Development and Performance Evaluation of External Quality Controls for Allergen-Specific Immunoglobulin E Tests.
10.15263/jlmqa.2017.39.2.97
- Author:
Ae Ran CHOI
1
;
Jee Hae KIM
;
Eui Sik LEE
;
Hyeyoung LEE
;
Jihyeong RYU
;
Ki Hyun PARK
;
Jihyang LIM
;
Eun Jee OH
Author Information
1. Department of Laboratory Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea. ejoh@catholic.ac.kr
- Publication Type:Original Article
- Keywords:
Pooled serum;
Allergen-specific immunoglobulin E;
Stability;
External quality control
- MeSH:
Allergens;
Immunoglobulin E*;
Immunoglobulins*;
Methods;
Quality Control*
- From:Journal of Laboratory Medicine and Quality Assurance
2017;39(2):97-105
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Many companies have developed different methods and products for allergen-specific immunoglobulin E (IgE) tests. Because there is no standardised reference method, external quality assessment (EQA) is important for allergen-specific IgE test to ensure the comparability and reliability of the results from different laboratories. We prepared specimens for EQA of allergen-specific IgE tests and evaluated their stability. METHODS: Four pooled sera with 24 selected allergen-specific IgE levels were prepared and stored at −80℃. The stability of allergen-specific IgE levels was assessed on days 1, 7, and 14 at −20℃, 2℃ to 8℃, and 20℃ to 25℃, and then after 3 months at −80℃. Mock proficiency tests were performed with the four sets of prepared external quality controls for six laboratories, using the commercial multiple allergen simultaneous test (MAST) methodology. RESULTS: About 150 specimens (650 µL each) for EQA were prepared; randomly selected specimens showed similar IgE levels for the 24 allergens (±1 class). The levels of allergen-specific IgE remained stable throughout the study period (P>0.05). Although mock survey results from six laboratories using four MAST assays revealed some variability with a difference (2–3 class), no consistent differences were observed through the allergens or MAST methods. Qualitative results from the mock survey showed 85.4% (cut-off of class 1) and 81.3% (cut-off of class 2) concordance with the results from ImmunoCAP (Phadia, Sweden). CONCLUSIONS: The pooled sera prepared for allergen-specific IgE tests might be adequate and useful for EQA.
