Hypersensitivity reactions to ethylene oxide: clinical experience

Area of Science:

• Nephrology
• Clinical Chemistry
• Biomaterials Science

Background:

• Hypersensitivity reactions can occur during hemodialysis, particularly with new dialyzer use.
• Ethylene oxide (ETO) sterilization is common for medical devices, but residual ETO can pose risks.

Purpose of the Study:

• To investigate the cause of acute hypersensitivity reactions observed in hemodialysis patients.
• To determine the association between ETO concentration in dialyzers and the occurrence of these reactions.

Main Methods:

• Observational study of hemodialysis patients experiencing acute reactions.
• Analysis of hollow-fibre dialyzers (cellulose ester and cuprammonium cellulose) for ETO concentration.
• Correlation of ETO levels in dialyzer components (potting vs. capillaries) with clinical reactions.

Main Results:

• Seven patients experienced grade 2 hypersensitivity reactions within the first minute of dialysis.
• Significantly higher ETO concentrations were detected in the polyurethane potting of the dialyzers compared to the capillaries.
• Reactions were mitigated when extensive rinsing of the dialyzers was employed.

Conclusions:

• The acute hypersensitivity reactions are presumed to be related to residual ETO in the dialyzers.
• ETO concentration in the dialyzer potting may be a critical factor in reaction development.
• Further investigation is warranted, though other mechanisms cannot be entirely excluded.