Effects of respiratory viral pathogens on liver transplantation in children

Aim: The objective is to contribute to national epidemiologic data by identifying the causative agents of viral respiratory infections in pediatric liver transplant patients, preventing clinical progression in high-risk patients through early diagnosis and treatment, evaluating prophylaxis options, and examining the impact of viral infection on the clinical course of primary disease. Methods: The study included 45 liver transplant patients, aged 0 to 18 years, followed up between January 2016 and December 2020 by Istanbul University, Istanbul Faculty of Medicine, Department of Paediatric Gastroenterology, Hepatology, and Nutrition, who were diagnosed with respiratory tract infection and whose viral respiratory panel was examined. 87 viral respiratory infections in these patients were evaluated. Data on patients' characteristics, underlying disease, immunosuppressive treatments, complaints, physical examination, laboratory findings, and treatment procedures were retrospectively analyzed. Results: Of the 45 pediatric liver transplant patients included in the study, 87 viral respiratory infections were evaluated. 66.7% (n=58) of patients were female and 33.3% (n=29) were male. The mean age at admission was 59.3 ± 44.6 months and ranged from 5 to 173 months. A single viral pathogen was found in 73 patients (84%) and more than one pathogen (mixt group) in 14 patients (16%). The most frequently detected virus was RV (41.4%), followed by RSV (13.8%) and influenza (12.6%). While 72.7% of patients with RSV infection complained of wheezing and cough, fewer patients in the RV, hCoV, and mixed groups were admitted with these complaints (p=0.038). There was no difference between the viral agents in terms of clinical, laboratory, and radiological findings. The length of hospital stay of patients with RSV infection was significantly longer than that of patients with hCoV infection (p=0.041). In patients with rhinovirus infection, the rate of continuation of immunosuppressive therapy at the same dose without reduction was significantly higher than for other viral factors (p=0.024). The CRP, PCT values and incidence of elevated CRP in the patients who required hospitalization were significantly higher than the group that did not require hospitalization (respectively p=0.002, p=0.005, p=0.012). Four patients (4.6%) required intensive care admission, and one patient with pulmonary artery stenosis died during the RV infection period. Conclusion: Early detection of the etiology of respiratory tract infections in children with liver transplants can reduce unnecessary antibiotic use, facilitate the management of immunosuppression, and accelerate the establishment of appropriate isolation conditions to reduce hospital-acquired infections. However, current treatments for viral respiratory tract infections are limited, and new antiviral drugs and prophylaxis options are needed. Our study will be a guide for prophylaxis and new treatment options for this special patient group.