Retrospective Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Jan 27, 2021; 13(1): 120-131
Published online Jan 27, 2021. doi: 10.4254/wjh.v13.i1.120
Immunization status and hospitalization for vaccine-preventable and non-vaccine-preventable infections in liver-transplanted children
Palittiya Sintusek, Yong Poovorawan
Palittiya Sintusek, Thai Pediatric Gastroenterology, Hepatology and Immunology Research Unit, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
Palittiya Sintusek, Department of Pediatrics, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Bangkok 10330, Thailand
Yong Poovorawan, Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, Bangkok 10330, Thailand
Author contributions: Sintusek P designed and oversaw the study, drafted the manuscript, collected, interpreted, and analyzed the data, and made critical revisions related to important intellectual content; Poovorawan Y suggested critical intellectual content and approved the final manuscript.
Supported by Thai Pediatric Gastroenterology, Hepatology and Immunology Research Unit, King Chulalongkorn Memorial Hospital, Faculty of Medicine, Chulalongkorn University; The 100th Anniversary Chulalongkorn University Fund for Doctoral Scholarship, Chulalongkorn University; and the Thailand Research Fund Thailand Science Research and Innovation, No. MRG6280190.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of Chulalongkorn University, Thailand (IRB approval number: 806/62).
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 the patient agreed to treatment by written consent.
Conflict-of-interest statement: The authors have no conflicts of interest to disclose.
Data sharing statement: There are no additional data available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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: Yong Poovorawan, MD, Professor, Center of Excellence in Clinical Virology, Department of Pediatrics, Faculty of Medicine, King Chulalongkorn Memorial Hospital, Chulalongkorn University, 1873 Rama IV Road Patumwan, Bangkok 10330, Thailand. yong.p@chula.ac.th
Received: June 25, 2020
Peer-review started: June 25, 2020
First decision: October 21, 2020
Revised: November 12, 2020
Accepted: November 28, 2020
Article in press: November 28, 2020
Published online: January 27, 2021
Processing time: 215 Days and 0.7 Hours
Abstract
BACKGROUND

Infections and associated morbidity and mortality may be more frequent in children who have undergone liver transplant than in healthy children. Immunization strategies to prevent vaccine-preventable infections (VPIs) can effectively minimize this infection burden. However, data on age-appropriate immunization and VPIs in children after liver transplant in Asia are limited.

AIM

To evaluate the immunization status, VPIs and non-VPIs requiring hospitalization in children who have undergone a liver transplant.

METHODS

The medical records of children who had a liver transplant between 2004 and 2018 at King Chulalongkorn Memorial Hospital (Bangkok, Thailand) were retrospectively reviewed. Immunization status was evaluated via their vaccination books. Hospitalization for infections that occurred up to 5 years after liver transplantation were evaluated, and divided into VPIs and non-VPIs. Hospitalizations for cytomegalovirus and Epstein-Barr virus were excluded. Severity of infection, length of hospital stay, ventilator support, intensive care unit requirement, and mortality were assessed.

RESULTS

Seventy-seven children with a mean age of 3.29 ± 4.17 years were included in the study, of whom 41 (53.2%) were female. The mean follow-up duration was 3.68 ± 1.45 years. Fortyeight children (62.3%) had vaccination records. There was a significant difference in the proportion of children with incomplete vaccination according to Thailand’s Expanded Program on Immunization (52.0%) and accelerated vaccine from Infectious Diseases Society of America (89.5%) (P < 0.001). Post-liver transplant, 47.9% of the children did not catch up with age-appropriate immunizations. There were 237 infections requiring hospitalization during the 5 years of follow-up. There were no significant differences in hospitalization for VPIs or non-VPIs in children with complete and incomplete immunizations. The risk of serious infection was high in the first year after receiving a liver transplant, and two children died. Respiratory and gastrointestinal systems were common sites of infection. The most common pathogens that caused VPIs were rotavirus, influenza virus, and varicella-zoster virus.

CONCLUSION

Incomplete immunization was common pre- and post-transplant, and nearly all children required hospitalization for non-VPIs or VPIs within 5 years post-transplant. Infection severity was high in the first year post-transplant.

Keywords: Children; Hospitalization; Immunization; Liver transplant; Thailand; Vaccine-preventable infection

Core Tip: Incomplete age-appropriate immunization in children waiting for a liver transplant was expected, and nearly half of them had not caught up with age-appropriate vaccinations post-transplant. Though there was no significant difference in hospitalization from vaccine-preventable infections (VPIs) and non-VPIs in children with complete and incomplete immunizations. At least 13.1% required hospitalization within 5 years post-transplant, and > 10% were admitted to the intensive care unit and required respiratory support. The severity of infections was high during the first year post-transplant. Complete immunization and robust infection control should be prioritized in children both pre and post-liver transplant.