Significantly lower postoperative infection rates have been observed in patients with haemophilia when postoperative FVIII activity levels are maintained at higher levels (≥80% over the first 2 postoperative weeks) than currently recommended by guidelines (120% at surgery down to 50% at 2 weeks postsurgery).20 Trough FVIII activity levels in this patient were as low as 40% 5 days after surgery, raising the theoretical possibility of an association with the infection. The gene discussed is F8; the disease is infection.