Low platelet count: Predictor of death and graft loss after liver transplantation

BACKGROUND: The impact of platelets on liver transplantation (LT) is well recognized, but not completely understood. Platelets exert dichotomous effects on the graft and on the patient. On the one hand, they are essential for primary hemostasis and tissue repair and regeneration. On the other hand, they support ischemia/reperfusion injury and inflammatory processes. Recent evidence has shown a new role for platelet count (PC) in predicting outcomes after LT. AIM: To evaluate if low PC is a predictor of short- and long-term outcomes after LT. METHODS: Four hundred and eighty consecutive LT patients were retrospectively assessed. PC from the preoperative to the seventh postoperative day (POD) were considered. C-statistic analysis defined the ideal cutoff point for PC. Cox regression was performed to check whether low PC was a predictor of death, retransplantation or primary changes in graft function within one year after LT. RESULTS: The highest median PC was 86 × 10(9)/L [interquartile range (IQR) = 65–100 × 10(9)/L] on seventh POD, and the lowest was 51 × 10(9)/L (IQR = 38–71 × 10(9)/L) on third POD. The C-statistic defined a PC < 70 × 10(9)/L on fifth POD as the ideal cutoff point for predicting death and retransplantation. In the multivariate analysis, platelets < 70 × 10(9)/L on 5POD was an independent risk factor for death at 12 mo after LT [hazard ratio (HR) = 2.01; 95% confidence interval (CI) 1.06-3.79; P = 0.031]. In the Cox regression, patients with PC < 70 × 10(9)/L on 5POD had worse graft survival rates up to one year after LT (HR = 2.76; 95%CI 1.52-4.99; P = 0.001). CONCLUSION: PC < 70 × 10(9)/L on 5POD is an independent predictor of death in the first year after LT. These results are in agreement with other studies that indicate that low PC after LT is associated with negative outcomes.