Presentation on theme: "Skin Prick Testing: What Can We Still Improve? Reporting Results Paul A. Greenberger, M.D. Workshop 5 5 December 2011."— Presentation transcript:
Skin Prick Testing: What Can We Still Improve? Reporting Results Paul A. Greenberger, M.D. Workshop 5 5 December 2011
History.…”Doctor Allergist…………… Heal Thyself” Call to action : Drs. Gail Shapiro and Louis Mendelson Improve content of and standardize Skin Testing and Immunotherapy records Enlist attention and support of fellowship program directors 1995 Practice Parameters AAAAI, ACAAI, JCAAI …….
Allergy Diagnostic Testing: An Updated Practice Parameter AAAAI, ACAAI, JCAAI Ann Allergy Asthma Immunol 2008;100:S1- S148 “The peak reactivity of prick/puncture tests is minutes at which time both wheal and erythema diameters (or areas) should be recorded in mm and compared to positive and negative controls
Allergy Diagnostic Testing: An Updated Practice Parameter AAAAI, ACAAI, JCAAI 2008 “Qualitative scoring (0-4+) is no longer used by many clinicians because of interphysician variability in this method of scoring and interpretation”
Reporting Results Negative control (saline or 50% glycerinated HSA- saline) Positive control (histamine) Test allergen, medication, latex, venom, chemicals Timing of reading should be at the peak Histamine 8-10 minutes Mast cell secretagogues (9% codeine) minutes Allergens (15-20 minutes)
Reporting Results –The Medical Record Source of extracts on report form/record? Concentration of extract? Measurement by ruler of wheal and erythema for each allergen?
Format for Chart Allergen Concentration: Extract Manufacturer: Percutaneous ____/_____ Intradermal ____/_____
How Would You Report This Result?
Doing the Math Mean Wheal Diameter = Largest diameter of wheal D + Largest diameter perpendicular to D (d) = D + d 2
Expected Wheal Size of the Prick Test Response to Histamine is 2-7 mm
Does Immediate Blotting of the Extract Interfere with Results?
Wheal or Wheal and Erythema? “Although some investigators have advocated the primary importance of the wheal diameter, both erythema and wheal should be measured and recorded in mm for appropriate comparisons and positive (ie histamine) and negative controls (ie buffered diluent or 50% glycerinated extracts) AAAAI, ACAAI, JCAAI practice parameter 2008”
What is the minimum diameter of the prick skin test that matters? “3 mm diameter (with equivalent erythema) more than the diluent control done at the same time is required as proof of the presence of cutaneous allergen specific IgE” AAAAI, ACAAI, JCAAI practice parameters 2008