[Performance validation and clinical application evaluation of fluorescent magnetic particle chemiluminescence method for the determination of sIgE].

Abstract

To evaluate the analytical performance of a specific IgE (sIgE) quantitative detection system and explore the clinical application effect of dust mite extract and component detection. The fluorescent magnetic particle chemiluminescence method was used to verify the analytical performance of sIgE for house dust mite (D1), dust mite (D2) extracts, and their components (Der p 1, Der p 2, Der p 10, and Der p 23), including precision, limit of blank (LoB), limit of detection (LoD), linear range, and interfering factors. This is a retrospective cohort study. A total of 50 patients with allergic rhinitis and 50 patients with allergic asthma diagnosed at Zhongshan Hospital Affiliated to Fudan University from January 2022 to August 2023 were selected, along with 70 apparently healthy individuals who underwent physical examinations in the hospital as the healthy control group. The positive rates of each sIgE component in the three groups were compared, and the receiver operating characteristic (ROC) curve for diagnosing dust mite allergy was plotted. The results showed that the fluorescent magnetic particle chemiluminescence method for detecting sIgE demonstrated good repeatability and intermediate precision within the range of 0.1-100 kU/L. The LoB, LoD, and linear range all met the specified requirements. Except for Der p 10, which was interfered by the presence of conjugated bilirubin and free bilirubin (exceeding 40 mg/dl), the detection of other allergens was not significantly affected by common endogenous substances. In healthy individuals, 10% had positive sIgE for dustmite extract; in asthmatic and allergic rhinitis patients, the positive rates were 70% and 82%, respectively. The double positive rate of D1 and D2 in the healthy group was 8.6%, while in asthmatic and allergic rhinitis patients, it was 66% and 70%, respectively. When 0.35 kU/L was used as the threshold, the sensitivity of sIgE for dust mite extract to predict component positivity was 100%, specificity was 61.5%, positive predictive value (PPV) was 80.2%, and negative predictive value (NPV) was 100%. When the threshold was optimized to 0.78 kU/L, the sensitivity was 96.8%, specificity was 92.1%, PPV was 95.2%, and NPV was 94.6%. In conclusion, the repeatability, intermediate precision, LoB, LoD, linear range, and anti-interference ability of the fluorescent magnetic particle chemiluminescence method for detecting sIgE meet the requirements of laboratory quality management. This ensures detection quality, meets clinical needs, and can be used for the auxiliary diagnosis of allergic diseases.