Does OM-85 BV prophylaxis trigger autoimmunity in IgA deficient children?

Area of Science:

• Immunology
• Pediatrics

Background:

• Selective IgA deficiency (IgAD) is the most common primary antibody deficiency.
• While often asymptomatic, some IgAD children experience frequent infections, prompting investigation into prophylactic measures.
• OM-85 BV, a bacterial lysate, stimulates mucosal immunity and Th-1 responses, raising questions about its potential to induce autoimmunity.

Purpose of the Study:

• To investigate whether OM-85 BV prophylaxis triggers autoimmunity in children with IgA deficiency (IgAD).
• To assess the development of clinical autoimmune findings and autoantibodies over a four-year follow-up period in IgAD children receiving OM-85 BV.

Main Methods:

• Sixty-three children with sporadic IgAD and recurrent infections were enrolled, excluding those with existing autoimmune features or immunosuppressant treatment.
• Patients were randomized into two groups: one receiving OM-85 BV (n=37) and a control group receiving no prophylaxis (n=26).
• Autoimmunity screening included clinical evaluation and autoantibody testing (ANA, ANA profile, ANCA, aCL, RF, direct Coombs, anti-T, anti-M) at baseline and during follow-up.

Main Results:

• The study group had a mean age of 102.9 months, with infections occurring 6.2 times per year.
• Sixteen patients (25.4%) showed ANA positivity; however, frequencies of ANA, ANCA, and RF positivity did not significantly differ between the OM-85 BV group and the control group.
• No significant differences in clinical or laboratory markers of autoimmunity were observed between the groups over the 48.3-month follow-up.

Conclusions:

• OM-85 BV prophylaxis did not appear to trigger significant clinical or laboratory signs of autoimmunity in IgAD children.
• The frequency of ANA positivity remained comparable to previous reports and was not influenced by OM-85 BV.
• Further research is needed to clarify the potential of repeated bacterial lysate courses to induce autoimmunity; no treatment-related side effects were reported.