Immune-Mediated Organ-Specific Reactions to COVID-19 Vaccines: A Retrospective Descriptive Study

Area of Science:

• Immunology
• Vaccinology
• Clinical Medicine

Background:

• COVID-19 vaccines, developed rapidly, can cause rare hypersensitivity reactions (HRs).
• Delayed HRs are suspected to be linked to vaccine excipients like polyethylene glycol (PEG) and polysorbate 80 (P80).
• Current diagnostic methods like skin patch tests are ineffective for delayed reactions.

Purpose of the Study:

• To evaluate the utility of lymphocyte transformation tests (LTT) for diagnosing delayed hypersensitivity reactions to COVID-19 vaccine excipients PEG and P80.
• To investigate the association between LTT results and specific types of hypersensitivity reactions.

Main Methods:

• Lymphocyte transformation tests (LTT) were performed on 23 patients with suspected delayed hypersensitivity reactions to COVID-19 vaccines.
• Tests involved exposure to polyethylene glycol (PEG) and polysorbate 80 (P80).
• Patient outcomes, including reaction type, hospitalization, and recovery time, were recorded.

Main Results:

• LTT was positive in 8 out of 23 patients (34.8%).
• Positive LTT results were observed in patients with neurological, hepatitis, and rheumatologic reactions.
• All patients with myopericarditis reactions showed negative LTT results.

Conclusions:

• Lymphocyte transformation tests (LTT) appear to be a valuable tool for identifying polyethylene glycol (PEG) and polysorbate 80 (P80) as causative agents in hypersensitivity reactions to COVID-19 vaccines.
• LTT may aid in the risk stratification of patients experiencing hypersensitivity reactions post-vaccination.