Long-term prognosis of vaccine-induced contact allergy to aluminium: Third patch-test with additional test preparations.

BACKGROUND: A high incidence of local itching subcutaneous nodules and aluminium allergy was observed in clinical trials of a new aluminium adsorbed pertussis vaccine in Gothenburg, Sweden, in the 1990s. A total of 495 children with itching nodules were patch tested with aluminium chloride hexahydrate 2% and an empty Finn Chamber®, 377 (76%) with positive reactions. When 241 of them were re-tested some years later 186 (3 out of 4) had unexpectedly lost their patch test reactivity. AIM: To investigate the long-term prognosis of vaccine-induced contact allergy to aluminium by a third patch test about 20 years after Patch test I. METHODS: Twenty individuals with positive and 11 with negative results in Patch test II were tested a third time with the same sensitisers as in in the first two tests. Three additional aluminium preparations were also tested. RESULTS: A total 15 out of 20 persons with positive results in the second test had lost their patch test reactivity. Two of 11 with negative tests had turned positive again. The addition of the preparations gave no conclusive results. CONCLUSION: Contact allergy to aluminium caused by vaccination with aluminium-adsorbed vaccines in childhood seems to fade away with time as measured by loss of patch test reactivity.

Long-term clinical course and prognosis of vaccine-related persistent itching nodules (1997-2019): An observational study.

Background: Vaccines adsorbed to aluminium can induce long-lasting intensely itching subcutaneous nodules (granulomas) at the injection site as well as contact allergy to aluminium. In clinical trials of a new acellular pertussis vaccine performed in the 1990s (Gothenburg, Sweden) with 76 000 participants, itching nodules were reported in 745 children. A positive patch test to aluminium was verified in 77% of the tested children with itchy nodules. Aim: To describe the long-term clinical course and prognosis of vaccine-related itching nodules caused by aluminium-containing pediatric vaccines and to estimate the risk for new symptoms after future vaccination with aluminium-containing vaccines. Methods: 745 children with vaccine-related itching nodules were followed by regular interviews/questionnaires for more than 20 years. 723 of them received a booster dose of diphtheria/tetanus vaccine either with or without aluminium adjuvant during the follow-up time. Results: Most study participants (86%) reported a full recovery from their itching nodules after a median duration of 6.6 years. Only a few of the diphtheria/tetanus-booster-vaccinated children (3%) reported mild transient itching and swelling at the new injection site. Conclusion: Vaccine-induced itching granulomas caused by an aluminium-adsorbed acellular pertussis toxoid vaccine seem to disappear over time. Future vaccinations with aluminium-adsorbed vaccines can be performed with little risk for new itching nodules later in life.