Retrospective Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Jan 27, 2019; 11(1): 99-108
Published online Jan 27, 2019. doi: 10.4254/wjh.v11.i1.99
Low platelet count: Predictor of death and graft loss after liver transplantation
Pedro Beltrame, Santiago Rodriguez, Ajacio Bandeira de Mello Brandão
Pedro Beltrame, Santiago Rodriguez, Ajacio Bandeira de Mello Brandão, Graduate Program in Medicine: Hepatology, School of Medicine, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre 90050-170, Brazil
Pedro Beltrame, Ajacio Bandeira de Mello Brandão, Liver Transplantation Group, Santa Casa de Misericórdia de Porto Alegre, Porto Alegre 90035-072, Brazil
Author contributions: Beltrame P conceptualized and designed the data, collected the data, analyzed and interpreted the data, drafted the article, and critically revised the article; Rodriguez S collected the data, and critically revised the article; Brandão ABM conceptualized and designed the data, analyzed and interpreted the data, drafted the article, and critically revised the article; all authors have read and approved of the final version of the article.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of Santa Casa de Misericórdia de Porto Alegre (No. 1.183.375).
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: The authors have no financial relationships relevant to this article to disclose. Santiago Rodriguez is a CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) scholarship recipient.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Ajacio Bandeira de Mello Brandão, MD, Associate Professor, Graduate Program in Medicine: Hepatology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Rua Eng. Álvaro Nunes Pereira, 400/402, Porto Alegre 90570-110, RS, Brazil. ajaciob@gmail.com
Telephone: +55-51-32253682 Fax: +55-51-32253682
Received: October 7, 2018
Peer-review started: October 7, 2018
First decision: October 18, 2018
Revised: December 20, 2018
Accepted: December 31, 2018
Article in press: January 1, 2019
Published online: January 27, 2019
Abstract
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 × 109/L [interquartile range (IQR) = 65–100 × 109/L] on seventh POD, and the lowest was 51 × 109/L (IQR = 38–71 × 109/L) on third POD. The C-statistic defined a PC < 70 × 109/L on fifth POD as the ideal cutoff point for predicting death and retransplantation. In the multivariate analysis, platelets < 70 × 109/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 × 109/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 × 109/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.

Keywords: Predictive factors, Prognosis, Platelet count, Liver transplantation, Graft survival, Mortality

Core tip: Recent evidence shows that low platelet count (PC) can predict outcomes after liver transplantation (LT). We evaluated if a low PC in the immediate postoperative period of LT, defined as a PC < 70 × 109/L on the fifth postoperative day (5POD), is a predictor of death or retransplantation. We retrospectively assessed 480 consecutive LT patients. This study showed that a PC < 70 × 109/L on the 5POD was independently associated with shorter patient and graft survival within one year after LT. These results are in agreement with other studies indicating that thrombocytopenia in the immediate postoperative period of LT is associated with negative outcomes.