PRTN3 and granulomatosis with polyangiitis: Such links have been described for Staphylococcus aureus, where toxic shock syndrome toxin-1 (TSST-1)-producing strains increase relapse risk in granulomatosis with polyangiitis [21], and for Bartonella henselae endocarditis, which has been associated with PR3-ANCA positivity and crescentic glomerulonephritis [22].