Adverse reactions to biological modifiers - summary from 2011 CSACI meeting

This summary was compiled from tweets posted by Dr. Stuart Carr @allergydoc4kidz, the president of the Canadian Society of Allergy and Clinical Immunology (CSACI). The tweets were labeled #CSACI and they reached more than 10,000 people. I would strongly encourage you to post updates on Twitter from the CME conferences that you are planning to attend in the future.

Mariana Castells spoke on adverse reactions to biological modifiers:

There will be more and more adverse reactions to biologicals over time. Premedication (antihistamines, steroids) is not effective to prevent these reactions.

Mechanism of anaphylactic reactions

Anaphylactic reactions to monoclonal antibodies can be IgE-mediated or non-IgE-mediated. There are possibly IgG-mediated or complement-dependant or cytokine-based pathways for non-IgE reactions to monoclonal antibodies.

Desensitization

Avoidance of biological modifiers is preferable to desensitization, if possible.

Desensitization is TEMPORARY induction of clinical tolerance. It needs to be repeated before every exposure (or 2.5 half lives) for biologicals.

Desensitization is high risk, often used in critically ill patients, with no valid alternatives. Desensitization is temporary, antigen-specific, and only should be done by trained allergists. It impairs calcium influx, and impedes release of preformed mediators from mast cells. Antigen/IgE/FceRI complexes are not internalized following rapid desensitization.

Desensitization is NOT for type III or IV reactions, or Stevens-Johnson syndrome. Patients with desquamation, skin blistering, and serum sickness are NOT candidates for desensitization.

Most reactions occur towards the end of procedure, at final concentrations/doses. Patient can react with subsequent desensitizations, regardless of previously developed tolerance.

Related reading: Allergy to monoclonal antibodies: cutting-edge desensitization methods - Expert Reviews, 2012.

Disclaimer: The text was edited, modified, and added to by me. I was invited to speak on the topic of social media use by the allergists during the 2011 CSACI meeting.