Neutropenia in kidney and liver transplant recipients: Risk factors and outcomes.

No studies have directly compared the key characteristics and outcomes of kidney (KTx) and liver transplantation (LTx) recipients with neutropenia. In this single-center, retrospective, cohort study, we enrolled all adult patients who received a KTx or LTx between 2000 and 2011. Neutropenia was defined as 2 consecutive absolute neutrophil count (ANC) values <1500/mm3 in patients without preexisting neutropenia. The first neutropenia episode occurring during the first year post-transplantation was analyzed. A total of 663 patients with KTx and 354 patients with LTx met the inclusion criteria. Incidence of neutropenia was 20% in KTx and 38% in LTx, respectively. High-risk CMV status and valganciclovir (VGCV) use were significant predictors of neutropenia for KTx recipients, but only VGCV use vs nonuse in LTx recipients. Neutropenia was associated with worse survival in KTx recipients (adjusted HR 1.95, 95% CI 1.18-3.22, P<.01), but not in LTx recipients (adjusted HR 0.75, 95% CI 0.52-1.10, P=.15). Sixteen acute rejection episodes were associated with preceding neutropenia in KTx recipients (HR 1.77, 95% CI 1.16-2.68, P=.007) and 24 acute rejection episodes in LTx recipients (HR 1.41, 95% CI 0.97-2.04, P=.07). Incidence of infection was similar in patients with and without neutropenia among KTx and LTx recipients.