacia UniCAP System are allergic infants, atopic dermatitis and infantile eczema, extensive skin lesions which render skin testing difficult; patients who have already taken antihistamines since these will suppress the wheal and flare reaction of skin testing; patients with over-sensitive skin (dermatographism); anaphylactic reactions to drugs where skin testing can potentially cause the anaphylaxis itself, and older patients with wrinkled skin, making skin testing technically difficult.

The UniCAP technology was developed by Pharmacia Diagnostics, represented in the Philippines by Trianon International. Pharmacia Diagnostics is a division of Pharmacia Corp. based in Uppsala, Sweden, a world leader in invitro diagnostic research and product innovation.

There are now 24 hospitals and major laboratories where Pharmacia UniCAP 100E may be availed of. These are Makati Medical Center, Manila Doctors Hospital, Philippine General Hospital, The Medical City, UERM Medical Center, Victor Potenciano Medical Center, Manila Adventist Medical Center, St. Martin Maternity and Pediatric Hospital, Perpetual Help Medical Center, Bautista Hospital, LMC Hospital, Crisostomo General Hospital, Our Savior Hospital, Advent Specialist, Asia Pacific Laboratory, Asiatic Laboratory, Best Diagnostic Inc., Clinica Manila, Healthway Medical Clinics (all branches), Medic World, Medipoint, Mt. Gilead Diagnostics and Medical Services, and Our Lady of Mercy Diagnostics Center (Davao).