Peer-reviewed article
No demonstrated superiority of tropomyosin (Pen a 1) sIgE over crude shrimp sIgE in children.
Yanagida N, Yoshimoto H, Ogura K, Nagakura KI, Takahashi K et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This is a clinical laboratory study comparing two diagnostic tests for shrimp allergy in children. The study found that a specific protein marker (tropomyosin) was not superior to crude shrimp extract for predicting allergic reactions in oral food challenges. The research involved 204 children with a median age of 6.2 years.
Key points
- Tropomyosin-specific IgE and crude shrimp-specific IgE showed no significant difference in predicting oral food challenge outcomes (AUCs 0.622 vs 0.629, p=0.850)
- Strong correlation between the two markers (r=0.767) suggests tropomyosin is a major component of the crude extract
- Among 204 children, 16% (33) had positive oral food challenges
- Dust mite allergen showed weak correlation with both markers
- Oral food challenge remains essential for diagnosis despite serological testing
Limitations
This is a retrospective diagnostic accuracy study with no demographic details on country or population characteristics provided. The study does not evaluate any intervention for child well-being but rather compares diagnostic test performance.
Abstract
Background Tropomyosin (Pen a 1)-specific IgE (sIgE) is a proposed diagnostic marker for shrimp allergy; however, its superiority over crude shrimp sIgE is unclear. This study aimed to determine whether Pen a 1 sIgE is superior to crude shrimp sIgE for predicting oral food challenge (OFC) outcomes in children. Methods We retrospectively analyzed children who underwent OFCs using ≥40 g heated shrimp and had both shrimp sIgE and Pen a 1 sIgE data. Areas under the receiver operating characteristic curves (AUCs) were compared using the DeLong test, and the paired AUC difference with its 95% confidence interval (CI) was estimated. Results Of 204 patients (median age 6.2 years; 70% male), 33 (16%) had a positive OFC. The AUCs for shrimp sIgE (0.629; 95% CI, 0.535-0.723) and Pen a 1 sIgE (0.622; 95% CI, 0.524-0.718) did not differ significantly (difference, 0.007; 95% CI, -0.069 to 0.083; DeLong p = .850). Pen a 1 sIgE correlated strongly with shrimp sIgE (r = .767, p < .001). Among 190 patients with Dermatophagoides pteronyssinus (Der p) sIgE data, Der p sIgE correlated weakly with both markers (r= .321 and .217) and did not differ by OFC outcome (p = .612). Conclusion Superiority of Pen a 1 sIgE over crude shrimp sIgE was not demonstrated. The strong correlation suggests that tropomyosin is a major IgE-binding component of the crude extract. OFC remains essential.