Diagnostic accuracy of the passive mast cell activation test in neuromuscular blocking agent-induced perioperative anaphylaxis in a tertiary hospital in China: a diagnostic accuracy study.

OBJECTIVES

The passive mast cell activation test (pMAT) is a novel in vitro assay designed to complement existing tools like the skin test (ST) and basophil activation test (BAT) for allergen identification. This study aimed to validate the diagnostic accuracy of pMAT specifically for neuromuscular blocking agent (NMBA)-induced perioperative anaphylaxis (POA).

DESIGN

A diagnostic accuracy study.

SETTING

A tertiary hospital in Beijing, China.

PARTICIPANTS

44 patients with suspected POA were enrolled. Participants were stratified into groups based on ST and/or BAT. The NMBA-allergic group comprised 15 patients with confirmed NMBA allergy while the non-NMBA-allergic group consisted of 29 individuals without NMBA allergy.

INTERVENTIONS: All participants underwent pMAT testing for relevant NMBA.

PRIMARY AND SECONDARY OUTCOME MEASURES: The diagnostic performance of pMAT for NMBA was assessed by measuring sensitivity, specificity, likelihood ratios and the Youden index. An exploratory analysis evaluated its performance in diagnosing antibiotic-induced allergies within the same population.

RESULTS

For NMBA allergy, pMAT demonstrated high diagnostic accuracy (90.9%; 95% CI 77.4% to 97.1%) with excellent sensitivity (93.3%; 95% CI 66.0% to 99.7%) and specificity (89.7%; 95% CI 71.5% to 97.3%). This was reflected in a high positive likelihood ratio (9.05; 95% CI 3.06 to 26.57), a low negative likelihood ratio (0.07; 95% CI 0.01 to 0.50), a Youden index of 0.83 and a Cohen's kappa of 0.804 (indicating substantial agreement with the reference standard). In contrast, pMAT showed reduced performance for antibiotic allergy, with an accuracy of 79.5% (95% CI 64.3% to 89.7%), sensitivity of 66.7% (95% CI 30.9% to 91.0%), specificity of 82.9% (95% CI 65.7% to 92.8%) and a kappa of 0.378 (fair agreement).

CONCLUSIONS

pMAT demonstrated high diagnostic accuracy for NMBA allergy, filling critical gaps in current POA diagnostic workflow. Its robust performance supports its clinical utility as a complementary tool alongside ST and BAT.

TRIAL REGISTRATION NUMBER: ChiCTR2400084268.