What Are Indications for Allergy Testing?

Patient Presentation
A 2-year-old female came to clinic with a rash that was not improving. She had a history of atopic dermatitis since infancy that was treated with lotion once a day. About 1 month previously, she had been given picrolimus at another facility but her mother did not apply it as a friend told her it was very strong medicine. The friend also told the mother that perhaps the child had food allergies as the cause of the rash, so the mother requested testing. The girl had no history of asthma, difficulty breathing, diarrhea or abnormal stools, bloating, rhinorrhea, and was following her 50-90% growth curves. The mother denied pruritis or irritability, or changes in the rash with different foods. The past medical history of two episodes of otitis media treated with amoxicillin was made. The family history was positive for asthma in the mother’s family and seasonal allergic rhinitis on both sides of the family. There was no known food, drug or animal allergies.

The pertinent physical exam showed a well-appearing female with normal vital signs. HEENT demonstrated no atopic pleats and the mucosa appeared normal. Lungs were clear. Skin examination showed diffuse dry skin especially on the arms, legs and trunk. She had several areas of redness on her left leg and ventral trunk. Behind the left knee there was a 4 cm round area with mild lichenification and erythema. There was no scale seen. She did pull at her arms and legs during the examination.

The diagnosis of atopic dermatitis was made. The mother was educated extensively verbally and with written documents about the natural history of atopic dermatitis and the importance of emollients as a mainstay of therapy. The mother was also educated about improved bathing practices and how and when other medications such as topical steroids should be used. Overall the plan was to begin an oral antihistamine to decrease pruritis, increase the frequency and amount of thick ointments, use of a low potency (Level VI) topical steroid to the swollen, reddened areas for 4-5 days, and bathing with an unscented body bar for soap. The physician didn’t recommend using the picrolimus at this time as a steroid had not been tried yet. The physician explained that although food allergies could be contributing to the atopic dermatitis, that it appeared that she had been undertreated. She also did not have other symptoms that pointed toward a food allergy. The mother agreed to implement the treatment plan and 1 month later the child’s skin had much improved with fewer dry spots and no areas of swelling. The lichenified area appeared to be improving slightly. The mother said that her daughter wasn’t itching as much either, now that she knew that grabbing clothing signaled itching. The mother still had concerns about food allergies but agreed to continue treating and monitoring the patient.

Discussion
When to send a patient to an allergist/immunologist sometimes is very clear such as a patient with angioedema and respiratory problems after an insect sting or contact with latex, but many common problems may need appropriate followup and monitoring before a referral is considered.

Allergists are trained to perform and interpret diagnostic information that may not be available to generalists such as specific in vitro testing, skin testing and can perform provocative challenges such as methacholine challenges for asthma. Additionally, an allergist/immunologist makes daily and emergency management plans and gives education to carry out those plans for challenging patients such as those with potential anaphylaxis or immune deficiency. Other treatment modalities available include drug desensitization and immunotherapy.

Allergists/immunologists are usually necessary for diagnosis and treatment of:

  • Anaphylaxis
  • Angioedema and urticaria
  • Allergic disease caused by drugs, food, and latex
  • Allergic disease associated with
    • Allergic bronchopulmonary aspergillosis,
    • Aspirin exacerbated respiratory disease
    • Occupations – allergic sensitization to food, animals, etc.
  • Hypersensitivity pneumonitis
  • Insect hypersensitivity
  • Primary immune deficiency

Allergists/immunologist may also be helpful for:

  • Asthma
    • Confirming the diagnosis
      • Challenge testing including exercise or methacholine
      • Correlation of history with specific IgE testing
    • Identifying etiology/role of agent
      • Environmental cause (ie dust mite, pollen, etc.)
      • Food
      • Drug
      • Occupational or other exposure
    • Improving management/outcome of patients with
      • Potentially fatal asthma
      • Moderate to severe persistent asthma
      • Poor control despite apparent appropriate therapy
      • Using excessive amounts of medication
      • Poor control because of possible non-adherence, education, support, including improving environmental management
      • Multiple hospitalizations and/or emergency department visits
      • Associated rhinitis or sinusitis
    • Improving by
      • Education
      • Environmental control
      • Optimal medication choice and use
  • Conjunctivitis or Rhinitis
    • Confirming the diagnosis
      • Seasonal allergic rhinitis/conjunctivits
      • Other cause
    • Identifying etiology/role of agent
      • Correlation of history with specific IgE testing
      • Specific allergen testiing
    • Improving management/outcome through
      • Education
      • Environmental control
      • Optimal medication choice and use, including immunotherapy in certain patients
  • Dermatitis
    • Confirming the diagnosis
      • Atopic dermatitis
      • Contact dermatitis – patch testing
      • Other cause
    • Identifying etiology/role of agent
      • Environmental cause (ie dust mite, etc.)
      • Food
    • Improving management/outcome of patients with
      • Poor control despite apparent appropriate therapy
      • Using excessive amounts of medication
      • Poor control because of possible non-adherence, education, support
    • Improving by
      • Education
      • Optimal medication choice and use
  • Sinusitis
    • Confirming the diagnosis
      • Allergic fungal sinusitis
      • Seasonal allergic rhinitis
      • Immunodeficiency
    • Improve management/outcome through
      • Education
      • Environmental control
      • Optimal medication choice and use, including immunotherapy in certain patients including treatment of
        • Associated immunodeficiency
        • Fungal disease
        • Associated eosinophilic inflammation
        • Nasal polyps

Learning Point
Indications for allergy testing include:

  • Asthma – patients exposed to indoor allergens with persistent asthma
  • Allergy, suspected – to food, drug, insect sting, latex or other similar identifiable allergens
  • Rhinitis – patient’s symptoms not controlled by avoidance and medication

Questions for Further Discussion
1. What standard extracts for allergic skin testing are available?
2. How does immunotherapy for allergies work?
3. What is the definition of food allergy?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Allergy, Food Allergy and Eczema.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Li JT. Allergy Testing Am Fam Physician. 2002 Aug 15;66(4):621-625. Available from the Internet at http://www.aafp.org/afp/2002/0815/p621.html (rev. 8/15/2002, cited 5/15/2012).

American Academy of Allergy Asthma and Immunology. How the Allergist / Immunologist Can Help: Consultation and Referral Guidelines Citing the Evidence. J Allergy Clin Immunol 2006 Feb;117(2 Suppl Consultation):S495-523. Available from the Internet at http://www.guidelines.gov/content.aspx?id=9334&search=allergy+testing+in+children (rev. 2/2006, cited 5/24/12).

American Academy of Allergy Asthma and Immunology. How the Allergist / Immunologist Can Help: Consultation and Referral Guidelines Citing the Evidence. Primary Care Summary. Available from the Internet at http://www.aaaai.org/practice-resources/Consultation-and-Referral-Guidelines/Primary-Care-Summary.aspx (rev. 2012, cited 5/15/12).

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    5. Patients and their families are counseled and educated.
    8. Health care services aimed at preventing health problems or maintaining health are provided.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Interpersonal and Communication Skills
    17. A therapeutic and ethically sound relationship with patients is created and sustained.

  • Professionalism
    20. Respect, compassion, and integrity; a responsiveness to the needs of patients and society that supercedes self-interest; accountability to patients, society, and the profession; and a commitment to excellence and on-going professional development are demonstrated.
    21. A commitment to ethical principles pertaining to provision or withholding of clinical care, confidentiality of patient information, informed consent, and business practices are demonstrated.
    22. Sensitivity and responsiveness to patients’ culture, age, gender, and disabilities are demonstrated.

  • Systems Based Practice
    23. Differing types of medical practice and delivery systems including methods of controlling health care costs and allocating resources are known.
    24. Cost-effective health care and resource allocation that does not compromise quality of care is practiced.

    Author

    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital