TNF and vasculitis: In the second patient it is possible that underlying but undiagnosed IgA nephropathy was present (considering the presence of hematuria and proteinuria in the previous years); however, the strong correlation of symptoms with adalimumab administration, recurrence of vasculitis at drug rechallenge and complete resolution of heavy proteinuria after drug discontinuation suggest that the use of an anti-TNF agent was an important component of the disease cause.