Drug-induced IgA vasculitis in children and adults: Revisiting drug causality using a dual pharmacovigilance-based approach

Objectives: IgA vasculitis (IgAV) is an immune complex small-vessel vasculitis. Drug-induced IgAV cases were rarely reported in the literature. Drug causality assessment is challenging as many other etiological factors can be involved. We performed a pharmacovigilance study to identify the main drugs reported to induce IgAV.

Methods: We used the French pharmacovigilance database (FPVD) and the WHO global individual case safety reports database (VigiBase) to retrieve IgAV cases. Cases from the FPVD were reviewed by two investigators using predefined criteria. Disproportionality analyses (case - non-case approach) were conducted in VigiBase to identify drugs significantly associated with IgAV reporting.

Results: Of the 467 IgAV cases retrieved from the FPVD, 115 (47 children and 68 adults) have been assessed as definite or probable, reported with 178 suspected drugs. Overall IgAV cases were mainly male (58%), with a median age of 33.5 (8.0-63.3) years. No death was reported. Besides, we identified 1558 possible IgAV cases in VigiBase. Among them, 40 were associated with a disproportionality in IgAV reporting. Drugs were mainly vaccines, antibiotics and TNF-α blockers, these finding being consistent in both databases. IgAV reporting with TNF-α blockers was significantly associated with their use in inflammatory bowel diseases, psoriasis or ankylosing spondylitis compared to other indications.

Conclusions: Our systematic study enables the identification of culprit drugs in drug-induced IgAV. These results strengthen the immune pathophysiology of IgAV and the role of underlying disease. The list of suspected drugs may be useful for physicians to manage patients with IgAV and consider appropriate drug discontinuation.

Key messages: What is already known about this subject? IgA vasculitis has multifactorial etiology. To date, possible culprit drugs have been reported only in case reports. What does this study add? Using a dual pharmacovigilance-based approach, we identified drugs associated with the occurrence of IgA vasculitis, such as all types of vaccines, major antibiotics and immunomodulatory agents, mainly TNF-α blockers. How might this impact on clinical practice or future developments? Physicians should be aware of drug-induced IgA vasculitis and we provide evidence on the most frequent implicated drugs.