Moreover, we found that patients with donor KIR haplotype A had a lower risk of CMV-reactivation than patients with donor KIR haplotype B. Although this result is in contradiction with published studies [23, 28], a recent study in renal transplant patients also showed that depending on HLA-type, KIR haplotype A might be protective against infection such as CMV [24]. Here, KIR3DL1 is linked to infection.