Platelet-activating factor acetylhydrolase is a biomarker of severe anaphylaxis in children.

Abstract

BACKGROUND:

There is limited ability to predict the severity of allergic reactions in children. Data derived predominantly from adults have implicated the platelet-activating factor pathway as a potential contributor to severe anaphylaxis. In this study, we sought to prospectively assess involvement of key components of the platelet-activating factor pathway in pediatric patients with anaphylaxis.

METHODS:

Forty-six pediatric patients (<18 years) presenting with acute anaphylaxis were assessed. Anaphylaxis severity was graded and serum anaphylaxis markers were measured acutely and in 36 children who returned for follow-up >4 weeks after their acute presentation. These markers were compared with pediatric laboratory reference sera.

RESULTS:

Severe anaphylaxis was experienced by 12/46 (26%) and mild-moderate anaphylaxis in 34/46 (74%) children. Platelet-activating factor acetylhydrolase (PAF-AH) activity was inversely associated with severe anaphylaxis: 9/12 children with severe anaphylaxis had reduced PAF-AH activity as compared with 14/34 with mild-moderate anaphylaxis (p < .05). Furthermore, 3/3 children who required intensive care had markedly reduced mean PAF-AH (nmol/ml/min) (13.73, 95%CI: 7.42-20.03) versus 20/23 who required ward/emergency department care (17.81, 95%CI: 16.80-18.83; p < .05). In children with anaphylaxis, PAF-AH during acute anaphylaxis was unchanged relative to the child's basal levels (mean, 17.26, 95%CI: 16.10-18.42 vs 17.50, 95%CI: 16.21-18.78, p = .63) and was lower than healthy pediatric controls (mean 19.21; 95%CI:18.21-20.21; p < .05).

CONCLUSION:

Decreased serum PAF-AH activity is a biomarker of severe anaphylaxis. Levels of this enzyme do not change from basal levels during acute anaphylaxis. Our results show that PAF-AH is a biomarker of anaphylaxis severity in children. This key regulatory enzyme may modulate susceptibility to severe anaphylaxis.

• Authors: Julia E M Upton, Jennifer A Hoang, Matilde Leon-Ponte, Yaron Finkelstein, Yue Jennifer Du, Khosrow Adeli, Thomas Eiwegger, Eyal Grunebaum, Peter Vadas
• Journal: Allergy (Allergy) Vol. 77 Issue 9 Pg. 2665-2676 (09 2022) ISSN: 1398-9995 [Electronic] Denmark
• PMID: 35396721 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2022 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

Chemical References

• Biomarkers
• Platelet Activating Factor
• 1-Alkyl-2-acetylglycerophosphocholine Esterase

Topics

• 1-Alkyl-2-acetylglycerophosphocholine Esterase
• Adult
• Anaphylaxis (diagnosis, etiology)
• Biomarkers
• Child
• Humans
• Platelet Activating Factor (metabolism)